Common environmental descriptors of two benthic amphi-atlantic mollusc assemblages

Duas associações de moluscos bênticos litorais foram estudadas em ambos os lados do oceano Atlântico, uma tropical no Rio de Janeiro, Brasil, e outra temperada na Galicia, Espanha, procurando-se por descritores ambientais comuns, a ambas, que pudessem explicar, em macro escala, o porquê de essas associações estarem onde estão. As duas associações apresentam, aproximadamente, a mesma riqueza de espécies, cerca de 150 táxons cada uma. Ambas as faunas malacológicas habitam sedimentos arenosos em profundidades variando entre 2-12 m, na Galicia, e 10-40 m, no Rio de Janeiro. As associações malacológicas foram definidas através de Análise de Grupamento e caracterizadas ambientalmente com a aplicação da Análise Discriminante Múltipla realizada sobre os dados abióticos. Não existem espécies em comum entre as associações estudadas; contudo estes táxons apresentam caracteres fenológicos similares em função de habitarem as mesmas fácies sedimentológicas. Um mesmo conjunto de variáveis ambientais (tamanho médio do grão do sedimento, assimetria, curtose, grau de selecionamento, frações de areias fina e média e a profundidade) foram identificadas por condicionarem a presença dessas associações, sugerindo que possam ter um papel relevante como descritores ambientais gerais.Two benthic mollusc assemblages of the continental shelf on both sides of the Atlantic Ocean, a tropical one in Rio de Janeiro, Brazil, and another, temperate, in Galicia, Spain were investigated, with a view to finding common environmental descriptors which would explain, on a macro-scale, why these assemblages are there. Both of the assemblages concerned show approximately the same species richness, about 150 taxa each. The molluscan fauna of both regions live on sandy sediments. The Galician assemblages are at about 2-12 m depth, while those in Rio de Janeiro are at about 10-40 m depth. Malacological assemblages were defined through Cluster Analysis and Multiple Discriminant Analysis of the environmental data showed that each assemblage has its own environmental space. These assemblages have no species in common, but show the same phenological characters associated with each sedimentological facies. The same set of environmental variables (median sediment grain size, skewness, kurtosis, sorting, fine and medium sand fractions and depth) were selected as controlling these assemblages, suggesting that they play their role as general environmental descriptors

Révision des genres <i>Eulimastoma</i> Bartsch, 1916 et <i>Egila</i> Dall & Bartsch, 1904 (Mollusca, Gastropoda, Pyramidellidae) du Brésil

La taxonomie des espèces des genres Eulimastoma Bartsch, 1916 et Egila Dall &amp; Bartsch, 1904 du Brésil est révisée. Eulimastoma canaliculatum (C. B. Adams, 1850), Eulimastoma engonium (Bush, 1885), Eulimastoma surinamensis Altena, 1875, Eulimastoma didyma (Verrill &amp; Bush, 1900), Eulimastoma aff. didyma, Eulimastoma aff. weberi (Morrison, 1965), “Egila” virginiae Altena, 1975 et “Egila” ektopa n. sp. sont décrites. Un lectotype est désigné pour E. engonium, qui est considéré synonyme plus ancien d’Eulimastoma teres (Bush, 1885), cette synonymie est basée sur la variation du format général de la coquille ; les mentions antérieures de E. weberi sont de mauvaises identifications d’E. engonium. Eulimastoma surinamense, décrit originellement comme une variation d’E. engonium, est considérée ici comme une espèce. Les mentions antérieures d’Eulimastoma humboldti (Weisbord, 1962) sont de mauvaises identifications d’E. didyma qui montre une variation intraspécifique accentuée, principalement dans sa sculpture spirale, et inclut un groupe de coquilles du Brésil à protoconques turriculée, nommées ici Eulimastoma aff. didyma. “Egila” virginiae et “Egila” ektopa n. sp. sont provisoirement inclus dans ce genre. “Egila” ektopa n. sp. se distingue de “E.” virginiae sur le plan de la sculpture axiale et par une coquille de forme particulière et un cordon spiral suprasutural.The taxonomy of the species belonging to the genera Eulimastoma Bartsch, 1916 and Egila Dall &amp; Bartsch, 1904 from Brazil is reviewed: Eulimastoma canaliculatum (C. B. Adams, 1850), Eulimastoma engonium (Bush, 1885), Eulimastoma surinamense Altena, 1975, Eulimastoma didyma (Verrill &amp; Bush, 1900), Eulimastoma aff. didyma, Eulimastoma aff. weberi (Morrison, 1965), “Egila” virginiae Altena, 1975 and “Egila” ektopa n. sp. are recorded. A lectotype is designated for E. engonium, which is considered senior synonym of Eulimastoma teres (Bush, 1885), based on general shell shape variation; previous records of E. weberi from Brazil were based on misidentifications of E. engonium. Eulimastoma surinamense, originally described as variety of E. engonium, is treated as a full species; previous records of Eulimastoma humboldti (Weisbord, 1962) from Brazil were based on misidentifications of E. didyma which shows great intraspecific variation, specially in the spiral sculpture, including a group of shells from Brazil with helicoid protoconchs, herein called E. aff. didyma. “Egila” virginiae and “Egila” ektopa n. sp. are tentatively included in this genus. “Egila” ektopa n. sp. is distinguished from “E.” virginiae by general shell shape, suprasutural spiral cord and pattern of axial sculpture.</p

