New species and new records of Trigonalyidae (Hymenoptera) from Tibet, China

Abstract Two new species of Trigonalyidae are described from Tibet (SW China): Jezonogonalos nyingchiensis Chen & van Achterberg, sp. nov., and Taeniogonalos eurysoma Chen & van Achterberg, sp. nov. In total, seven species representing four genera are known from Tibet, and two of them are newly recorded from Tibet: Taeniogonalos bucarinata Chen, van Achterberg, He & Xu, 2014, and Teranishia crenulata Chen, van Achterberg, He & Xu, 2014.


Introduction
Trigonalyidae is a small family of Hymenoptera in its own superfamily Trigonalyoidea, with approximately 120 recognized species in 16 genera worldwide (Carmean and Kimsey 1998;Smith and Stocks 2005;Santos et al. 2012;Smith and Tripotin 2012;Chen et al. 2014;Yamane 2014;Smith and Tripotin 2015;Tan et al. 2017;Lelej 2019). The family name Trigonalidae and Trigonlyidae have been used by different authors, but we follow Weinstein and Austin (1991) and Lelej (2003) in using the family name as corrected by Krieger (1894) to Trigonalyidae; for the argumentation see Lelej (2003), and Engel and Lelej (2020).
The biology of trigonalid wasps is peculiar. Rather than laying their eggs directly on or in their host, females of these wasps lay thousands of minute eggs on foliage, which must be eventually consumed by caterpillars or sawfly larvae. Once inside the caterpillars or sawfly larvae, the wasp egg either hatches and attacks any other parasitoid larvae (wasps: Ichneumonidae or Braconidae; flies: Tachinidae) or it waits until the caterpillars or sawfly larvae are fed to a Vespidae larva, which it then attacks. Therefore, these wasps are hyperparasitoids or primary parasitoids, but extremely unusual among hymenopterans (Carmean and Kimsey 1998;Murphy et al. 2009).
The greatest diversity of this family occurs in tropical and subtropical regions. In fact, the family seems to be absent from arctic and alpine habitats (Carmean and Kimsey 1998), though they were found to be fairly common at 1300-1500 m altitude in the Qinling Mountains of NW China (Tan et al. 2017). Here we describe two new species and record two described species from the mountainous province of Tibet.

Material and methods
This work is based upon specimens in the following collections, with abbreviations used in the text: SYSBM, Sun Yat-sen University, The Museum of Biology, Guangzhou, China; ZJUH, Institute of Insect Sciences, Zhejiang University, Hangzhou, China. Morphological terminology generally follows Chen et al. (2014). Images and measurements were made using a Nikon SMZ25 microscope with a Nikon DS-Ri 2 digital camera system. Images were post-processed with Adobe Photoshop CS6 Extended. YPT stands for collected in yellow pan trap.

Diagnosis.
Antenna black and with 23-27 segments; area above supra-antennal elevations flat, more or less punctate, without protuberance between elevations and inner side of supra-antennal elevations flat, smooth and black; tyloids of male antenna present on 10 th -16 th segments, short and nearly circular or elliptical; occipital carina widened medio-dorsally; apical segment of labial palp widened and obtuse, more or less triangu-lar; vertex normal, at most with slight median depression dorsally; mandibles wide in anterior view and sublaterally attached to head; metanotum strongly convex and finely sculptured medially; anterior propodeal sulcus crenulate and medially widened; posterior propodeal carina curved and distinctly protruding and more or less separated from foramen medio-dorsally; fore wing with large dark patch below pterostigma; vein 1-SR of fore wing long; hind trochanter black or ivory; hind tarsus slightly or not modified; second and third sternites of female flat and moderately sclerotized and no protuberances; body without pale pattern, at most malar space and margins of basal metasomal sternites and tergites narrowly ivory, remainder black (Chen et al. 2014). Biology. Unknown. Collected in June-November. Distribution. China, Japan. Before this study, eight species of this genus had been described from China, with only one species recorded from Tibet. We describe here another species new to science from Tibet.

