Orthocentrus alboscutellum Broad

Veijalainen, Anu, Broad, Gavin R. & Sääksjärvi, Ilari E., 2014, Twenty seven new species of Orthocentrus (Hymenoptera: Ichneumonidae; Orthocentrinae) with a key to the Neotropical species of the genus, Zootaxa 3768 (3), pp. 201-252 : 230-231

Orthocentrus alboscutellum Broad , sp. nov.

Figs 5 A, 6 M, 10 A, 11 M, 14 J.

Fore wing length 4.0– 4.3 mm.

Face medially 1.2x wider than high; face smooth and polished, upper half horizontally lightly strigose across entire width, 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, antennal sockets not on a distinct high shelf; malar groove straight; maxillary palp very long, reaching back to mid coxae. In dorsal view, head posteriorly moderately concave, temples distinct, posterior ocelli distant from eye by 1.0x ocellar diameter, anterior ocellus separated from eye by 1.4x ocellar diameter, ocellar-ocular grooves faintly present. Minimum distance between antennal sockets slightly less than the diameter of socket; antenna about as long as body, slender, with 32 thin, elongate flagellomeres which gradually shorten towards apex of antenna; basal flagellomere 0.2x as wide as high and about same length as scape; scape curved, in frontal view concave on lateral surface, convex on inner surface.

Mesosoma smooth, polished, impuncate, some microsculpture on propodeum; mesoscutum lacking notauli; in profile, scutellum not particularly high, slightly convex, metapleuron slightly convex; propodeum with posterior transverse carina strong and raised, present between lateral longitudinal carinae, median longitudinal carinae complete, not strong, lateral longitudinal carinae present posterior to spiracles, spiracles large.

Legs stout, hind leg massive; coxae and femora polished, tibiae and tarsi coriaceous-granulate; hind coxa 1.1x as long as first tergite, hind femur 3.1x as long as maximum depth, hind tibia 4.5x as long as apical width; tibiae with scattered spine-like setae.

Wings not particularly narrow; fore wing with areolet open, vein Rs straight; hind wing with vein cu-a not intercepted, straight.

First tergite somewhat elongate and apically slightly widening, 1.6x as long as apically wide; heavily rugosestrigose, with two complete median longitudinal carinae detectable amongst sculpture, with transverse impressions originating at about middle of tergite, sloping posteriorly, not meeting centrally. Second tergite 1.1x as long as apically wide; heavily rugose-strigose, with slight transverse impressions originating at about middle of tergite, sloping anteriorly and posteriorly, not meeting centrally, forming a somewhat oval or diamond-shaped horizontal uplifted median area; second thyridia present as raised, black ovals. Third tergite with rugose-strigosity reaching apical 2/3 of tergite, sculpture towards posterior edge smoother and punctate, with slight transverse impressions originating at about middle of tergite, sloping anteriorly, not meeting centrally; thyridia contrastingly coloured, basal thyridia large, narrow, oval/rectangular, second thyridia small circular. Apical tergites smooth, fourth tergite sometimes narrowly and slightly strigose basally. Ovipositor thin, straight, without notch; ovipositor sheath sharply truncate at sharp angle ventrally, with rather dense, backwards-directed curved setae

Setae over whole body (including metasoma) except eyes, pronotum, mesopleuron, metapleuron, scattered on propodeum and posterior sides of coxae.

Flagellomeres dark brown; laterally, mesosoma mostly creamy white; face and vertex to half eye height creamy, frons, dorsal vertex brown, pronotum creamy ventrally, brown dorsally, mesopleuron creamy, brown in antero-dorsal corner, metapleuron creamy; mesoscutum dark brown anteriorly and narrowly or widely laterally, centrally dark yellow, scutellum white, propodeum dark brown; legs basically creamy white, brown on ventral sides of femora, outer sides of fore and mid tibia, ventral area of hind coxa, hind trochantellus, ill-defined area on hind trochanter, broad basal and apical bands on hind tibia. Tarsi all pale brown, hind tarsus paler basally. Tergites and hypopygium (except medio-basally) dark brown. Sternites white with light brown more sclerotized patches.

Male. Unknown.

Biology. Hosts unknown. Only two specimens have been found, collected in dense primary forest at midelevation in Costa Rica.

Etymology. Named after the white scutellum.

Comments. Morphologically very similar to O. broadi but differing distinctly in colour pattern; this is a smaller species with a slenderer metasoma, more rugose and punctate elements to the strong metasomal sculpture, and the back of the head is more concave.

Material examined. Holotype female: ‘ Costa Rica: Ptas [Puntarenas] Pv. San Vito, Las Alturas 1500m VII.1991 K. Gaston’ ( BMNH).

Paratype female: same data as holotype except IX–XI.1992 ( BMNH).

Figures

FIGURE 5. Lateral views: Orthocentrus insularis (excluding O. albihumerus which is very similar to O. breivipilus; see descriptions) and O. zebra species-groups. A: alboscutellum, B: onkonegare, C: brevipilus, D: broadi, E: zebra, F: insularis. Scale 1.0 mm.