Casinaria onyx, Vas, 2019

Vas, Zoltán, 2019, New Species And New Records Of Ichneumon Wasps From The Eastern Mediterranean And The Black Sea Regions (Hymenoptera: Ichneumonidae), Acta Zoologica Academiae Scientiarum Hungaricae 65 (1), pp. 19-30 : 21-24

Casinaria onyx sp. n.

( Figs 1–3 )

Type material – Holotype: female, Georgia (Abkhazia) [on label: USSR, Georgia], Naa, Kodori Valley , 25.V.1975, leg. S. Tóth, specimen card-mounted, Id. No. HNHM-HYM 153072 . – Paratype: female, Georgia (Abkhazia) [on label: USSR, Georgia], Kelasuri Valley, 21.V.1975, leg. L. Zombori, specimen card-mounted, Id. No. HNHM-HYM 153073 . The holotype and the paratype are deposited in the Hymenoptera Collection of the Hungarian Natural History Museum (Budapest, Hungary).

Diagnosis – Among the Western Palaearctic species of Casinaria Holmgren, 1859 the new species most resembles to C. pallipes Brischke, 1880 , or C. hinzi Riedel, 2018 . C. onyx sp. n. can be easily separated from C. pallipes Brischke, 1880 by bent out genal carina, lack of propodeal carinae, more slender second tergite, number of flagellomeres and colouration of trochanters and trochantelli. The new species can be easily distinguished from C. hinzi Riedel, 2018 by yellow mandible, tegula and trochantelli, stouter second tergite, number of flagellomeres, and the deeper and more strongly striated propodeal impression. Among the Eastern Palaearctic and Oriental species of the genus the new species is most similar to C. arjuna Maheshwary et Gupta, 1977 , however, C. onyx sp. n. primarily differs from that species by yellow mandible and tegula, strong pleural carina, and colouration of fore and middle legs.

Description – Female ( Figs 1–3 ). Body length ca 7 mm, fore wing length ca 5 mm.

Head: Antenna with 31 flagellomeres; basal flagellomeres relatively slender, first flagellomere 3× as long as wide apically; preapical flagellomeres square. Head coarsely granulate and densely punctate, matte, with relatively long, dense, whitish hairs. Temple (gena) short, strongly and almost rectilinearly narrowed behind eye. Ocelli relatively small, ocular-ocellar distance 0.9–1× as long as ocellus diameter, posterior ocellar length 1.4× as long as ocellus diameter. Inner eye orbits indented and convergent ventrally. Face flat in profile, narrowed ventrally, minimal width of face 0.65× as long as eye length and 0.85× as long as width of frons. Clypeus very weakly separated from face, weakly convex in profile, apical margin convex, sharp. Genal carina (ventral part of occipital carina) distinctly bent outward ventrally, reaching hypostomal carina very slightly behind mandible base in 80–90° angle. Hypostomal carina slightly elevated. Malar space 0.55–0.6× as long as basal width of mandible. Mandible short, lower margin of mandible with wide flange from teeth toward base, mandibular teeth of equal length.

Mesosoma: Mesosoma with dense, whitish hairs. Pronotum with strong transverse striae; dorsal half granulose with weaker striae, ventral half smoother, shinier with stronger striae; epomia strong. Mesoscutum granulose and densely punctate, matte, 0.9× as long as wide; notaulus not developed. Scuto-scutellar groove wide and deep; scutellum granulose and punctate, matte, short, convex in profile, without lateral carina. Mesopleuron matte, coarsely granulose and more or less punctate, punctures stronger and more distinct on anterior and ventral parts; upper and middle parts of dorsal half of mesopleuron with strong transverse striae; speculum granulose, matte, without distinct punctures; mesopleural suture deep with strong, short transverse costae. Pleural part and ventral part (behind fore coxae) of prepectal carina (epicnemial carina) complete, narrow; transverse part (i.e. part at the level of sternaulus running through the epicnemium to the ventral edge of pronotum) absent; pleural part obliquely bent to anterior margin of mesopleuron reaching it below its middle height. Sternaulus indistinct. Posterior transverse carina of mesosternum complete. Metanotum short, granulose and punctate, matte. Metapleuron coarsely granulose, matte, punctures usually indistinct; coxal carina (juxtacoxal carina) anteriorly present, distinct but weak; submetapleural carina complete, strong. Pleural carina of propodeum strong; propodeal spiracle elliptic, separated from pleural carina by about its length. Propodeum coarsely granulose, propodeal carinae indistinct; area superomedia and area petiolaris rather deeply and widely impressed, centrally with strong transverse striae all along the impression.

