Xynobius chrysops, Wu & Achterberg & Sheng & Chen, 2018

Wu, Qiong, Achterberg, Cornelis van, Sheng, Ying-yi & Chen, Xue-xin, 2018, A new genus from Vietnam (Hymenoptera, Braconidae, Opiinae), and the description of two new species, Journal of Hymenoptera Research 66, pp. 1-13 : 1

publication ID

https://dx.doi.org/10.3897/jhr.66.28881

publication LSID

lsid:zoobank.org:pub:155C57C6-E09F-49A8-BFB7-6FF4F7E82EA8

persistent identifier

https://treatment.plazi.org/id/024E09B3-B558-42F0-AADC-B671EF6CD9D8

taxon LSID

lsid:zoobank.org:act:024E09B3-B558-42F0-AADC-B671EF6CD9D8

treatment provided by

Journal of Hymenoptera Research by Pensoft

scientific name

Xynobius chrysops
status

sp. n.

Xynobius chrysops sp. n.

Figs 12-14 View Figures 12–14 , 15-23 View Figures 15–23

Type material.

Holotype, ♀ ( RMNH), "NW. Vietnam: Tonkin, Hoang Lien N.R. , 15 km W [of] Sa Pa, c. 1900 m, 15-21.x.1999, Malaise traps, C. v. Achterberg, RMNH’99” .

Description.

Holotype, ♀, length of body 3.3 mm, of fore wing 3.6 mm.

Head. Antenna with 35 segments, bristly setose and 1.3 times as long as fore wing; third segment 1.1 times as long as fourth segment, length of third, fourth and penultimate segments 5.0, 4.5 and 2.3 times their width, respectively (Figs 12 View Figures 12–14 , 22 View Figures 15–23 ); length of maxillary palp 1.2 times height of head; length of eye in dorsal view as long as temple (Fig. 21 View Figures 15–23 ); temple in dorsal view shiny, smooth, temple and vertex with adpressed setae; OOL: diameter of ocellus: POL= 1:1:3; face sparsely punctate, with a medio-longitudinal ridge extending to level of antennal sockets (Fig. 20 View Figures 15–23 ); frons glabrous behind antennal sockets; in front of anterior ocellus shiny, smooth and glabrous but laterally setose (Fig. 20 View Figures 15–23 ); labrum invisible; clypeus nearly semi-circular, with some oblique striae, convex but flattened ventrally, and its ventral margin truncate and narrow (Fig. 20 View Figures 15–23 ); clypeus 2.1 times wider than its maximum height and 0.6 times wider than face; hypoclypeal depression narrow, slit-shaped; mandible straight ventrally, hardly twisted, apically gradually narrowed and second tooth small; mandible and with narrow ventral carina (Fig. 20 View Figures 15–23 ); occipital carina remains far removed from hypostomal carina ventrally and horizontal dorsally, narrowly interrupted medio-dorsally; hypostomal carina narrow; malar suture distinct, narrow; length of malar space 0.9 times basal width of mandible.

Mesosoma. Length of mesosoma 1.5 times its height; dorsal pronope minute, round, (Figs 18 View Figures 15–23 , 21 View Figures 15–23 ); pronotal side largely smooth, but crenulate dorso-anteriorly and densely setose anteriorly and posteriorly (Figs 12 View Figures 12–14 , 17 View Figures 15–23 ); propleuron slightly convex, finely punctate and setose; epicnemial area densely setose dorsally, finely crenulate in groove ventrally; only anterior half of precoxal sulcus present, medium-sized and distinctly crenulate (Fig. 17 View Figures 15–23 ); remainder of mesopleuron smooth and shiny; pleural sulcus distinctly crenulate; mesosternal sulcus moderately deep, narrow and crenulate; postpectal carina absent; mesoscutum very shiny, finely punctate, with golden setae and smooth interspaces (Figs 13 View Figures 12–14 , 18 View Figures 15–23 ); notauli only anteriorly impressed, deep, narrow and crenulate and largely absent on disc; medio-posterior depression of mesoscutum droplet-shaped (Fig. 13 View Figures 12–14 ); scutellar sulcus deep and with 4 short crenulae, parallel-sided medially; scutellum convex and smooth, finely punctate and densely setose (Fig. 14 View Figures 12–14 ); side of scutellum and axilla densely golden setose, and lateral axillar lamella very wide (Figs 13 View Figures 12–14 , 14 View Figures 12–14 ); metanotum glabrous medially and densely setose laterally; antero-dorsal part of propodeum densely setose, rugose near transverse ridge and with medio-longitudinal carina; posterior part of propodeum largely smooth, and with 4 long and curved carinae (Fig. 14 View Figures 12–14 ).

