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 Mitromorpha sama n. sp. ( Fig. 9 A-F) TYPE MATERIAL . — Holotype : Brazil , Espírito Santo , off Itaúnas, continental slope of Abrolhos, 19°00, 37°48’W , 607-620 m depth, MNHN 25224 ( Fig. 9A, B ) ( MD 55, stn DC 73, Bouchet, Leal & Métivier coll., 27. V .1987 ). Paratypes : same data as holotype , MNHN 25225, 6 shells, MZSP 102973, 2 shells ( Fig. 9 C-F). — Off Regência, 19°40’S , 37°48’W , 790-940 m depth, MNHN 25226, 1 shell (stn CB 77). TYPE LOCALITY . — Brazil , Espírito Santo , off Itaúnas, continental slope of Abrolhos, 19°00, 37°48’W , 607-620 m depth ( MD 55, stn DC 73). DISTRIBUTION. — Off Espírito Santo , Abrolhos continental slope. ETYMOLOGY. — The specific epithet is derived from the Tupi-Guarani word “sama”, meaning cord, line; an allusion to the aligned fashion of the axial sculpture. DIAGNOSIS. — Shell length c. 7 mm , biconic; protoconch paucispiral; sculpture delicate reticulate, with axial cords somewhat aligned along whorls.Aperture elongated; outer lip lyrate within, preceded by slope and axial thread; inner lip with pair of columellar folds. DESCRIPTION Shell: length up to 6.6 mm , outline biconic ( Fig. 9 A-D); width c. ½ length. Colour uniform pale beige. Protoconch whitish, of 1.5 whorls, mammillate ( Fig. 9E ); comprising c. 5% of length and c. 18% of shell width; surface smooth, glossy; transition with teleoconch clear, orthocline. Spire conic, comprising c. ½ of shell length; spire angle c. 55°. Teleoconch of about five whorls, profile straight, suture plane. Sculptured by series of pustules, aligned both axially and spirally, forming uniform reticulation; c. 20 axial and four spiral lines of pustules in penultimate whorl ( Fig. 9B, D ); c. 20 spiral lines in initial region of body whorl ( Fig. 9A, C ); axial lines somewhat continuous with neighbour whorls; subsutural line slightly larger in c. ½ of specimens. Differentiable slope, preceded by axial, low thread, located c. ∕₅ whorl preceding outer lip ( Fig. 9D ); outer lip thicker on thread, becoming thinner towards edge, with outer surface weakly sculptured. Aperture elliptic, c. ½ of shell length and c. ¼ shell width ( Fig. 9A, D ); c. 3 times longer than wide; weakly oblique related to longitudinal shell axis. Outer lip internally lyrate, with 4-5 spiral inner, weak cords, being upper cord larger, becoming gradually narrower in peri-siphonal region ( Fig. 9C ). Inner lip slightly concave, possessing pair of low, middle folds, being uppermost fold slightly larger than inferior fold ( Fig. 9F ). Siphonal canal short, slightly rostrate, projected forwards and dorsally ( Fig. 9D ). No broad callus or umbilicus. MEASUREMENTS (inmm). — Holotype : 6.6 × 3.2; paratype MZSP 102973 (1): 5.6 × 2.6. HABITAT. — Sandy-mud bottoms, 607-940 m depth.