Orthocentrus orientalis Humala & Lee, 2020

Humala, Andrei E., Lee, Jong-Wook & Choi, Jin-Kyung, 2020, A review of the genus Orthocentrus Gravenhorst (Hymenoptera, Ichneumonidae, Orthocentrinae) from South Korea, Journal of Hymenoptera Research 75, pp. 15-65 : 15

13. Orthocentrus orientalis Humala & Lee sp. nov.

Fig. 10

Description.

Female. Fore wing length 2.4-2.8 mm.

Face at level of antennal sockets 1.1 times as wide as high; face smooth and densely punctate, eyes not setose, dorsal ridge of face in between antennal sockets without a median prominence; face profile straight, slightly impressed dorsally, edge of clypeus straight, antennal sockets on a shelf; inner orbits subparallel; subocular sulcus distinct, nearly straight; maxillary palp long, reaching beyond to fore coxa. In dorsal view, head posteriorly concave, temples short, lateral ocellus distant from eye by a distance 1.5 times longer than its maximum diameter, POL 1.6 times as long as diameter of lateral ocellus. Minimum distance between antennal sockets about 0.6 × of the socket diameter; antenna with 22-24 flagellomeres (n = 10) which gradually shorten towards apex; first flagellomere 2.3-2.5 times as long as wide and 0.6 times as long as scape; scape nearly parallel-sided.

Mesosoma smooth and polished except pronotum with short striations postero-ventrally, propodeum with alutaceous-coriaceous microsculpture; mesoscutum with notauli anteriorly indicated; in profile, scutellum weakly convex, metapleuron slightly convex; propodeum with posterior transverse carina between lateral longitudinal carinae, lateromedian longitudinal carinae complete, lateral longitudinal carinae weak but present posteriorly, spiracle small.

Legs slightly flattened; coxae and femora polished, tibiae and tarsi coriaceous; hind femur 2.8 times as long as high, hind tibia 4.0 times as long as apically wide; tibiae with spine-like setae, spurs of hind tibia distinctly curved apically.

Wings not particularly narrow, fore wing with areolet closed, slightly transverse, narrowly sessile, vein 3rs-m weak; 2m-cu meeting areolet at apical 0.7, vein Rs gently bent towards wing apex; vein cu-a distad of Rs&M; nervellus angled below the middle.

Metasoma slender and considerably compressed from tergite 3 to apex. First tergite elongate, slightly widening posteriorly, 2.1 times as long as posteriorly wide; coriaceous-strigose, lateromedian longitudinal carinae weak and indistinct, with shallow transverse impressions originating at about middle of tergite, sloping posteriorly, not meeting centrally. Second tergite parallel-sided, 1.8 times as long as posteriorly wide; coriaceous and finely strigose, with shallow transverse impressions originating at about middle of tergite, sloping posteriorly, polished apically; small thyridia oval. Third tergite elongate, nearly 2.0 times as long as posteriorly wide, coriaceous medio-basally, polished in posterior half. Remaining tergites unsculptured. Ovipositor thin, slightly upcurved, without dorsal notch, pointed apically; ovipositor sheath narrow, parallel-sided, with dense setae longer than sheath width and curved backwards.

Body largely setose except eyes, pronotum, mesopleuron and metapleuron; setae scattered on anterior tergites and posterior sides of coxae.

Dark brown except face, clypeus, malar space, antennae, hind legs yellowish brown; mouthparts, tegula, propleuron, hind corners of pronotum, fore and mid legs yellowish; metasoma from tergite 4 brown; sternites creamy; sometimes lower inner orbits with blurred reddish-brown marks.

Male. Unknown.

Biology.

Hosts unknown.

Etymology.

This species is named from the Latin Orthocentrus orientalis (eastern) after its geographical distribution, as the Korean Peninsula is situated in the Far East.

Comparison.

Compared with the other species that have antennae on a shelf, it has a granulate face and no distinct yellow marks along the inner orbits, the first flagellomere 2.3-2.5 times as long as wide, the areolet comparatively small, the first tergite 2.1 times as long as posteriorly wide, the second tergite 1.8 times as long as posteriorly wide. Additionally, the subocular sulcus is nearly straight, the POL 1.6 times as long as the diameter of a lateral ocellus, and the fore wing length is 2.4-2.8 mm (unlike in O. parvus ).

Material examined.

Holotype: female; South Korea GG: Mt. Yongmunsan Yeonsu , Yongmun, Yangpyeong, 320 m, MT III, 26.VI-16.VII.2009, J.O. Lim leg. (DNUE-0309).

Paratypes: South Korea, GB: 2♀, Mungyeong-si , Gaeun-eup , Wanjang-ri , Mt. Songnisan National Park , Beorimigijae , 36°40'59"N, 127°57'07"E, MT, 17.VII-12.VIII.2013, J.K. Choi leg. (DNUEU-0075, ZIN-0079); GN: 1♀, Dapcheon-ri, Ibanseong-myeon, Jinju-si, MT III, 27.VI-4.VII.2005, B.K. Ahn leg. (DNUE-0302); GG: 1♀, Mt. Yongmunsan Yeonsu, Yongmun, Yangpyeong, 324 m, MT III, 26.VI-16.VII.2009, J.O. Lim leg. (DNUE-0307); GW: 1♀, Chuncheon-si Dong-myeon Jinae-ri, 1-10.VII.2005, S.J. Jang leg., S.N. U. (DNUE-0387); 2♀, Wonju-si, Heungeop-myeon, Yeonse University, MT, 22.VII-11.VIII.2007, J.W. Lee leg. (DNUE-0152, 0035); JB: 2♀, Jeongeup-si, Naejang-dong Naejang-san, Geumseongyegok (14 site), MT, 29.VI-6.VII.2008, J.W. Lee leg. (DNUE-0313, 0315); JN: 1♀, Kwangju-si, Buk-gu, Geumgok-dong, Mudeungsan Nat. park Wonhyosa, MT, 26.VI-27.VII.2013, J.K. Choi leg. (DNUE-0141) ;

Distribution.

South Korea (GB, GN, GG, GW, JB, JN).

Figures

Figure 10. Orthocentrus orientalis sp. nov. Holotype. A Habitus in lateral view B head in frontal view C head in dorsal view D head and mesosoma in lateral view E mesosoma in dorsal view F areolet G first to third tergites in dorsal view.