Blacus (Tarpheion) frontalis, Lu & Chai & Achterberg & Tang & Chen, 2024

Lu, Qian-Yu, Chai, Hong-Fei, Achterberg, Cornelis Van, Tang, Pu & Chen, Xue-Xin, 2024, Review of the subgenus Tarpheion of the genus Blacus Nees (Hymenoptera, Braconidae, Brachistinae) from China, with description of nine new species and eight new records, Zootaxa 5406 (2), pp. 297-335 : 310-312

Blacus (Tarpheion) frontalis sp. nov.

( Figs. 17–18 )

Material examined. Holotype: ♀, China, Zhejiang, Kaihua, Gutian Mtn , VII–VIII.1990, Xu Zhihong, No. 905658 ( ZJUH).

Description. Female. Length of body 2.35 mm, length of fore wing 2.0 mm.

Head. Antennomeres 19; length of first flagellomere 1.5 × length of second flagellomere; length of first, second and penultimate flagellomere 6.0, 4.0 and 2.0 × their width, respectively; length of maxillary palp 1.2 × height of head; occipital carina completely absent; medial part of frontal suture shallowly impressed; OOL: diameter of posterior ocellus: POL = 8:3:3; length of eye in dorsal view 2.2 × length of temple; face smooth, densely setose; malar suture present, length of malar space 0.67 × basal width of mandible.

Mesosoma. Length of mesosoma 1.5 × its height; side of pronotum largely smooth, remainder with a few striae ventrally ( Fig. 18E ); carinae of middle lobe of mesoscutum very short; precoxal sulcus short, only in middle of mesopleuron and shallowly crenulate ( Fig. 18E ); notauli complete, crenulate-rugose, wide and deep ( Fig. 18D ); mesoscutal middle lobe truncate anteriorly; scutellum smooth, its lateral carina complete, not protruding apically; surface of propodeum smooth between carinae, its medial area widened dorsally.

Wings. Fore wing: first discal cell widely truncate anteriorly; vein r vertical ( Fig. 18H ), length of vein r 1.1 × width of pterostigma; 1-CU1:2-CU1 = 1:7.

Legs. Hind coxa smooth, with weak oblique carinae; length of femur, tibia and basitarsus of hind leg 5.9, 12.2 and 7.0 × their width, respectively; fore claws with some brownish bristles ( Fig. 18I ), middle claws with two yellow bristles, hind claws with two yellow bristles.

Metasoma. Length of first tergite 2.75 × its apical width, slightly widened apically, superficially rugose ( Fig. 18G ); second tergite with longitudinal striae medially and remainder smooth ( Fig. 18G ); length of ovipositor sheath 0.26 × length of fore wing.

Colour. Yellow; 4 basal antennomeres yellow, 5–7th antennomeres yellowish-brown, remainder dark brown; parastigma whitish; second and third metasomal sternum yellowish; third and remainder metasomal tergites and sternites, pterostigma, veins, ovipositor and its sheath yellowish-brown; bristles of fore claws brownish, two bristles of middle claws yellow, two bristles of hind claws yellow; wing membrane slightly infuscate.

Male. Unknown.

Biology. Unknown.

Distribution. China (Zhejiang).

Etymology. The specific name frontalis refers to the depression of frons and is derived from “ frontis ” (Latin for fore part).

Notes. The new species is similar to B. (T.) javensis van Achterberg, 1976 because occipital carina is completely absent, antennomeres 19, precoxal sulcus reduced, first discal cell widely truncate anteriorly, notauli comparatively wide, length of ovipositor sheath approx. 0.3 × length of fore wing, medial area of propodeum distinctly widened dorsally, 4 basal antennomeres yellow, and yellow body, but differs by having distinct frontal suture (absent in T. javensis ), lamelliform carinae of middle lobe of mesoscutum very short (absent), second tergite with weak longitudinal striae medio-basally (smooth), 1-CU1:2-CU1 = 1:7 (1:30), length of eye in dorsal view 2.2 × length of temple (1.4 ×), length of first tergite 2.75 × (3.1 ×) its apical width, length of malar space 0.7 × basal width of mandible (equal), length of fore wing 2.35 mm (1.6 mm), and length of fore wing 2.0 mm (1.6 mm).

Figures

FIGURE 17. Tarpheion frontalis sp. nov. (body, lateral aspect).

FIGURE 18. Tarpheion frontalis sp. nov.. A. head, dorsal aspect; B. head, anterior aspect; C. antenna; D. mesosoma, dorsal aspect; E. mesosoma, lateral aspect; F. hind leg; G. propodeum and metasoma, dorsal aspect; H. fore wing; I. fore claw; J. ovipositor and ovipositor sheath.