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The Genus Sphenia Turton, 1822 (Bivalvia: Myidae) from Shallow Waters of Argentina

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Guido Pastorino at Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"
Guido Pastorino
María Bagur at Centro Austral de Investigaciones Científicas (CADIC-CONICET)
María Bagur
  • Centro Austral de Investigaciones Científicas (CADIC-CONICET)
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431
THE GENUS SPHENIA TURTON, 1822 (BIVALVIA: MYIDAE)
FROM SHALLOW WATERS OF ARGENTINA
Guido Pastorino* & Maria Bagur
Museo Argentino de Ciencias Naturales, Av. Angel Gallardo 470 3° piso lab. 80 C1405DJR,
Buenos Aires, Argentina
INTRODUCTION
The genus Sphenia was first reported in
southern South America by Pilsbry (1899), who
described Sphenia hatcheri from shallow Pa-
tagonian waters. Later, Castellanos (1965) pub-
lished a short note with comments on the type
material of this species, studied by the late J.
J. Parodiz at the Academy of Natural Sciences
of Philadelphia, USA. Finally, in her catalogue
of marine mollusks from Buenos Aires province
(1970: 279), Castellanos mentioned Mar del
Plata (38°S) as the farthest north distribution of
this species. Coan (1999) published a detailed
review of the Pacic species of Sphenia, includ-
ing some interesting data about two Atlantic
species, S. hatcheri and S. fragilis. Scarabino
& Zaffaroni (2004) and Scarabino et al. (2006)
briey reported and discussed the distribution
of these species in Uruguayan waters.
After an exhaustive study of the intertidal
endolithic fauna of bivalves from Buenos Aires
province, Argentina, new ndings of speci-
mens of Sphenia allow the reillustration and
comparison of these species. In addition, new
distributional ranges are provided.
MATERIAL AND METHODS
Specimens collected from the intertidal sedi-
mentary rock shoal, close to Santa Elena, Bue-
nos Aires province, Argentina (37°51’8.81”S,
57°30’21.65”W), were the core of material
studied. Additionally, all the specimens housed
at the collections of the Museo Argentino de
Ciencias Naturales “Bernardino Rivadavia”,
Buenos Aires (MACN), and Museo de La Plata,
Argentina (MLP) were studied. Scanning elec-
tron microscope images were produced with a
Philips XL30 at the MACN. Most photographs
were taken using a digital camera. All images
were digitally processed with the appropriate
software.
MALACOLOGIA, 2011, 54(1-2): 431-435
*Corresponding author: gpastorino@macn.gov.ar
SYSTEMATICS
Sphenia fragilis
(H. Adams & A. Adams, 1854)
Figures 1–8
Synonyms: (complete list in Coan, 1999)
Tyleria fragilis H. Adams & A. Adams, 1854:
418.
Sphenia hatcheri. Castellanos, 1970: 279 (non
Pilsbry, 1899, partim); Figueiras & Sicardi,
1970: 22, pl. 7, g. 103 (non Pilsbry, 1899).
Corbula iheringiana Pilsbry, 1897: 295, pl. 7,
gs. 24–26; Castellanos 1970: 270.
Sphenia fragilis. Coan, 1999: 105, gs. 2–6, 18,
24; Scarabino et al., 2006: 161; Mikkelsen &
Bieler, 2008: 378, g.
Material Examined: (sp. = complete speci-
mens, otherwise specified). 37°51’8.81”S,
57°30’21.65”W, Santa Elena, Buenos Aires,
16 sp., intertidal (MACN-In 38283); Mar del
Plata, Buenos Aires, 1 sp. (MACN-In 10757);
Miramar, 1 sp. (MACN 8451-15); Miramar, 2
sp. (MACN-In 8451); Miramar, Buenos Aires,
1 sp. (MACN-In 29511); Miramar, 1 left valve
(MLP 2365-2); Río Quequén, Buenos Aires, 3
sp. (MACN-In 29514); Puerto Quequén, 1 sp.
