Thyreodon delvarei, 2004

Gauld, Ian D. & Janzen, Daniel H., 2004, The systematics and biology of the Costa Rican species of parasitic wasps in the Thyreodon genus-group (Hymenoptera: Ichneumonidae), Zoological Journal of the Linnean Society 141 (3), pp. 297-351 : 331-332

14. THYREODON DELVAREI GAULD SP. NOV.

Fore wing length 18.8–20.5 mm; clypeus weakly convex, with apex flared outwards, bluntly pointed medially; malar space about 0.6 times basal mandibular width; maxillary palp long with second palpomere strongly broadened and slightly inflated; lower face centrally finely and sparsely punctate; frons weakly convex between antennal sockets and without a carina extending from outer rim of antennal sockets upwards, close to and parallel with eye margin; frons centrally smooth; ocelli moderately large, the lateral ocellus separated from eye by about 0.7 times its own maximum diameter; head in dorsal view with gena rather evenly rounded behind eye, occipital carina strong, its lower end sharp, not reaching hypostomal carina; antenna setaceous, with 50–52 flagellomeres, the 20th subquadrate, 1.0 times as long as broad, the subapical ones with setae which are longer than the diameter of the flagellomere. Pronotum short with anterior margin strongly and broadly reflexed, and with posterior margin centrally swollen, forming an angular, centrally impressed ridge which is separated from the anterior margin by a deep U-shaped groove; epomia possibly represented on upper part of pronotum by one of several rugae; propleuron smooth, almost impunctate, with lower corner rounded, peripherally not impressed; mesoscutum highly polished, very finely and sparsely punctate, with only a slight vestige of notauli; scuto-scutellar groove very deep, laterally margined by very strongly raised carinae; scutellum polished, finely and sparsely punctate, weakly convex; mesopleuron highly polished, almost impunctate, without a trace of a sternaular impression; metapleuron finely punctate; propodeum laterally weakly convex, with a sharp (and often rather smooth) low ridge above and behind the spiracle, rugose with the rugae tending to be parallel lower down; propodeum posterodorsally rugose-reticulate, with strong transverse rugae posterolaterally, centrally with a single shallow longitudinal impression. Fore leg of female rather stout, with coxa with a conspicuous bluntly rounded protuberance behind trochanteral insertion, with 5th tarsomere about 0.5 of length of preceding two tarsomeres, with tarsal claw moderately long and with moderately coarse, close pectinae; hind coxa in profile moderately large, its hind end extending well beyond hind end of propodeum; hind femur stout, about 4.5–5.0 times as long as maximally deep; hind tarsus of male with dense, moderately long pubescence ventrally. Fore wing with abscissa of Cu 1a between Cu 1b and 2 m-cu 0.9–1.0 times as long as abscissa of Cu 1 between cu-a and 1 m-cu. Metasoma with tergite I slender, anteriorly subcylindrical; tergite II, in lateral view, 2.3–2.5 times as long as posteriorly deep. Male with subgenital plate small and convex, covered with sparse coarse hair; claspers long, the dorsal apex elongately rounded/truncate, slightly inclined upwards without an apical spine-like projection, the lower margin weakly convex; aedeagus in profile with apex up-turned, very weakly flattened, with a sharp lateral keel.

A polished black species with mesopleuron and coxae with a blue-black metallic sheen; wings uniformly blackish infumate.

Remarks: Thyreodon delvarei is named in honour of Gerard Delvare, in recognition of his enthusiastic identification of the thousands of chalcidid wasps reared by the ACG caterpillar inventory. T. delvarei rather closely resembles T. darlingi in general appearance and coloration. Both are shining black species with uniformly black wings and a slightly metallic sheen to the mesosoma, both have rather large ocelli, and the males of both species have a long, slightly bent clasper that lacks an apical spine and has the apex of the aedeagus somewhat flattened. T. delvarei differs from T. darlingi in having slightly smaller ocelli that are separated from the eye margin by about 0.7 of their own maximum diameter, whereas those of T. darlingi are separated by about 0.2 of their maximum diameter. The malar space of T. delvarei is wider than T. darlingi , it lacks the strongly impressed notauli and it has the mesopleuron much smoother and less sculptured.

Biological notes: Although Thyreodon delvarei occurs well within the area of the ACG caterpillar rearing programme, it has not yet been encountered in many thousands of caterpillars and many tens of species of sphingids reared from these mid- to upper-elevation rain forest sites.

Material examined: Holotype ♀, COSTA RICA, Guanacaste Prov., Rincon de la Vieja National Park, Estacion Las Pailas, 800 m, vi.1992 ( Garcia ) ( INBio ). Paratypes: COSTA RICA: Guanacaste Prov.: 1 ♀, Guanacaste National Park, Estacion Cacao, 1000–1400 m, vi.1990 (Parataxonomists) ( INBio ): Puntarenas Prov.: 1 ♂, Monteverde, Finca Buen Amigo, 4 km S of Reserve, 1000–1350 m, v.1997 ( Fuentes ) ( INBio ).