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Bivalvia (Mollusca) of the Gulf of Mexico

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... Most of the bivalve species (86%) inhabit marine waters (Morton and Machado 2019), from the intertidal zone to the abyssal plain, as benthic animals. They live on rocks or seagrass, buried in the sand or mud, and even burrow in wood, coral, and rock (Turgeon et al. 2009). Most bivalves use their foot to crawl to suitable areas for attachment or burrowing, some are free-living, and a few can move through the water column (e.g., pectinids and limids), while others can attach to hard surfaces using a byssus or by cementing (Ponder et al. 2019). ...
... Because bivalves are an important component of the benthic infauna and epifauna of aquatic ecosystems, their functional ecological roles are diverse and include: (1) filtration of water, (2) aeration of the substratum through burying in sediment, (3) creation of crevices for other species in coral rock or wood, (4) a source of calcium carbonate after death, (5) a substrate for epibionts, and (6) decomposition of organic matter (Turgeon et al. 2009). Also, this group is relevant ecologically, as some bivalves are exotic and can be invasive, such as Perna viridis (Spinuzzi et al. 2013), while others have economic value (e.g., oysters and mussels in fisheries and aquaculture; Bieler et al. 2013). ...
... Also, this group is relevant ecologically, as some bivalves are exotic and can be invasive, such as Perna viridis (Spinuzzi et al. 2013), while others have economic value (e.g., oysters and mussels in fisheries and aquaculture; Bieler et al. 2013). A summary of studies of this group in the GOM can be found in Turgeon et al. (2009) which is to date the most updated and comprehensive compendium of bivalves from the area, with a reported total of 528 species. Turgeon et al. (2009) provided a checklist for the GOM, which according to the definition of Tunnell and Felder (2009), can be represented as a polygon comprised of all the brackish areas along the coasts of Mexico, Cuba, and the United States, and marine waters bounded in the northeast by an imaginary line between Key Largo (USA) and Punta Hicacos, Cuba (Fig. 1). ...
Article
The Gulf of Mexico (GOM) is bordered by the United States, Mexico, and Cuba and hosts multiple aquatic habitats, including deepwater hydrocarbon seeps, coral reefs, and coastal wetlands. Bivalves are an important component of the GOM fauna, frequently used as bioindicators in ecological studies, and represent the second largest class of Mollusca. Here, we update the bivalve checklist of Turgeon et al. (2009) using recent literature (47 peer-reviewed papers published between 2009 and 2020), the online datasets GBIF and Invert-E-base, and provide records and photographs of specimens collected as part of the Mexican project Biodiversidad Marina de Yucatán (BDMY); we also describe species distributions across two biogeographical regions. We list 640 species of Bivalvia belonging to 314 genera, 75 families, and 17 orders. Our focus on the Campeche Bank yielded 168 species, 128 of those species were photographed, and 11 genera were illustrated here. Areas bordering the United States dominated bivalve diversity at all taxonomic levels, followed by those in Mexico and Cuba. The list includes 16 new described species since 2006 for the GOM, which represents an addition of 2.5% of the reported species almost 15 years ago. In this work, we provided for the first time an illustrated catalog with 128 photographs of 20% of the 640 bivalve species in the list, which were collected at the Campeche Bank, GOM. This study expanded our understanding of bivalve diversity in the GOM and increased the sampling effort to an understudied and remote area. Resumen El Golfo de México (GOM) limita con Estados Unidos, México y Cuba y alberga múltiples hábitats acuáticos, como filtraciones de hidrocarburos en aguas profundas, arrecifes de coral y humedales costeros. Los bivalvos son un componente importante de la fauna del Golfo de México, frecuentemente utilizados como bioindicadores en estudios ecológicos y, representan la segunda Clase más grande de moluscos. En este trabajo actualizamos la lista de bivalvos de Turgeon et al. (2009) utilizando literatura reciente (47 artículos publicados entre 2009 y 2020), bases de datos en línea (GBIF y Invert-E-base) y, proporcionamos registros y fotografías de ejemplares recolectados como parte del proyecto Biodiversidad Marina de Yucatán (BDMY); también describimos la distribución de las especies en dos regiones biogeográficas. Enlistamos 640 especies de Bivalvia pertenecientes a 314 géneros, 75 familias y 16 órdenes. Incluimos 168 especies recolectadas en el Banco de Campeche; de estas, 128 fueron fotografiadas a nivel de especie y 11 a nivel de género. La diversidad de bivalvos en todos los niveles taxonómicos fue mayor en las zonas fronterizas con EE.UU., seguidas por las de México y Cuba. El conjunto de datos incluye 16 especies nuevas descritas desde 2006, lo que representa una adición de 2.5% de las especies reportadas hace casi 15 años. En este trabajo proporcionamos por primera vez, un catálogo ilustrado con 128 fotografías del 20% de las 640 especies de bivalvos de la lista, las cuales fueron recolectadas en el Banco de Campeche, GOM. Este estudio amplió nuestra comprensión de la diversidad de bivalvos en el GOM y dirigió el esfuerzo de muestreo a un área poco estudiada y remota.
... Worn and broken shells suggested transport from elsewhere, or that the organism may have lived in the area, but died long ago. We compared the observed assemblages with an exhaustive inventory of Bivalvia species from the GOM that had information on depth range and habitat preferences [39]. The list, however, did not distinguish between provenance of live and dead shells in the records, and provided only general location data for species presence/absence information, without specific geographic coordinates, thus precluding site-specific comparisons. ...
... Previous studies [22,27,40,72] also found very low numbers of live bivalve mollusks in these types of habitats, made no distinction between live and dead specimens, and covered a huge area [39,73,74]. Simply because its enormous size, there is a lack of detailed information about the geographical distribution of bivalves across important regions of the Mexican part of the PFB. ...
... Overall geographic range. The species has been reported from North Carolina to Texas, Cuba, and Brazil, at depths of 0-120 m, benthic and infaunal [39]. ...
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Mollusk diversity in coastal areas of the Gulf of Mexico (GOM) has been studied extensively, but this is not the case for deep-water habitats. We present the first quantitative characterization of mollusks in shallow and deep waters of the Perdido Fold Belt. The data came from two research cruises completed in 2017. Sediment samples were collected from 56 sites using a 0.25-m2 box corer. We tested hypotheses about spatial patterns of of α, β, and γ-diversity of bivalves in two water-depth zones, the continental shelf (43–200 m) and bathyal zone (375–3563 m). A total of 301 bivalves belonging to 39 species were identified. The two zones display similar levels of -diversity, but host different bivalve assemblages. In general, of α-diversity was higher on the continental shelf, whereas of β-diversity was higher in the bathyal zone. These patterns can be explained by the higher input of carbon (energy) to the near-coast shelf zone, as well as by the greater topographic complexity of habitats in the bathyal zone. These results enabled us to propose redirection of sampling efforts for environmental characterization from continental zones to the deep-water zone, especially in the context of environmental assessments during oil and gas exploration and production.
... Species records for molluscs in the Gulf of Mexico were retrieved from occurrence data archived in the BioGoMx database (Moretzsohn et al., 2011), which includes species depth and geographic distributions based on the data and expertise of the 140 taxonomists that assembled the database (Moretzsohn et al., 2011). From the available data, we could not distinguish which records were based on live vs. dead shells for shelled-gastropods and bivalves (Turgeon et al., 2009) and so all location data were included for these taxa. We also could not distinguish if records were for singleton occurrences based on the database literature. ...
... A few species were also listed with the addition of "cf." for uncertain species identification; these were treated as operational taxonomic units, and included in subsequent analyses. Feeding strategies were assigned to each species following the original designations determined by taxonomists involved in the original compilation of the database (Ivanov and Scheltema, 2009;Judkins et al., 2009;Kraeuter, 2009;Lyons and Moretzsohn, 2009;Rosenberg et al., 2009;Turgeon et al., 2009). Those species without a designation in the database were assigned one using WoRMS or by referencing the primary literature (Table A1). ...
... Chemosynthetic cold seep habitats are especially abundant in the GOM and host an abundance of limpets, and symbiont-bearing bivalves (Kennicutt, 2017). Endosymbiont-bearing mussels in the GOM may also inhabit wood falls Turgeon et al., 2009). MDS for mollusc class resemblance matrices. ...
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The Biodiversity of the Gulf of Mexico (BioGoMx) database, which contains occurrence information of extant species in the Gulf of Mexico (GOM), allows for the analysis of benthic mollusc diversity and distribution across the entire basin. For analyses, the GOM was split in 4 geographic sectors (NE, NW, SE, and SW) and 6 depth classes (inshore, upper shelf, lower shelf, upper slope, lower slope, and abyssal plain) for a total of 24 geographic-depth polygons. The northern GOM contained higher species richness than the south, the east more than the west. Species richness decreased with depth with maxima occurring on the upper shelf. Bivalves and gastropods dominated each geographic sector and depth class, together comprising >90% of the molluscan species richness. Assemblages were structured by depth more than by geographic sector. GOM molluscs fell into 3 broad depth-based assemblages: the inshore and continental shelf, the continental slope, and the abyssal plain species combined with the western lower slope. Geographically, taxonomic distinctness analysis indicated most NE depths fell below average distinctness and by depth polygons above and below the continental shelf break were frequently distinct. Cluster analysis based on taxonomic dissimilarity agreed with the analyses based on the species occurrence data. Mollusc feeding strategies largely followed estimated proportions for the larger Atlantic. Carnivory and suspension feeding were the most common with grazing, herbivory, and parasitism following behind. Chemosymbiotic species were also prevalent due to the widespread occurrence of cold seep habitats. Further taxonomic research and more sampling are needed to determine patterns at finer scales.
... Distribution. Japan (Turner, 1966); Mediterranean Sea (Borges et al., 2014a); Gulf of Mexico (Turgeon et al., 2009); Caribbean Sea (Turner, 1966). Venezuela, Gulf of Cariaco (Nair, 1979) and Gulf of Mexico (Turner, 1966); Tobago (Distel et al., 2011). ...
... Distribution. Gulf of Mexico (Turgeon et al., 2009); Caribbean Sea: Venezuela, Maracaibo Lake (Ewald et al., 1984), Amuay Bay (Turner and Brown, 1953), Gulf of Cariaco (Nair, 1979); Western Atlantic: New Jersey, USA to Brazil (Díaz and Puyana, 1994;Junqueira et al., 1991;Varotto and Barreto, 1998). North Eastern Pacific Coast (Tuner, 1966;Coan and Valentich-Scott, 2012;Cruz et al., 1989). ...
... Distribution. Pacific coast of Colombia (Cantera, 2010); Gulf of Mexico (Turgeon et al., 2009); Venezuela (Amuay Bay: Turner and Brown, 1953;Gulf of Cariaco: Nair, 1979; Maracaibo Lake: Rojas and Severeyn, 2000); Brazil (Junqueira et al., 1991;Varotto and Barreto, 1989;Barreto et al., 2000;Lima et al., 2005; Martins-Silva and Narchi, 2008). ...
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This study provides the first comprehensive survey of wood-boring bivalves from the family Teredinidae in Venezuelan coastal waters. Surveys were carried out between 2004 and 2014 and a total of fifteen species from seven genera are reported, including three new records for Venezuelan coastal waters (Teredo johnsoni, Lyrodus bipartitus) and one new record for the Caribbean Sea (Nausitora dunlopei). A previously reported species (Bankia martensi), typically thought to be restricted to cooler southern waters, was not found in this extensive survey and is highlighted as an incorrect record and species misidentification. The diversity of wood-boring bivalves in Venezuelan waters represents one of the highest diversities outside the Indo-Pacific region. Descriptive information for each species is provided, including taxonomic and/or ecological notes. In addition, images of the pallets - the primary taxonomic character for species identification - are provided and compared with specimens from malacological collection at the Harvard Museum of Comparative Zoology (Cambridge, Massachusetts, USA) to corroborate identification.
