Alexandre Dias Pimenta

Novas ocorrências de gastrópodes e bivalves marinhos no Brasil (Mollusca)

The gastropods Costaclis egregia (Dall, 1889), Thaleia nisonis (Dall, 1889), Tjaernoeia michaeli Engl, 2001 and the bivalves Bathyarca sp., Myonera aff. ruginosa (Jeffreys, 1882) are recorded for the first time in Brazilian waters. This paper presents a brief description of these species and also include ilustrations.

Taxonomic review of the family Discodorididae (Mollusca: Gastropoda: Nudibranchia) from Brazil, with descriptions of two new species

The family Discodorididae was previously represented by 11 species in Brazil; however, recently collected specimens from several localities in Rio de Janeiro, in addition to the study of material previously deposited in scientific collections, revealed the existence of 13 taxa: Diaulula greeleyi (MacFarland, 1909), Discodoris hummelincki (Ev. Marcus & Er. Marcus, 1963) comb. nov., Discodoris branneri MacFarland, 1909, Geitodoris pusae (Er. Marcus, 1955), Hoplodoris hansrosaorum Domínguez, García & Troncoso, 2006, Jorunna spazzola Er. Marcus, 1955, Jorunna spongiosa sp. nov., Paradoris mulciber (Ev. Marcus, 1971), Platydoris angustipes (Mörch, 1863), Rostanga byga Er. Marcus, 1958a, Taringa telopia Er. Marcus, 1955, Taringa iemanja sp. nov., and Thordisa diuda Er. Marcus, 1955. Discodoris voniheringi MacFarland, 1909 was previously regarded as nomen dubium, and this view is maintained in the present study. Three new records for the Brazilian coast are recognized among these 13 taxa; the previous record of Diaulula phoca (Ev. Marcus & Er. Marcus, 1967a) is rectified as Discodoris hummelincki comb. nov., constituting the first record of this species from Brazil; two new species, Taringa iemanja sp. nov. and Jorunna spongiosa sp. nov., are described in anatomical detail. The following taxa, which were formerly considered junior synonyms of species studied in this work, have been revalidated: Diaulula nayarita (Ortea & Llera, 1981), from the Pacific coast of Costa Rica, which differs from Diaulula greeleyi in the length and width of caryophyllidia; Discodoris mortenseni Ev. Marcus & Er. Marcus, 1963, from the Caribbean, which is likely to belong to Jorunna, yet differs from Jorunna spazzola in body size and coloration, radula appearance, and number of lamellae in the rhinophores; Jorunna luisae Ev. Marcus, 1976, which differs from Jorunna spazzola in the reproductive system, mainly in the size and shape of the accessory gland; and Thordisa azmani Cervera & García-Gómez, 1989, which differs from Thordisa diuda in the presence of two accessory glands in the genital atrium and the absence of one denticle in the external surface of the inner lateral teeth. Finally, the specimens of Geitodoris pusae reported from the European coast and Mediterranean Sea show differences in general coloration and in the radula, gill, and reproductive system, thereby these specimens likely refer to different taxa.

First record of the genus Onchidoris (Gastropoda: Nudibranchia: Onchidorididae) from the South Atlantic Ocean, with the description of a new species from Brazil

A new species of the genus Onchidoris is described from the south-western Atlantic, on the coast of Brazil, in the States of Rio de Janeiro and Sao Paulo. To date, the genus Onchidoris is known almost exclusively from the northern hemisphere, especially the Atlantic coast of Europe and the Mediterranean Sea. The single previous record from the southern hemisphere is Onchidoris maugeansis , described from Australia. This is the first record of the family Onchidorididae from the coast of Brazil. Onchidoris brasiliensis sp. nov. is very similar to Onchidoris depressa , from England and the northern coast of Spain, but is distinguished by the presence of a triangular protuberance on the edge of the inner lateral radular tooth and a wide closed branchial circle with tubercles inside. Furthermore, the egg mass of O. brasiliensis sp. nov. contains a single row of eggs, whereas that of O. depressa has multiple rows. Onchidoris brasiliensis sp. nov. has lecithotrophic development, the first record of this type of development in the genus. There is a relationship between O. brasiliensis sp. nov. and the bryozoan Parasmittina protecta.

Taxonomic review of the genus Opaliopsis (Gastropoda: Nystiellidae) from Brazil, with description of a new species

The genus Opaliopsis from Brazil is revised based on three deep-water species. Opaliopsis atlantis (Clench & Turner, 1952) is confirmed as occurring in north-eastern and south-eastern localities. Opaliopsis opalina (Dall, 1927) is reported for the first time in the south-western Atlantic. A new species, Opaliopsis cearense, is described from the north-eastern Brazilian coast, and is distinguished by its large number of fine spiral cords per teleoconch whorl.

