Arabencyrtus Hayat

Hayat, Mohammad, Ahmad, Zubair & Khan, Farmanur Rehman, 2014, Encyrtidae (Hymenoptera: Chalcidoidea) from the Kingdom of Saudi Arabia, Zootaxa 3793 (1), pp. 1-59 : 10-12

5. Arabencyrtus Hayat , gen. nov.

( Figs 18–22 )

Type species Arabencyrtus qahtanii Hayat , sp. nov.

Female. Head dorsal 2.33× as broad as long; occipital margin sharp, slightly concave between eyes; frontovertex convexly merging with face, and 0.37× head width; head, in frontal view, slightly higher than broad ( Fig. 19 ); antennal torulus touching mouth margin; intertorular area flat; eye posteriorly separated from occipital margin by a distance about equal to diameter of anterior ocellus; eye bean-shaped, with posterior margin slightly concave; eye height 2.8× malar space. [Palps lost.] Mandible bidentate, teeth acute. Antennal formula, 1163 ( Fig. 18 ); scape cylindrical, more than 8× as long as broad and 1.92× as long as frontovertex width; pedicel as long as F1 and F2 combined; F1 shorter than F2; F1–F3 each longer than broad, F4–F6 each subquadrate to slightly broader than long (F6); clava 3-segmented, sutures oblique, and nearly as long as preceding four segments combined.

Mesosoma ( Fig. 21 ). Pronotum dorsally subtriangular, median length slightly less than median length of the visible part of mesoscutum, and 1.86× as broad as long; mesoscutum with very short, faint notaular lines overlapped by pronotal collar; axillae meeting; scutellum slightly longer than broad; propodeum large, median length one-third scutellum length, with spiracles small and rounded, and posterior margin medially concave (petiole located in this concavity); propodeum with two submedian ridges. Fore wing ( Fig. 20 ) infuscated, with basal third or so, except an oblique infuscated streak at base, and a cross band distal to venation, hyaline; costal cell narrow, not broader than width of submarginal vein, and bare in about distal two-thirds; discal setae in infuscated areas largely with blunt or rounded tips; linea calva basally closed by several lines of setae; the line of setae proximal to linea calva hardly extending half wing width at that point, otherwise linea calva open posteriorly; basal triangle with some hyaline setae, except the infuscated streak with black, blunt tipped setae; venation extending to 0.68× wing length; parastigma enlarged proximally, and 0.36× length of submarginal vein; marginal vein longest, about 2× as long as postmarginal vein which is about 1.35× as long as stigmal vein; stigmal vein curved and with 4 circular sensilla arranged in a straight line. Hind wing slightly more than 4.8× as long as broad. Legs unmodified; tarsal formula, 5–5–5.

Metasoma subequal in length to head and mesosoma combined; hypopygium prominent, boat-shaped, extending beyond apex of gaster; apical tergites of gaster modified as in some species of Allocerellus Silvestri ( Annecke & Mynhardt 1970a: figs 4, 13, 17, 24); TVII short, about 0.16× gaster length; TVI medially membranous, and with an elongate-oval plate medially extending anteriorly beneath TV and TIV ( Fig. 22 ); paratergites short and broad; ovipositor with second valvifer in about apical fourth slightly enlarged, and then continues in apical fifth as a narrow ribbon-like process ( Fig. 22 ). [It is possible that the slightly enlarged part with the ribbon-like process represents the third valvula (= gonostylus).]

Male. Unknown.

Comments. The new genus belongs to the subfamily Tetracneminae and tribe Tetracnemini. It differs from all the genera of the Tetracnemini ( Prinsloo & Annecke 1979; Noyes & Hayat 1984,1994; Trjapitzin 1989; Noyes et al. 1997; Hayat 2006) by the following combination of characters: head, in frontal view, higher than broad; malar space nearly straight; scrobes absent; antennal torulus touching mouth margin; mesosoma with the visible part of pronotum subtriangular, less than 2× as broad as long, and only slightly shorter than the mesoscutum; mesoscutum with short notaular lines indicated anteriorly; propodeum large, its median length one-third the median length of the scutellum; fore wing with costal cell narrow, its width about equal to width of the submarginal vein; marginal vein longer than postmarginal vein, the latter longer than the stigmal vein; stigmal vein curved and with 4 circular sensilla arranged in about a straight line; discal setae in infuscated areas dark with blunt or rounded tips; third valvula fused with the second valvifer and with a ribbon-like process; and in the morphology of the apical tergites of the gaster. In this latter character, the new genus is similar to some species of the genus Allocerellus Silvestri (1915a) , a genus described from a male, but later 11 species were described from South Africa, based on females and males, by Annecke & Mynhardt (1970a) and Prinsloo (1995). However, these authors did not give the median lengths of the propodeum and the scutellum, and did not illustrate the second valvifer and gonostylus (= third valvula). The characters differentiating the new genus from Allocerellus are tabulated below.

It may be noted that some of the character states of the new genus may prove to be autapomorphic. It is, however, not possible to indicate the relationship of the new genus without a phylogenetic analysis of the morphological characters in the genera of the Tetracneminae .

Etymology. The generic name is derived from the name of the country, Saudi Arabia + encyrtus .

Allocerellus Arabencyrtus 1. Head, in frontal view, at most as high as broad, generally Head, in frontal view, higher than broad. broader than high.

2. Frontovertex width, at level of anterior ocellus, at least Frontovertex width, at level of anterior ocellus, less than 0.4× 0.5× head width. head width.

3. Scrobes present, inverted V-shaped. Scrobes absent.

4. Antennal torulus situated above mouth margin. Antennal torulus touching mouth margin. 5. Antennal clava, in species with a 3-segmented clava, with Antennal clava with the two sutures oblique, the second sutures at most slightly oblique. suture strongly convergent towards the first suture. 6. Visible part of pronotum transverse, several times broader Visible part of pronotum subtriangular, less than 2× as broad than median length. as median length.

7. Fore wing hyaline, with discal setae fine and normal, not Fore wing infuscate with basal third, except for an oblique with blunt or rounded tips. infuscate streak at base, and a band adjacent to distal veins, hyaline; discal setae in the infuscate areas dark with blunt or rounded tips.

8. Fore wing with costal cell large, width at least 3× the width Fore wing with costal cell narrow, not broader than width of of the submarginal vein. the submarginal vein.

9. Fore wing with linea calva broad, closed basally by 1 to 3 Fore wing with linea calva narrow, closed basally by several lines of setae. lines of setae.

10. Fore wing with marginal vein at most as long as Fore wing with marginal vein about 2× as long as postmarginal vein, generally shorter. postmarginal vein.

Figures

FIGURES 18 – 22. Arabencyrtus qahtanii Hayat, gen. et sp. nov. Female: 18, antenna, with clava enlarged; 19, head, frontal view; 20, fore wing, with veins enlarged; 21, mesosoma; 22, apical tergites of gaster with ovipositor, with apical part of second valvifer enlarged, arrow points to the third valvula and its posterior ribbon-like extension. pr = paratergite.