Trieces Townes, 1946

Ranjith, A. P. & Priyadarsanan, Dharma Rajan, 2022, First description of the metopiine genus Trieces Townes, 1946 (Hymenoptera: Ichneumonidae) from the Indomalayan region with three new species from India, European Journal of Taxonomy 794 (1), pp. 1-17 : 3-4

publication ID	https://doi.org/ 10.5852/ejt.2022.794.1649
publication LSID	lsid:zoobank.org:pub:ACE4FEB8-3644-4296-9C87-F9A7C1C65CD3
DOI	https://doi.org/10.5281/zenodo.6038088
persistent identifier	https://treatment.plazi.org/id/03EAF724-FF9F-FF8E-FDA6-FDE4FAD8F86F
treatment provided by	Felipe
scientific name	Trieces Townes, 1946
status

Treatment

Genus Trieces Townes, 1946 View in CoL View at ENA

Trieces Townes, 1946: 60 View in CoL .

Type species: Exochus texanus Cresson, 1872 .

Diagnosis

Eyes glabrous or sparsely setose, slightly emarginated near antennal torulus ( Figs 1B View Fig , 3B View Fig , 5B View Fig ). Face often wider than long ( Figs 1B View Fig , 3B View Fig , 5B View Fig ), rarely longer than wide, sometimes narrowing posteriorly ( Figs 3B View Fig , 5B View Fig ). Interantennal process distinct, acute ( Figs 1B View Fig , 3B View Fig , 5B View Fig ). Clypeus transverse, separated from face by shallow transverse impression, apical margin sharp and more or less truncate, weakly convex or slightly concave. Mandible often with upper and lower teeth, rarely lower tooth absent. Frons depressed, without midlongitudinal lamella ( Figs 1C View Fig , 3C View Fig , 5C View Fig ). Temple not bulged behind eyes in dorsal view ( Figs 1C View Fig , 3C View Fig , 5C View Fig ). Pronotum evenly convex without impression. Propleuron weakly swollen ( Figs 1E View Fig , 3E View Fig , 5E View Fig ). Mesonotum without notauli ( Figs 1F View Fig , 3F View Fig , 5D View Fig ). Scutoscutellar groove small, smooth ( Figs 1F View Fig , 3F View Fig , 5D View Fig ). Scutellum with distinct lateral carina ( Figs 1F View Fig , 3F View Fig , 5D View Fig ). Mesopleuron without sternaulus ( Figs 1E View Fig , 3E View Fig , 5E View Fig ). Epicnemial carina present and complete ( Figs 1E View Fig , 3E View Fig , 5E View Fig ). Mesopleural suture absent ( Figs 1E View Fig , 3E View Fig , 5E View Fig ). Metapleuron with or without longitudinal wrinkles and posterior slit ( Figs 1E View Fig , 3E View Fig , 5E View Fig ). Propodeum with distinct pleural carina and a pair of submedial carinae, posterior transverse carina absent ( Figs 2A View Fig , 4A View Fig , 5F View Fig ). Fore and mid tarsal claws pectinate, hind tarsal claw simple. Fore wing without areolet ( Figs 2B View Fig , 4B View Fig , 6C View Fig ). Fore wing vein 1cu-a interstitial to postfurcal ( Figs 2B View Fig , 4B View Fig , 6C View Fig ). Hind wing vein CU1b absent. Metasomal tergites without laterotergites ( Figs 2C View Fig , 4D View Fig , 6A View Fig ). First metasomal tergite broad posteriorly with dorsal and dorso-lateral carinae ( Figs 2D View Fig , 4C View Fig , 6B View Fig ), and rarely with ventro-lateral carina ( Fig. 2C View Fig ). Spiracle of first metasomal tergite at anterior ⅓ rd ( Figs 2C View Fig , 4D View Fig , 6A View Fig ). Second metasomal tergite with midlongitudinal and lateral carinae ( Figs 2D View Fig , 4C View Fig , 6B View Fig ). Third metasomal tergite often with complete midlongitudinal carina and lateral carina ( Figs 2D View Fig , 4C View Fig , 6B View Fig ). Fourth metasomal tergite often without lateral carina ( Figs 2C View Fig , 4D View Fig , 6A View Fig ). Ovipositor slender apically ( Fig. 4D View Fig ).

Distribution

Though Yu et al. (2016) listed this as a cosmopolitan genus, there were no described species of this genus so far from the Indomalayan region.

Biology

Larval-pupal endoparasitoids of Lepidoptera particularly Tortricidae and Yponomeutidae ( Gauld et al. 2002; Broad et al. 2018).

