Gadila pandionis

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 : 39-40

Gadila pandionis (Verril & Smith in Verril, 1880)

Figs. 78–80

+ Cadulus pandionis Verril and Smith (in Verril) 1880: 392, 399; Verril 1882: 558, pl. 58, figs. 30, 30a.

+ Cadulus (Gadila) pandionis: Pilsbry and Sharp 1898: 171 , pl. 25, fig. 63. + Gadila pandionis: Steiner and Kabat 2001: 445 ; 2004: 626.

Type material

Lectotype USNM 38644 (designated by Johnson, 1989: 56 as " Holotype "); Paralectotypes MCZ 186811, 3 dd, MCZ 186812, 1 dd, MCZ 186813, 2 dd, MCZ 186814, 7 dd.

Type locality

off Martha’s Vineyard, Massachusetts, USBF sta 876, 219 m (by subsequent designation).

Diagnosis

Shell medium (to 13 mm), white, slender, strongly curved, mainly in the posterior third. Maximum diameter at anterior third. Ventral side well curved; dorsal side curved except for occurrence of bulge at maximum diameter. Dorsal view fusiform, fast tapering from the maximum diameter to apex. Apex oval, lateral view rounded. Apex with two Ushaped notches, one ventral and other dorsal. Preapical callus thin, lumen suboval. Oral aperture oblique, sligthtly dorsoventrally depressed.

Material examined

Lectotype of Gadila pandionis ; IBUFRJ 10698, sta C13, 13 dd; IBUFRJ 10917, sta C35, 2 dd; IBUFRJ 14313, sta R4#1, 5 dd; IBUFRJ 14314, Jops II, sta 3201, 21 º37’S, 39º54’W, 1320 m, 3 dd.

Distribution

USA: New Jersey to Florida (Henderson 1920, Steiner & Kabat 2004); Brazil: Bahia, Espírito Santo, Rio de Janeiro (this study). Shells 46 to 1320m (Henderson 1920, this study).

Remarks

As pointed out by G. perlonga , we consider that Johnson’s lectotype designation (Johnson, 1989: 56) as valid because in spite of wrong use of the term holotype, the author explicitly selected from the type series a particular specimen to serve as the name­bearing type (see ICZN Art. 74.5).

Gadila pandionis resembles most closely G. watsoni (Dall, 1881) sharing apical features, two semicircular notches, one dorsal and one ventral, leaving two lateral pointed lobes ( Fig. 80 ). The distinction between these two species is questionable; the lectotype of G. w a t s o n i is a broken shell and the paralectotype is a juvenile that makes any comparisons difficult.

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.