Elaxis, Noyes, 2023

Noyes, John Stuart, 2023, ENCYRTIDAE OF COSTA RICA (HYMENOPTERA: CHALCIDOIDEA), 4 Subfamily Encyrtinae: tribes Arrhenophagini, Habrolepidini, Cerapterocerini, Cheiloneurini, Trechnitini, Cercobelini, Polaszekiini, Protyndarichoidini, Gahaniellini and Syrphophagini (part), mainly primary parasitoids and hyperparasitoids of Coccoidea and Psylloidea (Hemiptera), Taxonomic Monographs on Neotropical Hymenoptera (Oxford, England) 2 (11), pp. 1-921 : 710-711

Genus ELAXIS gen.nov.

Type species: Elaxis auster sp.nov. Gender: feminine.

Female. Length about 1.2mm.

Body robust, generally dark with a weak to moderate metallic sheen; funicle with pale and dark segments; dorsum of thorax with dark setae; legs generally dark with pale areas; wings hyaline, weakly infuscate adjacent to marginal vein; propodeum dark with a weak metallic sheen, side more strongly metallic, gaster dark brown with a metallic sheen.

Head in profile about 1.7X as high as deep, anteriorly fairly evenly curved from occipital margin to top of scrobes, more curved at top of scrobes and virtually straight to mouth margin, interantennal prominence slightly protuberant; occipital margin carinate; frontovertex about one-third head width and with regular, polygonally reticulate sculpture and distinct piliferous punctures; ocelli forming nearly a right angle; temple and gena with shallow, longitudinally elongate, polygonally reticulate sculpture; eye virtually reaching occipital margin, with fairly inconspicuous setae, scrobes shallow, ∩-shaped; antenna attached near mouth margin, well below lower eye margin; scape strongly broadened and flattened, less than 2X as long as broad, about 0.6X as long as head width; all funicle segments transverse, gradually becoming broader distally, linear sensilla only on distal funicle segments; clava longer than funicle, 3-segmented, sutures strongly oblique, sensory area enlarged, extending along ventral surface of clava giving it a strongly obliquely truncate appearance; malar sulcus absent; mouth about 0.4X head width, margin medially slightly concave; mandible tridentate, upper tooth slightly obliquely truncate; palp formula 4-3.

Thorax with pronotum very short; mesoscutum without notaular lines; scutellum convex, mostly with longitudinally elongate sculpture that is conspicuously deeper than sculpture on mesoscutum, extreme sides and apex completely smooth; mid tibial spur slightly longer than basitarsus; fore wing fully developed; about 2.4X as long as broad; costal cell with only 1 line of setae ventrally and about 6 apical setae dorsally; submarginal vein with an apical hyaline break; marginal vein about 2-3X as long as broad, a little longer than stigmal vein which is a little longer than postmarginal vein; linea calva open; filum spinosum present, consisting of about 5 stouter peg-like setae; posterior margin of mesopleuron not reaching level with posterior margin of propodeum, falling short by distance about equivalent to diameter of propodeal spiracle; propodeum short, virtually smooth medially and without a posterolateral projection behind spiracle; about 10 setae near spiracle, partly extending down side to hind coxa.

Gaster with hypopygium not reaching apex; paratergites absent; syntergum shorter than mid tibia, apex angular; ovipositor more or less hidden; ovipositor longer than mid tibia, basal part of second valvifer broadly C-shaped; second valvifer without any subapical setae; hypopygium transverse, subrectangular, anterior margin very shallowly biconcave with anterior lateral projections very short, posterior margin shallowly biconvex.

Male. Unknown.

DISTRIBUTION. Known only from Costa Rica, but likely to be more widespread in the Neotropics.

HOSTS. Unknown.

COMMENTS. Elaxis is probably close to Dalek and similar genera (e.g. Hebynthus , Alkonia , Raquanus , Polaszekius , etc.) that may form a monophyletic group, along with Caldencyrtus (see comments under Alkonia , p. 708). It can be separated from other genera in the group by having the scape less than 3X as long as broad, the funicle with dark and light segments and the clava longer than the funicle with a strongly obliquely truncate apex.