Chaetonotus triradiatus   Rao,  1991 (Gastrotrich)
Organism information awaits expert curation

Size: Length 120-160 µm excluding caudal furca and maximum width 40-45 µm.

Body is typically of chaetonotoid appearance, with a distinct head, neck, trunk and caudal furca. The head is 5-lobed, 30-35 µm in maximum width and bears 4 groups of tactile cilia on the lateral edges. The neck is about 30 µm at its maximum width. Trunk is widest at the mid-body region. Caudal furca are conical, 20 µm long and carry an adhesive tube 10 µm long.

The cuticular armature consists of simple spines arising from triradiate scales 3-6 µm in size. The scales have pointed anterior and lateral tips, while the lateral and posterior edges have concave borders. The spines arise on the posterior border of the scales. The scales and spines increase in size gradually from the anterior region to the mid-trunk region and then decrease posteriorly. Ventral ciliation occurs in two longitudinal patches, one on either side of the digestive tract. The mouth is terminal and 8 µm in width. Pharynx is 40 µm long, with a distinct posterior bulb. The gut following the pharynx is undifferentiated and 95 µm long. Anus is subterminal and opens on the dorsal surface 5 µm from the posterior border.

A single dorsal ovum 45 x 30 µm in size was observed in a mature specimen.

Synonym (s)

Common Name (s)
Economic Importance and Threats

Habitat:  Sandy, Coastal


• Lakshadweep, Agatti (Lat: 10.85) (Long: 72.18) INDIA (Record: 08/02/1987, 11/02/1987, 12/02/1987) (Depth: 0.05 mts)
• Lakshadweep, Agatti INDIA

Literature Source(s)
  • Zoological Survey of India (Eds) (1991) Animal resources of India (Protozoa to Mammalia) ZSI 1-694 Available at - NCL, Pune
  • Society for the Management of European Biodiversity Data (2009) World Register of Marine Species (WoRMS) Available at -
  • Rao, GC (1991) Meiofauna State fauna series 2: Fauna of Lakshadweep ZSI, Calcutta 41-135 Available at - NIO, Goa
  • Priyalakshmi, G and Menon, NR (2008) Indian marine Gastrotricha Available at -

Page last updated on:2010-11-22

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