Gauldiana Khalaim & Ward, 2018

Khalaim, Andrey I. & Ward, Darren F., 2018, Tersilochinae (Hymenoptera: Ichneumonidae) from New Zealand. Part 1. Generic key and three new genera, Zootaxa 4425 (1), pp. 41-77 : 66-67

Genus Gauldiana Khalaim & Ward , gen. nov.

Type species: Zealochus postfurcalis Khalaim, 2006 .

Diagnosis. Small to moderate sized species with body length 2.3–5.0 mm and fore wing length 2.1–4.1 mm.

Head, mesosoma and first metasomal tergite (except apical edge of postpetiole) very evenly granulate and dull, impunctate; sometimes vertex and genae with granulation shallow, weakly shining. Head in dorsal view transverse, rounded behind eyes. Clypeus lenticular, usually with lower margin slightly truncated centrally, or in G. triangulata subtriangular. Mandibles slender, with upper tooth clearly longer than the lower, in G. triangulata distinctly twisted. Eye surface glabrous. Occipital carina complete. Hypostomal carina absent. Flagellum with 13–21 flagellomeres, in female usually clavate apically.

Mesosoma with notauli usually weak and short, or vestigial, or absent. Foveate groove absent. Propodeum with weak transverse carina, mediodorsally usually without carinae, with same evenly granulate structure as on dorsolateral sides, or rarely with a vestigial median carina; apical area distinctly elongate, 1.3–1.8× as long as maximally broad, suboval.

Fore wing with vein 2m-cu interstitial or postfurcal; vein 2m-cu always present, though widely unpigmented anteriorly. Hind wing with vein cu1&cu-a weakly to strongly reclivous. Legs slender; hind coxa of female with conspicuous ridge on ventral surface ( Fig. 107 , arrow).

Metasoma with first tergite in dorsal view weakly to moderately broadened posteriorly, usually subcylindrical, or G. triangulata depressed. Glymma entirely absent. Thyridial depression very shallow, often indistinct, as long as broad or slightly elongate. Female with ovipositor slender for its entire length, weakly to strongly upcurved, often with apex conspicuously stronger upcurved than basal 0.8, with neither dorsal nodus nor subapical notch or depression, but with very fine teeth on apex of lower valve.

Comparison. Gauldiana is readily distinguished from other New Zealand genera by the following unique features: ovipositor very slender for its entire length, without trace of a dorsal subapical notch or nodus ( Figs 92 , 97 , 103 ); apical area of propodeum very narrow, always elongate, suboval, less than half of propodeum maximum width ( Figs 91 , 96 , 102 , 107 ); hind coxa of female with a ventral longitudinal ridge ( Fig. 107 , arrow); and the first tergite entirely evenly granulate, without any vestiges of glymma ( Figs 98, 103 , 108 ).

The genus is also characterized by the following characters: flagellum in female usually clavate ( Figs 88 , 95 , 100, 101 , 104 ); notaulus absent (except G. triangulata ); foveate groove of mesopleuron absent ( Figs 93 , 103 , 109 ); propodeum with only transverse carina, mediodorsally usually evenly granulate ( Figs 91 , 96 , 102 ), or rarely with a weak basal keel ( Fig. 107 ); head and mesosoma evenly granulate, impunctate. Species of the genus, excepting highly specialized G. triangulata , are very uniform and are not easy to identify.

Etymology. Named in honour of the British entomologist Ian D. Gauld in recognition of his great contribution to the study of Ichneumonidae of the world. This work is partially based on his preliminary identifications of New Zealand Tersilochinae . Gender feminine.

Remarks. Gauldiana is endemic to New Zealand where nine species are recognized; all except G. postfurcalis (Khalaim) , comb. nov. are described here as new. Large numbers of individuals of G. triangulata have been reared from the scolytid-infested wood of Pseudopanax simplex (Araliaceae) and another species, G. nigra , was reared from the weevil Phorostichus linearis (Curculionidae) in Astelia trinervia (Asteliaceae) .

Figures

FIGURES 104–109. Gauldiana triangulata sp. nov., paratype, female (104–108) and male (109): 104—head with antenna, lateral; 105—head, front; 106—head and mesoscutum, dorsal; 107—propodeum and hind coxae, dorsolateral; 108—first tergite, lateral; 109—mesosoma and metasoma, lateral.

FIGURES 88–92. Gauldiana arantia sp. nov., paratype, female: 88—head with antennnae, lateral; 89—head, frontolateral; 90—head and mesoscutum, dorsal; 91—apex of mesosoma and base of metasoma, dorsal; 92—metasoma with mid and hind legs and ovipositor, lateral.

FIGURES 93–97. Gauldiana arantia sp. nov., paratype, male: 93—body, lateral. Gauldiana aspiringa sp. nov., paratype, female: 94—head, front; 95—head with antenna, lateral; 96—apex of mesosoma and base of metasoma, dorsal; 97—metasoma with hind leg and ovipositor, lateral.

FIGURES 98–103. Gauldiana dubia sp. nov., paratype, female: 98—body, lateral; 99—head with antenna, lateral. Gauldiana kaweka sp. nov., paratype, female: 100—head with antenna, lateral. Gauldiana minuta sp. nov., paratype, female: 101—head with antenna, lateral; 102—propodeum, dorsolateral; 103—apex of mesosoma and metasoma with ovipositor, lateral.