... Distribution: Northwestern Atlantic Ocean, from Canada to Florida (Bousfield 1960;Hebda 2011;Mikkelsen and Bieler 2007;Turgeon et al. 2009), Brazilian coast (Rios 2009), Senegal to Congo (Barnard 1964;Cosel and Gofas 2019), Bahía Blanca, Argentina (Fiori et al. 2012, reported as introduced). ...
... This species was widely reported from eastern and western Atlantic Ocean. Genetic studies on specimens of Canadian (Bousfield 1960;Hebda 2011;Mikkelsen and Bieler 2007;Turgeon et al. 2009;Turner 1954), African (Barnard 1964;Cosel and Gofas 2019) and Argentine waters (Fiori et al. 2012;Schwindt et al. 2020) will clarify this wide distribution range. Type species: Pholas cruciger G.B. Sowerby I, 1834 by subsequent designation (Stoliczka 1870(Stoliczka , 1871. ...
Article
Boring bivalves of the family Pholadidae Lamarck, 1809 living in Argentinean and Uruguayan waters are herein revised. The literature research revealed twelve nominal species of Pholadidae mentioned as living in the study area. Type material of all nominal taxa were examined when it was possible. Additional specimens from field works and malacological collections were studied, illustrated and re-described. Details of type localities, repositories, and distribution range are provided for each valid taxa. This work revealed the presence of five native and one introduced species belonging to Pholadidae in Argentinean and Uruguayan waters. Barnea (Anchomasa) lamellosa, Cyrtopleura (Scobinopholas) lanceolata, Pholas (Thovana) campechiensis and Martesia fragilis belonging to the Argentine biogeographical province; Netastoma darwinii from Magellan province; and Barnea (Anchomasa) truncata introduced in the Bahía Blanca estuary. Finally, morphological comparison with congeneric species distributed in American seas are provided.
... We classified the species after five biological traits: (i) life mode, (ii) feeding type, (iii) relationship with the substrate, (iv) mobility, and (v) shell attachment (S1 Table). The biological traits were mainly obtained from the database Neogene Marine Biota of Tropical America (NMITA) [44], including support literature for mollusk ecology [40,41,45,46]. All categories within traits were adapted following the codes given at NMITA. ...
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Mollusk death assemblages are formed by shell remnants deposited in the surficial mixed layer of the seabed. Diversity patterns in tropical marine habitats still are understudied; therefore, we aimed to investigate the taxonomic, phylogenetic, and functional diversity of mollusk death assemblages at regional and local scales in coral reef sands and seagrass meadows. We collected sediment samples at 11 sites within two shallow gulfs in the Northwestern Caribbean Sea and Southeastern Gulf of Mexico. All the shells were counted and identified to species level and classified into biological traits. We identified 7113 individuals belonging to 393 species (290 gastropods, 94 bivalves, and nine scaphopods). Diversity and assemblage structure showed many similarities between gulfs given their geological and biogeographical commonalities. Reef sands had higher richness than seagrasses likely because of a more favorable balance productivity-disturbance. Reef sands were dominated by epifaunal herbivores likely feeding on microphytobenthos and bysally attached bivalves adapted to intense hydrodynamic regime. In seagrass meadows, suspension feeders dominated in exposed sites and chemosynthetic infaunal bivalves dominated where oxygen replenishment was limited. Time averaging of death assemblages was likely in the order of 100 years, with stronger effects in reef sands compared to seagrass meadows. Our research provides evidence of the high taxonomic, phylogenetic, and functional diversity of mollusk death assemblages in tropical coastal sediments as result of the influence of scale-related processes and habitat type. Our study highlights the convenience of including phylogenetic and functional traits, as well as dead shells, for a more complete assessment of mollusk biodiversity.
... An alien species recently discovered in the Baltic (Warzocha and Drgas 2013) is the Atlantic rangia (Rangia cuneata G.B. Sowerby I, 1832), a bivalve native to the Gulf of Mexico, which by the 1960s had expanded its range northward to the Chesapeake Bay and the lower parts of the Hudson River (Turgeon et al. 2009). It was initially discovered in European waters in August 2005 (Verween et al. 2006), in the harbor waters of Antwerp, Belgium, from where the species later expanded to the estuaries of the southern and northern North Sea (Neckheim 2013). ...
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The native North American bivalve species Rangia cuneata was unintentionally introduced into European waters during the first decade of the 21 st century. In the Baltic Sea, it is mostly found along the southeastern coast, but in 2018 researchers also discovered the species in the Bay of Pomerania, which indicated that it could eventually inhabit the adjacent Szczecin Lagoon and Odra River. In 2021, the species was discovered for the first time in the Szczecin Lagoon during a sampling campaign, at 5 out of the 12 dispersed study sites with diverse bottom substrates. The goal of this study was to ascertain R. cuneata population density, morphometric parameters, individual growth, and the potential for further expansion in the southern Baltic Sea waters. For the study, 201 individuals of this species were collected. Compared to other sites in the southeast Baltic, the Szczecin Lagoon had a much lower average R. cuneata population density, at 13.2 ± 7.11 individuals m ⁻² of the bottom area. The highest population density was found at sites with more silt (4–63 µm) and less sand (>63 µm). R. cuneata shells had an average length of 30.9 ± 4.6 mm and an average weight of 6.6 ± 2.8 g. The collected specimens were greater in size than other populations of the species in the Baltic Sea and were comparable in size to populations from the nearby Bay of Pomerania. There were no specimens that were under 10 mm in length, and the population was dominated by specimens in the 25–30 mm and 30–35 mm ranges, as well as the 3+ and 4+ age groups. Given the R. cuneata ’s invasive potential and its fast rate of colonization of new areas, it would be prudent to monitor this population and the species migration patterns across the estuary waters of the western Baltic.
... Gaps in our knowledge of historical biotic changes often stem from a paucity of information about species geographic distributions, community species richness and evenness, community structure, ecological interactions, and factors that caused past biotic shifts. Nevertheless, recent marine mollusc inventories have begun to expand our knowledge of the biota and environmental conditions in some regions, such as the Gulf of Mexico Reguero, 2004, 2007;Mikkelsen and Bieler, 2008;Moretzsohn et al., 2009;Ortigosa et al., 2018;Rosenberg et al., 2009;Turgeon et al., 2009;Vokes and Vokes, 1983;Wingard andStackhouse, 2020a, 2020b;Wingard and Surge, 2017), and in Río Lagartos coastal lagoon (Gonzalez et al., 1991;Suárez-Mozo et al., 2023). Molluscs meet many of the criteria required for organisms to be good bioindicators. ...
... All the species found in the Río Lagartos coastal lagoon have been reported previously from other lagoons around the Gulf of Mexico ( Figure 9) and 22 species were reported earlier from the Caribbean (García-Cubas & Reguero, 2004& Reguero, , 2007Rosenberg et al., 2009;Turgeon et al., 2009). The high number of shared species between the Gulf of Mexico and the Caribbean is attributable to the dispersal of larvae by the Yucatán Current. ...
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Molluscs are a diverse phylum in coastal lagoons because the numerous taxa collectively display broad ranges of optima and tolerance with respect to ambient conditions. We report on the taxonomic composition, habitat preferences and feeding guilds of molluscs from Río Lagartos coastal lagoon, Mexico. Molluscs were collected in the rainy season (September/October 2017), during the winter ( Nortes ) season (February 2018) and at the end of the warm, dry season (May 2018). Samples were taken using a Ponar dredge, a cylindrical PVC core barrel, or a beach seine. We studied the abiotic characteristics (sediment grain-size distributions, submersed aquatic vegetation abundance and salinity) to explore assemblage differences across the broad salinity gradient that characterizes the system (~30–78 PSU). Molluscs were represented by 39 species, 34 genera, 23 families and two classes. Stenohaline species were more numerous overall than euryhaline species, but their occurrence in samples was low (<20% of the samples). Stenohaline taxa lived primarily in environments characterized by marine salinity, and few were found under hypersaline conditions. We collected a smaller number of species than did studies carried out in the lagoon >35 years ago. Species accumulation curves revealed that the full species richness was not captured in our study. Euhaline environments displayed greater mollusc species richness and had a larger proportion of amount (mass) of submersed aquatic vegetation. In the hypersaline environments, species richness may be favoured by the lower dominance of sands. Suspension feeders were the most diverse group in both the euhaline and hyperhaline environments.
... Significantly, however, D. variabilis was identified as both first and second intermediate hosts of these digeneans in the Gulf of Mexico, but neither sporocyst nor cercaria was found in this species on the SC coast, a finding brought to light only after we molecularly identified all the individual clams serving as first intermediate hosts of these three digeneans in our collections. Thus, given the long term and recurrent issue with Donax species misidentification [1,2,45], and because D. variabilis lives in sympatry with the cryptic species D. texasianus in the Gulf of Mexico [1,2,60], it is then highly probable that the first intermediate host from these earlier studies was in fact misidentified. This is supported by a detail in Loesch [38], who reported infection by Cercaria A (i.e., presumed Cercaria choanura of Hopkins [30] and Lasiotocus choanura herein) in D. variabilis in the text, but illustrated it as being from D. tumida (= D. texasianus; [17,45]) as he found one infected individual of this species. ...
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The coquina, Donax variabilis , is a known intermediate host of monorchiid and gymnophallid digeneans. Limited morphological criteria for the host and the digeneans’ larval stages have caused confusion in records. Herein, identities of coquinas from the United States (US) Atlantic coast were verified molecularly. We demonstrate that the current GenBank sequences for D. variabilis are erroneous, with the US sequence referring to D. fossor . Two cercariae and three metacercariae previously described in the Gulf of Mexico and one new cercaria were identified morphologically and molecularly, with only metacercariae occurring in both hosts. On the Southeast Atlantic coast, D. variabilis ’ role is limited to being a facultative second intermediate host, and D. fossor, an older species, acts as both first and second intermediate hosts. Sequencing demonstrated 100% similarities between larval stages for each of the three digeneans. Sporocysts, single tail cercariae, and metacercariae in the incurrent siphon had sequences identical to those of monorchiid Lasiotocus trachinoti , for which we provide the complete life cycle. Adults are not known for the other two digeneans, and sequences from their larval stages were not identical to any in GenBank. Large sporocysts, cercariae ( Cercaria choanura ) , and metacercariae in the coquinas’ foot were identified as Lasiotocus choanura (Hopkins, 1958) n. comb. Small sporocysts, furcocercous cercariae, and metacercariae in the mantle were identified as gymnophallid Parvatrema cf. donacis . We clarify records wherein authors recognized the three digenean species but confused their life stages, and probably the hosts, as D. variabilis is sympatric with cryptic D. texasianus in the Gulf of Mexico.
... More recent records for Jouannetia quillingi include Northeast Florida (Lee 2009], the West coast of Florida (Camp et al. 1998], and Stetson Bank off Texas in the NW Gulf of Mexico (Turgeon et al. 2009]. Rosenberg (2009] fails to mention either the records for North Carolina or Texas, despite considerable prior documentation (Andrews, 1971;Porter, 1974]. ...
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Three species of boring bivalve mollusks were recovered from a piece of driftwood beached on Portsmouth Island, North Carolina, March 15 2014. These were the fallen angel wing Barnea truncata (Say, 1822), the wedge piddock Martesia cuneiformis (Say, 1822), and the spiny piddock Jouannetia quillingi Turner, 1955. The latter species represented only the third known NC record for the species— the previous one having been reported by Wolfe in 1968 as living burrowed in rock at 15 fathoms depth off Beaufort.
... The former is a known host of G. chamae (see Roberts, 1975), while the second species is listed among the multiple hosts of Tumidotheres maculatus (Say, 1818) (Schmitt et al., 1973). The known distribution of Ch. congregata extends from North Carolina to Texas, USA, Tamaulipas to Yucatán, Mexico, Cuba, Honduras, West Indies, Bermuda and Brazil (García-Cubas and Reguero, 2007;Turgeon et al., 2009;Correa-Sandoval and Rodríguez-Castro, 2013). However, the Brazilian population of Ch. congregata may represent a different Gemmotheres chamae from the Gulf of Mexico Nauplius, 28: e2020005 species (Campbell et al., 2004). ...
