No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
A New Deep-Sea Suctorian-Nematode Epibiosis (Loricophrya-Tricoma) from the Blanes Submarine Canyon (NW Mediterranean)
Abstract and Figures
During a pluri-disciplinary study carried out within the frame of the Spanish research project DOS MARES, multicore samples were collected along the Blanes submarine canyon and its adjacent open slope to study the structure and dynamics of the meiofaunal organisms, mainly nematodes. Among the 5808 nematode individuals identified, only 190 of them belonged to the genus Tricoma (Desmoscolecidae), and only two harboured epibiont suctorian ciliates. The three specimens were located near the tail of the basibionts. A careful examination of the ciliates revealed that they were suctorians, which are here described as a new species of Loricophrya, namely L. mediterranea sp. nov. The new species is characterized by having a conical, slightly elongated lorica, narrowing towards posterior end; an anterior end inward curved, surrounding the lorica opening; a body placed near the lorica opening, occupying 1/3 of the lorica length, 4-8 capitate tentacles, and a peripheral, oval to sausage-shaped macronucleus. Our findings represent the first known report of an association with a deep-sea species of Tricoma, and the first record in the Mediterranean Sea, for a species of Loricophrya. The significance of the relationships between suctorian ciliates and their host in extreme environments such as deep-sea submarine canyons is discussed.
Figures - uploaded by Daniel Martin
Author content
All figure content in this area was uploaded by Daniel Martin
Content may be subject to copyright.
... Nematoda is the most abundant, ubiquitous and diverse meiofaunal marine phylum [23] and they cover a key ecological role in the ecosystem processes [24]. Thanks to their cuticle characteristics, often made by a thick and multi-layered collagenous covering, they are ideal basibionts for many suctorian ciliates (e.g., [22,25]). In particular, nematodes of the families Desmodoridae and Desmoscolecidae have found to be largely colonized due to the well-developed cuticular ornamentation that favors the adhesion of epibionts (e.g., [26]). ...
... stresemanni) and on other nematodes that were not identified (L. sivertseni) [25,27]. ...
... At the cuticle level, there is mucus production that characterizes many of the basibiont nematodes. Mucus production and the release of other physiological secretions/excretions enhance the attachment of bacteria and food particles on the basibiont body surface and ciliates may take advantage of this available direct or indirect food source [25]. For instance, the desmoscolecid nematodes, in adults, possess an annulated body cuticle covered with a fine granular substance (which may be a secretion) and imbedded mineral particles and aggregations of bacteria [67]. ...
Epibiosis is a common phenomenon in marine systems. In marine environments, ciliates are among the most common organisms adopting an epibiotic habitus and nematodes have been frequently reported as their basibionts. In the present study, we report several new records of peritrich and suctorian ciliates-nematode association worldwide: from a deep-sea pockmark field in the NW Madagascar margin (Indian Ocean), from a shallow vent area in the Gulf of Naples (Mediterranean, Tyrrhenian Sea), in a MPA area in the Gulf of Trieste (Mediterranean, Adriatic Sea), from a mangrove system in French Guiana (South America, Atlantic Ocean), and from the Maldivian Archipelago. In addition, three new species of Suctorea from the Secca delle Fumose shallow vent area (Gulf of Naples) were described: Loricophrya susannae n. sp., Thecacineta fumosae n. sp. and Acinetopsis lynni n. sp. In the light of these new records and data from the existing literature, we discuss the suctorian-nematode epibiosis relationship as a lever to biodiversity.
... Epibiosis is recorded between the hydrozoan Bimeria vestita and Pelogenia fimbriata, a scaleworm different from other species of the genus by the presence of middorsum lobe of segment II rounded; neurochaetal handles with 0-3 transverse rows of spines, and blades entire or bifid (Pettibone 1997;Cruz-Gómez 2022). This relationship is always between two living organisms, where the epibiont is attached to the body surface of another organism called basibiont and when abiotic and biotic conditions are adequate (Wahl 1997(Wahl , 2008Fernandez-Leborans et al. 2017). The epibiosis between benthic invertebrates and polychaetes has been observed mainly on the dorsal surface (Parapar et al. 2013). ...
The scaleworm Pelogenia fimbriata (Hartman, 1939) collected from Secas Islands, Panama, during the Allan Hancock Pacific Expedition in 1916, was not only recognized as an undescribed species at the time of discovery but has also revealed a new finding almost nine decades after its description. A paratype of P. fimbriata was examined in the Natural History Museum of Los Angeles County, USA and the hydroid Bimeria vestita Wright, 1959 was found attached to an anterior scale of the worm. The interaction between B. vestita and P. fimbriata in this study represents the first record of epibiosis of a hydroid on a sigalionid scaleworm. This discovery contributes to our understanding of epibiosis in Hydrozoa and opens new avenues for further research in this area.