(MACN-In 19552); 41°12’S–62°54’W, 1 sp., 1
left valve, in 27.4 m depth (MACN-In 20652);
Puerto Militar, Buenos Aires, in 30 m depth, 2
sp. (MACN-In 11142).
Remarks: The specimens studied showed a
considerable variation in shell shape because
of the constraints imposed by their nestling
habit and consequent dependence on the
substrata where the animal grows. Figures 1–5
illustrate specimens in which the height and
length of, right and left valves, are the most
variable feature. The chondrophore, as it was
pointed out by Coan (1999), holds the main
difference between S. fragilis and S. hatcheri.
As it can be seen in Figure 19, the posterior
PASTORINO & BAGUR432
FIGS. 1-8. Sphenia fragilis (H. Adams & A. Adams). FIG. 1: Left valve; FIG. 2: Ventral view of the
same specimen in 1; FIG. 3: Dorsal view of the same specimen in 1; FIG. 4: Left valve; FIG. 5: Left
valve; FIG. 6: Inner view of left valve, tilted to show the chondrophore. Scale bar Figs. 1-5 = 3 mm;
FIG. 7: SEM image of the left valve, right arrow showing a ridge on the anterior margin of chondro-
phore, left arrow showing the posterior ridge of condrophore slightly projected. Scale bar = 200 µm;
FIG. 8: SEM image of right valve showing the hinge area, arrow pointing the anterior cardinal teeth.
Scale bar = 500 µm. All specimens from MACN-In 38283.
SPHENIA IN THE SOUTHWESTERN ATLANTIC 433
FIGS. 9-19. Sphenia hatcheri Pilsbry. FIG. 9: Inner view of right valve; FIG. 10: Outer view of the same
in 9; FIG. 11: Outer view of right valve; FIG. 12: Inner view of the same in 11; FIG. 13: Outer view of
right valve; FIG. 14: Left valve slighly tilted to see the hinge area; FIG. 15: Inner view of the same in 13;
FIG. 16: Inner view of right valve; FIG. 17: Outer view of the same in 16. Scale bar for all specimens
= 1 cm; FIG. 18: Detail of the hinge of right valve; FIG. 19: SEM image of the chondrophore. Scale
bar = 500 µm. All specimens from MACN-In 37986.
PASTORINO & BAGUR434
ridge of the condrophore of S. hatcheri in the
left valve is longer and clearly projecting out of
the ventral edge, whereas in S. fragilis this ridge
is weakly or not projecting (Fig. 7). In addition,
S. fragilis has a distinctive ridge on the anterior
margin of the condrophore (Fig. 7, right arrow).
A larger anterior cardinal tooth in the right valve
of S. hatcheri is another distinguishing feature.
The same tooth is also present in the right valve
of S. fragilis but much smaller and anterior to a
deeply recessed resilifer (Fig. 8, arrow). Also S.
hatcheri is larger than S. fragilis (30.1 mm vs.
12.7 mm according to Coan, 1999).
Coan (1999) cited S. fragilis as occurring
in both eastern Pacic and western Atlantic
oceans. We have studied material from Uru-
guay and Argentina. The distribution range
in both countries covers the entire marine
coast from Uruguay to 41°12’S–62°54’W in
Argentina. Most of the material comes from
the intertidal zone with the exception of two
lots collected at about 30 m depth.
Sphenia fragilis is found usually intertidally
among and under the talus of the Rhodophyta
Corallina ofcinalis. Also, sometimes it is part
of the fauna associated to the byssal laments
of Brachidontes rodriguezii, the most abundant
mytilid forming large banks at the study area.
Living together with S. fragilis is Hiatella meridi-
onalis, another byssate bivalve fairly common
in this habitat; they share the same crevices,
a usual behavior already reported by Yonge
(1951) for Sphenia binghami and Hiatella sp.
from Port Erin, Isle of Man, United Kingdom.