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An adult female of the Jewel-Box clam crab Gemmotheres chamae (Roberts, 1975) was collected from a shrimp trawl during a biological exploration off Campeche coast, Mexico. This finding represents its first record in the Gulf of Mexico and the second locality for this species along the Atlantic coast of America, the first being from off North Carolina, U.S.A. As an adult, G. chamae has a soft, thin carapace, and a subconical protuberance on article 1 of the antennae (with the nephridiopore of the antennal gland), so it is considered to belong to the Pinnotherinae sensu stricto. G. chamae and Nannotheres moorei Manning and Felder, 1996 (Atlantic) are the only members of the American Pinnotherinae sensu stricto that have the maxilliped 3 with a 2-segmented palp. The asymmetry of pereiopod 3 is confirmed, as well as that of the pereiopod 4, but the right legs are the longest. All these features are diagnostic for G. chamae.
... Introduction. Bivalves can be found under phylum Mollusca, class Bivalvia, with about 10,000 living species throughout the world from freshwater lakes to the deepest abyss (Huber 2015;Rahman et al 2015;Turgeon et al 2009). They are soft-bodied invertebrates enclosed by two calcified valves joined by a two-hinged ligament (Yahya et al 2016). ...
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Bivalves are filter feeders that play important roles in providing food for local communities, as well as promoting ecosystem stability. A study of bivalve diversity, distribution and abundance, was conducted in the intertidal area of Ngemboh, Gresik, East Java, Indonesia, in March 2018, during rainy season. The aim was to investigate the ecological indices, like species richness and species abundance, as well as the environmental parameters that might influence these bivalve communities. Three replicates of 15 m transect lines with five 1x1 m quadrant plots in each line were set up seawards, perpendicular to the coastline. All bivalves in the quadrants were counted. There were 278 individual bivalves from 11 species, 8 genera, and 5 families in the research areas. On average, the species abundance was 3.08 ind/m 2. The values for Shannon's diversity index (H'), Pielou's evenness index (J'), and Simpson's dominance index (C) were 1.16, 0.82 and 0.34, respectively. The Pearson correlation showed that the dissolved oxygen (DO) had a very high correlation with both species richness and diversity index (r=0.93 and r=0.92 respectively, P<0.01). Furthermore, Gafrarium pectinatum dominated 30% of the total abundance from all stations, suggesting this species to strongly shape the ecologicall indices in most research stations.
... The native distribution of Mulinia lateralis is the western Atlantic Ocean, ranging from the Gulf of St Lawrence to the Gulf of Mexico (Brunel et al. 1998;Turgeon et al. 2009). It is widely reported from bays along the Atlantic and Gulf coasts of the U.S., in a large range of salinities, from 5 to 80 ppt (Parker, 1975in Montagna et al. 1993). ...
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This paper reports the first records of the dwarf surf clam Mulinia lateralis (Say, 1822) outside its native area, which is the western Atlantic Ocean, ranging from the Gulf of St Lawrence to the Gulf of Mexico. In 2017 and 2018 specimens were found in the Dutch coastal waters (North Sea), in the Wadden Sea and in the Westerschelde estuary, in densities of up to almost 6000 individuals per square meter. In view of its ecology and distributional range in the native area M. lateralis has the potential to become an invasive species. Its ability to quickly colonize defaunated areas, its high fecundity and short generation time, its tolerance for anoxia and temperature extremes and its efficient exploitation of the high concentrations of phytoplankton and natural seston at the sediment-water interface may bring it into competition with native species for food and space.
... In marine environments, the mollusks habitats are from the intertidal areas to the deepest abyss. Bivalves bury themselves in sand or mud, attach to mangrove leaves, crawl on seagrass blades, attach to shells and rocks, and even bury in driftwood and coral rocks (Keast 2000;Turgeon et al 2009;van der Meij et al 2009). Overall, there are 8,500 valid species of all marine and brackish water specimens currently recognized (Huber 2015). ...
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Bivalves play an important role in regulating bodies of water as well as in providing a wide range of ecosystem services including habitat complexity provision. A study of bivalve community structures in intertidal areas of Lamongan regency was conducted in June 2017 during the beginning of the dry season. It aimed to assess the species richness and ecological indices, as well as to analyze physicochemical parameters that might influence the community structures. Three 50-m long transect lines in each station were laid perpendicular to the coastline with five 1 x 1 m quadrant transects in each line. Results showed that there were 4 families, 8 genera and 8 species of bivalves of which Gafrarium pectinatum had the highest density, representing 82% of all bivalve individuals. On average, the Shannon's diversity index (H') and the Pielou's evenness index (J') were 0.4 and 0.35 respectively, while the Simpson dominance index (D) was 0.75. Ostreidae was evenly distributed and probably played an important role to govern the higher diversity and evenness indices, while G. pectinatum was responsible for the low value of diversity and evenness indices as well as the high value of the dominance index.
... Nuculana acuta is a deposit-feeding, infaunal, protobranch bivalve that commonly occurs in organic-rich sands (Mikkelsen and Bieler 2008;Tunnell et al. 2010). Nuculana acuta live between 0 and -274 m throughout the Gulf (Turgeon et al. 2009;Tunnell et al. 2010). Nuculana are lecithotrophic and have relatively large eggs, short larval durations (, 12 hours), and limited dispersal distances (Ansell et al. 1978;Marine Macrofauna Genus Trait Handbook 2017). ...
Article
Natural and anthropogenic eutrophication can increase food supply to basal consumers in aquatic food webs. All else being equal, increased food supply is expected to relax life history trade-offs between egg size and number, resulting in a reduction in egg size over time as individuals that produce more numerous, small eggs exhibit greater fitness. We tested this hypothesis by comparing the sizes of larval shells (PI) of the marine bivalve Nuculana acuta in living and death assemblages collected from surficial seafloor sediments on the Alabama continental shelf; PI size is positively correlated with egg size and can be measured from adult shells. We found that the mean PI size of living N. acuta was approximately three microns smaller than that of the associated death assemblage and that this difference was robust to potential taphonomic biases. This life history shift occurred relatively recently as no trend exists in PI size over the past 3100 years. The live-dead disagreement that we observed is consistent with the history of anthropogenic eutrophication in the Mississippi Bight. These data provide a baseline for comparison with other regions in the Gulf of Mexico that have more sustained histories of anthropogenic eutrophication. More broadly, live-dead comparisons of molluscan life history coupled with age dating of molluscan shells can complement community-level metrics when assessing the impacts of anthropogenic eutrophication on coastal ecosystems, and offer a unique study system for investigating life history adaptation in a field context.
... The Eastern oyster is easily recognized and distinguished from other species by the deep purple muscle scar, centrally located, on the interior of each valve. Eastern oysters are bivalve mollusks in the family Ostreidae, and there are six total species found in this family within the Gulf of Mexico (Turgeon et al. 2009). The range of this species is from the Gulf of St. Lawrence in Canada through the Gulf of Mexico to the Yucatán Peninsula in Mexico (Galtsoff 1964) and perhaps further south (Carriker and Gaffney 1996). ...
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Four of the five top species in the Gulf of Mexico by value and poundage of landings are shellfish species. Gulf-wide, there are at least 49 officially recognized shellfish species: 28 are mollusks, 18 are crustaceans, and three are echinoderms. Of these, 16 shellfish species are taken within US waters, 46 from Mexico, and 6 from Cuba. The major focus is on the northern Gulf species of brown, pink, and white shrimp, Eastern oyster, and blue crab. All species are known to vary widely or fluctuate in population levels in accordance with varying environmental conditions from year to year. In addition, shrimp have also been affected by exogenous factors, such as rising fuel costs, market competition from imported shrimp, and fleet damage from hurricanes. Shrimp populations seem to be flourishing, while the shrimp fishery is in decline. The oyster fishery appears to be fairly stable overall, except for hurricane damage in some places and a decadal decline in stock assessment in Louisiana. Oyster reef habitat loss is a major concern. The blue crab fishery is quite variable from state to state with Louisiana showing continued growth and the largest fishery over the past two decades, while Texas shows a decrease. Gulf-wide, there is agreement that healthy bays and estuaries lead to more productive fisheries; thus, habitats need to be conserved or in some cases, restored.
... The scientific names of the recorded species in each period were standardized according to current taxonomic nomenclature, using nomenclature checklists (Espinosa y Ortea, 1998, 2001, 2003Ortea & Espinosa, 2001;Mikkelsen & Bieler, 2008;Rosenberg et al., 2009;Turgeon et al., 2009). The taxonomic ordination was also updated (Bouchet et al. (2005) and Espinosa et al. (2005)). ...
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The cyclonic activity within the Gulf of Batabanó has been historically documented and, in the past two decades, it has been possible to observe signals of environmental degradation in its physical and biological state. Yet a study aimed at evaluating the effects of cyclonic activity on the taxonomic diversity of mollusks has not been made. The objective of this study was to evaluate the effects of cyclonic activity during 1981-1985 and 2004-2009 on the taxonomic diversity of soft-bottom mollusks of this region. To measure the cyclonic activity, the Power of Dissipation Index for hurricanes (PDI) was used. The average taxonomic distinctness index (Delta+ ) and the variation in the taxonomic distinctness (Lambda+ ) of the inventory of the mollusks species for both periods were used as a measure of taxonomic diversity. We detected high cyclonic activity (HCA) during 2004-2009 and low cyclonic activity (LCA) during 1981-1985. The taxonomic composition during both periods was made up of 3 classes, 20 orders, 68 families, 155 genus, and 208 species. Significant differences in the taxonomic composition between the two periods were detected, due principally to the loss of genus and species. The taxonomic distinctness index reveals significant changes of the taxonomic structure of mollusks during 2004-2009, which is related to a rise in cyclonic activity. These results suggest that the taxonomic diversity of mollusks was less complex during 2004-2009 than during 1981-1985.
... The scientific names of the recorded species in each period were standardized according to current taxonomic nomenclature, using nomenclature checklists (Espinosa y Ortea, 1998, 2001, 2003Ortea & Espinosa, 2001;Mikkelsen & Bieler, 2008;Rosenberg et al., 2009;Turgeon et al., 2009). The taxonomic ordination was also updated (Bouchet et al. (2005) and Espinosa et al. (2005)). ...
Article
The cyclonic activity within the Gulf of Batabanó has been historically documented and, in the past two decades, it has been possible to observe signals of environmental degradation in its physical and biological state. Yet a study aimed at evaluating the effects of cyclonic activity on the taxonomic diversity of mollusks has not been made. The objective of this study was to evaluate the effects of cyclonic activity during 1981-1985 and 2004-2009 on the taxonomic diversity of soft-bottom mollusks of this region. To measure the cyclonic activity, the Power of Dissipation Index for hurricanes (PDI) was used. The average taxonomic distinctness index (Delta+) and the variation in the taxonomic distinctness (Lambda+) of the inventory of the mollusks species for both periods were used as a measure of taxonomic diversity. We detected high cyclonic activity (HCA) during 2004-2009 and low cyclonic activity (LCA) during 1981-1985. The taxonomic composition during both periods was made up of 3 classes, 20 orders, 68 families, 155 genus, and 208 species. Significant differences in the taxonomic composition between the two periods were detected, due principally to the loss of genus and species. The taxonomic distinctness index reveals significant changes of the taxonomic structure of mollusks during 2004-2009, which is related to a rise in cyclonic activity. These results suggest that the taxonomic diversity of mollusks was less complex during 2004-2009 than during 1981-1985.
