Ludesia, 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 : 178-179

Genus LUDESIA gen.nov.

Type species: Ludesia hemera sp.nov. Gender feminine.

Female. Overall length about 1.2-1.9mm.

Antenna with clava white, funicle mostly dark brown; maxillary palpus white; mesopleuron partially white; all coxae white, mid coxa sometimes partially brown; fore wing remnant with base and apical one-third or so infuscate.

Head about 4-6X as wide as frontovertex; occipital margin narrowly rounded; eyes conspicuously hairy with dense setae at least about as long as diameter of facet; scrobes moderately deep, narrowly ∩-shaped, meeting, dorsally very smooth but with extremely shallow sculpture towards outer margins, sharply margined dorsally and laterally, but not carinate; interantennal prominence without median ridge, narrowly rounded dorsally, with shallow, regular, polygonally reticulate sculpture; scape slightly broadened and flattened, about 3-3.5X as long as broad; funicle 6-segmented, segments subcylindrical, becoming progressively shorter and broader distally; clava 3-segmented, apex rounded; clypeus deeply emarginate, about one-third as deep as length of torulus; mandible with two acute lower teeth and a fairly broad truncation, appearing almost tridentate; palp formula 4-3, apical segment of maxillary palpus not enlarged, hardly longer than radicle.

Thorax with pronotum medially about 0.5X as long as mesoscutum; pronotum, mesoscutum and scutellum with fairly uniformly coarse, polygonally reticulate sculpture; mesoscutum without notaular lines; scutellum with relatively dense evenly distributed, conspicuous setae, scutellar tuft absent, apical pair of setae about as long as others on scutellum; mid tibial spur about 0.7X as long as basitarsus; wings shortened, fore wing not reaching TII of gaster, about 3.5X as long a broad, apex oblique; mesopleuron posteriorly enlarged, reaching well past posterior margin of propodeum and touching base of gaster; propodeum with conspicuous course, reticulate sculpture around spiracle.

Gaster with outer plates of ovipositor free, paratergites absent; ovipositor hidden or hardly exserted, gonostylus articulated, second valvifer with 2 or 3 subapical setae; hypopygium subrectangular, transverse, about 2.5X as broad as long.

Male. Overall length about 1.0- 1.4mm.

Antenna filiform; funicle 6-segmented, clothed with setae that are mostly about half as long as diameter of segments, linear sensilla numerous on all segments and very prominent; clava 3-segmented; fore wing fully developed, about 2.5X as long as broad; weakly infuscate; costal cell with about 6 setae dorsally at apex; marginal vein about 5X as long as broad, postmarginal vein about half as long a stigmal vein, stigmal vein forming an angle of about 55-65°with anterior margin of wing and about 0.7X as long as marginal vein; linear calva entire; filum spinosum present, represented by 3 or 4 pegs; phallobase with each digitus about 2X as long as broad, with an apical tooth and small outer apical seta, paramere reaching nearly half way towards apex of digitus, with an apical setae, cuspis seta present; aedeagus about 8-9X as long as broad, about 0.4- 0.5X as long as mid tibia, with apex angular.

DISTRIBUTION. Neotropical.

HOSTS. Unknown, but probably primary parasitoids of scale insects ( Hemiptera : Coccoidea) associated with herbaceous vegetation.

COMMENTS. Females of Ludesia superficially looks close to several species of Cheiloneurus that may be brachypterous (e.g. tainus ), as well as brachypterous species of Diversinervus (e.g. cervantesi (Girault)) . This similarity would probably place Ludesia in the Cheiloneurini . This is supported by the posteriorly enlarged mesopleuron that extends well past the posterior margin of the propodeum, a character state frequently found in members of this tribe. Females can be distinguished from brachypterous species belonging to either group by the hairy eyes, conspicuously short mid tibial spur which is much shorter than the basitarsus, complete lack of a tuft of setae on the scutellum and the presence of rough, reticulate sculpture around the propodeal spiracle. They further differ from brachypterous species of Diversinervus by the complete lack of a frontofacial carina and the mandible having two acute teeth and an upper truncation, whereas all species of Diversinervus have a distinct frontofacial carina and three acute teeth in the mandible. On the other hand males can be easily distinguished by the 3-segmented clava and relatively large angle formed by the elongate stigmal vein with the anterior margin of the fore wing. The latter would suggest a closer relationship of Ludesia with Diversinervus and Anisophleps than with Cheiloneurus .

One species of the genus is known from Argentina, Ludesia semifacta ( De Santis, 1972) comb. nov. (from Ectroma ) and another, as yet undescribed, species from Brazil ( Bahia ) (NHMUK). The latter differs by having distinct reticulate sculpture on gastral tergites Gt1-Gt6 whereas in the three other known species the gastral tergites are smooth and shiny.