Octolasmis grayii   (Darwin),  1851 (Barnacle)
Organism information awaits expert curation
Class: Maxillopoda

Image copyrights: Ocean Science and Technology Cell, CUSAT, Kochi

Size: Capitular length 6 mm; breadth 1.5 mm.

Color: Reddish brown

Capitulum elongated and slightly compressed. Carinal margin irregularly arched; occludent margin sinous; capitular membrane thin and transparent at upper region. Valves 5, narrow and widely separated from each other; size and shape of the capitulum vary much with respect to the age of the specimens.
Carina: Linear, arched and bent at the base, the carina is not forked, basal branch comparatively thin and running parallel to and little distance below basal branch of the scutum; carinal tip usually ending in line with lower tip of the tergal plate. Carina is concave within.
Scutum: With two narrow branches joining very nearly at right angle to each other, one extending along the occludent and the other along the basal margin; occludent branch comparatively broader and longer than basal branch and ends obliquely truncated at the apex; dorsal surface of occludent branch slightly depressed; basal segment very much reduced and less than half as long and narrower than the occludent branch.
Tergum: Axe shaped with a narrow handle; broadens near the base and ends bluntly; valve flat and thin; very widely separated from the carina.
Peduncle: Slightly longer than the capitulum; cylindrical, slender and very soft; membrane smooth and naked.
Cirri: Few basal segments of cirri IV, V and VI conspicuously scaly, which seems to be a characteristic feature.
Caudal appendages: Nearly half as long as the sixth cirri and very slender throughout except the base; tuft of long thin setae at the ends; few in pairs or single along their length.
Mouth parts: Labrum: Bullate with a single row of teeth on the crest.
Mandible: 5 teeth with comparatively narrow space in between; fourth and fifth teeth small and almost equal in size. Sometimes an extra tooth of equal length at the base of the fifth tooth; superior margin with four clusters of fine setae or spinules; inferior margin with a row of closely packed fine setae; body of the mandible, especially near the basal regions of fourth and fifth teeth, with short and sharp spinules of which some project even beyond the narrow clefts.
Inner maxilla: Cutting edge straight, with a deep, broad notch dividing it into upper and lower edge; portion above the notch supports a long and stout spine with a lateral smaller pair below, the edge below the notch bears 6-9 spines of varying size and length; a single, short spine in the middle of the notch; superior margin sinuous , each with 3-4 setae equally spaced; inferior margin slightly sinuous with cluster of spinules of equal length; body surface with transverse rows of fine spinules.

Synonym (s)
Dichelaspis grayii Darwin 1851
Dichelaspis pellucida Annandale 1909
Dichelaspis pellucida Darwin 1851
Octolasmis grayii Nilsson-Cantell 1938a

Common Name (s)
Economic Importance and Threats



• Orissa INDIA
• Tamil Nadu, Chennai (Lat: 13.09) (Long: 80.29) INDIA
• Tamil Nadu, Parangipettai INDIA (Record: 1970)
• Orissa, Puri beach INDIA (Record: 2006)
• Tamil Nadu, Off Chennai INDIA (Record: 2006)
• Tamil Nadu, Nagapattinam INDIA (Record: 2006)
• Tamil Nadu, Gulf of Mannar INDIA (Record: 2003)

Literature Source(s)
  • Mohan RSL; Dey, SC and Bairagi, SP (1998) On a resident population of the Ganges river dolphin, Platanista gangetica Journal of the Bombay Natural History Society 95(1) 39820
  • Fernando, SA (2006) Monograph on Indian Barnacles Ocean science and technology Cell, Kochi 9-199 Available at - NIO, Goa
  • Society for the Management of European Biodiversity Data (2009) World Register of Marine Species (WoRMS) Available at - http://www.marinespecies.org
  • Marine Biological Station, Chennai, Tamil Nadu (2003) Checklist of marine fauna of Tamil Nadu Department of Environment, Government of Tamil Nadu Available at - http://tnenvis.nic.in
  • Dr. Ramesh, R; Dr. Nammalwar, P and Dr. Gowri, VS (2008) Database on coastal information of Tamil Nadu Report Submitted to Environmental Information System (ENVIS) Centre, Department of Environment, Government of Tamil Nadu Institute for Ocean Management, Anna University, Chennai, Tamil Nadu. Available at - http://tnenvis.nic.in/PDF/coastal%20data.pdf

Page last updated on:2012-05-21

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