Spathius austroarabicus Belokobylskij, 2021

Belokobylskij, Sergey A. & Achterberg, Cornelis Van, 2021, Review of the braconid parasitoid subfamily Doryctinae (Hymenoptera, Braconidae) from the United Arab Emirates and Yemen, European Journal of Taxonomy 765 (1), pp. 1-143 : 43-47

Spathius austroarabicus Belokobylskij sp. nov.

urn:lsid:zoobank.org:act:7D9A7222-329E-46BD-A938-1E5609144351

Figs 18–19

Comparative diagnosis

This species belongs to the S. apidanus species-group (formerly a monotypic group from the Aru Islands) according to the position of its recurrent vein (m-cu) of the fore wing, arising from the parallel vein (CU1a) at a long distance from the apex of the brachial (subdiscal) cell, and the entirely smooth metasomal tergites behind the petiole. This new species distinctly differs from S. apidanus Nixon, 1943 by several diagnostic characters: vertex smooth (striate in S. apidanus ), pronotal keel widely fused with posterior margin of pronotum in dorsal view (free and widely separated in S. apidanus ), mesoscutum without transverse rugae on lateral lobes (with distinct additional rugae in S. apidanus ), hind femur elongate-oval (claviform in S. apidanus ), fore wing hyaline (dark brown with submedian pale facia in S. apidanus ), petiole of metasoma rather short and wide, about 1.5 times longer than propodeum (very long and narrow, about 2.5 times longer in S. apidanus ), ovipositor sheath distinctly shorter than metasoma (as long as body in S. apidanus ), and body brownish yellow (dark brown in S. apidanus ).

Spathius austroarabicus sp. nov. may also include in the S. capaneus species-group in the section with a smooth tergite behind the petiole, having the hind tibia clothed only with very short setae, which are much shorter than the width of the tibia. This new species is similar in this group to S. semele Nixon, 1943 , from Philippines, but differs from it by having the recurrent vein (m-cu) of the fore wing arising from the apex of brachial (subdiscal) cell (recurrent vein (m-cu) arising from the parallel vein (CU1a) at a long distance from the apex of the brachial (subdiscal) cell in S. semele ), hind coxa and tibia entirely yellow (coxa brown and tibia darkened in posterior 0.7 in S. semele ), and ovipositor sheath distinctly shorter than the metasoma (as long as body in S. semele ).

Etymology

Named from the combination of the Latin words ‘ australis ’ (= south) and ‘ arabicus ’ (= Arabian), since this species was found in the southern part of the Arabian Peninsula.

Material examined

Holotype YEMEN • ♀; “Yemen (no 2989), Ta’izz, light trap, 1–3.iv.1998, A.v. Harten & Ahmad Ahwad, RMNH’98”; RMNH.

Description

Female

MEASUREMENTS. Body length 2.6 mm; fore wing length 2.0 mm.

HEAD. Head width (dorsal view) 1.4 times its median length, 1.2 times width of mesoscutum. Vertex weakly convex. Head behind eyes (dorsal view) rather weakly and evenly roundness decreased. Transverse diameter of eye (dorsal view) 1.8 times longer than temple. Ocelli small, in almost equilateral triangle. POL almost equal to Od, 0.25 times OOL. Eye glabrous, in lateral view oblique, its maximum diameter 1.3 times minimum diameter. Malar space 0.8 times maximum diameter of eye, almost equal to basal width of mandible. Face weakly convex, its width 1.2 times maximum diameter of eye, 1.2 times height of face and clypeus combined. Clypeal suture almost complete, distinct laterally but very fine dorsally. Ventral margin of clypeus with distinct narrow flange. Hypoclypeal depression medium-sized and rounded, its width 0.8 times shortest distance from edge to eye, 0.4 times width of face. Occipital carina dorsally complete and not broken toward ocellar triangle, not reaching below hypostomal carina and obliterated rather long distance before mandible base. Hypostomal flange narrow.

ANTENNA. Atenna slender, weakly setiform, 21-segmented, 1.1 times longer than body. Scape 1.3 times longer than its maximum width. First flagellar segment 6.0 times longer than apical width, 0.95 times as long as second segment. Penultimate segment 4.7 times longer than width, 0.7 times as long as first segment, 0.9 times as long as apical segment; latter acuminate apically and without spine.

MESOSOMA. Mesosoma not depressed, its maximum length 1.8 times its maximum height. Pronotal carina distinct, its anterior branch situated submedially and far separated from posterior margin of pronotum. Pronotal lateral depression distinct, densely crenulate, delineated below by carinae. Mesoscutum (lateral view) high, subroundly and curvedly elevated above pronotum, its median lobe (dorsal view) distinctly convex anteriorly and without anterolateral corners, with rather distinct and sculptured longitudinal median furrow in posterior half; mesoscutum in dorsal view 0.9 times as long as wide. Notauli complete, rather wide, deep anteriorly and shallow posteriorly, sparsely crenulate. Prescutellar depression rather deep, relatively wide, with distinct median carina, finely rugulose-carinate, 0.4 times as long as scutellum. Scutellum weakly convex, with distinct lateral carinae, almost as long as its maximum anterior width. Subalar depression rather wide, shallow, reticulate-rugulose. Precoxal sulcus deep, wide, short, densely crenulate, running along anterior 0.4 of lower part of mesopleuron. Postpectal carina absent. Metanotum with low, wide below and distally acuminate medio-dorsal tubercle (lateral view). Metapleural flange (lobe) narrow, distinct, subrounded. Propodeum roundly convex, without lateral tubercles.