Turbonilla westermanni Jong & Coomans 1988

Turbonilla westermanni Jong & Coomans, 1988 (Figs. 27­30) Turbonilla westermanni Jong & Coomans, 1988: 129, pl. 46, fig. 671; Odé (1996: 61); Redfern (2001: 150, pl. 67, fig. 624). Type locality: Aruba, West Indies. Type material: Holotype: ZMA 3.87. 107, Aruba, West Indies. K.M. de Jong, coll; paratype: ZMA 3.87. 174. Aruba, West Indies. Additional material examined: ­­Ceará State: MORG 14987, off Ceará State, 17 /iv/ 1968, NOAS coll. [1]; ­­Espírito Santo State: IBUFRJ 8949, off Espírito Santo State, viii/ 1979, NOAS coll. [1]; IBUFRJ 9730, REVIZEE # VV 16 (21 ° 10 ’S, 040° 27 ’W, 27.65 m), 26 /ii/ 1996, [1];.­­Rio de Janeiro State: MZSP 30901, off Bacia de Campos (21 20 ' 49 "S, 0 40 31 ' 18 "W, 23m), [1]; IBUFRJ 2991, off Bacia de Campos, iii/ 1992, AG coll. [1]. Remarks: Turbonilla westermanni Jong & Coomans, 1988 (figs. 27­30) differs from the species discussed earlier by the absence of the wider spiral striae in the middle of each whorl and by its axial ribs, which clearly continue through the base (fig. 30). Turbonilla westermanni also has a yellow spiral band above each suture (figs. 27, 28), which is absent in the other species under consideration. Although the holotype of T. westermanni (fig. 27) has somewhat shouldered whorls, the paratype (fig. 28) and all specimens from Brazil (fig. 29) have a more rectilinear profile.Published as part of Pimenta, Alexandre D. & Absalão, Ricardo S., 2002, On the taxonomy of Turbonilla puncta (C. B. Adams, 1850) (Gastropoda, Pyramidellidae), with the description of a new species from Brazil and remarks on other western atlantic species, pp. 1-16 in Zootaxa 78 on page 11, DOI: 10.5281/zenodo.15593

