Publishing Date: 2006

E-ISSN: 0255-7576

Volume 24 Issue 2


A faunistic and ecological investigation of marine nematode from the Arabian Gulf provides the first record of the genus Thalassironus De Man, 1889 with Thalassironus qatarense as new to science and was described from subtidal sediments from Arabian Gulf at Qatar. T. qatarense n.sp. is most similar to T. britannicus De Man, 1889 in the number and arrangement of cephalic sensilla but differs from T. britannicusgiven by Platt & Warwick (1983) in smaller and more robust body, in position of the cervical sensilla and in the smaller length of the spicules and gubernaculum. (L = 3.4-4.3 vs 6.5-7.5 mm; a = 48-69 vs 84-88; the posterior cervical sensilla are posterior to the buccal cavity in females of T. qatarense n. sp. vs the four cervical sensilla are located at the level of the buccal cavity in T. britannicus; spicules = 48-57.6 vs 62-72 µm; gubernaculums = 18-24.8 vs 30-38 µm). It also differs from T. britannicus given by Chitwood, 1960 in smaller body, oesophagus, tail and spicule length (L = 3.4-4.3 vs 7.2 mm; b =
6.5-7.7 vs 9.2; c = 27-29.8 vs 35, spicule length = 48-57.6 vs 72 µm). The new species is described and illustrated.