Wings. Fore wing: 1-SR distinctly longer than wide and nearly linear with 1-M (Fig. 15 View Figures 15–23 ); pterostigma wide triangular; 1-R1 ending at wing apex and twice as long as pterostigma; r long and connected with 3-SR by obtuse angle; r:3-SR:SR1 = 6:33:58; 2-SR:3-SR:r-m = 8:11:4; 1-M slightly curved and SR1 straight; m-cu distinctly postfurcal and straight; cu-a distinctly postfurcal and 1- CU 1 slightly widened;1- CU 1:2- CU 1=1:18; first subdiscal cell closed and CU 1b medium-sized; entire M+ CU 1 sclerotized (Fig, 17). Hind wing: 1-M of hind wing straight, resulting in subparallel-sided cell apically; M+ CU:1-M:1r-m = 30:34:15; cu-a straight; m-cu unsclerotized, spectral; SR absent (Fig. 16 View Figures 15–23 ).

Legs. Length of femur, tibia and basitarsus of hind leg 4.1, 7.8 and 9.0 times as long as width, respectively (Fig. 23 View Figures 15–23 ); femur with long setae, tarsus and tibia densely setose; hind tibia slender medially; dorsally hind tibia with large smooth and glabrous patch subbasally (Fig. 23 View Figures 15–23 ).

Metasoma. Length of first tergite 1.7 times to its apical width, convex, its surface irregularly rugose medially (Fig. 19 View Figures 15–23 ), dorsal carinae strong and combined in its basal third and area below widely depressed, but dorsope small; second suture almost invisible; basal depressions of second tergite minute and tergite as long as third tergite, both with wide setose bands (Fig. 19 View Figures 15–23 ); second and following tergites smooth, shiny and setose posteriorly, especially densely in third tergite; combined length of second and third metasomal tergites 0.4 times total length of metasoma; setose part of ovipositor sheath 0.07 times as long as fore wing (exposed sheath 0.11 times), 0.6 times first tergite (entire sheath as long as tergite), and 0.2 times hind tibia (entire sheath 0.4 times); hypopygium about 0.3 times as long as metasoma, truncate apically and not reaching apex of metasoma (Fig. 23 View Figures 15–23 ).

Colour. Blackish brown, but scape, pedicellus, mandible (but teeth dark), tegulae, fore coxa dorsally, fore femur laterally and ventrally, fore tibia basally, trochantellus dorsally, second tergite laterally yellowish brown; ventral margin of clypeus, pterostigma and veins, markings of fore wing near veins r, 1-SR+M, 2-SR, basal half of 3-SR, m-cu, basal of second discal cell and second subdiscal cell, fore femur dorsally, trochanter dorsally, tarsus (but pale basally), second tergite medially and following tergites dark brown; palpi, inner side of fore coxae, trochanter ventrally, middle and hind tibia basally pale yellowish; setae on vertex, temple, mesoscutum, scutellum, side of scutellum and metanotum golden, remainder of setae silvery; remainder of fore wing membrane subhyaline.

Distribution.

Vietnam.

Biology.

Unknown.

Notes.

This aberrantly coloured new species belongs to a small group of Asian spp. near Xynobius maculipennis (Enderlein, 1912) united by the subbasally widened hind tibia with the resulting small knob glabrous and shiny dorsally, the hypopygium dark brown, the head and mesoscutum densely pubescent, and the fore wing with a large Y-shaped dark brown area below para- and pterostigma (Fig. 15 View Figures 15–23 ). The new species differs from all other species examined by having the third metasomal tergite with a wide band of setae apically (Fig. 19 View Figures 15–23 ; narrow in other species); fore wing infuscate apically (Fig. 15 View Figures 15–23 ; subhyaline); the hypoclypeal depression nearly absent (distinct); the head and mesosoma dark golden pubescent combined with a slender first tergite (slightly widened apically and 1.6 × longer than its apical width; other species have usually pale yellowish or silvery pubescence, if dark golden than first tergite 1.2-1.3 times as long as wide apically).

Etymology.

Named after the partly golden setosity; “chrysops” is Greek for “gold-coloured”.

RMNH

Netherlands, Leiden, Nationaal Natuurhistorische Museum ("Naturalis") [formerly Rijksmuseum van Natuurlijke Historie]

CU

USA, New York, Ithaca, Cornell University

RMNH

National Museum of Natural History, Naturalis

CU

Cornell University

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Hymenoptera

Family

Braconidae

Genus

Xynobius