Jezonogonalos jiangliae Chen, van Achterberg, He & Xu, 2014 Figs 1-11
Jezonogonalos jiangliae Chen et al., 2014: 29-32 (diagnosis, description, distribution Notes. Jezonogonalos jiangliae was first described by Chen et al. (2014) based on a single male without complete antennae from Tibet. Based on the additional material, this species shows the following variations: male antenna with 25 or 26 segments, with tyloids present on 10 th -15 th or 11 th -16 th segments; clypeus usually entirely black, but sometimes partly ivory; second tergite sometimes with ivory spots latero-posteriorly. The female of this species is still unknown. As Chen et al. (2014) suggested, collection at the type locality and the use of COI ("barcoding") will recover the conspecific female. Diagnosis. Occipital carina very wide medio-dorsally, with pair of curved lamellae separated by a carina (Fig. 14); outer side of supra-antennal elevations subvertical, smooth, and elevations approximately 0.6 × as long as scapus (Fig. 14); frons densely punctate dorsally and laterally, largely smooth ventrally and medially (Fig. 13); supraantennal elevations largely ivory dorsally (Fig. 14); mandible mainly black, except dark brown base of teeth (Fig 13); metasoma dorsally largely smooth and largely black (Fig.  20); first tergite approximately 0.7 × as long as its apical width (Fig. 20); third sternite approximately 0.4 × as long as second sternite (Fig. 22).

Jezonogonalos nyingchiensis
Comments. This species is similar to J. shaanxiensis from Shaanxi (NW China) and it would run to that taxon (couplet 7) in the key of Tan et al. (2017), but can be distinguished by having the frons largely smooth medially and the mesopleuron mainly punctate-rugose, but narrowly smooth posteriorly.
Colour. Black; inner orbita narrowly ivory and connected to ivory malar space; pair of faint patches on clypeus, basal patch of mandible, large patch on supra-antennal elevations, large patch on anterior margin of pronotum, pair of elongate patches on middle lobe of mesoscutum anteriorly, pair of narrow lines near tegulae, epipleura of tergites, large patch apico-laterally on second tergite and narrow apical bands of sternites ivory; mandible teeth dark brown basally (Fig. 13); tegulae mainly dark brown; palpi dark brown; legs mainly black, but fore femur apico-ventrally brownish; pterostigma basally yellow, and remainder dark brown; large area below pterostigma dark brown and remainder of wing membrane subhyaline (Fig. 18).
Variations. Length of body 10.8-11.2 mm, of fore wing 8.9-9.4 mm; metanotum black or with pair of faint ivory spots medially; ivory patches of clypeus and mesoscutum rather small to large; length of vein 1-M of fore wing 1.

Diagnosis.
Antenna with 21-32 segments, often with a pale band in apical third of antenna and slender medially; male antenna without tyloids; supra-antennal elevations smooth and shiny, usually comparatively large, without depression dorsally and moderately to widely separated; vertex normal, at most with slight median depression dorsally; apical segment of labial palp widened and obtuse, more or less triangular; mandibles wide in anterior view and sublaterally attached to head; occipital carina usually narrow and smooth; mesoscutum and scutellum often smooth or sparsely punctulate, at most moderately punctate with wide smooth interspaces; metanotum concave latero-dorsally and often sculptured, matt and distinctly convex medially; anterior propodeal sulcus distinctly crenulate, rarely partly reduced; posterior propodeal carina curved and lamelliform; vein 1-SR of fore wing medium-sized to long; fore wing subhyaline, at most slightly infuscate below pterostigma in female; triangular dorso-apical part of hind trochanter separated by an oblique groove; fore trochanter subparallel-sided and distinctly longer than hind trochanter; hind tarsus slightly or not modified; second metasomal sternite and tergite flat in lateral view, weakly sclerotized and smooth; second sternite in ventral view flat medially or weakly convex and no medial elevation or teeth posteriorly; basal half of third sternite flat, without a distinct ledge anteriorly; fifth sternite of female straight or slightly emar-ginate medio-posteriorly; body often slender (including metasoma) and sometimes ichneumonid-like (Chen et al. 2014). Biology. Reared as hyperparasitoid of Tachinidae in caterpillars of the family Limacodidae (Carmean and Kimsey 1998;Murphy et al. 2009). Collected in May-August.
Distribution. Mainly East Palaearctic and Northeast Oriental regions, with a few species in East Afrotropical (including Madagascar), Neotropical and Nearctic regions. Chen et al. (2014) and Tan et al. (2017) reported eight species of Orthogonalys from China, with only one species from Tibet.

