Three new species of free-living nematodes from inter-tidal sediments in southern New Zealand

Abstract

Abstract Three new species are described from sheltered intertidal sediments of Papanui Inlet, southern New Zealand. Microlaimus falciferus n. sp. is characterised by a cuticle with two lateral alae, the presence of pores between the cephalic setae, a strongly sclerotised and non-compartmentalised mouth cavity and scythe-shaped spicules with two sub-lateral pre-cloacal setae. This is the first species of the family Microlaimidae described as having lateral differentiation of the cuticle. Microlaimus falciferus n. sp. can also be differentiated from other Microlaimus species by the presence of two types of porids, i.e., pores and short hollow setae, as all other species of the genus possess only one type of porid (when present). Aponema subtile n. sp. is characterised by its slender form, relatively long tail, presence of longitudinal bars and lateral grooves on the cuticle and groups of short setae in the pre- and post-cloacal regions. It is similar to A. torosum in the structure of the male sexual organs but differs from the latter in the following ways: higher a values (30-40 vs 17-27); longer tail (5.4-7.8 vs 4-5 anal body diam. long) and a weakly sclerotised pharyngeal bulb that is never angular in appearance. Sabatieria annulata n. sp. is most similar to the cosmopolitan species S. punctata, the main difference being the absence of punctations in S. annulata n. sp. Sabatieria annulata n. sp. also has shorter spicules (34-36 vs 41-54 μm) and shorter gubernacular apophyses (14-16 vs 20-24 μm) than S. punctata.