Orthocentrus mexicanus, Humala, 2019

Humala, Andrei E., 2019, Mexican species of the genus Orthocentrus (Hymenoptera, Ichneumonidae: Orthocentrinae), Zootaxa 4709 (1), pp. 1-83 : 47-48

Orthocentrus mexicanus sp. nov.

( Figs 7 D , 12 D , 15 D , 18 D , 28 )

Material examined. Holotype ♀: México, Tamaulipas, Gómez Farias; Los Cedros , MT, 16–19.XII.1998, leg. S. Hernández & C. Covarrubias ( UAT).

Paratypes: 22 ♀ and 32 ♂ same data as for holotype, but the dates 28.XI–10.XII.1998, 19–26.XII.1998, 26.XII.1998 – 7.I.1999, 7–16.I.1999, 16–23.I.1999, 23–30.I.1999, 27.II–20.III.1999, leg. S. Hernández & C. Covarrubias; Tamaulipas, Gómez Farias, Los Cedros 16. XII.1998, leg. D. Kasparyan; Tamaulipas, Gómez Farias, Alta Cima, MT , 27.III–3.IV.1999, leg. S. Hernández ( UAT) ; Oaxaca, Municipio S. Comaltepec , La Esperanza, 1600 m, N 17.62661°, W 96.36950°, MT, 10-20.VI.2008, leg. A. Lopez ( UNAM) ; 1 ♂ Morelos, Cuernavaca , University botanical garden , 1900 m, 2.III.2010, leg. A. E. Humala; Veracruz, Jalapa, park near Institute de Ecologia , 1260 m, N 19°30.768′, W 96°56.349′, 17–18.II.2009, leg. A.I. Khalaim; Yucatán, Corral ( SMSC) , Sudzal Chico ( SMSP) , XI–1999, leg. Hugo Delfín ( UAT, UNAM, ZISP, KRC) .

Description. Female. Fore wing length 3.0– 3.5 mm.

Face medially 0.9 × as wide as high; face rather coarsely papillate, eyes setose, dorsal ridge of face inbetween antennal sockets without a median prominence; inner orbits slightly divergent ventrally; face profile evenly rounded, antennal sockets on a moderately high shelf (Hw/Fp = 4.5); edge of clypeus slightly rounded; subocular sulcus distinct, sharp, slightly bent towards occiput; maxillary palp reaching beyond fore coxa. In dorsal view, head posteriorly moderately concave, temples distinct, about 0.25 × eye width; frons and vertex sparsely punctate, hind ocellus separated from eye by c. 1.0 × ocellar diameter, anterior ocellus separated from eye by c. 2.0 × ocellar diameter, lacking ocellar-ocular grooves. Minimum distance between antennal sockets about 0.4 × diameter of socket. Antenna with 24–26 rather stout flagellomeres, which not gradually shortening towards apex of antenna; basal flagellomere 1.2–1.3 × as long as wide and about half of length of scape; the rest flagellar segments slightly longer their width or quadrate; scape in frontal view straight on lateral surface, slightly convex on inner surface.

Mesosoma largely smooth and polished except for some small striae on postero-ventral corner of pronotum and coriaceous microsculpture on propodeum; mesoscutum sparsely punctate, with notauli anteriorly; in profile, scutellum somewhat high, metapleuron slightly convex; propodeum with posterior transverse carina complete, strong and raised between lateral longitudinal carinae, median longitudinal carinae complete, somewhat convergent apically, anterior portions of lateral longitudinal carinae obsolescent; spiracles medium-sized.

Legs somewhat stout; coxae polished, femora with inconspicuous coriaceous sculpture, tibiae and tarsi coriaceous-granulate; hind coxa 1.0–1.1 × as long as first tergite, hind femur 2.8–3.0 × as long as high, hind tibia 3.9 × as long as apically wide; tibiae with spine-like setae; arolium longer than hind claws.