Turbonilla obsoleta Dall 1892

Turbonilla obsoleta Dall, 1892 (Figs. 18­26) Turbonilla puncta C. B. Adams, 1850, var. obsoleta Dall, 1892: 256; Odé (1996: 51). Type locality: Caloosahatchee River, Florida. Type material: Holotype: USNM 113233. Caloosahatchee River, Florida. Material examined: The holotype and: ­­Pará State: IBUFRJ 10353, AMASSEDS # 3210 (01° 52.45 ’ N / 16,02’ W, 47 m), 12 /v/ 1990, RVCI coll. [5]; MORG 38640, off Salinópolis (27 m), 26 /iv/ 1968, NOAS coll. [2]; ­­Maranhão State: MNHN, Praia da Raposa [2];.­­Pernambuco State: MNHN, Praia do Despacho [4]; MNHN, Praia da Conceição [1]; MNHN, laguna de Suape, Cabo [5]; MNHN, Praia de Maria Farinha [1]; MNHN, off Recife [4]; MNHN, Praia do Despacho, Itaparica [5]; MNHN, laguna de Suape, Cabo [1]; ­­Bahia State: MORG 23912, Abrolhos bank, i/ 1985, MORG team coll. [3]; ­­Rio de Janeiro State; IBUFRJ 3151, Prainha, Arraial do Cabo, 1989, T.Almeida coll. [2]; IBUFRJ 10348, Cabo Frio VII # 6147 (22 ° 53.7 ’S, 041° 50.5 ’W, 50 m), 24 /iii/ 1983, NOAS coll. [1]; IBUFRJ 10347, Prainha, Arraial do Cabo, 1989, T.Almeida coll. [2]. Remarks: Although originally described as a variety of T. puncta, Turbonilla obsoleta Dall, 1892 (figs. 18­26) should be considered a valid species. Dall (1892) distinguished T. obsoleta from T. puncta by the "... feebleness of the spiral sculpture, and especially in the fact that the ribs are not cut abruptly at the periphery... of the last whorl, so that the foveolate character of the interspaces is lost...". However, T. obsoleta has spiral striae more irregularly spaced (fig. 24) than T. puncta. Also, the spiral striae in the base of T. obsoleta (fig. 24) are wider then those in the base of T. puncta. Dall (1892) stated that the degree of expression of the ribs in the base is not constant. We also noted the same variation in specimens of the two species. In T. puncta, there can be obsolete ribs insinuating on the base (fig. 7 ­8, 10, 12), but they are feeble and do not reach the umbilical region. In T. obsoleta, the ribs do continue through the base (fig. 24), reaching the umbilical region in those specimens with a greater number of whorls (not the case of the holotype (fig. 18)). Moreover, T. obsoleta has a larger protoconch diameter, ranging from 269 m to 340 m (mean diameter: 306, n = 13). Turbonilla obsoleta has great deal of variation in the general teleoconch shape, which varies from slightly shouldered to a more rectilinear outline (figs. 18­22). Some of the specimens collected along the coast of Pernambuco State (Northeast of Brazil) are very similar in sculpture to T. obsoleta, but differ in the shell shape, as it is more pupoid (figs. 23, 26).Published as part of Pimenta, Alexandre D. & Absalão, Ricardo S., 2002, On the taxonomy of Turbonilla puncta (C. B. Adams, 1850) (Gastropoda, Pyramidellidae), with the description of a new species from Brazil and remarks on other western atlantic species, pp. 1-16 in Zootaxa 78 on pages 8-10, DOI: 10.5281/zenodo.15593

Turbonilla tupinamba Pimenta & Absalão, 2002, sp. n.