... Epibionts are frequently found at the posterior part of the meiofaunal organism bodies, where the anus-cloaca and the gonopores are commonly present (Lynn et al., 2014;Baldrighi et al., 2020). The release of different physiological secretions and excretions (mucus, dregs, excretory fluids, gametes) enhances the attachment of prokaryotic organisms and food particles on the basibiont, and epibionts could profit from this food source (Fernández-Leborans et al., 2017). Indeed, most of the observed kinorhynch specimens had the epibionts attached to the posterior body end (segments 10-11 and lateral terminal spines), near the anus, or in more anterior regions but frequently linked to structures that produce some kind of secretion/excretion, such as the nephridiopore, the tubes, or the glandular outlets. ...
The Echinoderes coulli-group is characterized by the presence of an enlarged nephridiopore composed of two regions apparently related to increase the osmoregulation efficiency. Representatives of this group are often intertidal species living in habitats with daily salinity changes, including mangroves. In the present study, two new species potentially belonging to this group are described from a lowly polluted mangrove in French Guiana (western Atlantic Ocean). Echinoderes angelae sp. nov. possesses spines in middorsal position on segment 4 and sublateral position on segments 6–7, plus tubes in lateroventral position on segments 5 and 8 and in laterodorsal position on segment 10. Besides, this species has modified type 2 glandular cell outlets throughout different positions on segments 2, 4–8 and 10 and large sensory spots on segment 1 with a transversal row of conspicuously elongated hairs at the posterior part of the papillae area. Echinoderes guianensis sp. nov. has spines in middorsal position on segment 4, lateroventral position on segment 6 and sublateral position on segment 7, plus tubes in lateroventral position on segment 5 and laterodorsal position on segment 10. Also, it lacks modified type 2 glandular cell outlets and large sensory spots with a posterior, transversal row of elongated hairs. These diagnostic features allow the distinction of the new species from the remaining congeners of the E. coulli-group. In addition, the presence of epibionts in some of the examined specimens is discussed.
... Report as epibiont on nematodes Loricophrya mediterranea epibiont on Tricoma sp. was found in the Blanes submarine canyon (NW Mediterranean), 1227-1450 m depth (Fernandez-Leborans et al. 2017). ...
A compilation of the ciliated suctorian species found on marine meiobenthic nematodes as epibiont has been carried out based on published records. It included the taxonomic position of each species of ciliate epibiont, the species of basibiont nematodes, the geographic zones where they have been found and the different records of these species together with the corresponding biblio-graphic references. Altogether 12 suctorian species were listed. Among registered suctorian species, Thecacineta oregonensis, T. urceolata, Trematosoma rotunda, Loricophrya bosporica, L. mediterranea, L. scanica, L. sivertseni, L. spitinae and L. stresemanni are likely specific to nematodes. The species as Thecacineta calix and Limnoricus ceter were found on a variety of hosts. Representatives of the genus Thecacineta reproduce by ver-migemmic budding, swarmers of which are unable to swim, and often attached close to the cloaca of the nematodes. Any regularity in localization were not observed in the representatives of genera Trematosoma and Loricophrya, which form ciliary, swimming swarmers.
... Non-parasitic associations between nematodes and aquatic multicellular animals have been known since 1834, when the marine non-parasitic nematode Odontobius ceti (De Vauzème, 1834) was found on baleen plates (De Vauzème 1834), while associations with unicellular organisms (e.g. suctorian ciliates) have been seldom reported ( Fernandez-Leborans et al. 2017). ...
Several individuals belonging to a new species of the genus Chromadorita (Nematoda: Adenophorea) were collected in a cold-seep area in the Gulf of Guinea during two French cruises: BIOZÄIRE 2 (2001) and BIOZAÏRE 3 (2003–2004) on board the R/V L’Atalante. In this area, rich chemosynthetic benthic communities have been discovered at 3150 m depth in the large pockmark field named Regab. Chromadorita regabi sp. nov. was found among the eggs in ovigerous specimens of the shrimp Alvinocaris muricola. The combination of long size (1500–2200 μm), nine strong preanal papillae and relatively small dorsal tooth with weak musculature distinguishes this species from all known congeneric ones. An identification key to all known species of Chromadorita is provided.
The present article deals with the report of 7 suctorian epibiont species viz. Thecacineta calix, Actinocyathula homari, Loricophrya bosporica, L. cf. stresemanni, Acinetides gruberi, Trematosoma rotunda and Brachyosoma sp. on benthic meiofauna collected from the deep Arabian Sea (> 1000 m). The data on the distribution and host prevalence of found species are discussed. The finds of other deep-sea ciliate species are also mentioned.
Spatial and temporal variations of planktonic copepods were investigated in relation to environmental conditions in the Solis Grande estuary (34°22'S, 55°33'W), Uruguay. Over a period of fifteen days, samples were taken daily at three stations along the main axis of the estuary, and the species composition and abundance were determined. The Solis Grande is a shallow estuary (2.0 m) with no vertical discontinuities. Comparisons of surface versus bottom hydrographic values indicated no vertical stratification of temperature and salinity during the studied period. The species-environmental relationships explain 63.6% of the system's variability considering the two first axes from Redundance Analysis (RA). Copepods showed strong differences in distribution and abundance between stations and successive days. In the region the winds quickly rotate from sectors S-SE (frontal period) to E-NE (post-frontal period). Changes in abundance were significantly related to the inflow and outflow of water produced by the rotation of winds. At smaller space and time scales, the differences highlighted by the RA were the result of wind-forced hydrodynamics after the frontal period. In this situation hydrographic features were dominant (factor one of RA) and wind effects were of secondary importance (factor two of RA). Six species were identified and the estuary was clearly dominated by Acartia tonsa. The results showed two negatively correlated groups: one was integrated by Oithona nana, O. simplex, Paracalanus parvus and P. crassirostris while the second group was integrated by A. tonsa and Euterpina acutifrons. Environmental variability may be responsible for the low diversity.