... The latter begin as calcium carbonate nodules formed by differential erosion of cap rock that originated from anaerobic bacteria acting on the minerals within the underlying salt domes, which subsequently become overgrown by a suite of encrusting macroalgae, e.g., members of the coralline algal orders (see above), the red algal order Peyssonneliales and the brown algal order Dictyotales (Gore 1992). These rhodolith beds harbor a diverse assemblage of Bivalvia (Turgeon et al. 2009), whose shells provide additional substrata for encrusting coralline algae ). ...
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In the Northwestern Gulf of Mexico (NWGMx), subtidal rhodolith beds offshore Louisiana at 45–80 m depth harbor a diverse community of uncharacterized non-geniculate coralline algae including both biogenic and autogenic rhodoliths and other encrusting taxa. Identifying specimens to their correct genus and species is an ongoing process because many available names remain to be validated by comparison to type specimens. Here, comparative DNA sequencing (psbA, UPA, and COI) and scanning electron microscopy (SEM) are used to assess the molecular and morphological diversity of the rhodolith-forming specimens belonging to the generic concept of Lithothamnion. Phylogenetic and species delimitation analyses of the newly generated sequences from recently dredged specimens at Ewing and Sackett Banks offshore Louisiana reveal the presence of at least six species of Lithothamnion, whose generic placement is confirmed by SEM images of features considered characteristic for the genus. More broadly, our analyses indicate at least eight Lithothamnion species are found in the Gulf of Mexico. Phylogenetic analyses of single (psbA and COI) and concatenated markers (psbA, COI and UPA) show that Lithothamnion is polyphyletic.
... The species Anomalocardia brasiliana occurs in the Gulf of Mexico and the Caribbean Sea and throughout the Brazilian coast (Turgeon et al. 2009). Like other bivalve molluscs of the family Veneridae, A. brasiliana is a filter feeder and inhabits sandy-muddy sediments in coastal inlets, bays, and estuary mouths. ...
Article
This study describes the larval development of the Venerid bivalve mollusc Anomalocardia brasiliana "berbigão" under laboratory conditions. The clams were collected at Mangue Seco beach (Pernambuco, northeastern Brazil) and transferred to the laboratory where their gametes were released spontaneously. Trochophore and D larvae were identified in the hatchery from 18 to 24 h afterward. Dlarvae had an average length (L) of 71.9 μm, remaining at this stage until the 5th day, when first umbo veligers appeared (L = 115.9 μm). Pediveliger larvae (L = 183.2 μm) were observed after the 9th day. Within 15 days larvae reached juvenile stage (L = 282.0 μm) with growth lines in the shells. Survival was 58.8%, 20%, 60%, and 100% for D larvae, umbo veligers, pediveligers, and juveniles, respectively. To our knowledge, this is the first report of the hatchery rearing for A. brasiliana and serves as a basis for future research and culture of this species.
... Comparative T. clappi has wide distribution in tropical and subtropical waters. Gulf of Mexico (Turgeon, Lyons, Mikkelsen, Rosenberg, & Moretzsohn, 2009); Caribbean Sea, Puerto Rico (Turner & Johnson, 1971); Brazil (Rocha et al., 2013); North Atlantic (West coast), Florida, USA (Bartsch, 1923;Turner, 1966;Turner & Johnson, 1971); Red Sea, Persian Gulf (Turner, 1966); Indo-Pacific: Madagascar; Indonesia (Turner, 1966); Philippines (Betcher, 2011); Australia (Brearley, Chalermwat, & Kakhai, 2003); New Guinea (Turner, 1966;Rayner, 1983); Hawaiian Islands (Coles, DeFelice, Eldredge, & Carlton, 1997;Edmondson, 1942); India (West coast) (Santhakumaran, 1994). ...
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We document the first record of the shipworm Teredo clappi (Bartsch, 1923) in Venezuelan coastal waters. We obtained individuals of T. clappi during 2 years at the El Morro Lagoon, Margarita Island. This record confirms the establishment of this species in the region.
... The genus Lyonsia is widely distributed in the western Atlantic, with a group of species (Lyonsia arenosa, Lyonsia granulifera, Lyonsia fl oridana and Lyonsia hyalina) restricted to northern localities, from the Gulf of Mexico (Turgeon et al. 2009, Tunnel et al. 2010 to Canada and a few isolated records of L. hyalina and L. fl oridana in the Caribbean (Warmke andAbbott 1962, Knudsen 2005). ...
Article
The genus Lyonsia Turton, 1822 is represented in the southwestern Atlantic Ocean by three species: Lyonsia hyalina (Conrad, 1831), which is very common on the east coast of the U.S. A. and has a few isolated records from Brazil and Uruguay; Lyonsia malvinensis d'Orbigny, 1846, known only from the Falkland (Malvinas) Islands; and Lyonsia alvarezii d'Orbigny, 1846, restricted to southern Brazil, Uruguay and Argentina. Some authors consider L. alvarezii a synonym of L. hyalina. Study of material deposited in malacological collections (including types) allowed a redescription of L. alvarezii and its comparison with L. hyalina. Lyonsia alvarezii is characterized by markedly inequilateral valves, with the umbo well dislocated to the anterior region. It has considerable intraspecific variation, mainly in the ventral outline, from almost straight to sinoidal, and at the umbo, from pointed to slightly rounded. The arrangement of spinules on the outer surface of the shell is irregular, usually consisting of three to five radial rows between each pair of radial lines. Previous records of L. hyalina from southern Brazil and Uruguay were based on misidentifications of shells of L. alvarezii and of Lyonsia celeste n.sp. The latter is diagnosed by its elliptical shell, with the anterior, posterior and ventral outline rounded; its subequilateral valves; and the shell spinules restricted to the umbo region of the shell surface. Four species occur on the coast of Canada and the U.S.A: L. arenosa (Moller, 1842), L. granulifera Verrill and Bush, 1898, L. hyalina and L. floridana Conrad, 1849. Three are restricted to the southwestern Atlantic: Lyonsia alvarezii has a wide distribution, from shallow waters in northeastern (similar to 3 degrees S) and southeastern Brazil (similar to 2 degrees 3S) to Argentina (similar to 4 degrees 1 S); L. malvinensis is restricted to the Falkland Islands; and Lyonsia celeste n.sp. is known only from Uruguay and Argentina.
Article
The study was conducted as part of the Joint Vietnam–Russia Tropical Science and Technology Research Center’s project on indicator organisms in the marine environment of south-central Vietnam. The research focused on coastal areas with significant anthropogenic impacts, revealing that biological resources directly affect the livelihood and activities of coastal populations. These resources are dynamic and subject to both human and natural factors. The material from the soft-bottom zone was collected using a grab rake with a mesh bag at the end. Scuba diving equipment was used in areas with a hard substrate and mudflats. In addition, during sample collection, several mollusc specimens were acquired from fishermen who cought marine organisms in that lagoon. Comparing the results with previous studies on bivalve resources in the area, the Nha Phu Lagoon was found to harbour a wide range of economically valuable bivalve species. A total of twenty-seven bivalve species from thirteen families were identified, with the family Veneridae having the highest number of species (eight). The most abundant catches were from the families Ostreidae and Mytilidae, primarily consisting of Magallana gigas (Thunberg 1793) and Perna viridis (Linnaeus 1758), both cultured in the lagoon. Apart from their economic value, these two species also play crucial roles in the ecosystem by filtering water and retaining organic debris in the environment.
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After revising the literature and consulting the pertinent virtual databases, we here list all Brazilian marine bivalves currently considered as valid and include data on their geographical and bathymetrical distribution. The list contains 516 indigenous and nine introduced species. Among the former, 461 species are autobranchs and 64 are protobranchs. They belong to 42 superfamilies, nine of them containing at least 20 species each; there are 77 families, twelve of which contain at least 15 species; most of these more speciose groups are typical from shallow waters (e.g., Tellinoidea and Veneroidea) and/or have been reviewed taxonomically (Nuculanoidea and Cuspidarioidea). There are 368 species which live exclusively on the continental shelf, 86 are only known from deep water and 68 species have a wide bathymetric distribution. More than half of the 368 continental-shelf species have a wide geographic distribution; 40 species are exclusive to the Brazilian province, the others also occur in the Caribbean and/or Argentine shelf waters; those from the Caribbean need more investigation. Important knowledge gaps remain for Brazilian Galeommatoidea and Nuculoidea, deep-sea species of Mytilidae, Teredinidae, and Arcidae; the Poromyidae, Limopsidae, Propeamussiidae, and Thyasiridae appear to be underrepresented. Compared to 29 world regional faunas of marine bivalves, the Brazilian diversity ranks in the ninth position.
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The species Mulinia lateralis (Say, 1822) is native to the western North Atlantic Ocean and was first documented in European coastal waters in 2017. Since then, M. lateralis was reported several times in large abundances in the coastal waters of the Netherlands, Belgium, and more scattered in Germany. While the introduction vector is still unclear, we assume that dispersal in the southern North Sea is driven by larval drift related to anti-clockwise residual tidal currents. To test this hypothesis and to document its current status in the central Wadden Sea, individuals were sampled systematically from intertidal flats along 10 transects ranging from the outer Ems River estuary in the west to the outer Elbe River estuary in the east (German North Sea coast) between February and May 2022. In total, 897 specimens of M. lateralis were sampled from 392 stations (mean abundance 2.3 ± 5.0 ind./m ² ). The shell length ranged between 4.0 and 23.6 mm. Regarding the increasing number of records of M. lateralis at multiple sites in Europe since 2017 and based on the data of this study, the species can be considered as established in the western and central Wadden Sea.
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The species Mulinia lateralis (Say, 1822) is native in the western North Atlantic Ocean and was first documented in European coastal waters in 2017. Since then, M. lateralis was reported several times in large abundances in the coastal waters of the Netherlands, Belgium and Germany. While the introduction vector is still unclear we assume that further dispersal in the southern North Sea will be driven by larval drift related to anti-clockwise residual tidal currents. To report its current distribution status in the central Wadden Sea, individuals were collected systematically from intertidal flats along 10 transects ranging from the outer Ems River estuary to the outer Elbe River estuary (German North Sea coast) between February and May 2022. In total, 897 specimens of M. lateralis were sampled from 392 stations (mean abundance 2.29 ± 4.97 ind./m²). The shell length ranged between 3.98 and 23.55 mm thus representing at minimum two cohorts. Regarding the increasing number of records of M. lateralis at multiple sites in Europe since 2017, the species can be considered as established in the western and central Wadden Sea.
Article
This datasheet on Chama macerophylla covers Identity, Overview, Distribution, Dispersal, Diagnosis, Biology & Ecology, Impacts, Uses, Prevention/Control, Further Information.
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This datasheet on Teredo navalis covers Identity, Overview, Distribution, Dispersal, Diagnosis, Biology & Ecology, Environmental Requirements, Natural Enemies, Impacts, Uses, Prevention/Control, Further Information.
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We investigated stratigraphic changes in mollusk death assemblages and geochemistry in sediment cores from four seagrass beds and one unvegetated site in the Gulf of Guanahacabibes (GG), NW Cuba. There was a transition from mangrove to seagrass beds, associated with sea level rise ∼6000 years ago. Sediment accumulation rates during the last century showed a general rise, but increased sharply after ∼1980, likely because of human activities. The GG displayed overall high mollusk γ-diversity, and our estimate of 189 species is biased toward the low end. High β-diversity was driven by inter-site differences in grain size, vegetation cover, and nutrient input. Spatial heterogeneity within the basin influenced downcore abundance and diversity metrics, highlighting the influence of local drivers. Herbivorous gastropods dominated in seagrass beds and suspension feeder bivalves were dominant on sandy bottom. In the top parts of cores, species richness declined at two sites that were subject to high, human-mediated bulk sedimentation rates and eutrophication. Conservation measures are needed to preserve this hotspot of marine diversity.
Article
After decades of study, much remains unknown about the foraging practices of the earliest inhabitants of Puerto Rico. Here, we present an analysis of the malacological assemblages of two neighboring and (partially) contemporary early sites from the island's southwest, finding intriguing intersite differences in shellfish collection practices. We attribute this diversity to differences in site type, chronology, or changes in local coastal configuration. This work not only provides insights into prehistoric Puerto Rican foraging dynamics but also demonstrates the importance of considering factors including intra-age chronology, site type, and changes in paleoenvironmental conditions when considering ancient foraging practices.
