Cadulus parvus Henderson, 1920

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 : 34

Cadulus parvus Henderson, 1920

Figs. 66–69

+ Cadulus amiantus Dall 1889: 431 , in part and omitting figure (fide Henderson 1920); Pilsbry and Sharp 1898: 174, in part and omitting figure (fide Henderson 1920).

+ Cadulus (Platyschides) parvus Henderson 1920: 113 , pl. 18, figs. 2, 4; Scarabino 1985: 202, pl. 73, fig. 1033; 1994: 310, pl. 107, fig. 1521.

+ Cadulus parvus: Absalão 1989: 3 ; Steiner and Kabat 2001: 440; 2004: 627; Absalão et al. 2005: 177, fig. 3.

+ Polyschides parvus: Díaz and Puyana 1994: 258 , pl. 71, fig. 1051.

Type material

Holotype USNM 314713; Paratype MCZ 48414, 1 dd.

Type locality

off Barbados, Blake, 183 m (by original designation).

Diagnosis

Shell to 5 mm long, translucent when fresh. Maximum diameter near center of shell. Ventral side regularly curved, dorsal side with a swell. Apex with four flat lobes, preapical callus conspicuous. Apical and oral sections oval, dorsoventrally depressed.

Material examined

Holotype of Cadulus parvus ; IBUFRJ 9858, sta C61, 1 dd; IBUFRJ 14238, sta A3, 1 dd; MORG 39691, sta D3, 2 dd.

Distribution

USA: Florida; Caribbean Sea: Barbados; off cape San Antonio, Yucatan (Henderson 1920); Colombia (Díaz & Puyana 1994); Brazil: off Cabo Orange, canyon of Amazon river (Scarabino 1985, 1994), Bahia to Rio de Janeiro (Absalão 1989, this study) and off São Paulo (Scarabino 1985, 1994). Shells 79 to 220 m (Henderson 1920; this study), and a one doubtfull record to 1837 m (Henderson 1920).

Remarks

Henderson (1920) described the apex as being composed by some shallow slits and broad, ill­defined lobes. Our material, possess an apex with four slits and four lobes when well preserved ( Fig. 69 ). Díaz and Puyana (1994) also observed this feature and placed this species in the genus Polyschides . Steiner and Kabat (2004) stated that the position of the maximum diameter in the middle of the shell suggests it to belong to Cadulus . However, this feature could be variable, at least theorically, during ontogeny (shell secretion occurs at the aperture and is expected that in some stage of the development the position of maximum diameter could be more close to or at the aperture). Accordingly, we prefer to maintain the original combination but the validity of this allocation in the genus Cadulus should be assessed in the future.

Figures

FIGURES 57 – 73. Genus Episiphon, Entalina, Polyschides and Cadulus. (57) Episiphon didymum, IBUFRJ 14310, 7 mm; (58 – 59) Episiphon sowerbyi, IBUFRJ 14250, 8 mm; (60 – 61) Entalina platamodes, IBUFRJ 13793, 10 mm; (62 – 63) Polyschides portoricensis, IBUFRJ 10576, 7 mm; (64 – 65) Polyschides tetraschistus, (64) Holotype BMNH 1887.2. 9.66, 7 mm, (65) IBUFRJ 14280, 6 mm; (66 – 69) Cadulus parvus, (66) Holotype USNM 314713, 5 mm, (67 – 69) IBUFRJ 9858, 5 mm; (70 – 71) Cadulus eliezeri n. sp., Holotype IBUFRJ 10810, 3 mm; (72 – 73) Cadulus nerta n. sp., Holotype IBUFRJ 14314, 3 mm. Scale bar = 50 m.