Coan (1999) pointed out the wide distribution
of S. fragilis. This distribution is apparently not
only Recent, as Scarabino & Zaffaroni (2004)
conrmed its presence of S. fragilis in Quater-
nary deposits of Uruguay.
Sphenia hatcheri
Pilsbry, 1899
Figures 9–19
Synonymy: (complete list in Coan, 1999)
Sphenia hatcheri Pilsbry, 1899: 128, pl. 1, g.
5, 6; Carcelles, 1950: 82, pl. 5, g. 94; Car-
celles & Williamson, 1951: 347; Castellanos,
1965: 173–175, pl. 1, gs. 1–8; Castellanos,
1970: 278–279, pl. 25, gs. 9–11 (partim);
Scarabino & Zaffaroni 2004: 11.
Sphenia subequalis Dall, 1908: 422–423; Car-
celles, 1950: 82.
Material Examined: Puerto Deseado, 1 sp.
(MACN-In 17753); 4 km S of Punta Desengaño,
San Julián, Santa Cruz, several valves (MACN-
In 36931); 7.5 km S of San Julián, 1 sp. (MACN-
In 36919); intertidal coast near of Estancia La
Costa, Coyle, Santa Cruz (MACN-In 37986);
Santa Cruz coast between Coyle and Río
Gallegos, 3 sp. (MACN 10125); Santa Cruz,
(MACN-In 29513); Cabo Buen Tiempo, Santa
Cruz, several sp. (MLP 10246); Monte Tigre, S
coast, Río Gallegos, Santa Cruz, 5 left, 1 right
valves (MLP 1681); Monte Tigre, Río Gallegos,
Santa Cruz, 1 sp., 4 left, 2 right valves (MLP
1349); Monte Tigre, Río Gallegos, Santa Cruz,
(MLP 2041); San Sebastián, Tierra del Fuego,
8 sp., 11 left, 9 right valves; (MACN-In 12617);
Punta María, Rio Grande, Tierra del Fuego, 7
sp. (MACN-In 37910); Río del Fuego, Tierra del
Fuego, several sp. (MACN-In 12616); 54°53’S,
68°14’W, Bridges Is., Tierra del Fuego, 1 left,
1 right valves (MLP 12225).
Remarks: According to Coan (1999), based
on Figueiras & Sicardi (1970) and Castellanos
(1970), the distribution in the southwestern At-
lantic is from La Paloma (34°40’S) in Uruguay
to Mar del Plata, in Argentina. Coan (1999)
suggested that these northern records may
represent sporadic recruitment. Along the Pa-
cic coast of South America, S. hatcheri occurs
from Tierra del Fuego to Isla Chiloe in Chile.
We restricted here the distribution on the south-
western Atlantic from Tierra del Fuego to Puerto
Madryn, Golfo Nuevo, Chubut, Argentina, the
latter based on specimens in the ANSP 170466,
reported by Castellanos (1965). No specimens
of S. hatcheri either from Uruguayan or Buenos
Aires province coasts have been found during
our eld work nor in the collections examined.
Those records north of Puerto Madryn cited by
Coan (1999) from the published literature are
here considered as belonging to S. fragilis, as
well as specimens from Mar del Plata, Buenos
Aires province (MACN-In 10757) mentioned
by Castellanos (1970) and repeated by Coan
(1999).
ACKNOWLEDGEMENTS
E. V. Coan (Palo Alto, California, USA) and
F. Scarabino (MNHNM, Montevideo, Uruguay)
made very useful comments that improved an
early version of the manuscript. L. P. Arribas
kindly helped during eld work. We are grateful
to A. Tablado (MACN-In Buenos Aires, Argen-
tina) and C. Damborenea (MLP) for access to
collections under their care. This work benets
SPHENIA IN THE SOUTHWESTERN ATLANTIC 435
with the criticism of two anonymous reviewers.