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Antecedentes: Los gasterópodos y bivalvos marinos son algunos de los grupos de invertebrados más diversos en la naturaleza, pero en México se requiere de un mejor conocimiento de su composición taxonómica. Aunque existen importantes estudios sobre los moluscos del Caribe mexicano algunas zonas como la isla de Cozumel han sido poco estudiadas. Objetivo: Difundir nuevos registros de gasterópodos y bivalvos marinos de la isla de Cozumel. Métodos: Los ejemplares se recolectaron principalmente a partir de transectos en sustratos arenosos y revisión de superficies rocosas. Resultados: De un total de 51 especies de gasterópodos pertenecientes a 39 géneros y 23 familias, y 11 especies de bivalvos pertenecientes a 10 géneros y nueve familias, se registraron nueve especies como nuevos registros, seis de gasterópodos y tres de bivalvos, lo que incrementa el conocimiento de la malacofauna marina de la región. Los nuevos registros representan el 11.76% y 27.27%, respectivamente, de la fauna total de gasterópodos y bivalvos marinos conocidos en las costas de la isla de Cozumel. La principal afinidad malacogeográfica de los nuevos registros es la Caribeña. Conclusiones: El área de estudio posee el 87.93% de los gasterópodos marinos conocidos para el estado de Quintana Roo. El total de especies de bivalvos marinos del área de estudio constituyen el 13.92% de la fauna de esta clase de moluscos para el estado. Aunque la principal afinidad malacogeográfica de los nuevos registros de moluscos marinos es la Caribeña, el área de estudio pertenece a una zona de transición con la provincia Caroliniana. Ninguno de los nuevos registros es endémico. Todas las especies de gasterópodos y bivalvos indicados como nuevos registros se distribuyen en al menos cuatro subprovincias malacológicas.
Chapter
Mexico harbors several types of coastal ecosystems both in the Atlantic (Gulf of Mexico and Caribbean) and in the Pacific (tropical and subtropical) on which the regional and national socio-economic development depends. They have been studied through several modeling approaches for management, conservation, and necessary ecological studies. In this chapter, we review and synthesize the most recent and relevant studies conducted, with particular emphasis on coral reefs. In the Caribbean, coral reefs are likely the most rapidly changing ecosystems with a net decline in the cover of reef-building corals accompanied by rapid increases of fleshy macroalgae over the last decades. Remaining coral communities are changing toward weedy coral species that are unlikely to support reef growth and thus provide important services to other species and humans. Since 2015 the Mexican Caribbean coast experienced a massive influx of drifting Sargassum spp. that accumulated on the shores, resulting in a build-up of decaying beach-cast material and near-shore murky brown waters (Sargassum-brown-tides), drastically modifying near-shore waters conditions by reducing light, oxygen (hypoxia or anoxia), and pH. The Gulf of Mexico’s coastal ecosystems have also been under significant threats because of human activities, such as gas and oil extraction, pollution, and fishing. Despite numerous studies conducted in the Pacific, biodiversity knowledge is still incomplete, highly biased toward specific habitats, and often narrow in taxonomic and spatial scope. Concurrently, ecological processes that drive biodiversity have been scarcely disentangled. In spite of sub-optimal conditions for coral calcification (lower alkalinity, upwelling, ENSO, high nutrients concentration) some coral reefs thrive in the Pacific. Calcification rate is disrupted with ENSO events (20–50% drop), but it is not correlated to historical changes in sea surface temperature and it might decrease between 15 and 22% due to ocean acidification.
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The anthropogenic transfer of non-indigenous marine species (NIMS) into new areas of the oceans is a key issue. Despite increasing research effort in recent years many fundamental questions remain to be answered before we can effectively manage the issue. One question is whether the greater number of NIMS thus far documented in temperate waters is real or an artefact of fewer surveys being undertaken in tropical environments. Another one is whether poor taxonomic knowledge of the biodiverse tropics hides NIMS that actually occur there. Extensive taxonomic work in three Pacific localities (Guam, northern Western Australia and Singapore) has been collated in previous papers showing that there are relatively few NIMS in these biodiverse environments. The present paper replicates investigations for a low latitude environment in southern Florida in the Atlantic Ocean. The focus area includes the extensive Florida Keys coral reef environment, the southern margin of the Everglades on Florida Bay and the major PortMiami. Only 48 NIMS were identified in a literature-based compilation of 4,615 species; 15 species were represented by isolated records and have not established populations, leaving only 33 NIMS that are established or whose status is unknown. Records for Mollusca, the group with the most species (1,153) in the compilation, were individually researched and taxonomically verified. It is argued that the relative paucity of NIMS is not a straightforward temperature-driven tropical/temperate issue, but instead there are biological factor(s) restricting the ability of NIMS to colonise biodiverse environments compared to less diverse areas.
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Studies based on functional approach seek to understand the ecological roles developed by species as well as their interactions with the environment in which they are inserted. The hypothesis tested was that functional richness and diversity of molluscan community will be higher at the most complex macroalgal habitat. The study was carried out at Casqueira river estuary (Rio Grande do Norte, Brazil). Three species of macroalgae were collected—Gracilaria domingensis (Kützing) Sonder ex Dickie 1874, Gracilaria cuneata Areschoug 1854, and Solieria filiformis (Kützing) P.W.Gabrielson 1985—and the composition of seven functional traits of the mollusk fauna associated to the algae was characterized in 22 categories. The highest values of functional richness and diversity were for macroalgae with greater habitat complexity (G. domingensis). Some functional traits were influenced more by macroalgal morphology, like ‘life way,’ feeding strategy, body size, and larval development. Thus, we show that the greatest richness and functional diversity of the communities is related to sites with more complex habitat, sites with more shelter and refuge, and food. This highlights the importance of the quality of habitat for shellfish communities and shows that it can be assessed from the use of a functional approach.
Chapter
Mactrinae is the largest subfamily of this group of bivalves. In the American continent 43 species grouped into ten genera are recognized. In this chapter, the species included in the genera Harvella, Mactrellona, Mactromeris, Mulinia and Rangia are redescribed. The genus Harvella includes the only one living species H. elegans (G.B. Sowerby I, 1825). The genus Mactrellona Marks, 1951 groups four species M. alata (Spengler, 1802), M. clisia (Dall, 1915), M. exoleta (Gray, 1837) and M. subalata (Mörch, 1861). The genus Mactromeris Conrad, 1868 includes the Pacific species M. catilliformis (Conrad, 1867), M. hemphillii (Dall, 1894a) and M. polynyma (Stimpson, 1860). The genus Mulinia is one of the most represented ones with nine living species in the American continent. They are M. bicolor Gray, 1837, M. byronensis Gray, 1837, M. cleryana (d’Orbigny, 1846), M. edulis (King, 1832), M. exalbida Gray, 1837, M. lateralis (Say, 1822), M. levicardo (E. A. Smith, 1881), M. modesta (Carpenter, 1864) and M. pallida (Broderip and G.B. Sowerby I, 1829). The genus Rangia Des Moulins, 1832 with four living species is the last group revised in this chapter. Rangia (Rangia) cuneata (Sowerby I, 1832, in 1821−1834), Rangia (Rangianella) flexuosa (Conrad, 1840), Rangia (Rangianella) mendica (Gould, 1851) and Rangia (Rangianella) pontchartrainensis (Morrison, 1965) (new combination) belong to this genus.
Chapter
The living species included in the family Anatinellidae Deshayes, 1853 distributed along the American continent are mentioned in this chapter. All American living species belong to the subfamily Kymatoxinae Stenzel and Krause, 1957. Two genera are recognized. The genus Anatina Schumacher, 1817 groups the species A. anatina (Spengler, 1802) and A. cyprinus (Wood, 1828). And the genus Raeta Gray, 1853 includes R. (Raeta) plicatella (Lamarck, 1818) and R. (Raeta) undulata (Gould, 1851).
Chapter
In this chapter the species included in the genera Simomactra, Spisula, Standella, Trinitasia and Tumbeziconcha are redescribed. The genus Simomactra Dall, 1894d includes three Pacific species: S. dolabriformis (Conrad, 1867), S. falcata (Gould, 1850) and S. planulata (Conrad, 1837). Spisula is another genus with several living species mainly distributed in temperate to cold waters in the north and south regions of the continent. This genus groups the species S. fuegiensis (E. A. Smith, 1905), S. guidoi (Signorelli and Scarabino, 2010), S. isabelleana (d’Orbigny, 1841), S. marplatensis (Doello Jurado in Carcelles, 1949), S. petitii (d’Orbigny, 1841), S. williamsi (Berry, 1960), S. (Hemimactra) solidissima (Dillwyn, 1817) and S. (Hemimactra) raveneli (Conrad, 1832). The genus Standella Gray, 1853 with eight species is another group well represented in American marine waters. It includes the species S. (Standella) fragilis (Gmelin, 1791), S. (Standella) nasuta (Gould, 1851), S. (Micromactra) angusta (Reeve, 1854a), S. (Micromactra) californica (Conrad, 1837), S. (Micromactra) janeiroensis (E. A. Smith, 1915), S. (Micromactra) surinamensis (Altena, 1968), S. (Mactroderma) isthmica (Pilsbry and Lowe, 1932) and S. (Mactroderma) velata (Philippi, 1849). The genus Trinitasia Maury, 1928 with T. iheringi (Dall, 1897) and the genus Tumbeziconcha Pilsbry and Olsson, 1935 with T. goniocyma (Pilsbry and Lowe, 1932) and T. thracioides (Adams and Reeve, 1850) complete the chapter.
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Members of the small bivalve family Cyrenoididae inhabit brackish waters of the eastern and western Atlantic Ocean. Cyrenoida floridana (Dall, 1896) from the western Atlantic is poorly known aside from shell descriptions. A detailed shell and anatomical study of C. floridana is here presented and compared with available data for Cyrenidae and Glauconomidae, two families of closest relationship according to recent phylogenetic studies. The species is characterized by valves externally covered by thin light brown periostracum; muscle scars and pallial line (without sinus) weakly impressed on the internal shell surface; a unique hinge pattern composed of cardinal and lateral teeth joining each other, right hinge with two laterals and two cardinals forming two inverted-V-shaped teeth and left hinge with two cardinals and one lateral forming a horizontal reversed F-shaped tooth; and microtubules inside the shell walls. Anatomically, the species presents unequal adductor muscles; demibranchs fused to each other along their posterior ends; a pair of totally fused, pigmented siphons; two pairs of siphonal retractor muscles; and a stomach with conjoined style sac and intestine, a single typhlosole, and three sorting areas. Evidence of shell parasitism is described.