A suctorian ciliate Thecacineta urceolata sp. nov. is described from the sediment specimens collected in a seagrass bed at Ludao, Taiwan. The suctorian was found colonizing the body surface of nematode Desmodora pontica. The new species differs from relatives, Thecacineta cothurnioides and Thecacineta oregonensis, in the lorica structure, which characteristic by the urceolate apical part.
The suctorian ciliates, Thecacineta cothurnioides and Trematosoma
rotunda, belonging to the families Thecacinetidae and Acinetidae, were
recorded as prominent epibionts on the cuticle of a marine free-living
nematode, Chromaspirina sp. (Desmodoridae) from shallow sediments of
the continental shelf of the Bay of Bengal. The biometrics of these
suctorians are compared with literature data, and their species specific
association with nematodes is discussed.
Three new species of nematodes (Chromaspirina okemwai sp.n., Pseudochromadora interdigitatum sp, n. and Eubostrichus africanus sp. n.) from Ceriops mangrove sediments and one new species (Eubostrichus longosetosus sp. n.) from the North Sea, along the Belgian coast, are described. Chromaspirina okemwai is characterized by four cephalic sensillae and unispiral amphids; Pseudochromadora interdigitatum has unique lateral alae where body annules split into two, three or four smaller ones. Eubostrichus africanus has short (6 mu m) cephalic and subcervical setae and five pairs of strong broad based setae at the tail region; Eubostrichus longosetosus has long (14 mu m) cephalic and subcervical setae, three pairs of strong setae on the tail and two fine ones at the tail tip. Eubostrichus parasitiferus as described by Hopper and Cefalu (1973) is given a new name, E. hopperi sp. n. A revision of the genus Chromaspirina and Pseudochromadora is also included.
Although epibiosis in Crustacea has been well known for a long time, only during recent decades these associations have been considered from various aspects: physiological, evolutionary, ecological, and so forth. Current research has begun to study in detail the processes concerning epibiosis and their effects on the biology of the organisms involved. The aim of this study is to present a general overview of epibiosis in Crustacea, including its ecological importance, adaptations to epibiotic life, specificity of the associations, and other characteristics of epibiont-basibiont interactions. A pesar de que la epibiosis en crustáceos es bien conocida desde hace tiempo, sólo durante las últimas décadas las asociaciones ha sido consideradas desde variados aspectos: fisiológico, evolutivo, ecológico, etc. Desde entonces, se han empezado a estudiar en detalle los procesos concernientes a la epibiosis and sus efectos en la biología de los organismos implicados en este tipo de relación. El propósito del presente estudio es presentar una visión general de la epibiosis en los crustáceos, considerando su importancia ecológica, las adaptaciones a la vida epibiótica, la especificidad de las asociaciones, y otras características de las variadas interacciones epibionte-basibionte.
[An updated inventory of the peritrich (Protozoa, Ciliophora) epibiont species on crustaceans has been carried out. Data concerning 268 epibiont species, their taxonomic position, and the various crustacean basibionts were considered. The overview comprised in this study may be of use in further surveys of protozoan-crustacean epibiosis. Se ha realizado un inventario actualizado de las especies de peritricos (Protozoa, Ciliophora) epibiontes en crustáceos. Se han considerado los datos concernientes a 268 especies epibiontes, su posición taxonómica, y los diferentes crustáceos basibiontes. La visión general que comprende este estudio puede ser utilizada en futuras investigaciones sobre la epibiosis protozoos-crustáceos., An updated inventory of the peritrich (Protozoa, Ciliophora) epibiont species on crustaceans has been carried out. Data concerning 268 epibiont species, their taxonomic position, and the various crustacean basibionts were considered. The overview comprised in this study may be of use in further surveys of protozoan-crustacean epibiosis. Se ha realizado un inventario actualizado de las especies de peritricos (Protozoa, Ciliophora) epibiontes en crustáceos. Se han considerado los datos concernientes a 268 especies epibiontes, su posición taxonómica, y los diferentes crustáceos basibiontes. La visión general que comprende este estudio puede ser utilizada en futuras investigaciones sobre la epibiosis protozoos-crustáceos.]
The present study reports on a range extension of the suctorian species Praethecacineta halacari to the region of He-Ping-Dao, north-east of Taiwan (West Pacific Ocean), Matemwe, the east coast of Unguja, Zanzibar, Tanzania (West Indian Ocean) and Nova Scotia, Canada (West Atlantic Ocean). Praethecacineta halacari is reported here for the first time from Taiwan, Tanzania and Canada. Earlier records include the Caspian Sea, Western Australia, Brazil, India, and various coastal sites in Europe.
