Gadila pocula (Dall, 1889)

Caetano, Carlos Henrique Soares, Scarabino, Victor & Absalão, Ricardo Silva, 2006, Scaphopoda (Mollusca) from the Brazilian continental shelf and upper slope (13 º to 21 ºS) with descriptions of two new species of the genus Cadulus Philippi, 1844, Zootaxa 1267, pp. 1-47 : 41-42

Gadila pocula (Dall, 1889) n.comb

Figs. 84–85

+ Cadulus poculum Dall 1889: 429 ; Abbott 1974: 390.

+ Cadulus (Gadila) poculum: Pilsbry and Sharp 1898: 172 , pl. 33, figs. 56, 57. + Cadulus (Platyschides) poculum: Henderson 1920: 108 , pl. 17, fig. 8. + Polyschides poculum: Steiner and Kabat 2001: 448 ; 2004: 631.

Type material

Lectotype USNM 95374 (designated by Henderson, 1920: 109); Paralectotypes USNM 887461, 1 dd, MCZ 7743, 1 dd.

Type locality

off st. Vincent, West Indies, Blake sta 226, 13 º09’05"N, 61º16’20"W, 774 m (by subsequent designation).

Diagnosis

Shell medium size (to 11mm), slender, strongly curved posteriorly, solid, brilliant. E quator located at first forth, more notorious at ventral side where it is obtuse angled. Apex simple or with two flat lateral lobes, denticle­like structure at ventral edge. Pre­apical callous thick, lumen oval. Apical section dorsoventrally depressed; oral aperture oblique, strongly dorsoventrally depressed.

Material examined

IBUFRJ 14312, off Bacia de Campos, Rio de Janeiro, 22º26’28"S, 39º58’53"W, 1050 m, 1 dd.

Distribution

off St. Vincent (Dall 1889); off Yucatan bank (Henderson 1920); Brazil: Rio de Janeiro (this study). Shells 774 to 1173 m (Henderson 1920; this study).

Remarks

Steiner and Kabat (2001, 2004) placed this species at the genus Polyschides because of the position of the maximum diameter at anterior third of the shell, occurrence of apical lateral projections that, according to these authors, indicate four apical lobes, and the strongly oblique anterior aperture. Acccording to Steiner and Kabat (2004) this species could also be placed in Gadila . The specimen studied is well preserved and the carefull examination of the apical features shows only two lateral flat lobes and none ventral or dorsal projections. In this manner, we concluded that the studied species fits better to the concept of genus Gadila than Polyschides .

Figures

FIGURES 74 – 89. Genus Gadila and Compressidens. (74 – 77) Gadila dominguensis, (74) Syntype BMNH 1854.10. 4.466, 7 mm, (75 – 76) IBUFRJ 9513, 8 mm; (77) Gadila acus, Lectotype USNM 95379, 8 mm; (78 – 80) Gadila pandionis, (78) Lectotype USNM 38644, 10 mm, (79 – 80) IBUFRJ 14314, 13 mm; (81 – 83) Gadila simpsoni, (81) Holotype USNM 161580, 7 mm, (82 – 83) IBUFRJ 14317, 5 mm; (84 – 85) Gadila pocula, IBUFRJ 14312, 10 mm; (86 – 89) Compressidens pressum, IBUFRJ 10966, 9 mm. Scale bar = 500 m.