Linycus Cameron, 1903

Kikuchi, Namiki & Konishi, Kazuhiko, 2021, A taxonomic revision of the genus Linycus Cameron, 1903 from Japan, Zootaxa 4948 (4), pp. 546-558 : 548-549

publication ID	https://doi.org/ 10.11646/zootaxa.4948.4.3
publication LSID	lsid:zoobank.org:pub:404245B5-5C48-4156-95F8-71E9DE51517B
DOI	https://doi.org/10.5281/zenodo.4670558
persistent identifier	https://treatment.plazi.org/id/3011EC32-FFB6-7916-FF16-AD2FFBFAF14A
treatment provided by	Plazi
scientific name	Linycus Cameron, 1903
status

Treatment

Genus Linycus Cameron, 1903 View in CoL View at ENA

Linycus Cameron, 1903: 198 View in CoL [

Type species: Linycus rufipes Cameron, 1903 View in CoL ; monotypic]; Perkins, 1959: 67; Heinrich 1962: 777–783; Townes et al., 1965: 513; Townes & Townes, 1966: 273; Heinrich 1974: 178–179; Heinrich, 1977: 278–279; Tereshkin, 2009: 1454–1455.

Erythroischnus Cameron, 1904: 252 [

Type species: Erythroischnus annulicornis Cameron, 1904 ; monotypic].

Description based on Japanese species.

Head. Gena moderately narrowed behind eye in dorsal view; ocellar triangle weakly elevated above eyes; antennal sockets large, protruding anteriorly in dorsal view ( Figs 2-B View FIGURE 2 , 3-B View FIGURE 3 ). Internal margins of compound eyes parallel; antennal cavity of supra-antennal area expressed and polished; polished area of antennal cavity small; supra-antennal area with small and distinct tubercle between antennal sockets; supra-clypeal area rather convex, protruding anteriorly; clypeus small, moderately convex, transverse, with straight apical margin, clearly divided from supraclypeal area by furrow; anterior tentorial pits moderate, longish oval; labrum trapezoid shaped, with straight apical margin, strongly protruding from under clypeus ( Figs 2-A, C View FIGURE 2 , 3-A, D View FIGURE 3 ). Mandible slender, narrowed to apex, with small lower tooth ( Fig. 2-C View FIGURE 2 ). Malar space almost as long as mandible base ( Figs 2-A, C View FIGURE 2 , 3-A, D View FIGURE 3 ). Occipital carina complete, weakened above mandibular base; dorsomedian part of occipital carina angled ( Figs 2-B View FIGURE 2 , 3-B View FIGURE 3 ); hypostomal carina slightly widened near mandibular base. Maxillary palpus long, 2nd segment almost triangular, flat and not bulging.

Antenna. Flagella bristle-shaped, long and slender, not flattened.

Mesosoma. Collar of pronotum short, transverse furrow of pronotum not interrupted by keel ( Figs 2-D View FIGURE 2 , 3-C View FIGURE 3 ). Pronotal base without angular prominence, but somewhat angled ( Figs 2-E View FIGURE 2 , 3-D View FIGURE 3 ). Mesoscutum strongly convex, notauli weakly developed on anterior 1/3 ( Figs 2-D, E View FIGURE 2 , 3-D, D View FIGURE 3 . Scutellum highly elevated, dorsal surface moderately to strongly convex, with lateral carinae ( Figs 3-G, H View FIGURE 3 ). Prepectal carina complete; subalar ridge rather thin; sternaulus indistinct, developed on anterior 1/3; postpectal carina absent ( Figs 2-E View FIGURE 2 , 3-D View FIGURE 3 ). Hind margin of metanotum with a triangle projection on each side of postscutellum ( Figs 2-D View FIGURE 2 , 3-C View FIGURE 3 ). Propodeum with costula, often weak; juxtacoxal carina and pleural carina indistinct; areola usually wide, hexagonal, anterior margin broadly truncate; apex of second lateral area with small tubercle ( Figs 2-D, E View FIGURE 2 , 3-C, D View FIGURE 3 ). Propodeum short in profile ( Figs 2-E View FIGURE 2 , 3-D View FIGURE 3 ). Propodeal spiracle small, circular to rounded ( Figs 2-D View FIGURE 2 , 3-C View FIGURE 3 ).

Legs. Slender and long. Fore and mid tarsomeres 2–5 weakly flattened, widened to apex, and with fine short hairs; spines on each tarsomere 4 moderately short, developed ( Fig. 2-I View FIGURE 2 ).

Wings ( Fig. 4 View FIGURE 4 ). Areolet pentagonal ( Fig. 4-A View FIGURE 4 ) or quadrangular ( Fig. 4-B View FIGURE 4 ); single bulla on 1m-cu and 3rs-m, two bullae on 2m-cu; ramulus weakly developed. Hind wing with vein cu-a.

Metasoma. Amblypygous. Petiole in profile straight, flattened, clearly wider than deep, bending before base of postpetiole; in dorsal view, basal half weakly widened toward posterior; dorsomedian carina and dorsolateral carina present ( Figs 2-F, G View FIGURE 2 , 3-E, F View FIGURE 3 ). Gastrocoelus shallow; thyridium clearly developed and narrow ( Figs 2-F View FIGURE 2 , 3-E View FIGURE 3 ). Parathyridium normal, distinct ( Figs 2-F View FIGURE 2 , 3-E View FIGURE 3 ). Cercus with long setae; ovipositor sheath parallel sided with rounded apex, moderately long, and protruding behind apex of metasoma ( Figs 2-F, G View FIGURE 2 , 3-E, F View FIGURE 3 ).

Diagnosis. This genus can be distinguished from other genera of the tribe Platylabini by a combination of the following characteristics: surface of head dull; surpraclypeal area convex and protruding anteriorly; spines on each tarsomere 4 normally developed; costula present; propodeal spiracle circular; gastrocoelus shallow; cercus with long setae; ovipositor sheath rather long.

Distribution. Japan (2 spp.); Western Palearctic (3 spp.), Eastern Palearctic (2 spp.), Nearctic (4 spp.), Oriental (4 spp.) and Neotropical (1 sp.) regions.

Remarks. This genus resembles Cyclolabus in the supra-clypeal area rather convex, protruding anteriorly, and circular propodeal spiracle, but can be distinguished by the shape of gastrocoelus, and somewhat developed spines on tarsomeres. The following records are the first records of this genus from Japan.

Kingdom	Animalia
Phylum	Arthropoda
Class	Insecta
Order	Hymenoptera
Family	Ichneumonidae