Two new species of hydromedusae (Foersteria antoniae and Cunina simplex) are described from plankton collected in sediment traps placed in the Lacaze-Duthiers Submarine Canyon and along Banyuls-sur-Mer coast (northwestern Mediterranean). The Mediterranean hydromedusan deep-water fauna contains 41 species which represent 45.5 % of the world-wide deep-sea hydromedusae fauna (90) and 20% of the total number of Mediterranean hydromedusae (204). The Mediterranean deep-water hydromedusan fauna is characterised by a large percentage of holoplanktonic species (61%), mainly Trachymedusae. Nevertheless, contrary to the general opinion, the percentage of meroplanktonic species is equally high. The most original features of this fauna lies however in the importance of the number of endemic species (22%) and in the fact that the majority of them are meroplanktonic Leptomedusae with a supposed bathybenthic stage. Some of the endemic species could still represent relics of the primitive Tethys fauna having survived to the Messinian crisis. The origin of the Mediterranean deep-water hydromedusan fauna is discussed and a general hypothesis is proposed.
Olshausenstr. 40-60, D-2300 Kiel, Federal Republic of Germany . ABSTRACT. In the marine environment any solid, exposed undefended surface will become fouled. Similarly, fouling may effect numerous species which are able to tolerate a certain degree of epibiosis. In contrast, many others actively maintain t h e ~ r body surface clean of epibionts ('antifouling'). This paper illustrates aspects of the epibiosis/antifouling complex and discusses the omnipresence of fouling pressure, the first stages in the establishment of a fouhng community, the benefits and disadvantages of epibiosis for both epi-and basibionts, and possible anbfouling defense adaptations.
This study examines the prevalence, intensity, abundance, and spatial distribution of fouling bryozoans on 168 blue crabs, Callinectes sapidus, taken from an estuarine environment in the area of Beaufort, North Carolina. Three epizoic bryozoan species were found on the host crabs. These include Alcyonidium albescens Winston and Key, Membranipora arborescens (Canu and Bassler), and Triticella elongata (Osburn). The proportion of blue crabs fouled was 16%. Results indicate female crabs were significantly more fouled than males. This suggests that the prevalence and intensity of bryozoans are dominantly controlled by the migratory habits of the host, since female crabs spend more time in deeper waters of higher salinity where they are more likely to be fouled by bryozoan larvae. The ventral surface was significantly more fouled than the dorsal. The A. albescens colonies were significantly more abundant on the hosts' lateral spines, M. arborescens dominated the subhepatic sector, and T. elongata was most common around the mouth. The costs and benefits of epibiosis are reviewed. The bryozoan/blue crab relationship described here appears to be phoretic. This means there is minimal negative impact on the crab, the relationship is more beneficial to the bryozoans, and there is no special symbiotic relationship between the crab and the bryozoan.
In the aquatic environment, biofilms on solid surfaces are omnipresent. The outer body surface of marine organisms often represents a highly active interface between host and biofilm. Since biofilms on living surfaces have the capacity to affect the fluxes of information, energy, and matter across the host’s body surface, they have an important ecological potential to modulate the abiotic and biotic interactions of the host. Here we review existing evidence how marine epibiotic biofilms affect their hosts’ ecology by altering the properties of and processes across its outer surfaces. Biofilms have a huge potential to reduce its host’s access to light, gases, and/or nutrients and modulate the host’s interaction with further foulers, consumers, or pathogens. These effects of epibiotic biofilms may intensely interact with environmental conditions. The quality of a biofilm’s impact on the host may vary from detrimental to beneficial according to the identity of the epibiotic partners, the type of interaction considered, and prevailing environmental conditions. The review concludes with some unresolved but important questions and future perspectives.
A new species of the genus Dahmsopottekina is described from the Mediterranean Sea. Dahmsopottekina guilvardi sp. nov. was collected from abyssal habitats at a depth range of 2340–2850 m. Like its congeners, the new species has a vermiform habitus, a highly transformed P1 in both sexes and a plough-like rostrum in the female. Dahmsopottekina guilvardi sp. nov. can be distinguished from its congeneric species by the combination of a fused basis and endopodite in P1 of both sexes and the absence of an endopodite in P2–P4 of the female. Dahmsopottekina guilvardi sp. nov. is the second record of a harpacticoid species after its congener D. peruana in which the basis and endopodite of a leg other than the P5, namely the P1, are fused. Furthermore, the new species is the only one among Dahmsopottekina species with a 1-segmented P1 exopodite in the male. Similar to its congeners, D. guilvardi sp. nov. is strongly sexually dimorphic. This is evident through the morphology of most of the cephalic appendages and the reduction of P2–P6 in the female. The results of the present study support the observation that Dahmsopottekina species are sparsely distributed and highly endemic. Nevertheless, our results do not agree with the statement of considerably larger females as the length variability between females is greater than between the two sexes. Despite the morphological characters of the species commensurate with a burrowing mode of life, its presence in sediment traps suggests that D. guilvardi sp. nov. is an active ‘swimmer’.
