Centistes bicaudatus Aguirre, Almeida & Shaw

Aguirre, Helmuth, Almeida, Luis Felipe Ventura De & Shaw, Scott Richard, 2017, Revision of the genus Centistes (Hymenoptera: Braconidae: Euphorinae: Centistini) of Costa Rica, Zootaxa 4216 (1), pp. 1-46 : 14-15

Centistes bicaudatus Aguirre, Almeida & Shaw , sp. n.

( Figs 57–63 )

Female. Body length ( Fig. 57 ): 2.3–2.6 mm. Body color: head black, except pedicel and scape yellow, and flagellomeres dark brown; mesosoma black-dark brown, except legs yellow; wings hyaline; metasoma dark brown except T1 black. Head ( Figs. 58–59 ): antenna with 22 flagellomeres; flagellar length/width ratios as follows: F1 = 3.0, F10 = 2.0, F22 = 1.7; last flagellomere terminating apically in a sharp point; pedicel as long as wide; scape 1.5–2.0 × longer than wide; mandibles when closed overlapping for 0.2–0.7 × mandible length; mandible width basally 0.4–0.6 × mandible length; malar space 0.2 × eye height, and 0.7–1.2 × basal mandible width; gena sparsely pubescent; shortest distance between eyes 0.8–1.0 × clypeus width; eye in lateral view 1.7–1.9 × taller than wide; lateral ocellus separated from compound eye by a distance 1.2–1.5 × ocellar width; frons glabrous; vertex with a few scattered setae; temple with few scattered setae; temple width 0.7 × eye width; occipital carina thick and complete. Mesosoma: pronotum glabrous; pronotum in lateral view mostly smooth, medially foveate, posteriorly carinate; propleuron either smooth or with anterior and medial margins rugose; median mesonotal lobe anteriorly pubescent, posteriorly glabrous; lateral mesonotal lobes glabrous, except lateral borders pubescent; notauli either absent or only present anteriorly ( Fig. 61 ); pit on mesoscutum small and oval ( Fig. 61 ); scutellar sulcus with one carina; scutellar disc pubescent; mesopleuron centrally glabrous, borders and area below precoxal sulcus pubescent; precoxal sulcus foveate; metanotum smooth or carinate; metapleuron pubescent; propodeum pubescent except dorsum glabrous; propodeum subdivided into anterior and posterior halves by a strong transverse carina, and either with or without a median-longitudinal dorsal carina ( Fig. 60 ); propodeum with surfaces mostly smooth except laterally rugose. Legs: hind coxa 1.3–1.4 × longer than middle coxa; hind femora length 4.4–4.9 × maximum width; hind tibia length 9.2–12.5 × longer than maximum width; hind tibial spur 0.4–0.5 × as long as hind basitarsus; ratio of hind tarsomeres from basitarsus apically 14:8:6:4:8. Wings: fore wing length 2.1–2.5 mm; pterostigma 2.9–3.6 × longer than maximum width; length of marginal cell 2R1 along anterior wing margin 0.8– 1.0 × the length of pterostigma; vein r-rs 0.4–0.5 × as long as pterostigma width; vein Rs+M present as a short stub; vein m-cu basal with vein RS; hind wing with three sickle-shaped hamuli. Metasoma: first tergite basally 0.7–0.8 × as wide as apical width, and 1.5–1.7 × longer than apical width; sculpture of first tergite longitudinally costate with costae almost parallel ( Fig. 62 ); spiracle of tergum one situated on lateral margin near the basal quarter of segment; hypopygium ventrally flat, and with a pair of large claspers ( Fig. 63 ); ovipositor sheath 1.7–1.9 × longer than basal width, and 0.9–1.2 × as long as basitarsus; ovipositor sheath densely pubescent, with apex truncated ( Fig. 63 ).

Male. Unknown.

Holotype female. COSTA RICA: San Jose, Zurqui de Moravia , 1600 m, vi.1990, P. Hanson leg., Malaise. Deposited in UWIM.

Paratypes. COSTA RICA: Three females, San Jose, Zurqui de Moravia , 1600 m, vii.1991, P. Hanson leg., Malaise. One female , San Jose, Zurqui de Moravia , 1600 m, vii.1990, P. Hanson leg., Malaise. One female , San Jose, Zurqui de Moravia , 1600 m, v.1992, P. Hanson leg., Malaise. One female , San Jose, Zurqui de Moravia , 1600 m, xi.1995, P. Hanson leg., Malaise. One female , San Jose, Zurqui de Moravia , 1600 m, x-xi.1991, P. Hanson leg., Malaise. Six females , San Jose, Zurqui de Moravia , 1600 m, x.1995, P. Hanson leg., Malaise. One female , Cartago, La Cangreja , 1950 m, vii.1991, P. Hanson leg., Malaise. All paratypes deposited in UWIM.

Comments. Centistes bicaudatus and C. chorotegus both have distinctive clasper-like structures on the hypopygium, but C. bicaudatus is easy to recognize by the presence of a pit on mesoscutum (pit absent in C.

chorotegus ). The unusual modifications of the hypopygium in these species are presumed to be an adaptation to better gripping the host during oviposition.

Etymology. The name of this species is formed by the Latin prefix “bi”, meaning two, and the Latin stem “caudatus”, meaning tail, describing the two features located on the hypopygium.

Figures

FIGURES 57 – 63. Centistes bicaudatus sp. n. 57) Lateral habitus, 58) anterior head, 59) dorsal head, 60) propodeum, 61) mesoscutum, 62) dorsal metasoma, 63) lateral metasoma showing apically ovipositor sheaths and ventrally clasper-like structures (arrow).