Physotarsus adriani Gauld, 1997

Zhaurova, Kira & Wharton, Robert, 2009, A revision of Physotarsus Townes (Hymenoptera: Ichneumonidae: Ctenopelmatinae), with description of 18 new species, Zootaxa 2207, pp. 1-52 : 10-12

Physotarsus adriani Gauld, 1997 ( Figs 9, 10 )

Physotarsus adriani Gauld, 1997: 194 –195. Holotype Ψ in INBio. Physotarsus adriani: Yu & Horstmann 1997: 455 (catalog).

Diagnosis. Lateral ocelli separated by 0.4–0.6X their widest diameter from each other and about 1.8–2.1X their widest diameter from eye margin. Antenna with 30–32 flagellomeres. Pronotum and mesoscutum glabrous, impunctate. T1 about twice as long as broad. Head brownish orange, face mostly brown. Mesosoma and metasoma orange. Hind legs orange, tarsomeres distally infuscate. Fore wing very strongly yellowish proximally, blackish infumate distally.

Physotarsus adriani is readily recognized by the distinctive color pattern of the fore wing, matched only in P. castilloi . The two are distinguished by color differences noted in the key above and in Gauld (1997), and in the shape of the ventral margin of the clypeus which is not as strongly protruding in P. adriani .

Description. Female: Body ( Fig. 9 ) 4.8–6.2 mm, fore wing 4.6–7.0 mm. Head ( Fig. 10 ): Clypeal margin widely truncate laterally, with thick, somewhat angulate central lobe. Clypeus flattened medially, about 3.6x as wide as long, divided medially by shallow transverse depression. Face covered with short setae; setae longer, less dense on clypeus. Anterior tentorial pits elongate and upcurved laterally. Malar space 0.4–0.5X width of mandibular base. Face 1.3X as broad as long, weakly bulging dorsomedially, evenly sparsely punctate. Interantennal area flat, area immediately behind antennae weakly concave laterally, turning convex before reaching ocelli. Anterior margin of torulus situated at about 0.7 of eye height. Interantennal distance greater than distance between lateral ocelli. Widest diameter of torulus 1.3x widest diameter of median ocellus. Lateral ocelli separated by 0.4–0.6X their widest diameter from each other and about 1.8–2.1X their widest diameter from eye margin. Area between lateral ocelli flat, area behind ocelli sharply declivitous. Antenna with 30-32 flagellomeres, first flagellomere 3.6–4.2X longer than wide, 1.4X widest transverse diameter of eye, second flagellomere 0.7–0.8X length of first. Occipital carina present on ventral 0.2–0.3 of head. Mesosoma: Anterior margin of pronotum medially slightly emarginate, laterally rounded and upcurved. Lateral groove of pronotum vestigial, present on dorsal 0.1, sometimes absent entirely. Pronotum and mesoscutum glabrous, impunctate. Epicnemial carina parallels anterior margin of mesopleuron. Mesopleuron impunctate, sparsely pubescent ventrally. Metapleuron pubescent, more sparsely so posteromedially. Propodeum without carinae; impunctate medially, pubescent anterolaterally. Tarsal claws simple. Fore wing stigma narrow, about 4.2X longer than wide; Rs+2r arising from basal 0.3–0.4 of stigma; marginal cell about 2.6–2.9X longer than wide; 2rs-m usually 1.6–1.7X (1.3x in one specimen) longer than abscissa of M between 2rs-m and 2m-cu; Cu1a about 0.5–0.7X length of 2cu-a; cu-a interstitital to weakly antefurcal relative to Rs&M. Hind wing M+Cu strongly bowed; basal abscissa of Rs 1.0–1.2X length of rs-m; 1st abscissa of Cu1 about 3.0–4.0X longer than cu-a. Metasoma: T1 about 2.0X as long as broad; surface in profile flat basally, weakly convex posteriorly, dorsal tendon anchored within small, relatively discrete depression; spiracles protruding in profile; dorsolateral carina extending about half distance to spiracle. Cerci distinct, round to slightly ovate, nearly flat.

Male: Similar to female in structure and color; subgenital plate with very broad U-shaped incision in posterior margin.

Color. Head brownish orange, face mostly brown. Antenna black. Mesosoma and metasoma orange, ventrally grading to yellowish. Fore and mid legs yellowish; hind legs orange, with tarsomeres distally infuscate. Fore wing very strongly yellowish proximally, blackish infumate distally; stigma usually pale orange-brown, rarely blackish.

Material Examined. Paratypes: 6 Ψ 1 ɗ COSTA RICA: Guanacaste Prov., Santa Rosa National Park, 300 m, 13.vi.1976 & 10.vi–1.vii.1977 (Janzen) ( AEIC); 3 Ψ Guanacaste National Park, Finca Jenny, vi.1990 ( INBio).

Remarks. Gauld (1997) noted that this was the most frequently collected species of Physotarsus in Costa Rica, though it was only found in the seasonal dry forests of northwestern Guanacaste. Specimens were collected only in June and July, shortly after the start of the wet season, but one sample of parasitized host larvae was collected in late May from new foliage ( Janzen 2006, Voucher code: 88-SRNP-67). Following cocoon formation, three of the host sawflies eclosed in June but parasitoids did not emerge until November, at the end of the wet season ( Janzen 2006). Janzen (2006) noted that one parasitoid emerged from each cocoon, cutting a round hole through the side of the cocoon.

Gauld (1997) based his description on 3 ɗ 25 Ψ, with the holotype and several paratypes from Guanacaste National Park, Finca Jenny. A species nearly identical to P. adriani occurs Brazil but was respresented in the AEIC by only a single specimen. The difference in distribution makes it unlikely to be the same species, but since there is only a single specimen, we are reluctant to describe it as new.

Figures

FIGURES 9 – 12. Habitus and face. 9 – 10, Physotarsus adriani n. sp.; 9, habitus; 10, face. 11 – 12, P. albus n. sp.; 11, habitus; 12, face.