Suctorian epibionts Thecacineta calix attached on the cuticle of nematodes Desmodora sphaerica and D. pontica are reported here from the deep sea hexactinellid sponge Pheronema sp. from the Andaman Sea (Indian Ocean). The epibiont T. calix is reported here for first time from the Andaman Sea
The properties of the body surface play a crucial role in most interactions of marine organisms. Critical ecological properties such as drag, morphology, uptake and release of radiation and organic matter are linked to the body surface of an aquatic organism. The properties and functions of this interface may be modified substantially by the presence and activities of epibiotic communities. This, in turn, may lead to substantial modulation of the interactions between the organism bearing epiphytes and its environment, with consequences for the relative fitness of the host organism (basibiont) and its interactors, and ultimately, the structure and functioning of the assemblage. Epibiosis may act as an ecological lever via these indirect effects, greatly amplifying or buffering biotic and abiotic stress.
Scant information is available regarding the prevalence and distribution of suctorian ciliates on halacarid mites. However, using this limited information and data from our laboratory on the systematics, biology, ecology and distribution of suctorian ciliates that are epibionts of halacarid mites, we redescribed four suctorian species: Limnoricus ceter (Jankowski), Praethecacineta halacari (Schulz), Thecacineta calix (Schroder) and Acineta sulcata Dons. We also recognized Lissacineta allgeni Jankowski and Thecacineta allgeni (Jankowski) as synonyms of Praethecacineta halacari (Schluz), and Thecacineta laophontis Jankowski and Paracineta moebiusi Kahl as synonyms of Thecacineta calix (Schroder). Many suctorians have been reported, but not properly identified in the halacarid literature. So, we have attempted to identify those suctorians to species level. Lastly, the interactions between the suctorians and their hosts are also discussed and Praethecacineta halacari is also reported for the first time from the Indian coast.
We investigated the natural and anthropogenic drivers controlling the spatiotemporal distribution of the meiofauna in the submarine Blanes Canyon, and its adjacent western slope (NW Mediterranean margin of the Iberian Peninsula). We analyzed the relationships between the main sedimentary environmental variables (i.e. grain size, Chl-a, Chl-a:phaeopigments, CPE, organic carbon and total nitrogen) and the density and structure of the meiofaunal assemblages along a bathymetric gradient (from 500 to 2000 m depth) in spring and autumn of 2012 and 2013.
Epibionts–basibionts interaction is an ecological relationship observed across terrestrial and aquatic environments. Ciliate epibionts associated with meiofaunal organisms are ubiquitous throughout marine ecosystems, but their distribution patterns remain largely unknown in mangrove habitats. We studied the occurrence of ciliate epibionts (peritrichids and suctorians) on meiofaunal organisms in the Sundarbans, the world’s largest mangrove ecosystem, during early monsoon of 2015. The present study revealed that 1.13 % of meiofaunal organisms (18 out of 2744 specimens) were infested by ciliate epibionts. The epibionts were found to be adhered to host organisms belonging to free-living nematodes and harpacticoid copepods. Four different species of ciliate epibionts (Cothurnia nova, Pleurophryodendron sp., Thecacineta cothurnioides and Trematosoma rotunda) were associated with four different host meiofaunal species (Chromaspirina parapontica, Dorylaimposis punctata, Stenhelia sp. and Distioculus sp.) as observed in this study. Among them, the epibionts Cothurnia nova and Thecacineta cothurnioides were found in July 2015, while the other epibiont species were encountered in August 2015. The detailed systematic and host frequency and remarks of each ciliate epibiont have been discussed in this study. To the best of our knowledge, this is the first study which reports ciliate epibionts on meiofaunal basibionts from a mangrove ecosystem in India. Our results indicate that the occurrence of epibionts in a mangrove ecosystem (even a human-disturbed site) could be due to habitat heterogeneity and the nature of anthropogenic disturbance. © 2016 Senckenberg Gesellschaft für Naturforschung and Springer-Verlag Berlin Heidelberg
A suctorian ciliate Loricophrya bosporica sp. nov. is described from the body surface of nematodes of genus Desmoscolex collected in oxic/anoxic boundary of the Bosporus outlet area of the Black Sea. The new species differs from relative species L. sivertseni by development of its body, which takes no more than half, or a third of the lorica length, absence of crown-like projections at the lorica edge as for adhesive disk. From L. tuba new species differs by considerably shorter stylotheca and prevalence to nematode host instead of echinoderms.
The presence of peritrich ciliate epibionts Rhabdostyla sp. and Cothurnia sp. on Syllidae polychaetes is reported here for the first time, including the description of three new species of epibiont ciliates. The protozoans were mainly found at intersegmental furrows, close to parapodial bases of newly collected specimens of Syllis magdalena Wesenberg-Lund, 1962, Syllis sp., Salvatoria sp., and Salvatoria concinna (Westheide, 1974) comb. nov. from Chile, Syllis prolifera Krohn, 1852 from Spain, and Prosphaerosyllis magnoculata (Hartmann-Schröder, 1986) from New Zealand. In addition, epibiont protozoans were found on the dorsal surface, nuchal organs, mouth opening, and anterior cirri of Syllis elongata Day, 1949 from Peru, and the ventral surface of Typosyllis macropectinans Hartmann-Schröder, 1982 from Australia. The discovery of protozoan epibionts on syllid polychaetes has impor-tant taxonomic implications that are discussed here. The presence of papillae that are in fact misinterpreted ciliate epibionts has been considered a valid character to distinguish among species or to erect new species of Syllidae, and thus the real origin of papillae-like structures in polychaetes should be carefully assessed.