It was partially supported by the projects PICT
942 from the National Agency for Scientic
and Technical Promotion, Argentina, and PIP
0732 from the Consejo Nacional de Investiga-
ciones Cientícas y Técnicas (CONICET). We
acknowledge funding by CONICET of Argen-
tina, to which GP belong as a member of the
research carrier and MB as fellow.
LITERATURE CITED
ADAMS, H. & A. ADAMS, 1854, Description of
a new genus of bivalve Mollusca. Annals and
Magazine of Natural History (ser. 2), 14: 418.
CARCELLES, A., 1950, Catálogo de los
moluscos marinos de Patagonia. Anales del
Museo Nahuel Huapi (2 extra nueva serie),
8: 41–100.
CARCELLES, A. & S. WILLIAMSON, 1951, Ca-
tálogo de los moluscos marinos de la provincia
magallánica. Revista del Instituto Nacional de
Investigación de las Ciencias Naturales, Cien-
cias Zoológicas, 2: 225–383.
CASTELLANOS, Z. J. A. de, 1965, Nota sobre
“Sphenia hatcheri” Pilsbry (Moll. Pelecypoda).
Revista del Museo de La Plata (Nueva Serie),
Zoología, 8: 173–175.
CASTELLANOS, Z. J. A. de, 1970, Catálogo de
los moluscos marinos bonaerenses. Anales de
la Comisión de Investigaciones Cientícas de la
Provincia de Buenos Aires, 8: 9–365.
COAN, E. V., 1999, The eastern Pacic species
of Sphenia (Bivalvia: Myidae). The Nautilus,
113: 103–120.
DALL, W. H., 1908, Reports on the Mollusca and
Brachiopoda. Bulletin of the Museum of Com-
parative Zoology, 43: 205–487.
FIGUEIRAS, A. & O. E. SICARDI, 1971, Catálogo
de los moluscos marinos del Uruguay parte 6.
Comunicaciones de la Sociedad Malacológica
del Uruguay, 3: 101–130.
MIKKELSEN, P. M. & R. BIELER, 2008, Seashells
of southern Florida: living marine mollusks of
the Florida keys and adjacent regions. Bivalves.
New Jersey, Princeton University Press, Princ-
eton and Oxford, 503 pp.
PILSBRY, H. A., 1899, Littoral mollusks from Cape
Fairweather, Patagonia. American Journal of
Science (ser. 4), 7: 126–128.
SCARABINO, F. & J. C. ZAFFARONI, 2004, Es-
tatus faunístico de veinte especies de moluscos
citadas para aguas uruguayas. Comunicaciones
Zoológicas, Museo Nacional de Historia Natural
y Antropología, 13: 1–15.
SCARABINO, F., J. C. ZAFFARONI, C. CLAVIJO,
A. CARRANZA & M. NIN, 2006, Bivalvos mari-
nos y estuarinos de la costa uruguaya: faunís-
tica, distribución, taxonomía y conservación. Pp.
157–169, in: R. MenafRa, L. RodRíguez-gaLLego,
f. ScaRabino & d. conde, eds., Bases para la
conservación y el manejo de la costa uruguaya.
Vida Silvestre Uruguay, Montevideo, 668 pp.
TURTON, W., 1822, Conchylia Insularum Britanni-
carum. The shells of the British Islands, system-
atically arranged. Nattali, London, 279 pp.
