Pseudodiaptomus masoni   Sewell,  1932 (Copepod)
Organism information awaits expert curation
Class: Maxillopoda

Size (female): length 0.943 mm.

The proportional lengths of the cephalothorax and abdomen are as 3 to 2, the abdomen being thus contained 1.5 times in the length of the anterior region of the body.The forehead is prominent and arched. The head and 1st thoracic segment appear to be partially fused together, though the line of demarcation of the two parts can clearly be seen crossing the dorsal aspect. The rostral spines are delicate and are curved downwards and backwards. The posterior thoracic margin is rounded and bears no spines, nor are there any hairs or spinules present.The abdomen consists of four segments, that have with the furcal rami.The genital segment is symmetrical and is but little longer than the following segment; the fourth segment is of considerable length, being nearly half as long again as the 3rd. Segment 2, 3 and 4 are all fringed around their posterior margins with a row of somewhat coarse spines. The furcal rami are nearly one –and-a-half times as long as broad; they are fringed on their inner margin with somewhat sparse hairs.
The 1st antenna reaches back to about the posterior margin of the genital segment of the abdomen, though in some specimens it is little shorter than this, only passing the posterior margin of the thorax by the last segment. It consists of twenty-one free segments.The setae arising from the segments are feebly developed, but that arising from the third last segment is modified and exhibits the same comb-like structure.The 2nd antenna has the usual form, the exopod being nearly twice the length of the endopod.
The mouth-parts are very similar to those of other members of the genus.
In the 1st pair of swimming legs the rami are very nearly equal in length. The 1st segment of the exopod bears a needle-like marginal spine and a single inner seta. Exopod 2 is devoid of a marginal spine; while exopod 3 bears two sub-equal needle-like marginal spines and a stout end-spine.
In the 2nd, 3rd and 4th pairs of legs the 1st segment of the basal region bears scattered needle-like spines on its outer aspect.In the 5th pair of legs there are the usual basal part and three free segments; of these latter the proximal segment appears to be unusually long and is nearly as long as the 2nd free segment. The terminal segment has the usual claw-like shape and the spinous processes are comparatively short.

Synonym (s)

Common Name (s)
Economic Importance and Threats

Habitat:  Estuarine, Coastal


• Andaman and Nicobar Islands, Macpherson Strait (Lat: 11.52) (Long: 92.65) INDIA (Record: 38722)
• West Bengal, Sundarbans (Lat: 21.5) (Long: 88.17) INDIA
• Andaman and Nicobar Islands, Port Blair Harbour INDIA
• Andaman and Nicobar Islands, Macpherson Strait INDIA
• West Bengal, South 24 Parganas INDIA

Literature Source(s)
  • (2002) List of zooplankton found in coastal waters of West Bengal West Bengal Biodiversity Strategy and Action Plan(BSAP), Oct 2002
  • Mandal, AK and Nandi, NC (1989) Fauna of Sundarban mangrove ecosystem, West Bengal, India Fauna of Conservations 3 35431 Available at - NIO, Goa
  • Sewell, RBS (1999) The copepoda of Indian seas Biotech Books, Delhi, India 407 pp Available at - NIO, Goa
  • Society for the Management of European Biodiversity Data (2009) World Register of Marine Species (WoRMS) Available at -
  • Roy, MK (2010) Diversity and Distribution of Crustacea Fauna in wetlands of West Bengal Journal of Environment and Sociobiology Social Environmental and Biological Association, Kolkata, India 7(2) 147-187 Available at - NIO,Goa

Page last updated on:2011-10-27

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