Key to separate Trieces Townes, 1946 from Chorinaeus Holmgren, 1858

1. Mesopleuron with mesopleural suture ( Fig. 7A, C View Fig ); lateral longitudinal carina only present on metasomal tergite 1 and base of second metasomal tergite ( Fig. 7A, D–F View Fig ); pronotum with dorsal longitudinal depression ( Fig. 7B View Fig ) (weak in C. brevicalcar Thomson, 1887 View in CoL ) ........... Chorinaeus Holmgren, 1858 View in CoL

– Mesopleuron without mesopleural suture ( Figs 1E View Fig , 3E View Fig , 5E View Fig ); lateral longitudinal carina present on metasomal tergites 1–3 (absent in T. ranjithi ) ( Figs 2D View Fig , 4C View Fig , 6B View Fig ); pronotum without dorsal longitudinal depression (weakly present in T. flabenis Gauld & Sithole, 2002 View in CoL ) .................. Trieces Townes, 1946 View in CoL

Key to the Palearctic and Oriental species of Trieces Townes, 1946 ( onitis group)

1. Metapleuron without posterior slit-like depression ............................... other Trieces species groups

– Metapleuron with distinct posterior slit-like depression ( Figs 1E View Fig , 3E View Fig , 5E View Fig ) ........................................ ........................................................................................................................2 ( Trieces onitis View in CoL group)

2. Occipital carina absent; ocellar area elevated; face black; metapleuron glabrous or sparsely setose ........................................................................................................................................................... 3

– Occipital carina present ( Figs 1C View Fig , 3C View Fig , 5C View Fig ); ocellar area flat; face yellow or with brownish patches ( Figs 1B View Fig , 3B View Fig , 5B View Fig ); metapleuron densely or moderately setose ( Figs 1E View Fig , 3E View Fig , 5E View Fig ) ........................... 4

3. Face as wide as long; antenna with 18–19 flagellomeres; first flagellomere 1.3× as long as wide [ Japan and Russia] ........................................................................... Trieces hokkaidensis Kusigemati, 1967 View in CoL

– Face wider than long; antenna with 22–23 flagellomeres; first flagellomere 1.6 × as long as wide [ Japan and Russia] ................................................................ Trieces mandiblaris Kusigemati, 1971 View in CoL

4. Face completely yellow without brown patches ( Fig. 1B View Fig ); mandible with only upper tooth ( Fig. 1D View Fig ); antenna with 19 flagellomeres; first metasomal tergite with distinct wide, smooth longitudinal groove laterally ( Fig. 2C View Fig ); fore wing vein 1cu-a interstitial ( Fig. 2B View Fig ); temple posterior half yellow; mandible, scape and pedicel yellowish brown [ India] ..................................................... Trieces irwini sp. nov.

– Face yellow with midlongitudinal brown patches or entirely black with yellow spot antero-medially ( Figs 3B View Fig , 5B View Fig ); mandible with upper and lower teeth; antenna with 20–33 flagellomeres; first metasomal tergite without longitudinal groove laterally, if present then indistinct ( Figs 4D View Fig , 6A View Fig ); fore wing vein 1cu-a postfurcal ( Figs 4B View Fig , 6C View Fig ); temple posterior half black; mandible, scape and pedicel dark brown ................................................................................................................................................ 5

5. Mesopleuron without longitudinal wrinkles posteriorly; metapleuron densely setose; propleuron densely setose; area superomedia smooth [ Japan, Russia and South Korea] ..................................... .................................................................................................... Trieces homonae Kusigemati, 1967 View in CoL

– Mesopleuron with longitudinal wrinkles posteriorly ( Figs 3E View Fig , 5E View Fig ); metapleuron only posteriorly setose, rest glabrous ( Figs 3E View Fig , 5E View Fig ); propleuron glabrous ( Figs 3E View Fig , 5E View Fig ); area superomedia with wrinkles ( Figs 4A View Fig , 5F View Fig ) ..................................................................................................................................... 6

6. Temple longer than transverse diameter of eye in lateral view; antenna with 33 flagellomeres; face black with yellow spot antero-medially; midlongitudinal carina of third metasomal tergite 0.7 × as long as tergite [ South Korea] .................................................... Trieces koreanus Choi & Lee, 2016

– Temple shorter than transverse diameter of eye in lateral view ( Figs 3E View Fig , 5E View Fig ); antenna with 20–23 flagellomeres; face yellow with brown longitudinal patch medially; midlongitudinal carina of third metasomal tergite 0.5 × as long as tergite ( Figs 4C View Fig , 6B View Fig ) .................................................................. 7

7. Metapleural slit short, isolated ( Fig. 3E View Fig ); metapleuron longitudinally striated ( Fig. 3E View Fig ); mesopleuron and propodeum distantly punctate ( Figs 3E View Fig , 4A View Fig ); submedial carinae of first metasomal tergite parallel posteriorly ( Fig. 4C View Fig ) [ India] ......................................................................... Trieces isolatus sp. nov.

– Metapleural slit long, curved ( Fig. 5E View Fig ); metapleuron basal half smooth ( Fig. 5E View Fig ); mesopleuron and propodeum closely punctate ( Figs 5E, F View Fig ); submedial carinae of first metasomal tergite narrowing posteriorly ( Fig. 6B View Fig ) [ India] ...................................................................... Trieces orientalis sp. nov.