Orthocentrus similis, Humala, 2019

Humala, Andrei E., 2019, Mexican species of the genus Orthocentrus (Hymenoptera, Ichneumonidae: Orthocentrinae), Zootaxa 4709 (1), pp. 1-83 : 31-32

Orthocentrus similis sp. nov.

( Figs 5 D , 10 J , 14 G , 17 G , 26 )

Material examined. Holotype ♀: México, Oaxaca, Municipio S. Comaltepec, La Esperanza , 1600 m, N 17.62661°, W 96.36950°, MT, 10–20.VI.2008, leg. A. Lopez ( UNAM).

Paratypes: 2 ♀ Veracruz, Est. Biol. Trop. Los Tuxtlas, C 6, MT-II, 155 m, N 18°35′07.6″, W 95°04′47.5″, no date, leg. M. Madora ( UNAM) ; 2♀ C7, MT-II, Pte- Aula- Lab. EBTLT 17.IX–15.X.2013, leg. M. Madora ( UNAM, ZISP) ; 1 ♀ C4, MT-II, Pte- Aula- Lab. EBTLT 16.VI–24.VII.2013, leg. M. Madora ( UNAM) .

Description. Female. Fore wing length 3.4 mm.

Face medially 1.1 × as wide as high; smooth and polished, with shallow, sparse punctures, eyes not setose, dorsal ridge of face inbetween antennal sockets without a median prominence; orbits strongly divergent ventrally; face profile slightly rounded, edge of clypeus straight, slightly impressed, antennal sockets not on a distinct high shelf (Hw/Fp = 8.1); subocular sulcus distinct, sharp, slightly bent towards occiput; maxillary palp reaching slightly beyond fore coxa. In dorsal view, head posteriorly slightly concave, temples narrow, but distinct, about 0.25 × eye width, hind ocellus separated from eye by 0.9 × ocellar diameter, anterior ocellus separated from eye by 1.9 × ocellar diameter, lacking ocellar-ocular grooves. Minimum distance between antennal sockets slightly more than half diameter of socket; antenna slender, with 23 flagellomeres elongate, which gradually slightly shortening towards apex of antenna; basal flagellomere 2.1 × as long as wide and about 0.4 × of the length of scape; scape with internal surface convex, outer side concave.

Mesosoma polished except for pronotum with short striate postero-ventrally; sometimes with vague, coria- ceous microsculpture dorsally on propodeum; mesoscutum without notauli; in profile, scutellum high, metapleuron strongly convex; propodeum with posterior transverse carina complete, strong, raised as distinct projections at level of lateral longitudinal carinae; median longitudinal carinae complete, lateral longitudinal carinae present as stubs not reaching spiracles, spiracles medium-sized.

Legs broad; coxae and femora polished, femora with inconspicuous alutaceous-coriaceous sculpture, tibiae and tarsi coriaceous-granulate; hind coxa 1.1 × as long as first tergite, hind femur 3.1 × as long as high, hind tibia 4.2 × as long as apically wide; tibiae with spine-like setae.

Wings not particularly narrow; fore wing with areolet open, vein Rs somewhat sinuous; hind wing with nervellus straight, not intercepted.

First tergite elongate, 1.4 × as long as apically wide, in dorsal view, slightly wider at spiracles; sometimes with small basolateral teeth; coriaceous, with complete median longitudinal carinae, with transverse impressions originating at about middle of tergite, sloping posteriorly, not meeting centrally. Second tergite 0.95 × as long as apically wide; coriaceous, with longitudinal striae, median longitudinal carinae of first tergite continuing onto base of second tergite, with diagonal-transverse impressions originating at about middle of tergite, sloping anteriorly and posteriorly, not meeting centrally, forming a somewhat oval or diamond-shaped horizontal uplifted area in the middle; thyridia absent. Remainder of metasoma impunctate, without thyridia. Ovipositor rather strong, upcurving, with well-defined notch; ovipositor sheath pointed, with sparse, long, curved, backwards-directed setae.

Body setose except eyes, pronotum, mesopleuron and metapleuron, setae scattered on metasoma and posterior coxae.

Dark to blackish brown except inner orbits from antennal sockets to ocelli creamy to light yellow, mouthparts, malar area behind subocular sulcus, sternites and fore and mid coxae, trochanters, trochantelli white to creamy; face yellow; propleuron, pronotum ventrally, mesopleuron in ventral half, apical margin of second tergite and legs largely orange except apex of hind coxa and hind femur, dorsal surface of hind tibia and hind tarsus distinctly brown; mesoscutum sometimes brownish.

Male. Unknown.

Biology. Hosts unknown. Material collected from cloud forests and lower elevation sites.

Distribution. Mexico (Oaxaca, Veracruz).

Etymology. Named after its high similarity with O. rufipleuris .

Comments. Compared with the other species from O. maculae species-group, where this species undoubtedly belongs, the notauli not developed. Most similar to O. rufipleuris but differs in bent subocular sulcus, shorter basal flagellomere, clypeus truncate, nervellus not intercepted, blackish brown mesoscutum, and in some details of the colour pattern; from similar O. similis and O. varicolor differs in bent subocular sulcus, absence of a median prominence on dorsal ridge of face inbetween antennal sockets, and orange ventral half of mesopleuron.

Figures

FIGURE 5. Lateral views: Orthocentrus maculae species-group.A: lopezi, B: rufipleuris, C: scutellatus, D: similis, E: tergalis, F: varicolor. Scale 1.0 mm.

FIGURE 10. Faces: Orthocentrus montanus (in part) and O. maculae species-groups. A: montezuma, B: sierrae, C: tlaxcalensis, D: brevicornis, E: coronadoae, F: latus, G: lopezi, H: rufipleuris, I: scutellatus, J: similis, K: tergalis, L: varicolor. 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 26. Distribution map of Orthocentrus in Mexico. O. latus, O. luteoclypeus, O. rufipleuris, O. similis