Valdiviella insignis   Farran,  1908 (Copepod)
Organism information awaits expert curation
Taxonomy
Kingdom:Animalia
Phylum:Arthropoda
Class: Maxillopoda
Order:Calanoida
Family:Aetideidae

Description
Size (male): length 8.7 mm

The proportional lengths of the cephalothorax and abdomen are as 33 10 12, so that the abdomen is contained 2.75 times in the length of the anterior region of the body.The head and 1st thoracic segment are fused and thoracic segments 4 and 5 are partially fused. The posterior margin is rounded and is armed with a short backwardly directed spine.
The abdomen consists of five segments. Segments 2, 3 and 4 are armed across the dorsal aspect with a row of small spines on the posterior margin.
The 1st antenna reaches back nearly to the posterior thoracic margin. On both sides segments 8 and 9 are completely and 9 and 10 partially fused, and segments 24 and 25 are completely fused. The mandible shows a complete absence of any biting jaw; the 2nd basal segment and the two rami appear to be identical with those of the female.

The 1st maxilla is much reduced. Lobes 1, 2 and 3 are small and are devoid of setae; lobe 4 bears 2 setae, one of which is very small; and lobe 5 carries one seta and 2 spines. The endopod bears 5 setae.

The maxilliped is not nearly so strong or well developed as in the female. The 1st basal segment is devoid of all setae; it has at its distal extremity a short spinous process and the rounded margin at the base of the spine is beset with a patch of short spinules. The 2nd basal segment bears on its anterior margin three setae which increase in length and size, and at the extreme end a single seta arises. The fringe of hair-like spines that is present on the proximal part of the anterior margin in the female is absent in this sex. The endopod consists of five segments bearing the following number of seta, 3, 3, 2, 2 and 3, on the 1st to 5th segments respectively.
The 1st swimming leg differs from the corresponding appendage in the female in that there is a clear separation of the 1st and 2nd segments of the exopod. In both male and female, a fland opens on the margin of segments 2 and 3.

In the 2nd swimming leg a trace of the line of separation between segments 1 and 2 of the exopod can be made out.

In the 5th pair of legs, the exopod of the right leg consists of two separate segments. The proximal segment is very long and tapers some-what towards the distal end. About one-fifth of its length from the distal end this segment bears a projecting triangular plate that is hollowed out into a groove. The distal segment tapers to a flexible point and about halfway along it there is a projecting lamella that corresponds to the groove on the proximal segment. The two segments are completely separate and appear to be freely movable on each other, and it appears probable that, when the distal segment is fully flesed, the lamella on the distal segments fits into the groove on the proximal segment and thus forms a very efficient grasping organ. In the left leg the exopod consists of three segments of which the 1st is equal to half the length of the whole ramus and is cylindrical. The two distal segments are subequal in length. At the distal end of the inner margin of segment 2 there is a small rounded projection that is fringed with hairs. The terminal segment tapers to a flexible point and a short distance on the proximal side of it is a sharp triangular point or spine; the inner aspect of the segment is thickly fringed with short hairs. In this species the endopod of the right leg extends well beyond the distal end of the endopod of the left leg.



Synonym (s)
Valdiviella insignis Farran, 1908
Valdiviella insignis Wolfenden, 1911
Valdiviella insignis Sewell, 1913
Valdiviella insignis With, 1915
Valdiviella insignis Lysholm and Nordgaard, 1921
Valdiviella insignis Sars, 1925

Common Name (s)
Economic Importance and Threats

Ecology

Biogeography


• Bay of Bengal INDIA (Record: 21/10/1911)

Literature Source(s)
  • 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 - http://www.marinespecies.org

Page last updated on:2010-07-20

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