Psyttalia quadrinervis Long, 2024

Oanh, Nguyen Thi, Long, Khuat Dang, Xuan, Trinh Thi, Tinh, Duong Van & Nghiep, Hoang Thi, 2024, The genus Psyttalia Walker (Hymenoptera, Braconidae) in Vietnam: descriptions of seven new species and their host information, Zootaxa 5477 (1), pp. 1-26 : 14-17

Psyttalia quadrinervis Long , sp. nov.

Figures 9 , 10

Type material. Holotype, ♀, “Opii. 107 ” ( IEBR), N Vietnam: Ninh Binh, Cuc Phuong NP , Bong center , forest, 20°20’N 105°45’E, 200 m, light trap, 15.v.2015, KD Long.

Paratype, 1♂, “Opii. 313 ” ( IEBR), SC Vietnam: Quang Ngai, Ly Son Isl., An Vinh , sweep (net), 16.viii.2017, DT Hoa . Paratypes, 2 ♀, “Opii. 114 ” (IEBR), NE Vietnam: Vinh Yen, Me Linh, Ngoc Thanh , fruit orchard, MT, 25.x.2000, KD Long; “Opii. 321 ” ( IEBR), NC Vietnam: Ha Tinh, Huong Son, Vu Quang NP, forest, 18°22’N 106°13’ 450m, sweep (net), 28.ix.2009 KD Long .

Comparative diagnosis. Psyttalia quadrinervis , sp. nov. shares relatively long vein r of fore wing and curved vein m-cu with two species known from China, P. fletcheri , and P. makii , but the new species differs from both by having: 1) vein cu-a of fore wing nearly interstitial (square) or slightly postfurcal (vs 1-CU1 at most 0.7 × cu-a in P. fletcheri , and about of equal length in P. makii ; 2) first subdiscal cell of fore wing widened posteriorly (vs first subdiscal cell of fore wing nearly parallel-sided in P. fletcheri and P. makii ); and 3) vein 2-SR+M of fore wing 1.5–2.0 × its maximum width (vs about twice as long as wide in P. fletcheri and P. makii ). The new species is also close to P. mangiferae , sp. nov. but differs from the latter by having: 1) ventral margin of clypeus convex medially (vs straight in P. mangiferae ); 2) notauli absent anteriorly and on disc of mesoscutum (vs notauli anteriorly as pair of partly finely crenulate impressions); and 3) pterostigma broad triangular in shape (vs narrow triangular in shape in P. mangiferae ).

Description. Holotype, ♀, length of body 4.0 mm, fore wing 4.6 mm, length of visible ovipositor 2.0 mm ( Fig. 9 ).

Head. Antenna incomplete, with 43 flagellomeres remaining, flagellomeres bristly; first flagellomere 1.1 × as long as second; length of first and second flagellomeres 2.6 and 2.3 × their width, respectively; length of maxillary palp 1.1 × height of head; in dorsal view, head 1.9 × as wide as long medially; length of eye 3.8 × temple ( Fig. 10A ); temple shiny, smooth and with sparse setae; OOL: OD: POL = 7: 5: 3; in lateral view, medially eye 1.5 × as long as wide and 3.2 × as wide as temple ( Fig. 10C ); ventral margin of clypeus convex medially ( Fig. 10B ); width of clypeus 3.2 × its maximum height, 1.2 × height and 0.8 × width of face, respectively; hypoclypeal depression wide and deep ( Fig. 10B ); distance between tentorial pits 4.0 × distance from pit to eye margin; malar space narrow, 0.6 × basal width of mandible; clypeus rugulose; face rugo-punctate with distinct raised carina medially ( Fig. 10B ); mandible not twisted, apically moderately narrowed and with both teeth wide, normal basally and with narrow ventral carina ( Fig. 10B ); occipital carina remains far removed from hypostomal carina and dorsally largely absent; frons nearly flat, slightly depressed laterally, with round pit between antennal sockets, smooth medially ( Fig. 10A ); vertex and temple smooth.

