Genus Okranema Greenslade & Nicholas, 1991

The genus Okranema was created by Greenslade & Nicholas (1991) and was named for its okra-like shape including two original descriptions: Okranema eileenae Greenslade & Nicholas, 1991 and Okranema militaris Greenslade & Nicholas, 1991 . It is distinguished from other Thoracostomopsidae genera by the combination of head shape, cuticle, shape of the mandibles and S-shaped gubernaculum, and by the short and broad tail. Mandibles are most similar to those found on Epacanthion .

Diagnosis from Smol et al. (2014): Body short, broad, slightly hook-shaped when preserved. Cuticle very thick and annulated, distinct shoulder at base of head capsule where the cuticle sharply increases in thickness. Head square. Lip flaps well-developed and with fine ridges forming striations along their edges; cephalic setae inserted just above base of head capsule; short subcephalic setae. Mandibular teeth S- or hook-shaped; mandibular columns distinct, arch anteriorly between teeth; labial setae fairly long but stout. Pharynx cylindrical; cardia pyriform. Female gonad to left of intestine. Spicules with thick walls, about as long as cloacal diameter; S-shaped gubernaculum; precloacal supplement absent. Caudal glands precaudally. Tail extremely short and broad. Marine.

Number of valid species: 2

1. Okranema eileenae Greenslade & Nicholas, 1991 (Australia, New South Wales)— type species

2. Okranema militaris Greenslade & Nicholas, 1991 (Australia, New South Wales)

Key for males of Okranema copied from Greenslade & Nicholas (1991):

1- Tail <2 abd in length, apical teeth closer together than half length of mandibular columns, columns nearly parallel.................................................................................................. O. militaris

- Tail <3 abd in length, tips of apical teeth further apart than half mandibular column length, columns markedly divergent towards apex and not parallel................................................................... O. eileenae