YONGE, C. M., 1951, Observations on Sphenia
binghami Turton. Journal of the Marine Bio-
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Revised ms. accepted 10 May 2011
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Full-text available
  • Oct 2014
Organisms boring into intertidal consolidated sediments generate bioerosion. It is generally unknown, however, whether they can significantly contribute to coastline retraction. In this paper, we describe endolithic communities and estimate bioerosion and physical erosion rates at three southwestern Atlantic intertidal sites (37, 38, and 42A degrees S; Argentina). In the northernmost site, we have also analyzed spatial variation in species richness and abundance as a function of height within the tidal slope, orientation of the rock surface in relation to breaking waves (i.e., facing or not), and rock hardness. The number of species and the combined abundance of individuals from the different species were larger at the low intertidal level but did not differ between surface orientations. The density of chemically boring organisms increased with increasing rock hardness and calcium carbonate content. In contrast, no correlation was found between rock hardness and the abundance of organisms that bore by mechanical means. Endolithic community composition and bioerosion rates differed among the three sites, the latter being higher at the site with the softer substrate. Bioerosion estimates were two orders of magnitude lower than physical erosion estimates at each site. The bivalve Lithophaga patagonica was the species that contributed the most to bioerosion at all these locations. While results suggest that bioerosion contributes little to overall coastal erosion at the three study sites, boring organisms might still facilitate physical erosion by weakening the rock either via chemical or mechanical means. Besides, their apparently inconsequential direct action as bioeroders can have positive consequences for biodiversity via increased habitat complexity.
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... This compilation included all the publications listed in the section "Previous studies on bivalves from the CFR", as well as the original description of all the species reported from the area. Additional information comes from: Aldea and Troncoso (2008), Aldea and Valdovinos (2005), Aldea et al. (2002), Ashton (2007), Buroker et al. (1983), Castellanos (1971), Castilla and Guiñez (2000), Castilla et al. (2005), Cazzaniga (1994), Chaparro et al. (1993), Coan (1988Coan ( , 1997Coan ( , 1999Coan ( , 2000, Dall (1890Dall ( , 1901Dall ( , 1908bDall ( , 1909, del Rio (1997), Dell (1964Dell ( , 1972Dell ( , 1990, Dijkstra and Köhler (2008), Dijkstra and Marshall (2008), d 'Orbigny (1834'Orbigny ( -1847, Grau (1959), Zelaya (2011, 2013), Hanley (1860), Holmes et al. (2005), Huber (2010), Jonkers (2003), Knudsen (1970), Lamy (1906Lamy ( , 1912Lamy ( , 1922Lamy ( , 1931Lamy ( , 1934, Letelier et al. (2003), Linse (1997Linse ( , 2002, Linse and Brandt (1998), Malchus (2006), Marincovich (1973), Marshall (2002), Nielsen and Valdovinos (2008), Ó Foighil et al. (1999), Osorio (2002), Osorio et al. (1983), Pastorino and Bagur (2011), Pérez et al. (2013), Petit (2009), Philippi (1860, Rabarts and Whybrow (1979), Ramorino (1968), Riveros Zuñiga and González Reyes (1950), Signorelli and Alfaya (2014), Pastorino (2011), Simone (2009), Simone and Penchaszadeh (2008), Smith (1885), Stuardo (1960Stuardo ( , 1962, Tarifeño et al. (2012), Toro and Aguila (1996), González (2009), Toro et al. (2005), Trovant et al. (2014), Turner (1966), Urban and Campos (1994), Villarroel and Stuardo (1998), Waloszek (1984), Zagal and Hermosilla (2001), Zelaya (2009), and Zelaya and Ituarte (2004, 2006. ...
Bivalves from the Chilean Fjords Region: Knowns and Unknowns *
Article
  • May 2015
  • AM MALACOL BULL
The Chilean Fjords Region has been regarded as one of the most complex coastal systems of the world, with a high level of mollusk diversity. Contradictorily, bivalves from this region have been recently considered both well and insufficiently known. This study critically evaluates the current state of knowledge on bivalves from the Chilean Fjords Region, by combining information coming from previously published literature, the study of material housed at museum collections, and new data coming from recently collected material. Although a total of 223 species appear listed in the literature for the area, only 81 valid species have documented records, the remaining corresponding to nomina dubia/nuda, synonyms, misidentifications, species complexes or species which were listed for the area, but based on unknown sources. The present study makes evident that, after more than two centuries the knowledge on bivalve diversity from the Chilean Fjords Region still remains at its first stages.
