New species of nematode from the south eastern Arabian Sea

Phylum: Nematoda Rudolphi, 1808

Class: Chromadorea

Order: Chromadorida Filipjev, 1929

Family: Paramicrolaimidae Lorenzen, 1981

Paramicrolaimus damodarani Jacob, Jaleel & Vijayan, 2015

Collection: Continental margin of south eastern Arabian Sea – off Cape Comorin, 7° 09’ 12” N, 77° 19’ 14” E, 207 m, 21.04.2005 (FORVSS 233); off Kannur, 11° 45’ 02” N, 74° 41’ 47” E, 95 m, 11.02.2012 (FORV;SS 295). Smith-McIntyre grab.

Voucher No.: IO/SS/NEM/00021 (FORV Referral Centre, CMLRE, Kochi)

Description: Finely striated cylindrical body with thick cuticle. Labial sensilla papilliform, barely visible. Cephalic setae in two separate circles (6+4), almost equal in size. Conspicuous amphids with thick wall, ventrally coiled, spiral, with a loop, transversely oval-shaped with a small dorsal limb. Buccal cavity narrow, tubular, with two denticle-like projections. Spicules paired, strongly arcuate, proximally cephalate with a distinct central keel. Gubernaculum simple, plate-like, with a lateral wing in the middle part. Seven cuticularised, protruding, ventrally placed precloacal supplements. Males with two opposed testes. Ventrally placed pre-anal papillae present in males. Tail conoid with a cuticularised terminal spinneret.

Biological association: None.

Remarks: No Females found. Sediment texture: silt with low percentages of clay, bottom temperature 26.6°C, salinity 35.65 psu, dissolved oxygen concentration 2.98 ml/l.

Distribution: Continental margin of south-eastern Arabian Sea.

Distribution map:

Identified by: Jini Jacob

Publication:  Jacob J, Abdul Jaleel K U, Vijayan A K. 2015. A new species of the rare nematode genus Paramicrolaimus Wieser, 1954 (Chromadorida: Paramicrolaimidae) from the south eastern Arabian Sea. Zootaxa, 3904 (4): 563–571.