Odontophora Bütschli, 1874

Ansari, Kapuli Gani Mohamed Thameemul, Lyla, Somasundharanair & Khan, Seyd Ajmal, 2018, New distributional records of free-living marine Nematodes from Indian waters IV. Linhomids and Axanolaimids, Records of the Zoological Survey of India 118 (4) : -

Genus Odontophora Bütschli, 1874

8. Species Odontophora rectangula Lorenzen, 1971

Material examined: 21 males and 14 females collected from Cuddalore – SIPCOT 30-50m,> 176m depths (19.12.2008); Cheyyur 30-50m, 76-100m, 101-150m, 151- 175m> 176m depths (18.12.2008) and Singarayakonda 30-50m depth (15.12.2008).

de Man ratio: a b c Male: 43.54±1.07 10.11±0.63 12.17±0.68

(42.81-44.28) (9.78-10.55) (11.86-12.89) Female: 41.12±0.44 9.92±0.14 11.89±0.21

(40.49-41.66) (9.66-10.04) (11.66-12.10)

Description: Body length 1.2-1.9mm in male and 1.6-2mm in female. Maximum diameter 26-34µm in male and 28- 43µm in female. Cuticle finely striated. Six cephalic papillae. Four cephalic setae (11-18µm). Eight 14-15µm subcephalic setae in a cervical setae. Loop-shaped amphids (5-9µm in diameter). Buccal cavity (22-28µm) long. Oesophagus widens towards the base (114-134µm in male and 120-131µm in female) without posterior bulb. Tail conical (4.2-4.9a.b.d. in male 4.1-4.6a.b.d. in female) with three long terminal setae. Spicules 21-27µm. Gubernaculum with 7-9µm dorsal apophysis. Two ovaries. Vulva present at 60- 66% of body length ( Figure 8 ).

Feeding type: The specimens showed large buccal cavity that is not armed with teeth. According to the classification of buccal cavity by Wieser (1953), this species is a nonselective deposit feeder (1B).

Habitat: Sandy and silty sediments.

Distribution: India: Cuddalore – SIPCOT, Cheyyur and Singarayakonda. Elsewhere: Helgoland, West Scotland and North Ireland ( Hansson, 1998); England ( Warwick et al., 1998) and European waters ( De Smet et al., 2001; Medin, 2011).

Remarks: The specimens examined conformed well to the earlier description of Warwick et al. (1998) except for the smaller body size. The total body length described was

2.8-3.1mm and tail length 3-4.5a.b.d. The body length of the specimen studied at present was found smaller being

1.2-1.9mm and the tail length 4.2-4.9a.b.d. in male and in female 1.6-2mm body length and tail length 4.1-4.6a.b.d. This is the first record of the species from the Indian waters.

Figures

Figure 8. Odontophora rectangula Lorenzen, 1971 a) entire male b) female head, c) entire female, d) male head, e) male tail, f) female tail.