A review of the genus Tripylina Brzeski, 1963 (Nematoda: Triplonchida), with descriptions of five new species from New Zealand

Tripylina contains six accepted species. Morphologically, five new species can be briefly characterized as follows: T. tearoha sp. nov., T. manurewa sp. nov. and T. tamaki sp. nov. each have a single ventromedian seta and two pairs of lateral setae in the cervical region; T. tearoha sp. nov. differs from T. tamaki sp. nov. by de Man’s Index a (25–30 vs 20– 23), and differs from T. manurewa sp. nov. by the distance of the ventromedian cervical seta from the head end (62–77 vs 78–86 μm). T. manurewa sp. nov. differs from T. tamaki sp. nov. by de Man’s Index a (24–29 vs 20–23). Molecularly, these three new species can be differentiated by SSU & LSU analysis. Tripylina yeatesi sp. nov. and T. kaikoura sp. nov. are characterised by relatively long bodies, and the absence of ventromedian cervical setae; Tripylina yeatesi sp. nov. differs from T. kaikoura sp. nov. by de Man’s Indices: a (29–30 vs 22–23), b (5.8–6.0 vs 6.0–6.2), c (18–26 vs 14–16) and c’ (2.0–2.6 vs 2.7–3.0), respectively. Among the six previously described species, the main distinguishing features for T. arenicola and T. ursulae are their subventral stoma denticles lying posterior to the dorsal tooth, which differentiates them from T. longa, T. macroseta, T. sheri and T. stramenti. All published species also can be differentiated by: body length; values of De Man’s Indices a, b, c, c’ and V; presence or absence of setae and setal positions. A key is provided for all eleven species of the genus.