Turbonilla tupinamba sp. n. (Figs. 33­37) Type Locality: off Prainha (22 58 'S, 0 42 00'W), Arraial do Cabo, Rio de Janeiro State, Southeast of Brazil. Type material: Holotype: MNRJ 8944, off Prainha, Arraial do Cabo, Rio de Janeiro State, 1989, T.Almeida coll. Paratypes: MORG 41060 and ANSP 410354, Arquipélago de Santana, Macaé, Rio de Janeiro State, v/ 1993, AG coll.; MZSP 35855, off Cabiúnas, Rio de Janeiro State, 21 /iv/ 1993, AG coll.; MNHN, off Espírito Santo State, 18 /iii/ 1993, Eq. Zoo coll.; ZMA 4.02.0 27, off Piúma, Espírito Santo State, 1993, F.Pitombo coll.; IBUFRJ 8330, off Espírito Santo/Rio de Janeiro States, 26­27 /viii/ 1979, NOAC coll. Additional material examined: ­ Espírito Santo State: IBUFRJ 8561, off Piúma, 1993, F.Pitombo coll. [5]; ­ Rio de Janeiro State: IBUFRJ 8986, Arquipélago de Santana, Macaé, v/ 1993, AG coll. [1]; IBUFRJ 8987, Prainha, Arraial do Cabo, 1989, T.Almeida coll. [1]. Etymology: Tupinambá (“the main political leader”, in the Indian language Tupi) is a generic name of many Brazilian Indian tribes which used to live along the Brazilian coast. Description: Shell white, elongate, with slight pupoid shape. Teleoconch with up to 10 whorls; first 3­4 teleoconch whorls convex in profile, while others whorls somewhat sinuous in profile slightly concave just below suture and slightly convex in anterior half. Protoconch of type A­I, with around 2.5 whorls, oriented 100 o to shell axis. Axial ribs sinuous, slightly opisthocline, not continuing through the base; 7 th whorl with 23 to 28 ribs on, while 8 th whorl 27 to 30. Coastal interspaces about equal to the rib width. Spiral sculpture consists numerous very fine striae. A couple of wider and deeper spiral grooves are present, one just above suture and another, not always present, at middle whorl. Base rounded, with very fine and waved spiral striae; without umbilical fissure. Aperture oval, lightly constricted in the posterior region. Columellar fold absent. Holotype with 10 teleoconch whorls. Dimensions of the holotype: length: 4.9 mm; width: 0.9 mm; protoconch diameter approximately 260 m. in width. Remarks: Turbonilla tupinamba (figs. 33­37) has spiral sculpture very similar to T. puncta and T. deboeri, with the conspicuous wider spiral striae at the middle whorl and above the sutures (fig. 34, 35). The main characteristic that distinguishes T. tupinamba from T. puncta is the outline of the whorls, which are convex in the first three to four whorls of teleoconch (fig. 33, 35) and sigmoid in the remainder (fig. 35), while T. puncta has more regularly rectilinear whorls. In addition, the width of the whorls of T. tupinamba becomes almost constant from the 5 th or 6 th whorl on, giving the shell a more or less cylindrical shape in the latter whorls; in T. puncta, the growth pattern is more regular and the shells are more regularly conical. Turbonilla tupinamba has markedly sigmoid axial ribs with their apical extremities projecting over the sutures (fig. 35). Turbonilla puncta and T. deboeri have more rectilinear ribs with extremities that do not project over the sutures (T. deboeri) or project slightly (T. puncta). Geographic notes: This work presents the first report of T. puncta, T. deboeri, T. westermanni and T. obsoleta at latitudes lower than 12 ° N. In Brazil (fig. 38), all these species are principally represented in the north and northeast coast, but T. deboeri, T. westermanni and T. obsoleta range south to the coast of Rio de Janeiro State (23 ° S). Turbonilla tupinamba, on the other hand, is restricted to the southern coast of Brazil. Rios (1994) reported T. haycocki from the north coast of Brazil, without illustrating a shell from that region, but providing a copy of the illustration in Warmke & Abbott (1962). The synonymy of T. haycocki, T. peilei and T. puncta suggested here gives the latter a large geographical distribution, from Bermuda to the Northeast coast of Brazil. Although the pyramidellid fauna from western Atlantic and that from estern Africa (Aartsen, 1981; Peñas & Rolán, 1997; Schander, 1994) show great similarity in the morphology of the shells of the species, it is not the scope of this work to present a comparison between the two faunas. Such study is a pointer for future researches.Published as part of Pimenta, Alexandre D. & Absalão, Ricardo S., 2002, On the taxonomy of Turbonilla puncta (C. B. Adams, 1850) (Gastropoda, Pyramidellidae), with the description of a new species from Brazil and remarks on other western atlantic species, pp. 1-16 in Zootaxa 78 on pages 11-13, DOI: 10.5281/zenodo.15593

Turbonilla punicea Dall 1884

Turbonilla punicea Dall, 1884 (Figs. 30­31) Turbonilla (viridaria var.) punicea Dall, 1884: 332; Odé (1996: 54). Not Turbonilla punicea: Perry & Schwengel (1955: 120, pl/ 63, fig. 158) (= sp. undet.). Turbonilla (Pyrgiscus) punicea: Powell (1981: 41, fig. 1). Type locality: Cedar Keys, Florida, USA. Type material: Holotype: USNM 35954, Cedar Keys, Florida, USA, Hemphill coll. Additional material examined: USNM 780665, Bogue Sound, North Carolina, USA [2]. Remarks: As shown by Powell (1981), Turbonilla punicea Dall, 1884 (figs. 30­31) can be distinguished by its chubby outline and by the finer striae (fig. 31), which are not so crowded and regularly spaced as in T. puncta.Published as part of Pimenta, Alexandre D. & Absalão, Ricardo S., 2002, On the taxonomy of Turbonilla puncta (C. B. Adams, 1850) (Gastropoda, Pyramidellidae), with the description of a new species from Brazil and remarks on other western atlantic species, pp. 1-16 in Zootaxa 78 on page 11, DOI: 10.5281/zenodo.15593

