Proantrusa tridentate Zheng, van Achterberg & Chen, 2016

Zheng, Min-Lin, Achterberg, Cornelis van & Chen, Jia-Hua, 2016, A new species of the genus Proantrusa Tobias (Hymenoptera: Braconidae: Alysiinae) from northwestern China, Florida Entomologist 99 (3), pp. 385-388 : 387-388

Proantrusa tridentate Zheng, van Achterberg & Chen sp. nov.

This new species is similar to Laotris striatula (Haliday, 1839) because of the smooth 3rd metasomal tergite and the well-exposed 4th tergite of female, but P. tridentata has 1) the mandible with 3 teeth; 2) the frons with a small acute tubercle in front of the anterior ocellus; and 3) the pterostigma of the fore wing being rather short and subtriangular.

Description

Female (HOLOTYPE). Body length 4.0 mm; fore wing length 3.4 mm.

Head. Antenna with 31 segments, its length equal to the length of fore wing, 1st flagellomere 1.3 times as long as 2nd flagellomere. First, 2nd, and penultimate flagellomeres 2.5, 1.7, and 1.6 times as long as their maximum width, respectively. Head, in dorsal view, somewhat transverse, 2.1 times as wide as its median length. Eye 1.4 times as long as temple, temple slightly narrowed behind eye ( Fig. 2 ). Ratio OOL:OD:POL = 20:8:7. Mandible ( Figs. 1 and 2 ) 3-den- tate, tooth somewhat curved outwards. Tooth 2 acute and equilateral-sided, tooth 1 and tooth 3 obtuse, tooth 3 somewhat longer than tooth 1 and tooth 2. Maxillary palp with 6 segments, 1.2 times as long as height of head. Face 1.7 times as wide as high, punctate, mainly glabrous, sparsely pubescent on area close to eyes and with a weak medio-longitudinal carina. Frons glabrous and smooth, with a small acute tubercle in front of anterior ocellus ( Fig. 2 ), slightly depressed near antennal sockets; clypeus hemi-circular ( Fig. 1 ).

Mesosoma. Length of mesosoma 1.5 times its height. Propleuron largely crenulate-rugose and glabrous. Anterior area of mesoscutum densely pubescent and remainder only sparsely setose. Notauli absent on mesoscutal disk but impressed and crenulate on oblique anterior part of mesoscutum. Medio-posterior depression at posterior third of mesoscutum narrow, deep and crenulate ( Fig. 5 ). Scutellar sulcus wide and distinctly crenulate, axilla densely white setose. Scutellum rather convex, mainly glabrous but laterally sparsely setose. Metanotum with a strong median spine ( Fig. 6 ). Propodeum gradually lowered posteriorly, largely reticulate-rugose ( Fig. 7 ) and sparsely setose. Mesopleuron mainly glabrous and smooth. Precoxal sulcus rather wide and shallow, rugulose ( Fig. 6 ). Mesopleural furrow finely crenulate dorsally and coarsely crenulate ventrally ( Fig. 6 ). Metapleuron mainly smooth, posteriorly densely setose which setae directed to hind coxa ( Fig. 6 ).

Wings. Length of fore wing 2.5 times as long as wide. Pterostigma rather short, subtriangular, 3.2 times as long as wide. Vein r arising just before middle of pterostigma. Vein 1-R1 1.4 times as long as pterostigma. Vein 3-SR+SR1 slightly curved posteriorly. Vein r 0.9 times as long as maximum width of pterostigma, 0.4 times as long as vein 1-SR+M, 0.2 times as long as vein 3-SR+SR1; vein 1-SR 7 times longer than its minimum width ( Fig. 3 ); vein SR1 distinctly curved below level of connection of veins 2-SR and r ( Fig. 3 ); vein 1-SR+M somewhat curved. Vein m-cu antefurcal. Hind wing 3.1 times as long as its maximum width.

Legs. Hind coxa smooth and finely setose. Hind femur 3.9 times as long as wide. Hind tibia 1.1 times as long as tarsus. Basitarsus 3.7 times as long as wide, 1.8 times as long as 2nd tarsal segment, 0.6 times as long as 2nd to 5th segments combined ( Fig. 4 ). The inner and outer tibial spurs of hind leg 0.4 and 0.3 times as long as basitarsus, respectively.

Metasoma. First tergite distinctly longitudinally striate, its length nearly equal to its apical width, evenly widened from base to apex, its dorsal carinae remain separated. Second tergite almost entirely longitudinally striate, only laterally smooth, its median length 0.4 times its apical width. Third and following tergites smooth and nearly glabrous, 3rd tergite as long as 2nd tergite. Ovipositor short, but slightly project- ing beyond the apical tergite in the retracted position, its setose part 0.2 times as long as hind tibia.

Color. Black. Antenna dark brown except yellow base of scapus. Clypeus brownish yellow, labrum and palpi yellowish, mandible yellow but its middle tooth yellowish brown. Pterostigma and most veins of hind wing yellowish brown. Legs mainly yellow but tarsi and apical part of hind tibia brown. First and 2nd tergites dark reddish brown, 3rd to 5th tergites mainly reddish brown but basally yellowish brown to yellow, remainder of metasoma yellowish brown to yellow; ovipositor sheath yellowish brown.

Male. Similar to female but antenna with 34 segments and precoxal sulcus distinctly crenulate.

Habitat and Natural History

Unknown. Material Examined

HOLOTYPE: 1 ♀, CHINA, Ningxia, Liupan Mountain , 22-VIII-2001, collected by Guanghong Liang, deposited in Beneficial Insects Institute, Fujian Agriculture and Forestry University . PARATYPE: 1 ♁, China, Ningxia, Liupan Mountain , 17-VIII-2001, collected by Zhihui Lin, deposited in Beneficial Insects Institute, Fujian Agriculture and Forestry University .

Distribution

Known only from the type locality in Ningxia (northwest China) .

Etymology

Named afer the three- (“tri” in Latin) toothed (“dentatus” in Latin) mandible.

Figures

Figs. 1–9. Proantrusa tridentata sp. nov., female, holotype. 1, Head (frontal view); 2, head (dorsal view); 3, forewing; 4, hind tarsus;5, mesosoma (dorsal aspect); 6, mesosoma (lateral aspect); 7, propodeum; 8, metasoma (dorsal view with T1–4 visible); 9, metasoma (lateral aspect).