Orthocentrus longiventris, Humala, 2019

Humala, Andrei E., 2019, Mexican species of the genus Orthocentrus (Hymenoptera, Ichneumonidae: Orthocentrinae), Zootaxa 4709 (1), pp. 1-83 : 71-72

Orthocentrus longiventris sp. nov.

( Figs 6 D , 11 D , 14 M , 17 M , 24 )

Material examined. Holotype ♀: México, Oaxaca, Santiago, Comaltepec , 2427 m, N 17.58424°, W 96.49428°; humid oak pine forest, MT, 12–20.VI.2007, leg. H. Clebsch ( UNAM).

Paratypes: 1 ♀ Tlaxcala, Nanacamilpa; San Felipe Hidalgo, Ejido Los Búfalos , N 19°27′35.2″, W 98°35′46.9″, 2831 m, 1–26.VIII.2016, leg. A. Contreras & Y. Marquez ( UNAM) ; 1 ♀ Hidalgo, Huasca de Ocampo , rancho Sta. Elena, MT3, 25.XI–26.XII.2005, leg. A. Contreras et al.; Hidalgo, Huasca de Ocampo , rancho Sta. Elena, 2480 m, MT, 25.I–23.II.2006, leg. Meléndez ( UNAM and ZISP) .

Description. Female. Body length 5.8 mm, fore wing length 3.4 mm.

Face medially 1.1 × wider than high; face fairly sparsely punctate, shining, eyes not setose, dorsal ridge of face inbetween antennal sockets without a median prominence; face profile almost straight, edge of clypeus slightly impressed, margin straight; head clearly transverse, antennal sockets not on a distinct high shelf (Hw/Fp = 6.5); subocular sulcus distinct, slightly bent towards occiput; maxillary palp reaching to about epicnemial carina. In dorsal view, head posteriorly slightly concave, temples distinct, about 0.25 × eye width, posterior ocelli distant from eye by 1.4 × ocellar diameter, anterior ocellus separated from eye by 2.5 × ocellar diameter, ocellar-ocular grooves present. Minimum distance between antennal sockets about or slightly less than the diameter of socket; antenna slender, with 27–29 (n=3) elongate flagellomeres which gradually slightly shortening towards apex of antenna; basal flagellomere 2.8 × as long as wide and about 2/3 as scape; scape curved, in frontal view slightly concave on lateral surface, convex on inner surface.

Mesosoma smooth, polished; mesoscutum lacking notauli, propodeum with some microsculpture; in profile, scutellum high and convex, metapleuron slightly convex; propodeum with carinae weak, posterior transverse carina present between lateral longitudinal carinae, median longitudinal carinae complete, slightly convergent apically; lateral longitudinal carinae present posterior to spiracles, spiracles medium-sized.

Legs moderately stout, hind leg massive; coxae and femora polished, tibiae and tarsi coriaceous-granulate; hind coxa 1.0 × as long as first tergite, hind femur 3.3 × as long as maximum depth, hind tibia 4.3 × as long as apical width; tibiae with scattered spine-like setae; hind claws enlarged.

Wings not particularly narrow; fore wing with areolet closed, wide, pentagonal, second recurrent vein (2m-cu) meeting areolet at apical 0.7; vein Rs straight; nervulus oblique, slightly postfurcal; hind wing with nervellus intercepted below.

First tergite somewhat elongate and almost parallel-sided, 2.1 × as long as apically wide; finely rugose, without distinct median longitudinal carinae, with transverse impressions originating at about apical third of tergite, sloping posteriorly, meeting centrally. Second tergite 1.7 × as long as apically wide; rugose, with anterolateral diagonal impressions connected with more shallow angular posterior transverse groove, forming a somewhat oval or diamondshaped horizontal uplifted median area; second thyridia present as raised, reddish-brown ovals inside this area. Third tergite coriaceous basally, sculpture towards posterior edge smoother, basal thyridia large, narrow, oval/rectangular, contrastingly coloured, second thyridia small oval. Fourth tergite polished with basal thyridia large, narrow, oval/rectangular, contrastingly coloured. Apical tergites smooth and polished. Ovipositor thin, slightly upcurved, without subapical dorsal notch; ovipositor sheath pointed, with rather long, backwards-directed curved setae.

Body largely setose except eyes, pronotum, mesopleuron, metapleuron, scattered on propodeum and posterior sides of coxae and femora.

Dark brown, except face, clypeus, malar space, antenna ventrally, propleuron ventrally, pronotum ventrally and dorso-posteriorly, fore and mid legs except coxae and trochanters, basal thyridia and apical margins of first, second and third tergites light brown; mouthparts, except fuscous apical palpomeres, inner orbits, tegula, fore and mid coxa, trochanter and trochantellus, hind tibia basally, hind basitarsus basally and sternites creamy.

Male. Unknown.

Biology. Hosts unknown. The specimens have been collected at high-elevation sites.

Distribution. Mexico (Hidalgo, Oaxaca, Tlaxcala).

Etymology. Named after the long metasoma.

Comments. Compared with the other species that have completely papillate face, antennal sockets on a distinct but low shelf, and glabrous eyes, pterostigma nearly symmetrical and basal flagellomere 2.8 × as long as wide, unlike in O. flavoorbitalis and O. rhombifer ; frontal orbits and mesoscutum fuscous, unlike in O. hidalgoensis and O. ungularis ; hind legs fuscous and first tergite 2.1 × as long as posteriorly wide, unlike in O. elongatus .

Figures

FIGURE 6. Lateral views: Orthocentrus ungularis species-group. A: elongatus, B: flavoorbitalis, C: hidalgoensis, D: longiventris, E: rhombifer, F: ungularis. Scale 1.0 mm.

FIGURE 11. Faces: Orthocentrus ungularis species-group.A: elongatus, B: flavoorbitalis, C: hidalgoensis, D: longiventris, E: rhombifer, F: ungularis. Scale 0.2 mm.

FIGURE 14. Heads in dorsal view: Orthocentrus maculae and O. ungularis species-groups. A: brevicornis, B: coronadoae, C: latus, D: lopezi, E: rufipleuris, F: scutellatus, G: similis, H: tergalis, I: varicolor, J: elongatus, K: flavoorbitalis, L: hidalgoensis, M: longiventris, N: rhombifer, O: ungularis. Scale 0.2 mm.

FIGURE 17. Basal tergites: Orthocentrus maculae and O. ungularis species-groups. A: brevicornis, B: coronadoae, C: latus, D: lopezi, E: rufipleuris, F: scutellatus, G: similis, H: tergalis, I: varicolor, J: elongatus, K: flavoorbitalis, L: hidalgoensis, M: longiventris, N: rhombifer, O: ungularis. Scale 0.2 mm.

FIGURE 24. Distribution map of Orthocentrus in Mexico. O. elongatus, O. flavoorbitalis, O. longiventris, O. rhombifer