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NEW MOLLUSCAN RECORDS AND PALAEOECOLOGY OF THE LATE PLEISTOCENE MARINE ASSEMBLAGE FROM LA CORONILLA (ROCHA, URUGUAY) /NOVOS REGISTROS E PALAEOECOLOGIA DE MOLUSCOS DA ASSOCIAÇÃO MARINHA PLEISTOCÉNICA DE LA CORONILLA (ROCHA, URUGUAI)
Article
Full-text available
  • Dec 2018
The Late Pleistocene marine molluscan assemblage from La Coronilla is one of the richest Quaternary marine deposit from Uruguay. This contribution represents an update of the bivalve and gastropod species composition of this deposit and includes a palaeoecological analysis of the molluscan fauna. The ecological preferences of the recorded species allowed the reconstruction of the palaeoenvironmental conditions of the eastern Uruguayan coast and the palaeobiogeographic scenario of the area during the Late Pleistocene. The fossil assemblage of La Coronilla contains 91 bivalve and gastropod taxa of which 28 are new to this deposit and 11 are first reported for the Uruguayan Quaternary marine assemblages. The latest are Turbonilla abrupta, Turbonilla cf. farroupilha, Turbonilla brasiliensis, Turbonilla cf. deboeri, Turbonilla penistoni, Turbonilla turris, Olivella defiorei, Eurytellina angulosa, Kellia sp., Paraleptopecten bavayi, and Pandora sp. Almost all recorded species from the assemblage are marine and live in soft bottoms, although hard/consolidated substrate species and microgastropods that live in ecological interaction with other invertebrate taxa were also found. The high percentage of tropical-subtropical species, the absence of cold-water species, and the record of extralimital warm water northern species, adds new evidence for the inference of warmer than present conditions in the Uruguayan coast during the Late Pleistocene.
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Taxonomy of myid bivalves from fragmented brackish-water habitats in India
Article
Full-text available
  • Nov 2018
A group of small bivalves inhabiting Indian brackish-water estuaries and lagoons (known locally as backwaters), variously assigned to Corbula, Cuspidaria, and Sphenia, are reviewed and, based on shell characters, shown to be congeneric. Molecular (COI) and morphological data indicate that this group belongs to the family Myidae. Furthermore, the combined data suggest that these Indian myids are a sister taxon of the genus Sphenia. The Indian material studied herein exhibits a functional morphology typical of infaunal bivalves, whereas typical Sphenia are nestling and epibyssate. A new genus, Indosphenia, is thus erected for the Indian group and includes five species, one of which is named in this study. Indosphenia kayalum Oliver, Hallan & Jayachandran, gen. et sp. n. is described from the Cochin Backwater on the western coast of India. Cuneocorbula cochinensis (Preston, 1916) is transferred to Indosphenia. Additionally, the west coast taxa I. abbreviata (Preston, 1907), I. abbreviata chilkaensis (Preston, 1911) and I. sowerbyi (EA Smith, 1893) are recognised herein. Corbula alcocki Preston, 1907, Corbula gracilis Preston, 1907, Corbula calcaria Preston, 1907 and Corbula pfefferi Preston, 1907 are placed in synonymy with I. abbreviata, and Cuspidaria annandalei Preston, 1915 is synonymised with I. abbreviata chilkaensis.