Diagnosis.
Antenna with 21-26 segments, without pale band and slender medially; male antenna with linear tyloids (= elevated elongate areas) on 11 th -16 th antennal segments; supra-antennal elevations smooth or punctate, without depression dorsally, remain far separated from each other medially and without horizontal "shelf " between antennal bases; temple usually punctate or reticulate-punctate and moderately shiny; occipital carina ending at hypostomal carina at level of mandibular base; vertex flattened, without median depression dorsally; apical segment of labial palp widened and obtuse, more or less triangular; mandibles wide in anterior view and sublaterally attached to head; mesoscutum and scutellum distinctly punctate or rugose; metanotum at least partly convex latero-dorsally and often sculptured; vein 1-SR of fore wing me-dium-sized to long; fore wing often with subapical dark patch or large part of fore wing dark brown; triangular dorso-apical part of hind trochanter separated by an oblique groove; fore trochanter subparallel-sided and distinctly longer than hind trochanter; hind tarsus slightly or not modified; propodeal foramen more or less arched dorsally and often with a lamelliform carina; second sternite convex in lateral view (but less so in males), strongly sclerotized and frequently densely punctate, sometimes with a medio-posterior elevation but without pair of small teeth; basal half of third sternite flat, without a distinct ledge anteriorly; hypopygium of female pointing anteriorly toward second sternite or straight down or pointing posteriad (Chen et al. 2014). Biology. Reared as hyperparasitoid of parasitoid wasps (Ichneumonidae and Braconidae) and parasitoid flies (Tachinidae) in caterpillars, but some species are primary parasitoids of pergid sawflies in Australia (Raff 1934;Carne 1969;He and Chen 1986;Weinstein and Austin 1995;Carmean and Kimsey 1998). Collected mainly in April-October, rarely in November or January.
Distribution. This genus occurs in all major regions, but is unknown from Europe and western Nearctic region. Most of the species occur in the East Palaearctic, Northeast Oriental, and Neotropical regions (Carmean and Kimsey 1998). Chen et al. (2014) reported two species (Taeniogonalos formosana (Bischoff 1913) and T. taihorina (Bischoff 1914)) from Tibet. Here we describe a third species new to science and report a fourth species from this region.
Colour. Black; outer orbita with pale yellow stripes, inner orbita with small patches near malar space (Figs 13, 14); mandibles largely dark brown, with basal patches; pair of elongate patches on middle lobe of mesoscutum anteriorly, pair of patches on antero-lateral margin of scutellum, two pairs of transverse patches on metanotum; palpi, and tegulae dark brown; posterior margin of tergites, 1 st and 2 nd sternites with ivory stripes (Fig. 33); legs mainly black with tarsi dark brown; pterostigma nearly black; apical half of marginal cell of fore wing largely infuscate as area below it, remainder of wing membrane subhyaline (Fig. 27).

Teranishia Tsuneki, 1991
Teranishia Tsuneki, 1991: 15-18;Lelej 1995Lelej : 12, 2003Carmean and Kimsey 1998: 73;Chen et al. 2014: 193-201 (diagnosis, key to species). Type species (by monotypy): Teranishia nipponica Tsuneki, 1991. Diagnosis. Antenna black and with 24-27 segments; male antenna without tyoloids; area above supra-antennal elevations flat, more or less punctate, with protuberance between elevations and inner side of supra-antennal elevations flat, smooth and black; occipital carina widened medio-dorsally; apical segment of labial palp widened and obtuse, more or less triangular; vertex normal, at most with slight median depression; mandibles wide in anterior view and sublaterally attached to head; anterior propodeal sulcus distinctly crenulate; metanotum strongly convex and finely sculptured medially; anterior propodeal sulcus crenulate and medially widened; posterior propodeal carina curved and distinctly protruding and more or less separated from foramen mediodorsally; fore wing with large dark patch below pterostigma; vein 1-SR of fore wing long; hind trochanter black, dark brown or ivory; hind tarsus slightly or not modified; second and third sternites of female flat and moderately sclerotized and no protuberances; body without pale pattern, at most malar space and margins of basal metasomal sternites and tergites narrowly ivory, remainder black (Chen et al. 2014). Biology. Unknown. Collected in June-September. Distribution. China, Japan. Chen et al. (2014) reported two species from China. Teranishia crenulata Chen, van Achterberg, He & Xu, is newly recorded from Tibet in this study.