We studied the effects of attached peritrich ciliates on the fitness of natural populations of Acartia hudsonica (Pinhey) in Stony Brook Harbor, Long Island Sound. Ciliate infection occurred during late spring, and ciliate load (No. ind. ⁻¹ ) was not related to copepod age, stage, or body size. Simulated in situ experiments conducted throughout the period of abundance of A. hudsonica showed that egg production rate (No. d ⁻¹ ) was positively correlated to ambient water temperature, but negatively correlated to ciliate load. Salinity and the concentration of total or >8–10 µ m Chl a were not significant in explaining the variation in egg production rate. Egg hatching success (%) was not influenced by the infection status (presence or absence) of the female. Infected nauplii had lower survival rates (d ⁻¹ ) compared to uninfected nauplii, but their developmental rates (molts d ⁻¹ ) were not significantly different.
Significantly slower average sinking rates were found for infected adults compared to uninfected adults. Slower sinking rates for infected copepods may have been due to an increase in surface area which increased drag. Infected adults with slower sinking rates may be more susceptible to predation. Our findings show that peritrich ciliates can play a role in the seasonal decline and future recruitment of A. hudsonica.
The compilation of several multibeam data sets unveil for the first time the seafloor of almost the entire northeastern Iberian margin, in the northwestern Mediterranean. This is achieved thanks to an international effort involving mainly Spanish and French research institutions. Submarine canyons, turbiditic channels, landslides and a mid-oceanic valley are the main sedimentary features observed. The size and shape of these features vary throughout the margin. However, the morphometric analysis performed reveals geomorphologic affinities between the features, which form different sectors sharing similar patterns. This suggests the subdivision of the margin in three main segments: North Catalan Margin (NCM), South Catalan Margin (SCM) and Ebro Margin (EM). Which are the main mechanisms controlling the morphological variability between these margins? We propose a not frequently used scale to tackle this question: the mesoscale (from one to several hundred kilometres), which allows a comprehensive, holistic and detailed analysis of the seascaping mechanisms shaping the northeastern Iberia continental margin. Preliminary results suggest that, factors controlling the seascape involve a combination of tectonics, long-term fluvial sediment flux to the margin, sediment grain size and basin depth. Modelling of these morphogenetic relationships will contribute to a better knowledge of the seascape development in mid-latitude siliciclastic margins. Funding for this research was provided by EUROSTRATAFORM (EVK3-CT-2002-00079), EURODOM (HPRN-CT-2002-00212), EUROMARGINS (ERAS-CT-2003-980409), Generalitat de Catalunya GRC grant and a Spanish MECD FPU fellowship (DA).
An inventary of the suctorian (Protozoa, Ciliophora) epibiont species on crustaceans has been carried out. Data concerning 124 epibiont species, their taxonomic position, and the various crustacean basibionts were considered. This study may be of use in further surveys of protozoan-crustacean epibiosis.
The phylum Ciliophora is composed of a large number (>7000; Sleigh, 1989) of organisms characterized by the possession of two key features: nuclear dualism and an infraciliature. These two characteristics and the ability of ciliates to exploit their environment have resulted in a taxon composed of organisms with extreme morphological diversity. Macroorganisms, as well as other microorganisms that share the same environment, will likely be impacted by members of this taxon. The external surfaces of Crustacea provide for a wide array of microenvironments that attract the settlement and growth of algae, bacteria, fungi, and numerous types of protists, including sessile (e.g., cyrtophorids) and sedentary ciliates (e.g., chonotrichs, suctorians, some peritrichs). This “forest”; in turn attracts ciliates with predatory or browsing feeding tendencies (e.g., pleurostomes). Other ciliates have evolved to exploit the temporary presence of host body fluids released or lost during molting (e.g., apostomes). Still other ciliates actively invade crustacean tissues (e.g., other apostomes) or enter through wounds in the exoskeleton (e.g., philasterine scuticociliates). This article reviews the status of ciliate/crustacean relationships by presenting information on the prevalence and distribution of ciliates on crustaceans and the effects that ciliates may have on their hosts.
The relationship between the suctorian Ephelota gemmipara and the large hydroid Eudendrium racemosum from the North Adriatic Sea has been studied over its full annual cycle. Ephelota gemmipara settles on the perisarc of the hydroid, usually close to the hydranths in order to exploit the hydroid's food discharges. The life cycle of E. gemmipara is influenced by temperature variations and by its relationship with the host. The hydroid shows an active phase in the summer, and it gets through the adverse winter season forming resting stages. In April, when temperature increases, the hydroid starts its active phase and it is colonized by suctorians. From May to September the suctorians produce multiple buds (swarmers) that detach from the parental cells to settle on an Eudendrium colony. The abundance of the suctorian peaks in September, with more than 1.2 million ind. m(-2). Their proliferation coincides with the maximal abundance of their host and the highest water temperatures. On the contrary, sexual reproduction and the encystment occur when the temperature and the abundance of E. racemosum decrease. Lastly, we also report the presence of symbionts such as bacteria and the parasitic protozoans Tachyblaston ephelotensis and Enigmocoma acinetarum.