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Cold, Warm, Temperate and Brackish: Bivalve Biodiversity in a Complex Oceanographic Scenario (Uruguay, Southwestern Atlantic) *
Article
Full-text available
  • May 2015
  • AM MALACOL BULL
The temperate zone of the southwestern Atlantic Ocean (23–42°S), which includes the Patagonian Shelf Large Marine Ecosystem and the Subtropical Convergence Zone, is one of the most productive areas of the Southern Hemisphere. Key features of this region are a wide continental shelf, the convergence of cold and warm currents, and continental freshwater input of the La Plata River. The Uruguayan marine and estuarine waters are at the core of this zone. The marine and estuarine bivalve fauna of Uruguay has received good attention since the publication of the Voyage of Alcide d'Orbigny (1834–1846). Here we provide an overview of taxonomic, faunistic and biogeographic issues, identifying knowledge gaps and highlighting priorities for future research. The main threats for that fauna are discussed, with emphasis on species of current or potential socioeconomic interest. Of the 231 species reported from the area, only four species are strictly estuarine: Erodona mactroides Bosc, 1801, Tagelus plebeius (Lightfoot, 1786), Brachidontes darwinianus (d'Orbigny, 1842) and Mytella charruana (d'Orbigny, 1842). All of these have large biomasses, as is also the case for the marine eurihaline Mactra isabelleana d'Orbigny, 1846. A total of 112 deep-sea species (i.e., living deeper than 200 m) are recorded for the region, including almost every known group occurring elsewhere in deep-sea basins, with the exception of sunken wood associated species. Of these, 38 have been recorded only from the Argentine Basin. Some new records are preliminarily reported and discussed, including Acharax Dall, 1908 (Solemyidae), Lucinoma Dall, 1901, Graecina Cosel, 2006 (Lucinidae), and Callogonia Dall, 1889 (Vesicomyidae), all from the continental slope. A total of 19 warm and warm/temperate bivalve species have their southern distribution boundary in Uruguayan waters associated to warm waters of/or derived from the Brazil Current, including species distributed from the U.S.A. to Uruguay or from southeast Brazil to Uruguay. On the other hand, at least eight exclusively cold-water bivalves exhibit their northernmost distribution boundary off La Plata River; their occurrence there is associated with offshore sub-Antarctic waters. Uruguayan waters represent a critical biogeographical and ecological crossroads because of the complex interaction of currents and water masses. This region is thus particularly well suited as a system for the study of processes underlying biodiversity patterns. Pending challenges in taxonomic and biogeographic research will be successfully addressed only if multinational collaborative initiatives are undertaken in a framework of integrative taxonomy.
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The eastern Pacific species of Sphenia (Bivalvia: Myidae)
Article
Full-text available
  • Dec 1999
  • NAUTILUS
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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Observations on Sphenia binghami Turton
Article
  • Oct 1951
  • J MAR BIOL ASSOC UK
The family Myidae is represented in British seas by the two large and well-known species, Mya arenaria L. and M. truncata L., which burrow deeply into muddy sand and into stiff mud or clay respectively, and by the much smaller Sphenia binghami Turton. Interest in members of this family of Eulamellibranchia was aroused during 1949 when studying two species which are common along the coast of California, namely Platyodon cancellatus (Conrad) and Cryptomya californica (Conrad). These differ most interestingly in habitat. The former bores into soft rocks between tide marks, and the latter, although practically devoid of siphons, burrows deep in the mud of tidal estuaries, always in association with burrows made by various large invertebrates. The species most usually involved is Callianassa californiensis, a large anomuran prawn (McGinitie, 1935). The almost sessile siphons open into the sides of the burrows. Accounts of both species have been prepared for publication in California.
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Nota sobre "Sphenia hatcheri
  • Jan 1965
  • Z J A Castellanos
  • De
cASTELLANOS, Z. J. A. de, 1965, Nota sobre "Sphenia hatcheri" Pilsbry (Moll. Pelecypoda).
Littoral mollusks from cape Fairweather
  • Jan 1899
  • 126-128
  • H A Pilsbry
PILSBRY, H. A., 1899, Littoral mollusks from cape Fairweather, Patagonia. American Journal of Science (ser. 4), 7: 126-128.
Estatus faunístico de veinte especies de moluscos citadas para aguas uruguayas
  • Jan 2004
  • 1-15
  • F J C Scarabino
  • Zaffaroni
ScARABINO, F. & J. c. ZAFFARONI, 2004, Estatus faunístico de veinte especies de moluscos citadas para aguas uruguayas. Comunicaciones Zoológicas, Museo Nacional de Historia Natural y Antropología, 13: 1-15.