Taxonomic study on the molluscs collected in Marion-Dufresne expedition (MD 55) to SE Brazil: Xenophoridae, Cypraeoidea, mitriforms and Terebridae (Caenogastropoda) Author Simone, Luiz Ricardo L. Author Cunha, Carlo M. Museu de Zoologia da Universidade de São Paulo, caixa postal 42494, 04218 - 970 São Paulo, SP (Brazil) lrsimone @ usp. br lrlsimone @ gmail. com lrsimone@usp.br text Zoosystema 2012 2012-12-31 34 4 745 781 http://dx.doi.org/10.5252/z2012n4a6 journal article 10.5252/z2012n4a6 1638-9387 5166650 857CAD31-66E1-4CEE-AB4D-CCD64541D0EF Dolichupis akangus n. sp. ( Fig. 4 A-D) TYPE MATERIAL . — Holotype : Brazil , Espírito Santo , off Itaúnas, continental slope of Abrolhos, 18°56’S , 37°52’W , 85-105 m depth, MNHN 25218 ( Fig. 4 A-C) ( MD 55, stn DC 82, Bouchet, Leal & Métivier coll., 28. V .1987 ). Paratypes : same data as holotype , MNHN 25233, 1 shell, MZSP 104028, 2 shells. — Off Regência, 19°40’S , 37°48’W , 790-940 m depth, MNHN 25219, 3 shells, MZSP 104027, 2 shells (stn CB 77, 27. V .1987 ). — Off Itaúnas, 18°59’S , 37°48’W , 607-620 m depth, MNHN 25220, 6 shells, MZSP 104029, 4 shells (stn DC 73, 27. V .1987 ). — Off Conceição da Barra, 18°58’S , 37°49’W , 637 m depth, MNHN 25221, 1 shell ( Fig. 4D ) (stn CB 76, 27. V .1987 ). TYPE LOCALITY . — Brazil , Espírito Santo , off Itaúnas, continental slope of Abrolhos, 18°56’S , 37°52’W , 85- 105 m depth ( MD 55, stn DC 82). DISTRIBUTION. — Off Espírito Santo , Abrolhos continental slope. FIG. 3. — Cypraeoideans: A , Erosaria acicularis ( Gmelin, 1791 ) , MNHN (1), apertural view (L 23.1 mm); B , same, dorsal view; C , Luria cinerea ( Gmelin, 1791 ) , MNHN, stn DC73 (1), apertural view (L 17.0 mm); D , same, dorsal view; E , stn DC75 (1), young specimen, apertural view (L 7.4 mm); F , same, dorsal view; G ; Lamellaria sp. , MNHN (stn DC73), apertural view (L 3.7 mm); H , same, dorsal view; I , Pedicularia tibia Simone, 2005 , MNHN (stn DC73), apertural view (L 3.8 mm); J , same, left view; K , same, right view; L , same, dorsal view; M , Pseudosimnia lacrima n. sp. , holotype MNHN 25217, dorsal view (L 7.5 mm); N , same, right view; O , same, apertural view; P , Cleotrivia antillarum ( Schilder, 1922 ) , MNHN (stn DC73), apertural view (L 4.5 mm); Q , same, right view; R , same, dorsal view; S , same, MZSP 104031, apertural view (L 4.1 mm); T , same, dorsal view. E TYMOLOGY. — The specific epithet is derived from the word “akanga’i” in the Brazilian native Parintintin language, meaning rounded ( Betts 1981 ), an allusion to the rounded fashion of the shell. DIAGNOSIS. — Shell of c. 5 mm , almost spherical; lacking dorsal groove; colour white. Sculpture c. 14 ribs, mostly continuous from side to side; c. 15 ribs in outer lip slightly protruding inside. Aperture in right side (far from central region). DESCRIPTION Shell of c. 5-6 mm ; outline almost spherical, width c. 73% of length, height c. 64% of length. Colour pure white. Anterior and posterior canals similar from each other ( Fig. 4B, C ), slightly protruded, extending less than 10% of shell length. Spire entirely covered; apex not seen. Sculpture c. 14 narrow ribs, mostly perpendicular to longitudinal axis; interspaces about twice ribs width; most ribs running from side to side, entirely lacking dorsal groove; some shells with few ribs, mainly located in both, anterior and posterior regions, ending close to median line; 4-5 ribs, mainly in right side, ending in about half way between ventral region and median line ( Fig. 4A, B, D ); 4-5 ribs located on both canals positioned longitudinally, practically perpendicular to remaining ribs ( Fig. 4A, D ), those closer to median line touching with each other after distance c. 15% of shell length; remaining longitudinal ribs simply ending. Aperture narrow, arched only in both ends; comprising c. 10% of shell width and c. 80% of shell length; located on right third. Outer lip thick, with c. 26% of shell width, anterior and posterior regions extending beyond spire, posterior end more curved than anterior end ( Fig. 4C ); c. 20 transverse ribs, slightly protruding in inner edge, continuing as and similar to dorsal ribs; middle ribs perpendicular to longitudinal shell axis, gradually becoming oblique towards both canals. Siphonal and anal canals narrow, somewhat turned dorsally; siphonal canal more straight and located closer to median line; anal canal weakly more right located, turned to left. Inner lip lacking callus, fossular depression only in anterior half; c. 22 ribs weakly protruded inside aperture. Ribs in ventral region at left from aperture similar and continuous to dorsal ribs. HABITAT. — Sandy-mud bottoms, 85-940 m depth. MEASUREMENTS (in mm). — Holotype : 5.6 × 4.1; paratype MZSP 104028 (1): 5.2 × 3.8; paratype MNHN 25221 : 5.3 × 4.1.