Genus Ingenia Gerlach, 1957

Diagnosis (modified based on Smol et al. 2014) Cuticle with very fine transverse striations. Lips high. Anterior sensilla in two circles: six long inner labial setae; six very long and jointed outer labial setae and four short and thin cephalic setae in one circle. Amphids in subventral position. Buccal cavity large, consisting of only one part with a large, sharply pointed dorsal tooth and two smaller ventrosublateral teeth. Females didelphic-amphidelphic with antidromously reflexed ovaries. Males with single and outstretched testis.

Remarks. Ingenia is morphologically similar to Bathylaimus Cobb, 1894 in outer labial setae jointed, amphideal fovea unispiral, buccal cavity large, generally with three teeth and males with large gubernaculum. Ingenia differs from Bathylaimus mainly based on buccal cavity that presents only one part in Ingenia while it has two parts in Bathylaimus . According to description of I. communis by Gagarin and Thanh (2007), this species presents a buccal cavity with paired stomal pockets, which conforms to character of Bathylaimus . Thus, Ingenia communis Gagarin & Thanh, 2007 is transferred here to Bathylaimus as Bathylaimus communis comb. n.