Trichacis acuminata Arias-Penna & Masner

Arias-Penna, Tania Milena, Masner, Lubomir & Delsinne, Thibaut, 2012, Revision of the Neotropical species of Trichacis Foerster (Hymenoptera: Platygastroidea: Platygastridae), with description of 24 new species, Zootaxa 3337, pp. 1-56: 7

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Trichacis acuminata Arias-Penna & Masner

new species

Trichacis acuminata Arias-Penna & Masner  , new species

Figures 1View FIGURE 1 G, 1 H; 2 A– 2 C

Female. Body length: 1.80 mm (holotype); 2.25 mm (paratype); mean length ± SD = 2.03 ± 0.32 mm.

Black; radicle and base of A 1 yellow; distal part of A 1 brown and A 2 –A 10 dark brown; mandible brown with apex dark brown; fore leg yellow except apical tarsi brown; mid leg brown except basal 2 / 3 of tibia and 1–4 tarsi yellow; hind leg brown, base of trochanter, apical 2 / 3 of femur, apical 2 / 3 of tibia and tarsi darker; coxae dark brown; fore wing infuscate in posterior 2 / 3, with darker and lighter patterns in basal 1 / 3.

Head, in dorsal view, two times as wide as long; EH < IOSAbout IOS; interocellar area finely coriaceous; OOL > LOL; antennal clava 4 -segmented; A 1 not reaching vertex dorsal margin; A 2 –A 5 longer than wide; A 6 as long as wide; A 7 –A 9 wider than long; base of mandible smooth; frons above torulus coriaceous, and with transverse striae; interantennal process smooth, slightly curved down and surpassing ventral border of torulus; clypeus exposed; clypeal margin truncate; gena smooth; lateral parts of vertex coriaceous between posterior ocellus and hyperoccipital carina, and coriaceous and longitudinally striate between hyperoccipital carina and occipital carina; temple projection present; hyperoccipital carina incomplete, fading until reaching level of imaginary line connecting eye inner margin to posterior cephalic margin; distance between posterior ocellus and hyperoccipital carina longer than posterior ocellus diameter.

Mesosoma slightly arched; antero-admedian line present; notaulus anteriorly incomplete; lateral notaular area with coriaceous sculpture along its anterior margin and inter-notaular area with anterior 1 / 3 coriaceous and posterior 2 / 3 smooth; posteromedial region of inter-notaular area convex; parapsidal line present; central pronotal area smooth; specialized area of mesoscutellum heart-shaped and elevated; median projection of specialized area of mesoscutellum subtriangular; mesopleural carina incomplete (length of mesopleural carina/length of mesopleuron = 0.52); fore wing distinctly surpassing apex of metasoma.

Metasoma elongate; combined length of T 3 –T 6 <T 2; T 1 as long as wide; T 2 longer than wide; T 3 –T 6 wider than long; anteromedial part of T 2 smooth and concave; T 6 subtriangular; T 3 –T 6 densely and deeply punctulate.

Male. Body length: 1.90 mm (allotype).

Similar to female except the following: A 1 –A 5 yellow; A 6 –A 10 brown; fore and mid legs yellow; hind leg yellow except brown coxa, tarsal segments and apical 1 / 3 of femur and tibia; wing infuscate in posterior 2 / 3, with darker and lighter patterns in basal 1 / 3; antenna filiform; A 2 –A 4, A 6 –A 10 longer than wide; A 5 as long as wide.

Etymology. The name of the species refers to the temple projection.

Diagnosis. Both Trichacis acuminata  and T. acuta  have temple projection but may be distinguished by the sculpture on the medial area of vertex, which is covered by striae in T. acuminata  and smooth in T. acuta  , and by the shape of the anteromedial part of T 2, which is concave in T. acuminata  and flat in T. acuta  . Interestingly, the Neartic species Trichacis bison  , T. cornuta  , and T. dracula  also have temple projection ( Masner 1983).

Material examined. Holotype: 1 Ƥ; BOLIVIA, Cochabamba, montane & cloud forest, 17 º08´ 52 ´´S 65 º 42 ´ 54 ´´W, 1800 m, February 6–8 1999, FIT, F. Génier ( CNCIAbout CNCI); allotype: 1 3, La Paz, Chulumani, Apa-Apa, 16 º 22 ´S 67 º 30 ´W, 1800 m, May 1–4 1997, L. Masner ( CNCIAbout CNCI); paratype: 1 Ƥ, with same data as holotype ( ICNAbout ICN). Holotype is deposited in CNCIAbout CNCI.


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Canadian National Collection Insects


Instituto de Ciencias Naturales, Museo de Historia Natural