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Resumo-A poliploidia é uma alternativa para melhorar o desempenho zootécnico e é amplamente empregada na aquicultura mundial. No Brasil, o emprego de técnicas de poliploidia em moluscos, em escala comercial, limita-se a espécie exótica de ostra Crassostrea gigas. O objetivo deste estudo foi avaliar a sobrevivência após aplicação de protocolos de indução à triploidia em Anomalocardia brasiliana através de agentes químicos, como Citocalasina B (CB) e 6-Dimetilaminopurina (6-DMAP), e métodos físicos, por choque térmico frio e choque hiposmótico. A indução à triploidia por CB foi realizada a 1 mg. L-1 , enquanto que a 6-Dimetilaminopurina a 450 µmol.L-1. As induções por choque térmico frio foram realizadas a 2, 5 e 7°C, e as induções por choque hiposmótico a 12‰ de salinidade. As induções químicas à triploidia apresentaram baixa sobrevivência larval após as primeiras 24 horas, diferentemente dos tratamentos físicos, que obtiveram mais de 90% de sobrevivência, assim como o tratamento controle. Estes resultados demonstram que os tratamentos físicos neste período são menos agressivos aos ovos e larvas. Porém novos estudos deverão ser realizados, a fim de aprimorar os protocolos para obtenção de poliploides para espécie. Palavras-chave: Molusco bentônico; manipulação cromossômica; tratamentos físicos. SURVIVAL AFTER INDUCTION TO TRIPLOIDIA IN ANOMALOCARDIA BRASILIANA (VENERIDAE) THROUGH CHEMICAL, HYPOTONIC AND THERMAL TREATMENT Abstract-Polyploidy is an alternative to improve zootechnical performance and is widely used in aquaculture worldwide. In Brazil, the use of polyploidy techniques in molluscs, in commercial scale is limited to exotic specie of Crassostrea gigas. The objective of this study was to evaluate survival after application of triploidy induction protocols in Brazilian anomaly by means of chemical agents, such as Cytochalasin B (CB) and 6-Dimethylaminopurine (6-DMAP), and physical methods by cold thermal shock and shock hyposmotic Induction to triploidia by CB was performed at 1 mg. L-1, whereas 6-Dimethylaminopurine at 450 μmol.L-1. Induction by cold thermal shock was performed at 2, 5 and 7 °C, and the inductions by hyposmotic shock at 12 ‰ of salinity. The chemical inductions to triploidia showed low larval survival after the first 24 hours, unlike the physical treatments, who obtained more than 90% of survival, as well as the control treatment. These results demonstrate that the physical treatments in this period are less aggressive to eggs and larvae. However, new studies should be carried out in order to improve the protocols for poliploid species.
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A poliploidia � uma alternativa para melhorar o desempenho zoot�cnico e � amplamente empregada na aquicultura mundial. No Brasil, o emprego de t�cnicas na escala comercial limita-se a uma esp�cie ex�tica de ostra Crassostrea gigas. O objetivo deste estudo foi avaliar a sobreviv�ncia ap�s aplica��o de protocolos de indu��o � triploidia em Anomalocardia brasiliana atrav�s de agentes qu�micos, como Citocalasina B (CB) e 6 - Dimetilaminopurina (6-DMAP), e m�todos f�sicos, por choque t�rmico frio e choque hiposm�tico. A indu��o � triploidia por CB foi realizada a 1 mg. L-1, enquanto que a 6-Dimetilaminopurina a 450 �mol.L-1. As indu��es por choque t�rmico frio foram realizadas a 2, 5 e 7�C, e as indu��es por choque hiposm�tico a 12� de salinidade. As indu��es qu�micas � triploidia apresentaram baixa sobreviv�ncia larval ap�s as primeiras 24 horas, diferentemente dos tratamentos f�sicos, estes obtiveram mais de 90% de sobreviv�ncia, assim como o tratamento controle. Estes resultados demonstram que os tratamentos f�sicos neste per�odo s�o menos agressivos aos ovos e larvas. Por�m novos estudos dever�o ser realizados, a fim de aprimorar os protocolos para obten��o de poliploides para esp�cie.
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Con el presente libro, de corte científico divulgativo, nos proponemos hacer una síntesis de toda la información científica disponible sobre los moluscos marinos de la península de Guanahacabibes, con la necesaria actualización taxonómica y el completamiento de las listas de especies, llevadas en esta ocasión hasta un total de 1000, sin pretender que este inventario sea todavía concluyente.
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A new genus, Clathrolucina Taylor and Glover, is proposed for the widely distributed western Adantic species Lucina costata d'Orbigny, 1846, which has previously been placed in Codakia, Ctena, and Parvilucina. Molecular evidence indicates a closer relationship to Radiolucina and Lucinisca. A new species, Ferrocina garciai Taylor and Glover, is described from submerged pinnacles off the coasts of Louisiana and Alabama. It is similar to Ferrocina species described from the western Pacific and, in molecular analysis clusters, with Parvilucina and Bathyaustriella. Unusual features of this species include the large ctenidia and the lateral coiled pouches of the visceral mass. A neotype is designated for Lucina orbiculata Montagu, 1808 aka Ctena orbiculata, an abundant shallow water lucinid of the western Adantic. The original type material is missing, the type locality is erroneous and considerable doubt exists about the identity of this species.
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This study provides both a current taxonomic listing of known species of marine bivalves from the coast of Tamaulipas, Mexico as well as an overall assessment of their poorly known biogeographical relationships. Marine bivalves were surveyed (midlittoral, supralitoral and sublittoral zones) from September 1987 to April 2010. One hundred and thirtyone species of marine bivalves representing 98 genera in 37 families are reported. Two species are f irst records for Tamaulipas. These 131 species share the following malacogeographical relationships: 62 species (47.32%) exhibit Caribbean and Carolinian affinities, 20 species (15.26%) exhibit Carolinian and Caribbean affinities, 13 species (9.92%) exhibit Carolinian and Argentinean affinities and 12 species (9.16%) exhibit Caribbean, Carolinian and Boreal affinities. Only 6 species (4.58%) exhibit an exclusive Caribbean distribution and 4 species (3.05%) are known only from the Gulf of Mexico. The fact that 81.66% (107 species) of the marine Tamaulipan bivalve fauna exhibits the above malacogeographical relationships provides overwhelming evidence that the Tamaulipan coast of Mexico represents a transitional zone between the Carolinian and Caribbean malacological provinces.
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To broaden the anatomical knowledge of marine bivalves, detailed gross anatomical studies of 20 species from the Florida Keys are presented, representing 19 families: (Cardiidae) and Scissula similis (J. Sowerby, 1806) (Tellinidae). These taxa represent various clades of the class Bivalvia and interface with broader regional and phylogenetic studies (e.g., the Bivalve Tree of Life, http://www.bivatol.org, and Bivalves-in-Time-and-Space, http://www.bivatol.org/bits), in which many serve as exemplar species in different contexts. These descriptions provide the most complete anatomical descriptions yet presented for all species, most especially for Solemya occidentalis, Limopsis aff. cristata, Hyotissa mcgintyi, H. hyotis, Carditamera flori-dana, Entodesma beana, Chama macerophylla and Polymesoda floridana, for which no or only minimal anatomical information has been previously published. This work presents the first anatomical description of any species of Scissula, based on S. similis. Two controversial characters – the promyal passages (in Hyotissa spp., in Anomia simplex noted here for the first time, and in Crassostrea reported in the literature) and the various kinds of posterior apertures and siphons present in the species examined and across the Bivalvia – emphasize the need for further comparative study to confirm homologies. Conspecificity of Brazilian material with that from the North American coast is clarified for all species, resulting in nine species being removed from Brazilian checklists (S. occidentalis, B. exustus, I. alatus, P. carnea, C. floridana, C. macerophylla, L. hians, L. serratum, and S. similis). Pertinent anatomical characters are summarized in a data matrix, and an analysis is provided to demonstrate the utility and resolving power of such characters (but from this limited taxon sampling is not intended to provide a revised phylogenetic hypothesis of bivalve relationships); data for three additional species from Florida, published earlier, are included in the analysis and discussion.
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Recent work with RAPD DNA markers (Adarakewicz and Harasewych, 1994) revealed the absence of fixed differences between the subspecies Donax variabilis variabilis Say, 1922, and D. variabilis roemeri Philippi, 1849, confirmed that D. parvulus Philippi, 1849, is distinct from D. texasianus Philippi, 1847, and established that D. parvulus is more closely related to D. variabilis than to D. texasianus, which it otherwise resembles. A fresh examination of RAPD markers in the remaining two Carolinian nominate species has shown that D. fossor Say, 1822, is indistinguishable from D. parvulus for all markers studied. As the name D. fossor has priority, D. parvulus should be considered its synonym. Similarly, D. dorotheae Morrison, 1971, was indistinguishable from D. texasianus, and should therefore be placed in the synonymy of D. texasianus. Thus, the biogeography of Donax is considerably simplified. D. variabilis, the larger, more intertidal species, occurs on both the Atlantic and Gulf coasts. Its division into two subspecies separated by the mouth of the Mississippi River cannot be justified based on RAPD data. D. variabilis shares each coast with a smaller, subtidal species, D. fossor on the Atlantic coast and D. texasianus in the Gulf of Mexico, with the Florida peninsula separating the subtidal species. We suggest that the emergence of Florida during the Cenozoic served as a barrier that led to the differentiation of D. fossor and D. texasianus. D. variabilis apparently evolved as an offshoot from D. fossor and subsequently entered the Gulf of Mexico, perhaps when it was connected to the Atlantic by the Suwanee Strait.
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In 1999, the green mussel, Perna viridis, was first observed in Tampa Bay, Florida. This was the first reported occurrence of this Indo-Pacific marine bivalve in North America. The mussels found in Tampa Bay were confirmed to be P. viridis based on both morphological and genetic characteristics. Since the initial discovery, surveys in Tampa Bay and on the west coast of Florida have documented the growth, recruitment, and range expansion of P. viridis. From November 1999 to July 2000, the mean shell length of a Tampa Bay population increased from 49.0 mm to 94.1 mm, an increase of 97%. Populations of P. viridis are successfully reproducing in Tampa Bay. Recruitment was observed on sampling plates in May and continued through July 2000. The full extent of mussel colonization is not clear, but mussels were found outside Tampa Bay in St. Petersburg, Florida, south to Venice. Based on these studies it is evident that P. viridis has successfully invaded Tampa Bay and the west coast of Florida. The long-term impact of P. viridis on native communities off the west coast of Florida cannot be predicted at this time.
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The technical report that served as a draft manuscript for the book "Reefs and Banks of the Northwestern Gulf of Mexico" 1985.
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Literature data contributing to a biodiversity survey of bivalve species of the Florida Keys are presented in the form of 361 annotated references and a documented species list. 389 species are recorded as identified to at least the species level; all except ten species can be traced to at least one literature citation. Thirty-one nominal species-level taxa were originally described from Florida Keys material or had their type localites designated as such. Annotations on synonyms, confirmed or suspected misidentifications, and a discussion of problematic geographic information are included, as tools for accessing and interpreting the full body of literature, including 19th century works and 91 entries of "gray" literature (i.e., non-peer-reviewed reports, newsletters, unpublished dissertations, websites, etc.). This paper provides supporting data for an analysis of the bivalve fauna of the Florida Keys, based on a new database of over 12,000 original, museum, and literature records, included elsewhere in this volume.
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There are four eastern Pacific Ocean species of the genus Sphenia: (1) Sphenia fragilis (H. Adams and A. Adams, 1854), occurs in a variety of nestling situations from the intertidal zone to shallow water, from Santa Barbara County, California, to Guayas Province, Ecuador, and has as synonyms S. fragilis Carpenter, 1857; S. pacificensis de Folin, 1867; and S. trunculus Dall, 1916; as well as the western Atlantic Corbula iheringiana Pilsbry, 1897; and S. antillensis Dall and Simpson, 1901. (2) Sphenia gulfensis, a new species, is restricted to soft bottoms in the Gulf of California. (3) Sphenia hatcheri Pilsbry, 1899, occurs, probably in relatively soft substrata, from Rocha Department, Uruguay, through the Estrecho de Magallanes, as far north as Isla Chiloé, Chile; S. subequalis Dall, 1908, is a synonym. (4) Sphenia luticola (Valenciennes, 1846), occurs offshore in rock cavities from Jefferson County, Washington, to San Diego County, California, and has as synonyms S. pholadidea Dall, 1916; Cuspidaria nana Oldroyd, 1918; and S. globula Dall, 1919. Sphenia bilirata Gabb, 1861, may have been based on Recent specimens of Hiatella arctica (Linnaeus, 1758). Sphenia avoidea Carpenter, 1864, is based on a juvenile Mya, most probably M. arenaria Linnaeus, 1758.