Fore wing with short-stalked areolet, second recurrent vein (2 m-cu) distal to its middle; distal abscissa of Rs straight; nervulus (cu-a) postfurcal; postnervulus (abscissa of Cu 1 between 1 m-cu and Cu 1a + Cu 1b) intercepted slightly above middle by Cu 1a; lower external angle of discoidal cell (second discal cell) acute (ca 75°). Pterostigma long and narrow. Hind wing with nervellus (cu-a + abscissa of Cu 1 between M and cu-a) reclivous, not intercepted; discoidella (distal abscissa of Cu 1) spectral, proximally absent. Coxae finely granulate. Legs relatively slender, hind femur 4.2–4.5× as long as high. Inner spur of hind tibia 0.8–0.85× as long as metatarsus (first tarsomere of hind tarsus). Tarsal claws small and short but longer than arolium, with 2–3 strong basal pecten.

Metasoma: Metasoma very finely granulose with blunt greasy shine. Whitish hairs on metasoma sparser than on mesosoma, posterior two-thirds of middle and apical tergites, except hind edges, usually hairless. First tergite 1.2× as long as second tergite, and shorter than hind femur. Second tergite 1.4–1.5× as long as its apical width; thyridium oval, its distance from basal margin of tergite about 2× as long as its length. Third tergite 0.8–0.9× as long as its apical width; following tergites wider than long. Epipleurum of second and third tergites separated by a crease. Seventh tergite without apical excision. Ovipositor sheath as long as apical depth of metasoma; ovipositor strong, stout, dorsal preapical notch deep, ovipositor tip strongly narrowed, thin.

Colour: Antenna dark brown. Head black except yellow palpi and mandibles, mandibular teeth reddish brown. Mesosoma black except light yellow tegula. Metasoma black to very dark brown. Wings hyaline, wing veins and pterostigma brown. Fore leg: coxa black; trochanter yellow, basally brownish; trochantellus yellow; femur reddish; tibia reddish, externo-medially yellowish; tarsus yellowish, last tarsomere apically brown. Middle leg: coxa black; trochanter brownish, apically yellow; trochantellus yellow; femur brownish red; tibia reddish, externo-medially yellowish; tarsus yellowish, last tarsomere apically brown. Hind leg: coxa black; trochanter blackish; trochantellus yellow; femur blackish to dark brown; tibia subbasally and in apical third brown, basally and externo-medially ivory; tarsus brown, metatarsus basally ivory. Tibial spurs pale yellow to ivory. Claws reddish brown, pecten on claws brown.

Male: Unknown.

Distribution – Currently known only from Georgia.

Ecology – No host is known. Most probably, similar to other Casinaria species , the new species is a koinobiont endoparasitoid of lepidopterous hosts.

Etymology – The specific epithet onyx is derived from the Latin noun “onyx”, meaning the black onyx mineral, which resembles in colouration (predominantly black with few lighter, often creamy or ivory patches) to the colouration of the new species; noun in apposition, ending not to be changed.

Remarks on identification – By using the identification key of the most recent revision of Western Palaearctic Casinaria species ( RIEDEL 2018), C. onyx sp. n. keys out either at couplet 31 with C. stygia Tschek, 1871 and C. pallipes Brischke, 1880 , or at couplet 21 with C. hinzi Riedel, 2018 and C. dubia Tschek, 1871 , depending on the choice at couplet 1 (the new species is very close to the distinctive limit of couplet 1). The distinctive characteristics from C. pallipes Brischke, 1880 and from C. hinzi Riedel, 2018 are given in the Diagnosis section; the new species can be readily separated from C. dubia Tschek, 1871 by the relative length of ocellus diameter to ocular-ocellar distance, and from C. stygia Tschek, 1871 by the colouration of hind tibia.

Figures

Figs 1–3. Holotype specimen of Casinaria onyx sp. n., 1 = lateral habitus, 2 = head, frontal view, 3 = propodeum, dorsal view