Asaphis violascens   (Forskal,  1775) (Clam)
Organism information awaits expert curation
Class: Bivalvia

Image copyrights: Guido T. Poppe & Philippe Poppe

Size: Maximum shell length 11 cm, commonly to 6.5 cm.

Color: Outside of shell dull colored, usually creamy white with a pale grayish brown periostracum, not uncommonly suffused with purple, pink, or orange, at least on the umbones, sometimes with poorly distinct radial bands of purplish brown. Interior slightly glossy, whitish, often with yellow or orange hue centrally and a dark purplish blotch posteriorly. Purplish coloration mostly developed on ligamental nymphs and posterior margin, sometimes extending to the whole inner surface of valves.

Shell solid, rather large, inflated, slightly gaping posteriorly, elongate-ovate in outline but quite variable in shape and sculpture. Umbones a little forward of mid-length of shell. Posterior margin convex, somewhat obliquely truncate, meeting the straight posterodorsal margin at an obtuse angle. Anterodorsal margin sloping toward the rounded anterior margin. Ventral margin broadly arched, often less strongly so posteriorly. Outer sculpture of numerous, strong, rounded and often forked radial ribs, developed throughout the valves and crossed by concentric lines that do not interrupt the ribs but make them slightly scaly or nodulose, at least on posterior slope. Periostracum thin, easily worn off. Hinge with 2 cardinal teeth in each valve, the anterior tooth of left valve and posterior tooth of right valve larger, bifid and strongly protruding. Pallial sinus relatively shallow, not reaching level with umbones anteriorly. Ventral limb of pallial sinus sloping obliquely, meeting pallial line a short distance before its posteroventral end.

Synonym (s)
Asaphis dichotoma (Anton, 1838)
Asaphis deflorata (Linnaeus, 1758)
Asaphis deflorata Hornell, 1921
Asiphis violascens Cernohorsky, 1972

Common Name (s)
• Violet Asphis (English)
Economic Importance and Threats
Importance:  Commercial
(Collected for food and locally marketed. The shell is used to make decorative items and toys.)

Habitat:  Sandy


• Andaman and Nicobar Islands INDIA
• Lakshadweep INDIA

Literature Source(s)
  • (2002) Lakshadweep Islands biodiversity strategy and action plan (Version: 3)
  • Tikadar, BK; Daniel, A and Subbarao, NV (1986) Sea shore animals of Andaman and Nicobar Islands The Director, ZSI, Kolkatta 188 Available at - ZSI, Pune
  • Subba Rao, NV and Dey, A (2000) Catalogue of marine molluscs of Andaman and Nicobar Islands Occasional paper no 187 Records of the Zoological Survey of India ZSI 1-323 Available at - NCL, Pune
  • Oliver, PG; Holmes, AM; Killeen, lJ and Wood, H (2004) Annotated checklist of the marine Bivalvia of Rodrigues Journal of Natural History Taylor and Francis 38 3229-3272 Available at -
  • Tan, KS and Kastoro, WW (2004) A small collection of gastropods and bivalves from the Anambas and Natuna Islands, south China Sea The Raffles Bulletin of Zoology 11 47-54
  • Juntongjin, K; Piyakarnchana, T; Kodama, M; Kogure, K; Simidu, U and Ohwada, K (1996) Marine bacteria that produce toxins similar to paralytic shellfish poisons and tetrodotoxins from the sand clam (Asaphis violascens) of the Gulf of Thailand Journal of Marine Biotechnology 3(4) 268-273 Available at - Zoological Records
  • Society for the Management of European Biodiversity Data (2009) World Register of Marine Species (WoRMS) Available at -
  • Poutiers, JM (1998) Bivalves FAO species identification guide for fishery purposes. The living marine resources of the western central Pacific. Volume 1: Seaweeds, corals, bivalves and gastropods FAO, Rome 1 686 pp Available at -
  • Surya Rao, KV and Subba Rao, NV (1991) Mollusca State fauna series 2: Fauna of Lakshadweep ZSI, Calcutta 273-362 Available at - NIO, Goa
  • Poppe, GT and Poppe, P (1996) Conchology, Inc. Conchology, Inc. Available at -

Page last updated on:2010-05-20

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