Mollusca, Bivalvia, Mytilidae, Myoforceps aristatus (Dillwyn, 1817): distribution and new record localities at Ilha Grande Bay, Brazil

In many intertidal rocky shores at Ilha Grande Bay, state of Rio de Janeiro, Brazil, the vermetid gastropod Petaloconchus varians is the dominant organism, forming a well-developed and complex structure, where different groups of organisms live, including the invasive bivalve Myoforceps aristatus . The present paper describes the distribution and new record localities of M. aristatus at Ilha Grande Bay.

A Taxonomic Review Of The Genera Boonea, Chrysallida, Parthenina, Ivara, Fargoa, Mumiola, Odostomella And Trabecula (Gastropoda, Pyramidellidae, Odostomiinae) From Brazil

Pimenta, Alexandre Dias, Absalao, Ricardo Silva, Miyaji, Cintia (2009): A taxonomic review of the genera Boonea, Chrysallida, Parthenina, Ivara, Fargoa, Mumiola, Odostomella and Trabecula (Gastropoda, Pyramidellidae, Odostomiinae) from Brazil. Zootaxa 2049: 39-66, DOI: 10.5281/zenodo.186507

New species and records of Newtoniellinae (Caenogastropoda, Newtoniellidae) from Brazil

Newtoniellinae is a worldwide marine group of cold-water, deep-sea species, comprising the genera Cerithiella, Paramendax and Trituba . Prior to this study, the subfamily was represented in Brazil by four species of Cerithiella . The present contribution adds new Brazilian records of two of these species, Cerithiella amblytera and Cerithiella enode , in addition to new records of two species previously known only from Cuba and the south-eastern USA, respectively: Cerithiella sigsbeana comb. nov. and Cerithiella producta . Two new species of Cerithiella from Brazil are described: Cerithiella atali sp. nov. has a pointed protoconch identical to the species described in the previously synonymized genus Stilus; Cerithiella candela sp. nov. has the teleoconch very similar to Cerithiella pernambucoensis , but is differentiated by the protoconch morphology. Also, a new species of Trituba is described, Trituba anubis sp. nov., which is the second species of this genus recorded for the western Atlantic. Eumetula axicostulata comb. nov. and Eumetula vitrea comb. nov., both from the western Atlantic but not recorded from Brazil, are transferred from the genus Cerithiella . This study increases from four to nine the number of known species of Newtoniellinae from Brazil.

Comparative Morphology of Leucozonia from Brazil (Neogastropoda: Buccinoidea: Fasciolariidae)

Abstract: The morphology of the fasciolariid gastropods Leucozonia nassa (Gmelin, 1791), L. ocellata (Gmelin, 1791) and L. ponderosa Vermeij and Snyder, 1998 from Brazil is described. Examination of several shells from the oceanic island of Trindade, off southeastern Brazil confirmed the conchological differences between L. ponderosa and L. nassa. In addition, the first occurrence of L. ponderosa is documented from the Fernando de Noronha Archipelago, off northeastern Brazil. The anatomy of L. ponderosa is shown to be identical to L. nassa, except for minor radular features; however, the male genital system was not examined because of the lack of male specimens of L. ponderosa available for study. Leucozonia ocellata differs from L. nassa and L. ponderosa in having a proportionally smaller seminal receptacle and bursa copulatrix, a rhynchostome with lip-like margins, a curved anterior esophagus, and a cement gland with a posteriorly folded branch. Anatomic characters of the species studied here agree with the previous descriptions of fasciolariid anatomy.

Taxonomic review of Metaxia (Gastropoda: Triphoridae) from Brazil, with description of a new species

The taxonomy of the species of Metaxia Monterosato, 1884 from Brazil is revised. Previously to this study, only Metaxia excelsa Faber & Moolenbeek, 1991 was known to occur in this country, under its older name Metaxia exilis (C.B. Adams, 1850). The review of a large amount of shells in malacological collections in Brazil revealed the occurrence of three known additional species: Metaxia taeniolata (Dall, 1889); Metaxia rugulosa (C.B. Adams, 1850); Metaxia prompta Rolan & Fernandez-Garces, 2008, all previously reported from the southeast coast of the USA and/or the Caribbean region. Metaxia gongyloskymnus sp. nov., diagnosed by the globose protoconch with continuous axial ribs and microscopic spiral sculpture, is restricted to localities off the Southeastern Brazilian coast.

Four new species and two new records of Odostomiinae (Gastropoda: Pyramidellidae) from Brazil

Four new species of the pyramidellid Odostomiinae from Brazil are described: Chrysallida conifera sp. nov., characterized by a small and regularly conical shell with prominent nodules; Parthenina biumbilicata sp. nov., characterized by a deep and wide umbilicus and a regularly increasing aperture diameter at the protoconch, which bears a small circular umbilicus; Eulimastoma franklini sp. nov., which is very similar to Eulimastoma dydima (Verrill & Bush, 1900) but has a prominent helicoid protoconch; Eulimastoma exiguum sp. nov., similar to Eulimastoma weberi (Morrison, 1965) but without spiral ridges. Fargoa diantophila (Wells & Wells, 1961) and Chrysallida nioba (Dall & Bartsch, 1911) are reported from the southwestern Atlantic for the first time.