Katelysia opima   (Gmelin,  1791) (Clam)
Organism information awaits expert curation
Class: Bivalvia

Color: Pale yellowish brown or straw colored

The shell is thick, solid and inflated with a smooth and glossy surface. The inner surface of the valves is white and the pallial line deeply sinuate. The shell is slightly longer than high, with an evenly rounded margin. The hinge bears three strong cardinal teeth, the tooth in front of the cardinals in the left valve and the hollow in the right being absent. The lunule is distinct, flattened and rather broad. The area behind the umbones is also well defined, flattened and greatly elongated, reaching almost up to the hind margin of the shell. The muscular impressions are very well marked and even slightly depressed, that of the anterior adductor being more strongly so. The pallial line is deeply sinuate. The inner surface is smooth, white and polished and devoid of any trace of denticulation. The outer surface is also highly polished and is pale yellowish brown or straw colored, variously clouded, mottled and rayed with purplish gray markings. The pattern most frequently observed is a number of concentric, undulating lines, running closely parallel, with three or four broad, radially widening, brownish or purplish gray bands diverging downwards from the umbo. The umbo is more pronounced in young specimens.

Synonym (s)

Common Name (s)
• Vazhukku Matti (Tamil)
Economic Importance and Threats

Habitat:  Estuarine, Muddy, Coastal


• Maharashtra, Malvan (Lat: 16.07) (Long: 73.47) INDIA
• Goa, Terekhol Estuary (Lat: 15.72) (Long: 73.7) INDIA
• Goa, Terekhol Estuary (Lat: 15.72) (Long: 73.7) INDIA
• Tamil Nadu, Parangipettai Coast (Lat: 11.48) (Long: 79.77) INDIA
• Maharashtra, Kalbadevi Estuary INDIA
• Maharashtra INDIA
• Maharashtra, Tarkarli Creek INDIA
• Tamil Nadu, Adyar Estuary INDIA
• Andhra Pradesh, Kakinada Bay INDIA
• Maharashtra, Mahim Bay INDIA
• Tamil Nadu, Pamban INDIA
• Maharashtra, Ratnagiri Coast INDIA
• Maharashtra, Mumbai INDIA
• Karnataka, North Kanara INDIA
• Kerala, Kochi Coast INDIA
• Tamil Nadu, Mandapam INDIA
• Maharashtra, Ratnagiri INDIA

Literature Source(s)
  • Zoological Survey of India (Eds) (1991) Animal resources of India (Protozoa to Mammalia) ZSI 1-694 Available at - NCL, Pune
  • Shanmugam, A; Rajagopal, S and Nazeer, RA Common bivalves of Parangipettai coast Available at - NIO, Goa
  • Balasubramanian, T Lagoons of India Environmental Information System Centre, Envis Publication Series: 3/2001 105 pp Available at - http://aucasmbenvis.org/files/04-Publications/lagoon%20status.pdf
  • Dhargalkar, V and Ingole, B (2005) Survey of inventorization of coastal biodiversity at three estuarine sites along the central west coast of India 1 Available at - NCL, Pune
  • Mane, UH and Nagabhushanam, R (1987) Reproduction in edible bivalve shellfishes of Ratnagiri coast National seminar on shellfish resources and farming CMFRI 167-176 Available at - eprints.cmfri.org.in/2566/1/Article_41.pdf
  • Alagarswami, K and Narasimham, KA (1973) Clam, cockle and oyster resources of the indian coasts Living resources of the seas around India CMFRI, Cochin 648-658 Available at - http://eprints.cmfri.org.in/2760/1/Article_49.pdf
  • Nayar, KN and Mahadevan, S (1974) Edible Bivalves; Clams and others The commercial molluscs of India Bulletin Of Central Marine Fisheries Research Institute CMFRI, Cochin 25 40-53 Available at - http://eprints.cmfri.org.in/643/1/Nagappan_and_Mahadeven1.pdf
  • Sundaram, KS; Sarvesan, R; Mohamed, KH and Shanbhogue, SL (1969) Catalogue of molluscs, prawns, stomatopods and marine algae in the reference collections of the central marine fisheries research institute Bulletin Of Central Marine Fisheries Research Institute CMFRI, Cochin 9 1-52 Available at - http://eprints.cmfri.org.in/570/1/Bulletin_9.pdf
  • Jones, S (1969) The molluscan fishery resources of India Proceedings of the Symposium on Mollusca CMFRI 906-918 Available at - http://eprints.cmfri.org.in/2371/1/Article_26.pdf
  • Pillai, PKM and Augustine, SK (2000) A code list of common marine living resources of the Indian seas CMFRI Special Publication No.12 CMFRI 1-115 Available at - eprints.cmfri.org.in/3975/1/Special_Publication_No_12_Revised.pdf

Page last updated on:2011-12-19

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