The studied area appears as a major place for dense shelf water (DSW) formation and export towards the deep basin with Blanes and La Fonera canyons as most efficient pathways. These two canyons are so deeply indented on the continental shelf and slope of the northern Catalan margin (Western Mediterranean Sea) that their heads significantly reduce the width of the shelf and interfere with coast and contour parallel sediment transport patterns. This study presents the results of the analysis of swath bathymetry data and parametric seismic reflection profiles showing the detailed morphology and uppermost sedimentary structure of Blanes and La Fonera canyons, with the focus on their heads and adjacent upper courses and shelf. The main aim is to understand their functioning and assess how they influence and respond to the hydrosedimentary processes active in the study area.
Desrnodora cazca is widely distributed in Australia in mangrove mud-flats. Observations are made on its morphology by light and scanning electron microscopy. Its population density and distribution have been studied in a localised area on the Clyde River estuary in S.E. New South Wales, Australia. Quite large fluctuations were observed over the course of several years but at any one time its distribution within the mangroves was fairly uniform. It reproduces throughout the year. Estimates are given of its biomass, carbon and nitrogen content and oxygen consumption per m2. In laboratory culture it requires particles less than 200 μm and reproduces when fed with the diatom Cylindrotheca sp. Supplying this diatom labelled with [14C]methylglucosc shows that these diatoms are food for D. cazca.
The presence of suctorian ciliates attached to the cuticle of heavily ornamented free-living marine nematodes, especially the family Desmodoridae, has been reported. Observations of nematode hosts and their attached ciliates were made from samples extracted from very fine muddy sands of tropical Australian sea grass meadows. Measurements of the point of attachment of the ciliates revealed that they tend to position themselves near the anus/cloaca of the nematode host.
Fernandez-Leborans, G. and von Rintelen, K. 2010. Biodiversity and distribution of epibiontic communities on Caridina ensifera (Crustacea, Decapoda, Atyidae) from Lake Poso: comparison with another ancient lake system of Sulawesi (Indonesia). — Acta Zoologica (Stockholm) 91: 163–175
The epibiont communities of the shrimp Caridina ensifera, endemic to Lake Poso (Sulawesi, Indonesia), were analysed. Most of the epibiont species were ciliated protozoa belonging to three suctorian genera (Acineta, Podophrya and Spelaeophrya), three peritrich genera (Zoothamnium, Vorticella and Cothurnia), and a haptorid genus (Amphileptus). There was also a rotifer epibiont of the genus Embata. Epibionts were identified to species level. There were 14 to 1114 epibionts per shrimp. The distribution of the epibiont species on the surface of the basibiont was recorded, calculating the number on the different colonized individuals of C. ensifera. The most abundant species, Zoothamnium intermedium and Acineta sulawesiensis, were also the most widely distributed. There was a significant difference between the spatial distributions of the different epibiont species. The analysis of the number of the epibiont species throughout the anteroposterior axis of the shrimp showed a gradient from the anterior to the posterior end of the body. Data from Lake Poso were compared with those of the Malili lake system (Sulawesi), obtained from its endemic shrimp, Caridina lanceolata. Lake Poso had the highest mean diversity, while Lake Mahalona showed the highest maximum diversity. All lakes were correlated with respect to the mean number of epibionts on the anatomical units of the shrimp, which showed a similar general distribution. The distributions of the different epibiont species were compared between the lakes. The possible adaptations of the epibionts as well as the colonization patterns were discussed. From the statistical results and the analysis of the distributions, we propose that in these communities epibiont species have a pattern of colonization in which they follow a behaviour as a whole; each species has a differential distribution, with the species occupying the available substratum with the particular requirements of each functional group, but there is a trend towards maintaining an equilibrium among species and groups, compensating for diversity and number of individuals. In all lakes there was an epibiont distribution model comprising the maintenance of an anteroposterior axis gradient, which was supported by the fluctuation in diversity and number of individuals of the different functional groups of epibiont species. The functional role of the different groups of species seems to tend towards sustainability with little global variation among the lakes.
Sediment traps were placed in the water column both inside and in the vicinity of three northwestern Mediterranean submarine canyons. The sediment traps with 12 rotary collectors were deployed on mooring lines 30 and 500 m above the sea floor, and were sampled fortnightly. Polychaete worms (Anelida) and hydromedusae (Cnidaria) were the most abundant zoological taxa captured. Whereas hydromedusae and three of the polychaete species were clearly planktonic organisms, 16 polychaete species were adult benthic forms without special adaptations for swimming, and sometimes also had a large biomass. Four of the 19 polychaete species are described as new species: Aricidea (Allia) longisetosa sp. nov., Paradoneis hirsuta sp. nov., Ophelina margaleffi sp. nov., and Exogone (Parexogone) canyonincolae sp. nov. The rich collection of polychaetes obtained leads us to postulate that these animals are supported by a continuous flux of organic matter, and that they are adapted to the rigorous physical conditions that may occur between the seafloor and the bottom water. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155, 1–21.
