Valdiviella ignota   Sewell,  1929 (Copepod)
Organism information awaits expert curation
Class: Maxillopoda

Size (male): 8.7-9 mm

The proportional lengths of the cephalothorax and abdomen are as 250 to 97, so that the abdomen is contained 2.6 times in the length of the anterior region.

At the extreme anterior end is a small projection which bears a pair of minute hairs. The rostrum is not so strong. The posterior thoracic margin is produced backwards in a flap that covers half the length of the 1st abdominal segment, and at the postero-dorsal angle of this flap is a small spine that is directed backwards and upwards. The head and 1st thoracic segment are fused but traces of the line of fusion can be seen. Thoracic segments 4 and 5 are fused.

The abdomen consists of five segments. Segments 2, 3 and 4 are armed across the dorsal aspect with a row of fine spines that runs along the posterior margin. The furcal rami are divergent and the outer seta is extremely small.

The 1st antenna reaches back to the posterior thoracic margin. The 8th and 9th segments are completely fused and there is a partial fusion of the 10th segment also. The 24th and 25th segments are fused.

In the 2nd antenna, the 1st basal segment bears a row of long hairs.
Mouth-parts are reduced. In the mandible the biting process has been completely suppressed; the 2nd basal segment bears no seta; the exopod bears 8 setae on its terminal segment and 3 on the distal joint. In the 1st maxilla the biting lobe is reduced and bears no setae; the inner lobe is also devoid of setae; the 2nd basal segment carries 2 very small setae and the endopod 3 comparatively long ones; the outer lobe bears 11 setae of which the 1st is very small.

The 1st swimming leg both basal segments are fringed on their inner margins with long hairs; basal 2 bears a seta at its distal inner angle. The exopod consists of three segments but the line of separation between the 1st and 2nd segments is incomplete. The endopod consists of a single segment; on the outer margin there is a rounded swelling that extends across the surface of the segment and on the margin of this swelling four glands appear to have their orifices; there is a small patch of minute hairs on the surface.

Synonym (s)

Common Name (s)
Economic Importance and Threats



• 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 -

Page last updated on:2010-07-20

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