Key to genera of Tersilochinae occurring in New Zealand

1. Fore wing with veins Rs+2 r and Rs meeting at obtuse angle (Figs 12–16). Head with foramen magnum unusually high, at or above level of upper margin of eye (Figs 60, 63, 66, 71). Antennae inserted low down, at or below level of centre of eye (Figs 60, 63, 66, 71). Mesosoma sometimes strongly compressed (Figs 62, 70). Female with upper valve of ovipositor with a steplike nodus (Figs 64, 68). Male genital capsule unusually large (Fig. 76).......................... Barycnellus gen. nov.

- Fore wing with veins Rs+2 r and Rs meeting at right angle (Figs 10, 11, 17–20). Head with foramen magnum not unusually high, only slightly above centre, below level of upper margin of eye. Antennae inserted at or above level of centre of eye. Mesosoma weakly compressed or subcylindrical. Ovipositor without a step-like nodus, often with a deep to very shallow subapical notch. Male genital capsule not unusually large......................................................... 2

2. Mandibles strongly twisted, so that when closed in front view they appear unidentate. Ovipositor apex with a distinctive double nodus............................................................................. Zealochus Khalaim

- Mandibles not or weakly twisted (except G. triangulata), always with lower tooth visible when they are closed so they are clearly bidentate. Ovipositor various, never with an apparent double nodus........................................ 3

3. Propodeum with apical area narrow, distinctly elongate (Figs 91, 96, 102). Foveate groove of mesopleuron completely absent (Figs 93, 103, 109). First tergite without any trace of glymma (Fig. 108). Ovipositor unusually slender, proximally straight, with distal end up-curved, without any trace of a subapical notch or nodus (Figs 92, 97). Hind coxa of female with a conspicuous median ventral ridge (Fig. 107)....................................................... Gauldiana gen. nov.

- Propodeum with apical area wider, as long as broad or transverse (Figs 41, 47, 86). Foveate groove of mesopleuron present or absent. First tergite with or without glymma. Ovipositor basally normally stout, sometimes evenly tapered towards distal end, but never entirely slender throughout, and usually with a nodus and/or a shallow to deep dorsal subapical notch or depression. Hind coxa of female unspecialized........................................................................ 4

4. Fore wing with vein 2m-cu distinctly postfurcal (Fig. 28). Propodeum with more or less distinct basal keel (Fig. 86). First tergite smooth and shining, round in cross-section, without any trace of glymma (in the New Zealand species)....................................................................................................... Diaparsis Förster

- Fore wing with vein 2m-cu antefurcal or interstitial. Propodeum usually with either a pair of basal carinae, or with a broad furrow or shallow impressed rugose area along midline in front of transverse carina. First tergite usually extensively striate or granulate, with shallow to deep glymma.................................................................... 5

5. Fore wing with vein 2m-cu distinctly antefurcal (Figs 10, 11). Ovipositor with a broad and moderately deep subapical notch, with a slightly swelling on lower valve just before the narrowed apex (Figs 43, 51, 57). Antennal flagellum long and slender, with 21 or more flagellomeres (Figs 38, 45, 52). Body length 4.0– 4.7 mm ....................... Aotearoazeus gen. nov.

- Fore wing with vein 2m-cu interstitial or slightly antefurcal. Ovipositor with a shallow weak subapical depression, without a swelling on lower valve before narrowed apex. Antennal flagellum short, with less than 20 flagellomeres. Body length 1.7–3.5 mm .............................................................. undescribed genus (will be revised in Part 2)