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A survey of marine bivalve biodiversity in the Florida Keys, an island archipelago off southern Florida, was compiled from original collecting, museum specimens and the literature. Assembly of over 6000 records resulted in 325 species, 47% of which can be considered common to abundant in the Keys. This represents a 100% increase over the previously known fauna, largely attributable to critical review of museum specimens. Capture of species occurrences from the literature, especially when non-traditional sources (newsletters, agency reports) are excluded, is shown to be least effective, producing only 44% of the total. Bivalve distributions within the Keys show that the fauna is tropical. One-third of the species are wide ranging along the island chain; however, a latitudinal cline in faunal similarity exists from the Upper Keys southwestwards to Dry Tortugas. The fauna of Florida Bay is the most divergent within the study region and also compared to other, ecologically complex, western Atlantic tropical-subtropical regions. Limited historical records indicate little species turnover in the Keys, although population reductions along the main highway and habitat shifts (from natural to artificial substrata) are evident. These results have implications for biodiversity survey methods and, more locally, for management of the Florida Keys National Marine Sanctuary.
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The common tropical western Atlantic venerid bivalve, Chione cancellata (Linnaeus), is revised on the basis of morphological, morphometric and phylo-genetic analyses of conchological characters. Speci-mens inhabiting waters off the United States and Central America south to Belize comprise a separate species, described originally by Say as Chione elevata. The morphological and morphometric examination of numerous samples of both species supports the sepa-ration, pointing to differences of shell sculpture, hinge morphology and relative size of the pallial cavity. Morphological differences in sculpture suggest differ-ent functional characteristics of the species. A phylo-genetic analysis of all extant species of Chione s.s. fails to resolve the relationship between C. cancellata and C. elevata. The parapatric separation of the two species reflects an ancient division of the tropical/sub-tropical western Atlantic into the northern Caloosahatchian Province and southern Atlantic Gatunian Province. This division dates back to at least the Early Pliocene. The fact that the differences between these two dis-tinct species have been overlooked by systematists for almost 200 years suggests that we should re-examine western Atlantic species with broad geographic distri-butions similar to that of C. cancellata. It also suggests that we should pay closer attention to the taxonomy of common, ubiquitous species.
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A database containing 1,234 records of Corbicula fluminea in Texas was created based on published literature accounts, survey reports by Texas Parks and Wildlife Department, unpublished records from university and museum collections, personal communications and author's data. This invasive, exotic bivalve was first collected in Texas in the Neches River in 1958 and was next found in El Paso in 1964. Initial presence on opposite sides of the state supports invasion occurring from the west and east. Corbicula fluminea has since colonized all major drainage basins in Texas. By 2005, it was known from 162 lotic and 174 lentic waterbodies located in 180 of 257 Texas counties. There was a positive significant correlation between the percentage of invaded waterbodies by reservoir size (Pearson r2 = 0.78) and stream order (Spearman R = 0.65). Corbicula populations were found more often in larger reservoirs and higher-order streams and were usually rare to absent in the smallest. Unless precluded by lack of permanent water or inadequate physicochemical parameters, C. fluminea may colonize most of Texas streams greater than second order and all but the smallest impoundments.
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The taxonomy, anatomy, life habits, and distribution of the three western Atlantic species of Varicorbula are discussed. Varicorbula disparilis (d'Orbigny, 1842) is recognized as valid and widely distributed, based on museum material (including lectotype designation), literature, and new collections (by Shipek grab and otter trawl) from the westernmost Florida Keys. Corbula (or Notocorbula) operculata Phllippi, 1848, the most often applied name to this form, is considered a nomen dubium in the absence of locatable type material; C. limatula (Conrad, 1846) is confirmed as a synonym by examination of type specimens. Anatomy is largely congruent with that previously reported for members of Varicorbula and Corbula. The known geographic range of V. disparilis includes North and South Carolina, Georgia, eastern Florida, through the Gulf of Mexico, the Bahamas, and Yucatan, with unverified records from Virginia and several West Indian islands; it is associated with sand or mud habitats from relatively shallow depths to below 1400 m. Attached epifaunal mollusks associated with the Florida Keys samples suggest that this species lives epibenthically in densities of nearly 400 individuals/m2. Two other Recent western Atlantic members of Varicorbula are recognized as valid, both of which had been previously synonymized by various authors with V. disparilis/limatula/operculata. Provisionally maintained as distinct species based on shell characters are: C. krebsiana C. B. Adams, 1852 (Jamaica and Puerto Rico only), and C. philippii E. A. Smith, 1885 (Bermuda, North Carolina, Florida, Texas, Yucatan, the Caribbean, and Brazil). A revised diagnosis of the genus Varicorbula is presented, based on the type species, V. gibba (Olivi, 1792), and new data for the species studied here. In the context of existing taxonomic definitions, Varicorbula is properly placed in the subfamily Caestocorbulinae (rather than Corbulinae or Caryocorbulinae), a subfamily otherwise known only from the Cretaceous and Eocene.
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Pinctada longisquamosa (Dunker, 1852) is redescribed based on original collections from the Florida Keys, type material, and other museum specimens. Conchological and anatomical features support its transfer from the genus Pteria (originally Avicula) to the genus Pinctada. A unique periostracal structure, with elements corresponding to the individual prismatic structures of the outer shell layer is described and illustrated. Comparison is made between this species and Pinctada imbricata and Pteria colymbus, with which it co-occurs and has often been confounded. Its preferred habitat in Florida Bay is seagrass, often intermixed with macroalgae, to which individuals byssally attach substantially off the silt-laden bottom. Quantitative and qualitative data from Florida Bay populations show fluctuating population densities, from absence to over 300 individuals/m 2 , sometimes within a few months. These pronounced changes could be seasonal and/or influenced by the extremes of high and low salinity that sometimes occur in the Florida Bay estuarine system.
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Recent collections from a shipwreck in ~30 m depth off the Florida Keys recovered an exceptionally large gryphaeid oyster that was identified on morphological grounds as Hyotissa hyotis (Linnaeus, 1758), a common constituent of Indian and Pacific Ocean near-shore faunas. This identification was confirmed by molecular characterisation: the Florida specimen had an almost identical large mitochondrial ribosomal subunit (16S) genotype to that obtained from a western Pacific (Guam) conspecific, differing in only two nucleotide positions that were heteroplasmic in the Guam specimen. Although this species has been variously cited to occur in the western Atlantic, careful examination of these records revealed them to be misidentifications of Hyotissa mcgintyi (Harry, 1985), originally described from south-eastern Florida. Because H. hyotis is much larger than any other regional oyster, it is unlikely to have been overlooked in earlier biotic surveys. It is therefore likely that this specimen, and another recently discovered off West Palm Beach, Florida, stem from a recent undocumented introduction to the western Atlantic.
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Marine file clams of family Limidae d'Orbigny, 1846 (+ Radulidae Adams & Adams), characterised by their often colourful mantle and pallial tentacles and by swimming behaviour, are commonly collected and illustrated bivalves. Based on new material from an extensive Florida Keys biodiversity survey plus museum and literature data, western Atlantic species of Lima Bruguière, 1797 (+ Mantellum Röding; Radula Mörch; Limaria Rafinesque; Austrolima Iredale; Meotolima Oyama) and Ctenoides Mörch, 1853 (+ Divaricolima Rovereto) are revised. Lima includes L. marioni Fischer, 1882 (+ L. lata Smith; lectotype selected), and L. caribaea d'Orbigny, 1842 (lectotype selected), distinguished from eastern Atlantic L. lima (Linné) and other species by shell rib number. Ctenoides includes C. scaber (Born, 1778) (+ Ostrea glacialis Gmelin; L. asperula Lamarck; Limaria asperula Link), C. mitis (Lamarck, 1807) (+ L. tenera Sowerby; L. floridana Olsson & Harbison), C. planulatus (Dall, 1886) (lectotype selected), C. sanctipauli Stuardo, 1982, and C. miamiensis, C. obliquus, and C. vokesi, spp. nov. Species distinctions rely mainly on shell characters, although body colour and ornamentation are confirming in some cases. Diagnostic shell characters at the genus-level are supported by new anatomical characters of the gut and tentacles. Known anatomical data for worldwide Lima and Ctenoides species are summarised within a phylogenetic context.
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Five new species of modioliform mussels in the family Mytilidae are described from material collected at sulfide/hydrocarbon seeps in the Gulf of Mexico. New definitive taxa, placed in the subfamily Bathymodiolinae, include the genus Tamu and the species Tamu fisheri from hydrocarbon seeps on the Louisiana Continental Slope, Bathymodiolus heckerae from brine seeps at the base of the West Florida Escarpment in the eastern Gulf of Mexico, and Bathymodiolus brooksi from the West Florida Escarpment site and from hydrocarbon seeps at Alamin̄os Canyon in the western Gulf of Mexico. An additional two new mussel species, which exhibit combinations of morphological characters unlike any existing mytilid genus but for which molecular data are equivocal, are provisionally placed in the genera Bathymodiolus and Idas, respectively. These are: "Bathymodiolus" childressi from hydrocarbon seeps at Alaminos Canyon and the Louisiana Continental Slope, and "Idas" macdonaldi (in the subfamily Modiolinae) from hydrocarbon seeps on the Louisiana Continental Slope.
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The name Papyridea soleniformis (Bruguière, 1789), as used by most authors, embraces two taxa of marine cardiids found in the tropical Atlantic Ocean. Papyridea lata (Born, 1778) occurs in the western Atlantic Ocean, Caribbean Sea, and Gulf of Mexico. Born's specimen in the Zoologisches Museum, Vienna, labeled as variety "roseo-maculata" (891a), is here designated as the lectotype. Papyridea soleniformis (Bruguière, 1789) is sympatric with P. lata, but also occurs in the eastern Atlantic Ocean. Chemnitz, 1782, Conchylien Cabinet, page 65, plate 6, figures 49 and 50 are designated as the lectotype illustrations. Cardium (Papyridea) spinosum var. turtoni Dall, 1900 is a junior synonym of P. soleniformis.
Article
We investigated the evolutionary relationships of three species of Florida Keys oysters, Parahyotissa mcgintyi, Teskeyostrea weberi, and Ostreola equestris, using nuclear and mitochondrial (mt) phylogenetic trees. Both 28S (nuclear) and 16S (mt) ribosomal gene trees consistently recovered a paraphyletic Parahyotissa in which P. mcgintyi, the type species, was robustly sister to a tip clade containing P. numisma and Hyotissa hyotis. This topology implies that there is no phylogenetic basis for Parahyotissa Harry, 1985, and we therefore recommend that all hyotissinid taxa be returned to the genus Hyotissa Stenzel, 1971. Phylogenetic placement of T. weberi within brooding oyster mt 16S gene trees conclusively demonstrated that it is a distinct ostreinid lineage, lacking any obvious candidate sister species, and falsified the hypothesis that it is a free-living ecomorph of the sponge commensal Cryptostrea permollis. Population-level mt COI sequence analysis of American Ostreola equestris and New Zealand Ostrea aupouria revealed that these two globally disjunct ostreinids, though remarkably close relatives, are reciprocally monophyletic sister taxa. Unlike a large fraction of the Floridian nearshore marine biota, O. equestris shows no evidence of a vicariant phylogenetic break distinguishing Gulf of Mexico and Atlantic populations. Our results imply that its present day Gulf/Atlantic distribution has been achieved by range extension from source Atlantic populations followed by a demographic growth pulse in the new Florida Keys/Gulf of Mexico habitats. Ostreola equestris individuals display an impressive range of shell morphs and coloration, some externally resembling T. weberi, and we present a plate of genotyped individuals that document this diversity.