Turbonilla Risso 1826

Genus Turbonilla Risso, 1826. Type species by subsequent designation (Hermannsen 1852): Turbonilla costulata Risso, 1826. Pliocene, France.Published as part of Pimenta, Alexandre D. & Absalão, Ricardo S., 2002, On the taxonomy of Turbonilla puncta (C. B. Adams, 1850) (Gastropoda, Pyramidellidae), with the description of a new species from Brazil and remarks on other western atlantic species, pp. 1-16 in Zootaxa 78 on page 3, DOI: 10.5281/zenodo.15593

Turbonilla deboeri Jong & Coomans 1988

Turbonilla deboeri Jong & Coomans, 1988 (Figs. 13­17) Turbonilla deboeri Jong & Coomas, 1988: 128, pl. 7, fig. 665; Odé (1996: 39). Type locality: West Indies, Aruba. Type material: Holotype: ZMA 3.87. 106. West Indies, Aruba., K.M. de Jong. coll. Material examined: The types and: ­­Amapá State: MORG 14846, off Goiabal, 103 m, 06/v/ 1968, NOAS coll. [1]; MORG 19920, off Goiabal, 100 m, xi/ 1968, NOAS coll. [2]; MORG 18256, off Amapá State, 76 m, 24 /xi/ 1968, NOAS coll. [1]; ­­Pará State: IBUFRJ 9463, AMASSEDS # 3210 (01° 52.45 ’N, 16.02 ’W, 47 m), 12 /v/ 1990, RVCI coll. [4]; ­­ Pernambuco State: MMUFRPE, Itaparica [27]; IBUFRJ 8835, Bom Despacho, Itaparica, L.Trinchão coll. [1]; ­­Bahia State: MORG 23910, Abrolhos bank, i/ 1985, MORG team coll. [2]; ­­Espírito Santo State: IBUFRJ 8983, off Espírito Santo State [1]; ­­Rio de Janeiro State: IBUFRJ 2540, Prainha, Arraial do Cabo, T.Almeida coll. [5]; IBUFRJ 5974, Prainha, Arraial do Cabo, 1989, T.Almeida coll. [17]; IBUFRJ 7213, Prainha, Arraial do Cabo, 1989, T.Almeida coll. [12]; IBUFRJ 8985, Arquipélago de Santana, Macaé, v/ 1993, AG coll. [5]. Remarks: Turbonilla deboeri (figs. 13­17) has the same spiral sculpture pattern described for T. puncta, but can be distinguished by the outline of the whorls, which are semipyriform, with marked convexity in their posterior halves; and by the larger diameter of the protoconch, which ranges from 256 m to 333 m (mean diameter: 307 m, n = 29; 282 m in the holotype). T. deboeri exhibits some variation in the number of axial ribs per whorl and in the intercoastal spaces.Published as part of Pimenta, Alexandre D. & Absalão, Ricardo S., 2002, On the taxonomy of Turbonilla puncta (C. B. Adams, 1850) (Gastropoda, Pyramidellidae), with the description of a new species from Brazil and remarks on other western atlantic species, pp. 1-16 in Zootaxa 78 on pages 7-8, DOI: 10.5281/zenodo.15593

The genus Brookula Iredale, 1912 (Gastropoda, Trochidae) from Brazil: description of a new species, with notes on other South American species

Absalão, Ricardo S., Miyaji, Cintia, Pimenta, Alexandre D. (2001): The genus Brookula Iredale, 1912 (Gastropoda, Trochidae) from Brazil: description of a new species, with notes on other South American species. Zoosystema 23 (4): 675-687, DOI: http://doi.org/10.5281/zenodo.539390