Antalis circumcincta (Watson, 1879)

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 : 15-16

Antalis circumcincta (Watson, 1879)

Figs. 23–28

+ Dentalium circumcinctum Watson 1879: 513 ; 1886: 7, pl. 1, fig. 7.

+ Dentalium (Antalis) circumcinctum : Pilsbry and Sharp 1897: 88, pl. 8, fig. 26; Henderson 1920: 68, pl. 11, fig. 7.

+ Dentalium (Graptacme) circumcinctum : Lange de Morretes 1949: 54; Abbott 1974: 386.

+ Antalis circumcinctum : Scarabino 1985: 198, pl. 72, fig. 1011; 1994: 306, pl. 106, fig. 1499; Sumida and Pires­Vanin 1997: 781.

+ Antalis circumcincta : Steiner and Kabat 2001: 440; 2004: 576.

Type material

Lectotype (here selected, see remarks) BMNH 1887.2.9.30; Paralectotypes BMNH 1887.2.9.26, 2 dd, BMNH 1887.2.9.29, 1 dd, BMNH 1887.2.9.24­25, 2 dd.

Type locality

off Recife, Pernambuco, Brazil (here restricted), Challenger sta 122, 09 °05’S, 34°50’W, 639 m.

Diagnosis

Shell to 50 mm long, slightly curved, slender, white. Low primary ribs (15­20), crossed by transversal lines giving an irregular aspect to the whole surface. Apex simple or V­ or U­shaped notch on convex side. Apical, oral sections subcircular.

Material examined

Lectotype and Paralectotypes of A. circumcincta ; IBUFRJ 8083, sta 517, 15 dd; IBUFRJ 10912, sta C21f, 1 dd; IBUFRJ 10925, sta C35, 19 dd; IBUFRJ 14301; sta 41, 6 dd; IBUFRJ 14302, sta A3, 6 dd; IBUFRJ 14303, sta R2#3, 1 dd; IBUFRJ 14304, sta 509, 1 dd; IBUFRJ 14305, sta 538, 1 dd.

Distribution

Caribbean Sea: off Bermuda (Watson 1886, Abbott 1974); West Indies: St. Thomas (Watson 1879); Brazil: off Pernambuco, Recife (Watson 1879), Bahia to Rio de Janeiro (this study) and São Paulo (Sumida & Pires­Vanin 1997). Empty shells 247 to 1000 m (this study).

Remarks

Watson (1879) described this species from material collected in the West Indies, Northern Brazil and from Setubal, off Portugal (Challenger sta 2, 38 °10.8’N, 09°14’W). This last lot, BMNH 1887.2.9.24­25, consists of two specimens here considered as belonging to a different species. So, with the express taxonomic purpose of taxon stabilization (ICZN, Art. 74.7.3), we are selecting the larger specimens gathered off Pernambuco (BMNH 1887.2.9.30) as the lectotype ( Fig. 23 ). We choose this specimen because it agrees perfectly with the concept of Antalis circumcincta and was the specimen figured at Watson (1886: pl. 1, fig. 7). Watson (1886: 7) subsequently recorded two specimens from off Bermuda, which are in the type collection, BMNH 1887.2.9.27­28, but Steiner and Kabat (2004) stated that these specimens are not types.

Antalis obscurum (Dall, 1889) , reported from the Lesser Antilles to Brazil (Steiner & Kabat 2004), seems to be a junior synonym of A. circumcincta , but the assessment of this species is beyond the scope of this contribution. The high number of ribs and polygonal apical section distinguishes A. circumcincta from the other species of the genus.

Figures

FIGURES 20 – 38. Genus Antalis and Coccodentalium. (20 – 22) Antalis cerata, IBUFRJ 14253, 27 mm; (23 – 28) Antalis circumcincta, (23) Lectotype BMNH 1887.2. 9.30, 48 mm, (24) Paralectotype BMNH 1887.2. 9.29, 46 mm, (25 – 28) IBUFRJ 14302, 48 mm; (29 – 32) Antalis taphria, IBUFRJ 14254, 16 mm; (33 – 38) Coccodentalium carduus, IBUFRJ 14245, 89 mm. Scale bar = 100 m.