Protapes gallus (Gmelin, 1791)

Arathi, Anitha R., Oliver, P. Graham, Ravinesh, Raveendhiran & Kumar, Appukuttannair Biju, 2018, The Ashtamudi Lake short-neck clam: re-assigned to the genus Marcia H. Adams & A. Adams, 1857 (Bivalvia, Veneridae), ZooKeys 799, pp. 1-20 : 10-11

Protapes gallus (Gmelin, 1791) Figure 10

Original combination.

Venus gallus Gmelin, 1791

Synonyms.

(from MolluscaBase 2018a) Venus malabarica Dillwyn, 1817; Venus rhombifera Bory de Saint-Vincent, 1827; Tapes lentiginosa Reeve, 1864.

Type locality.

As the name Venus malabarica Chemnitz, 1782 is unavailable this species takes the name of Venus gallus Gmelin, 1791, both names referring to Chemnitz, 1782 tab. 31, figs 324-325. The type locality is given as the Malabar coast by Chemnitz (1782), which largely equates with the coast of modern Kerala.

Material examined.

Neendakara, Kollam, 5 live collected specimens + 10 empty articulated shells; Dharmadam, Kannur, 6 live collected specimens + 4 empty articulated shells.

Description.

Shell to 60 mm in length, solid, compressed, inequilateral, beaks slightly to the anterior. Outline trigonal-subovate, lunule margin impressed, anterior margin pronounced, posterior ventral margin weakly truncated, posterior dorsal margin sloping steeply. Lunule lanceolate, demarcated by shallow groove. Escutcheon long, narrow, weakly striated. Sculpture of evenly sized, rounded, closely spaced, commarginal ribs separated by narrow grooves. Pallial sinus wide, deep, ascending steeply toward umbonal cavity. External colouration light brown with narrow and light zigzag or chevron streaks with four distinct brown rays radiating from the beak to the ventral margin. Shell interior white with yellowish tinge on the umbonal cavity.

Distribution.

Protapes gallus has an Indo-West Pacific distribution extending from India to China ( Huber 2010) but Chen et al. (2014) suggests that cryptic species may also be present.

Remarks.

This species was described as Venus malabarica by Chemnitz (1782, figs. 324, 325) with the type locality of the Malabar coast in southwest India. Using Chemnitz’s (1782) figures, Gmelin (1791) erected the name Venus gallus and repeated the type locality of the Malabar coast. No type material could be located in Copenhagen or St Petersburg collections, consequently all nomenclature is based on the figures in Chemnitz. These figures are sufficient to place this taxon in the genus Protapes and this taxon was adopted as the type of the genus by Dall (1902). Although Chemnitz’s name is invalid for nomenclatural purposes, it was still being used in the late twentieth century by Fischer-Piette and Metivier (1971).