Article
In July 1999, green mussels were seen for the first time at Tampa Electric Company's (TECO) Gannon Station Power Plant (Gulf of Mexico, Hillsborough Bay portion of Tampa Bay, western coast of Florida) during routine maintenance of the seawater intake system. The mussels were identified as Perna viridis (Linnaeus 1758) based on shell and anatomical characters. This identification has been confirmed by cytological analysis. Perna viridis had previously not been found in the United States or in the Gulf of Mexico. Perna viridis is a native species in the Indian and Pacific Oceans and was discovered in the Caribbean Sea in Trinidad in 1990 and in Jamaica in 1998. The populations are widespread locally and well established; the largest specimen collected was estimated to be 15 months of age. This is the second species of Perna introduced to the Gulf of Mexico, joining Perna perna (Linnaeus 1758), which was discovered in Texas in 1990. Since the initial discovery of Perna viridis in Tampa Bay, range surveys have found it as far north as John's Pass in St. Petersburg, Pinellas County, Florida and as far south as Boca Grande, Charlotte County, Florida.
Article
A study of the distribution of macrofauna and the ecological factors affecting their distribution in the bays and lagoons of the central and south Texas coast has made it possible to formulate a series of criteria for interpreting modern and ancient depositional environments. The observations reported in this paper cover a 7-year period. In addition, some information was available covering a period of 30 years. The central Texas bays are situated in a variable climate, and the faunas reflect long-term changes in rainfall and temperature. Four major environments are recognized on the basis of macro-invertebrate assemblages: (1) river-influenced low-salinity bays and estuaries characterized by Rangia and amnicolids; (2) enclosed bays, dominated by oyster reefs composed of Crassostrea virginica; (3) open bays and sounds characterized by Tagelus divisus, Chione cancellata, and Macoma constricta; and (4) bay and lagoon regions strongly influenced by inlets characterized by a mixed Gulf and bay fauna. Smaller "sub-facies" needing more information for recognition are: (1) bay margins, (2) oyster reefs exhibiting marine influence, (3) bay centers, and (4) shallow grassy bays in the vicinity of inlets. Five assemblages were recognized in Laguna Madre which are related to the physiography of the Laguna Madre: (1) shallow hypersaline area near inlet characterized by forms common to the Gulf and normal salinity bays on the north; (2) open hypersaline lagoon characterized by Amygdalum papyria and other forms attaching to vegetation; (3) enclosed hypersaline lagoon with tremendous numbers of two pelecypods, Anomalocardia cuneimeris and Mulinia lateralis; (4) relatively deep hypersaline bay with clayey substrate with virtually no living macro-invertebrates; and (5) hypersaline lagoon with normal bay influence, occupied by many of the species typical of an open bay plus Anomalocardia and Mulinia. The application of macrofaunal assemblages to the interpretation of older sediments was demonstrated in a study of a series of borings taken in the Rockport area. The macrofaunal evidence indicates that the Rockport bays have undergone at least one marine transgression in the past 9,000 years.
Article
The study of marine life of the Gulf of Mexico has progressed slowly as compared to other regions of the United States. Much of this lack of progress is probably due to the absence of universities in the coastal area, and the absence of large populated centers where marine research would be encouraged. The early work was done by travelers and expeditions from places remote to the Gulf. Only in the present century has there been any attempt to establish marine laboratories on this seaside. Most of these laboratories have been located in rather remote, inaccessible places, and have usually suffered from inattention by the parent institution. In recent years, however, the search for oil, industrial growth of coastal cities, and the development of beach resorts have brought new roads and more people to the coast. During the same time the Gulf fishing industry expanded enormously, and, in value, became the largest fishery of the several important fishing regions of the United States. For instance, according to Fisheries Industries of the United States for 1956, the Gulf coast produced more in pounds and value than the Pacific coast, and more in value than the New England states. This new growth has stimulated a demand for more scientific knowledge of the Gulf and its waters. The scientific study of the Mollusca of the Gulf of Mexico has been carried on in the past in museums far from this region. The bulk of this work has dealt mainly with taxonomy, and even the geographical distribution of most species is poorly known. The writer’s purpose in the present work is to give a brief history of prior work on Mollusca along the Mississippi coast, to identify the species found in the area studied, and to discuss what is known of the distribution, abundance, and habits of many of the species. The work was done at the Gulf Coast Research Laboratory in Ocean Springs, Mississippi, and was carried on concurrently while the writer was engaged in other duties and activities. Most of the specimens were collected near the Laboratory or around Horn and Ship Islands, but both ends of Mississippi Sound received attention, and it is believed that the collections are representative of the entire area. The writer did not attempt to work in fresh water, and limited the marine collections to the area inside a line drawn one mile south of the barrier islands.
Article
Morphometric and genetic examinations (using allozyme electrophoresis) were conducted on two Florida populations of bay scallops, Argopecten irradians (Lamarck, 1819), to investigate the status of the subspecies A. i. taylorae Petuch, 1987. One other Florida population [A. i. concentricus (Say, 1822)] was examined morphometrically. Morphometric examinations emphasized mensural and meristic characters used in previous systematic diagnoses. Morphometric data were analyzed using analysis of variance and principal component analysis. Scallops taken from Florida Bay (putatively A. i. taylorae Petuch, 1987) were smaller but otherwise not morphologically distinct from populations of A. i. concentricus (Say, 1822) from Pine Island Sound and Homosassa Bay, Florida. Mean Nei's modified genetic distance value shows a close relationship between Florida Bay and Homosassa Bay scallops. Neither morphometric nor genetic evidence supports the proposed status of A. i. taylorae as distinct from Florida populations of A. i. concentricus.
Article
The evolutionary history of hard clams has clearly been complex and many aspects remain unclear. The population genetics of hard clams in many ways is unremarkable. These species are wide spread and exhibit relatively little inter-specific divergence, as might be expected in a species that has a high dispersal larval stage. On the other hand, hard clams also exhibit patterns of divergence that indicate that their evolutionary history includes episodes of hybridization that has led to differential patterns of selection and introgression between taxa.
Article
This paper addresses the systematics of Pectinoidea collected in the northeast Atlantic on the Lusitanian seamounts, on Galicia Bank, and on the Meteor group seamounts. There are 21 species recorded, of which three (Parvamussium intuslaevis, Cyclopecten cincinnatus, Cyclopecten vimineus from the Meteor group seamounts) are described as new. A lectotype is designated for Propeamussium lucidum (Jeffreys in Thomson, 1873). Cyclopecten antiquatus (Philippi, 1844) is for the first time recorded alive at 805-1160 m on the Meteor group and Galicia seamounts, and distinguished from the Mediterranean-eastern Atlantic species C. hoskynsi (Forbes, 1844). Bathypecten Schein-Fatton, 1985, is placed in synonymy of Catillopecten Iredale, 1939, and the relevant North Atlantic species accordingly named Catillopecten eucymatus (Dall, 1898) (comb. nov.). The character regarding the development of internal ribs, traditionally considered to diagnose Parvamussium and Cyclopecten, is here shown to conflict with characters of the external sculpture. A large, distorted, bathyal pectinid species from the Meteor group (Plato Bank) is tentatively assigned to Pseudohinnites hemiradiatus (de Folin & Périer, 1887) (comb. nov.). Pseudamussium alicei (Dautzenberg & Fischer, 1897) from Galicia bank is found to intergrade morphologically with P. sulcatum (Müller, 1776), whereas in the Azores P. alicei is not readily separable from P. clavatum (Poli, 1795) in the shallower samples. In the pectinids Delectopecten vitreus (Gmelin, 1791) and Pseudamussium spp., the prodissoconch characters indicate a long planktotrophic development, and thus an ability for long-distance dispersal. The shallow-water pectinids found on the Lusitanian banks, with a prodissoconch indicating a short to moderately long pelagic stage, are found as scarce, empty shells and probably do not form stable populations on the banks. All the Propeamussiidae, and the pectinid Hyalopecten pudicus, have a prodissoconch morphology indicating a reduced planktonic stage, or no planktonic stage at all, but are actually never endemic to a single seamount.Cet article traite de la systématique des Pectinoidea récoltés dans l'Atlantique du nord-est, sur les bancs Lusitaniens, le banc Galice et les bancs du groupe Météor. Il y a 21 espèces répertoriées, dont trois (Parvamussium intuslaevis, Cyclopecten cincinnatus, Cyclopecten vimineus du groupe Meteor) sont décrites comme nouvelles. Un lectotype est désigné pour Propeamussium lucidum (Jeffreys in Thomson, 1873). Cyclopecten antiquatus (Philippi, 1844), est signalé pour la première fois à l'état vivant, entre 805-1160 m sur les bancs du groupe Meteor et sur le banc de Galice, et distingué de C. hoskynsi (Forbes, 1844) de la Méditerranée et de l'Atlantique oriental. Bathypecten Schein-Fatton, 1985, est placé en synonymie de Catillopecten Iredale, 1939, et l'espèce Nord-Atlantique nommée en conséquence Catillopecten eucymatus (Dall, 1898) (comb. nov.). Il est montré que le caractère relatif au développement des côtes internes, traditionnellement considéré comme diagnostique de Parvamussium et Cyclopecten, entre en conflit avec des caractères de la sculpture externe. Une espèce de Pectinidé à coquille déformée, récoltée sur les bancs du groupe Météor (Banc Plato) est tentativement identifiée à Pseudohinnites hemiradiatus (de Folin & Périer, 1887) (comb. nov.). Pseudamussium alicei (Dautzenberg & Fischer, 1897) du banc de Galice présente des transitions morphologiques avec P. sulcatum (Müller, 1776), et aux Açores P. alicei ne se distingue pas clairement de P. clavatum (Poli, 1795) dans les stations les moins profondes. Chez les pectinidés Delectopecten vitreus (Gmelin, 1791) et Pseudamussium spp., les caractères de la prodissoconque indiquent un développement larvaire planctotrophe prolongé, et donc une capacité pour une dispersion lointaine. Les pectinidés côtiers trouvés sur les bancs lusitaniens, qui ont une prodissoconque indiquant une phase pélagique relativement courte, sont représentés par des coquilles vides éparses et ne forment probablement pas de populations stables sur les bancs. La prodissoconque de tous les Propeamussiidae, ainsi que celle du Pectinidé Hyalopecten pudicus, indique une phase pélagique très courte ou absente lors du développement larvaire, mais en fait ces espèces ne sont jamais endémiques d'un seul banc.
Article
Ribbed mussels (232 in all) representing the nominal species Geukensia demissa (Dillwyn, 1817) were collected at nine coastal North American locations (two Pacific, four Atlantic and three Gulf Coast locations) between January 1990 and September 1991, and examined for nine shell characters and for variation at 18 allozyme loci. Two genetically-differentiated groups were identified and called demissa-type and granosissima-type mussles, based on similarity of geographic range to previously recognized subspecies of G. demissa. There was very little genetic differentiation of populations over moderate to large (3000 km) distances along the Atlantic coast (for demissa-type mussels), along the Gulf Coast (for granosissima-type mussels), or between Pacific and Atlantic populations of demissa-type mussles. The two types of mussels were differentiated genetically (Nei's unbiased genetic distance =0.550.20) at a level characteristic of separate species in other molluscan taxa, and to a lesser extent were differentiated morphologically. We recommend that the two types of mussels be treated as separate species within the genus Geukensia: G. demissa (Dillwyn, 1817) and G. granosissima (Sowerby, 1914).
Article
In situ growth rates were determined, using two, 1-yr mark/recapture experiments, conducted between September 1991 and July 1993, for an undescribed mytilid, Seep Mytilid Ia, at three hydrocarbon seep sites in the Gulf of Mexico. The sites are located at depths of 540 to 730m, approximately 2745N; 9130W, and are separated by distances of 6 to 18 miles. These seep mytilids harbor methanotrophic endosymbionts and use methane as both a carbon and energy source. The mussel habitats were chemically characterized by analysis of water samples taken from precisely located microenvironments over, among and below the mussels, using small-volume, interstitial water samplers and the Johnson Sea Link submersible. Substantial differences were found in habital conditions, growth rates, and population structure for the mussels at the three sites examined. The growth rate of these seep mytilids reflects the methane concentration in their immediate habitat. Mussels at sites with abundant methane had growth rates that were comparable to shallow water mytilids at similar temperatures (5 to 8C) with increases in shell length up to 17 mm yr–1 documented for smaller mussels (