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

First tergite slightly widening apically, 1.3–1.4 × as long as apically wide; coriaceous, strigose apically, with complete or posteriorly almost complete median longitudinal carinae, with transverse impressions originating at about middle of tergite, sloping posteriorly, not meeting centrally. Second tergite 0.8–0.9 × as long as apically wide; coriaceous, with longitudinal striae, shallow transverse groove near apical margin bending anteriorly near lateral margins; basal thyridia quadrate-elongate, contrastingly coloured, second thyridia round, same colour as surrounding cuticle. Third tergite coriaceous basally, polished apically; second thyridia small, round. Remain- der of metasoma impunctate, nearly polished. Ovipositor straight, without dorsal notch; ovipositor sheath with sparse, long, backwards-directed setae.

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

Dark to blackish brown except antenna with yellow proximally, ventrally, clypeus yellow to orange, mouthparts, malar space, top of face between antennal sockets, spot on frontal orbit at level of antennal sockets, tegula, pronotum dorso-posteriorly and sternites creamy; fore and mid legs yellow with creamy trochanter and trochantellus; hind coxa dark brown, coxa apically, trochanter, trochantellus, femur basally yellowish, hind tibia and tarsus yellowish, dark apically; tergites of metasoma uniformly dark-brown.

Male. Antennae with 20–22 flagellomeres, basal flagellomere 4.0 × as long as wide. Eyes glabrous. Fuscous. Face, clypeus, malar space, palpi, mandibles, scapi ventrally, inner frontal orbits in lower part, small spots in the dorso-posterior corners of pronotum and subalar prominence creamy. Other characters as in female.

Biology. Hosts unknown. Nothing is known of the biology of this species.

Distribution. Mexico (Morelos, Tamaulipas, Oaxaca, Veracruz, Yucatan).

Etymology. Named after the type locality, Mexico.

Comments. Compared with the other species that have a completely papillate face, antennal sockets on a distinct but low shelf, and areolet open, frontal orbits fuscous, unlike in O. oaxacae ; head and mesoscutum coarsely punctate, nervellus not intercepted, vein 2rm-s as long as second portion of cubitus, frontal orbits with yellow spots at level of antennal sockets, eyes with short setae, unlike in O. tamaulipecus . Similar to O. aztecus but differs in areolet open, first tergite with distinct median longitudinal carinae, hind femur light brown, hind tibia stouter.

Figures

FIGURE 7. Lateral views: Orthocentrus wahlbergi species-group (in part).A: aztecus, B: collaris, C: contrerasi, D: mexicanus, E: minor, F: oaxacae. Scale 1.0 mm.

FIGURE 12. Faces: Orthocentrus wahlbergi and O. insularis species-groups. A: aztecus, B: collaris, C: contrerasi, D: mexicanus, E: minor, F: oaxacae, G: pictus, H: podagricus, I: scabrosus, J: tamaulipecus, K: veracruzus, L: ruizi. Scale 0.2 mm.

FIGURE 15. Heads in dorsal view: Orthocentrus wahlbergi and O. insularis species-groups. A: aztecus, B: collaris, C: contrerasi, D: mexicanus, E: minor, F: oaxacae, G: pictus, H: podagricus, I: scabrosus, J: tamaulipecus, K: veracruzus, L: ruizi. Scale 0.2 mm.

FIGURE 18. Basal tergites: Orthocentrus wahlbergi and O. insularis species-groups. A: aztecus, B: collaris, C: contrerasi, D: mexicanus, E: minor, F: oaxacae, G: pictus, H: podagricus, I: scabrosus, J: tamaulipecus, K: veracruzus, L: ruizi. Scale 0.2 mm. Metasoma dorso-lateral view: M: Orthocentrus tergalis. Scale 0.5 mm.

FIGURE 28. Distribution map of Orthocentrus in Mexico. O. asper, O. aztecus, O. contrerasi, O. mexicanus