Three previously undescribed species of Hydroidomedusae are described from plankton collected in sediment traps placed in the Foix submarine canyon off the Catalan coast near Barcelona. This rich collection of medusae leads us to postulate the presence of an unusually prolific plankton community in this canyon which is probably supported by a continuous flux of organic matter from the continental shelf, particularly during spring. Foersteria araiae sp. nov. and Teclaia recincolae gen. et sp. nov. were common at 1200 m; a single specimen of Barcino foixensis fam., gen. et sp. nov. was also collected at this depth this depth. The collection of 14 well preserved specimens of Ptychogastria asteroides has allowed the redescription and reillustration of this uncommon species. These four species, together with five specimens of other medusae were found over the course of 1 year of sampling.
Mature females ofDesmodora schulzi Gerlach carry a massive sediment agglutination on the ventral side of their body. Males and juveniles are devoid of the agglutination.
It is suggested that this structure, exhibiting a microbe population in some specimens, is either related to some kind of
unknown maternal brood-care or provides the reproductive female with extra food necessary for the generation of the large
oocytes.
The compilation of several multibeam data sets unveils for the first time the seafloor of almost the entire northeastern Iberian margin, in the northwestern Mediterranean Basin. This is achieved thanks to an international effort involving mainly Spanish and French research institutions. Submarine canyons, turbiditic channels, landslides and a mid-oceanic valley are the main sedimentary features observed. The size and shape of these features vary throughout the margin. However, the morphometric analysis performed leads to the subdivision of the margin in three main segments: North Catalan Margin (NCM), South Catalan Margin (SCM) and Ebro Margin (EM). We address a non-frequently used scale to tackle the question of which are the main mechanisms controlling the morphological variability between these margins. This is the mesoscale (from one to several hundred kilometres), which allows a comprehensive, holistic and detailed analysis of the seascaping mechanisms shaping the continental margin of northeastern Iberia. Preliminary results suggest that factors controlling the seascape involve a combination of tectonics, long-term fluvial sediment flux to the margin, sediment grain size, basin depth and slope gradient. Modelling of these morphogenetic relationships will contribute to a better knowledge of the seascape development in mid-latitude siliciclastic margins.
We performed a multidisciplinary study characterizing the relationships between hydrodynamic conditions (currents and water masses) and the presence and abundance of the deep-water rose shrimp Aristeus antennatus in a submarine canyon (Blanes canyon in the NW Mediterranean Sea). This species is heavily commercially exploited and is the main target species of a bottom trawl fishery. Seasonal fluctuations in landings are attributed to spatio-temporal movements by this species associated with submarine canyons in the study area. Despite the economic importance of this species and the decreases in catches in the area in recent years, few studies have provided significant insight into the environmental conditions driving shrimp distribution. We therefore measured daily A. antennatus catches over the course of an entire year and analyzed this time series in terms of daily average temperature, salinity, mean kinetic energy (MKE), and eddy kinetic energy (EKE) values using generalized additive models and decision trees. A. antennatus was captured between 600 and 900 m in the Blanes canyon, depths that include Levantine Intermediate Water (LIW) and the underlying Western Mediterranean Deep Water (WMDW). The greatest catches were associated with relatively salty waters (38.5–38.6), low MKE values (6 and 9 cm2 s−2) and moderate EKE values (10 and 20 cm2 s−2). Deep-water rose shrimp occurrence appears to be driven in a non-linear manner by environmental conditions including local temperature. A. antennatus appears to prefer relatively salty (LIW) waters and low currents (MKE) with moderate variability (EKE).
- C Romano
- J Coenjaerts
- M M Fleixas
- D Zúñiga
- A Vanreusel
Romano, C., Coenjaerts, J., Fleixas, M.M., Zúñiga, D., Vanreusel, A., Company, J.B., Martin, D. (2013)
303
Ciliophora, Peritrichia)
- Cothurnia
Cothurnia (Ciliophora, Peritrichia). Zoological Journal of the Linnean Society, 172(2), 265-281.
Morphogenetic mesoscale analysis of the northeastern Iberian margin, NW (Ciliophora: Suctorea) on deep-sea Desmodora (Nematoda) from the Andaman Sea
- A M Calafat
Calafat, A. M. (2006) Morphogenetic mesoscale analysis of the northeastern Iberian margin, NW
(Ciliophora: Suctorea) on deep-sea Desmodora (Nematoda) from the Andaman Sea, Indian Ocean.
Hydrozoan and protozoan epibionts on two de capod species
- G Fernandez-Leborans
- R Gabilondo
Deep-water Hydromedusae from the Lacaze-Duthiers submarine canyon (Banyuls, north-western Mediterranean) and description of two new genera (Guillea and Parateclaia)
- J M Gili
- P Puig
- F Pagès
- A Palanques
- J Boullion
- S Heussner
- JM Gili
Evolution, phylogeny and classification of Suctorea (Ciliophora)
- I V Dovgal