WINGS. Fore wing 3.8 times longer than wide. Pterostigma wide, 3.6 times longer than its maximum width. Radial vein (r) arising almost from middle of pterostigma. Radial (marginal) cell not shortened, metacarpus (1-R1) 1.4 times longer than pterostigma. Second radial abscissa (3-SR) 5.5 times longer than first abscissa (r) and forming with it weakly obtuse angle, 0.6 times as long as the mainly straight, but weakly curved apically third abscissa (SR1), 1.3 times as long as straight first radiomedial vein (2- SR). Second radiomedial (submarginal) cell weakly narrowed distally, its length 3.0 times maximum width, 1.9 times length of brachial (subdiscal) cell. Second abscissa of medial vein (2-SR+M) long, 0.7 times as long as recurrent vein (m-cu). Nervulus (cu-a) almost interstitial. Mediocubital vein (M+CU1) weakly sinuate and almost not curved to longitudinal anal vein (1-1A). Narrow brachial (subdiscal) cell closed apically weakly before recurrent vein(m-cu). Parallel vein (CU1a) interstitial. Hind wing 6.2 times longer than its maximum width. First costal abscissa (C+SC+R) 0.4 times as long as second abscissa (1-SC+R). First abscissa of mediocubital vein (M+CU) 0.5 times as long as second and third abscissa (1-M) combined. Recurrent vein (m-cu) short, unsclerotised but pigmented, weakly antefurcal, curved towards base of wing.

LEGS. Fore tibia anterior margin with short, rather dense spines arranged in long single line. Segments of middle tarsus distinctly longer than their width. Hind coxa rather short, with basoventral corner and tubercle, 1.4 times longer than maximum width. Hind femur thickened, elongate-oval, 3.4 times longer than wide. Hind tibia with several slender spines on outer distal margin. Hind tarsus 0.85 times as long as hind tibia. Hind basitarsus thickened, 0.6 times as long as remaining segments combined. Second segment of hind tarsus 0.5 times as long as basitarsus, 1.1 times longer than fifth segment (without pretarsus). Tarsal segments mainly slender.

METASOMA. Petiole in lateral view, ventrally almost straight, dorsally weakly arched in anterior half and almost straight in posterior half, highest in anterior fourth; in dorsal view, petiole rather slender, distinctly evenly widening towards apex in posterior third, with distinct spiracular tubercles in anterior third and fine dorsope. Length of petiole 1.85 times its posterior width, 1.6 times length of propodeum; its posterior width 1.6 times its width at spiracular level, 2.5 times its minimum anterior width. Second to sixth tergites without laterotergites separated; second and third lateral parts of tergites fused. Second suture absent. Median length of second and third tergites combined 1.1 times anterior width of second tergite, 0.6 times their maximum width. Ovipositor straight. Ovipositor sheath as long as petiole, 0.33 times as long as metasoma, 0.55 times as long as mesosoma, 0.2 times as long as fore wing.

SCULPTURE AND PUBESCENCE. Head mainly smooth, with fine and short aciculation near ocelli; face smooth medially, finely and obliquely aciculate laterally and transversely ventrally. Mesoscutum densely granulate, with two convergent posteriorly distinct longitudinal carinae in posterior half and rugulosity between carinae; scutellum entirely and distinctly granulate. Mesopleuron mainly and densely granulatereticulate, almost smooth below precoxal sulcus. Propodeum with areas distinctly delineated by carinae, almost entirely transversely striate-rugulose; medio-basal carina medium length, 1.5 times as long as anterior fork of areola; areola short and wide, 1.3 times as long as maximum width. Hind coxa weakly rugulose- coriaceous in anterior half and smooth on other part; hind femur mainly smooth, dorsally partly rugulose-aciculate. Petiole distinctly striate with long and subparallel dorsal carinae, densely rugulose-reticulate in medial area in anterior half. Remainder tergites entirely smooth. Vertex mainly glabrous, with short and sparse white setae laterally. Mesoscutum mainly glabrous, with long and sparse white setae arranged along notauli and laterally. Setae of hind tibia semi-erect, short and rather dense, their length on dorsal surface about 0.7 times maximum width of tibia.

COLOUR. Head dorsally, mesosoma and petiole yellowish brown; head in lowed half and metasoma behind petiole yellow. Palpi pale yellow. Antenna yellow basally, mainly pale brown to dark brown apically.

Legs mainly brownish yellow, all coxae yellow. Ovipositor sheath dark brown, but pale anteriorly. Fore wing hyaline. Pterostigma dark brown medially, whitish or pale yellow in basal 0.4 and shortly apically.

Male

Unknown.

Distribution

Yemen.

Figures

Fig. 18. Spathius austroarabicus Belokobylskij sp. nov., holotype, ♀ (RMNH). A. Habitus, lateral view. B. Head and mesosoma, dorsal view. C. Head and mesosoma, lateral view. D. Hind leg. E. Basal segments of antenna. F. Apical segments of antenna. G. Head, front view. H. Mesosoma and petiole, dorsal view.

Fig. 19. Spathius austroarabicus Belokobylskij sp. nov., holotype, ♀ (RMNH). A. Wings. B. Metasoma, dorsal view. C. Metasoma and ovipositor, lateral view.