Mesosoma. Laterally, length of mesosoma 1.3 × its height ( Fig. 10E ); pronope absent, only with groove; pronotal side largely smooth, but anterior and posterior grooves present, and anteriorly with some crenulae ( Fig. 10E ); propleuron flattened; epicnemial area smooth dorsally; precoxal sulcus rather deep and moderately crenulate ( Fig. 10E ); remainder of mesopleuron smooth and shiny; pleural sulcus smooth ventrally; mesosternal sulcus narrow and finely crenulate; postpectal carina absent; mesoscutum very shiny and nearly entirely glabrous ( Fig. 10D ); notauli only anteriorly as pair of partly smooth impressions and largely absent on disc, mesoscutum flat posteriorly; scutellar sulcus deep and crenulate, concave medially, and 0.2 × as long as scutellum; scutellum slightly convex and smooth, only apically sparsely setose; metanotum with short longitudinal carina anteromedially and short carina posteriorly ( Fig. 10D ); propodeum with lateral carinae above spiracle, surface of propodeum smooth, except for some punctures near middle of reversed Y-shaped median carina ( Fig. 10G ).

Wings. Fore wing: 1-SR as long as wide and not linear with 1-M; pterostigma broad triangular in shape; length of pterostigma 3.1 × as long as its width medially ( Fig. 10H ); 1-R1 ending at wing apex and 1.5 × as long as pterostigma; r exiting before middle of pterostigma, not linear with 3-SR; r-m and most of 1-SR+M sclerotized; vein r = 0.9 × 2-SR; vein 2-SR+M of fore wing 1.5 × its maximum width; r: 3-SR: SR1 = 10: 26: 52; 2-SR: 3-SR: r-m = 11: 26: 15; 1-M straight; SR1 evenly curved throughout; m-cu narrowly antefurcal and strongly curved, not linear with 2-SR+M ( Fig. 10H ); subdiscal cell strongly narrowed anteriorly ( Fig. 10H ); M+CU1 widened apically; cu-a short, nearly interstitial, cu-a 0.2 × 2-CU1; only apex of M+CU1 sclerotized. Hind wing with vein 2-M slightly sinuate; M+CU: 1-M: 1r-m = 18: 22: 12; cu-a straight; m-cu and SR absent ( Fig. 10I ).

Legs. Length of femur, tibia and basitarsus of hind leg 4.5, 10.8 and 5.2 × as long as wide, respectively; hind basitarsus 0.3 × hind tibia, and 0.6 × second–fifth tarsus combined; inner and outer spurs 0.5 and 0.4 × basitarsus, respectively; hind tibia and tarsus with long setae.

Metasoma. Length of first tergite 1.2 × its apical width, convex medio-posteriorly, its surface largely smooth except coriaceous area medially ( Fig. 10F ), dorsal carinae strong in basal 0.8 of tergite and with depressed area below; second suture indistinct; combined length of second and third metasomal tergites 0.5 × the remaining tergites posteriorly; first tergite smooth basally and apically, superficially sculptured medially; second and following tergites smooth, sparsely setose apically and ventrally.

Colour. Yellow; antenna yellow; head yellow but stemmaticum dark brown; palpi pale yellow; mesosoma yellow; all legs yellow, except hind first–fourth tarsus brown; tegula yellow; pterostigma yellow basally, yellowish brown apically; wing membrane subhyaline, veins brown; metasoma yellow entirely; ovipositor sheath brown; ovipositor yellow.

Variation. Paratypes, 2♀, antenna with 50 flagellomeres; body length 3.3–3.5 mm, fore wing 3.5–3.8 mm, length of visible ovipositor 2.0– 2.3 mm; vein cu-a of fore wing slightly postfurcal or subinterstitial; 2-SR+M of fore wing 1.7–2.0 × as long as its maximum width. Paratype, 1♂, antenna with 48 flagellomeres; length of body 3.4 mm, fore wing 3.1 mm.

Distribution. N Vietnam (Ninh Binh, Cuc Phuong NP), NE Vietnam (Phuc Yen), NC Ha Tinh (Huong Son), SC Vietnam (Quang Ngai, Ly Son Isl.).

Biology. Unknown.

Etymology. From “quadrus” (Latin for “square”) and “nervus” (Latin for “vein”) because fore wing with square-shaped vein 1-CU1.

Figures

FIGURE 9. Habitus of Psyttalia quadrinervis Long, sp. nov., holotype, female, lateral.

FIGURE 10. Psyttalia quadrinervis Long, sp. nov. A Head, dorsal B Head, frontal C Head, lateral D Mesonotum E Mesopleuron F Metasoma G Propodeum H Fore wing I Hind wing.