Cheiloneurus longisetaceus De Santis, 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 : 366-367

Cheiloneurus longisetaceus De Santis stat.rev.

( Figs 928-936; Hab. E 134)

Cheiloneurus longisetaceus De Santis 1939:334-336 . Holotype E, Argentina, MLP , image examined.

DIAGNOSIS. Female (length about 1.4-2.3mm): body almost completely dark brown with a weak to moderate metallic sheen. often with orange areas on the lower face, pronotum, axilla and scutellum; antenna ( Figs 930, 931) with scape mostly white with dorsal and ventral margins largely brown; pedicel and flagellum dark brown; posterior part of mesoscutum with evenly distributed translucent silvery setae; fore and hind coxae white, mid coxa orange-brown to dark brown; legs dark orange-brown to dark brown, mid legs paler; fore wing ( Fig. 933) mostly infuscate with basal cell mostly hyaline, a small hyaline area at apex of venation, a diffuse paler area opposite and apex with a small, slightly paler or hyaline area; head ( Fig. 928) about 6.1-6.9X as wide as frontovertex, in facial view from about as long as broad to clearly longer than broad, subquadrate, genae slightly curved but hardly converging, more strongly curved inwards near mouth; frontovertex naked medially between anterior ocellus and scrobes or sometimes with up to two setae; eye separated from scrobe by about diameter of anterior ocellus to nearly 1.5X diameter of anterior ocellus, area between eye and scrobe completely smooth; scrobes deep, sharply margined, carinate below eye; interantennal prominence with about 40-50 inconspicuous setae and dorsally broadly rounded without a median ridge; mandible virtually tridentate; antenna ( Fig. 930, 931) with scape about 4.0-4.5X as long as broad; F1-F4 longer than broad, F5-F6 quadrate or transverse, sometimes F4 quadrate; linear sensilla on F2-F6 or absent from F2 or even F3; clava 3-segmented, about as long as F4-F6 combined; sensory area enlarged, extending ventrally about 0.3-0.4X length of clava, apex obliquely truncate; head width slightly greater than funicle length, clearly less than flagellum length; mesoscutum ( Fig. 932) with fairly regular polygonally reticulate sculpture, very slightly more elongate and coarser anterolaterally; scutellum with a distinct, apical tuft of setae; wings fully developed, fore wing ( Fig. 933) about 2.6-2.8X as long as broad; parastigma slightly downcurved; costal cell dorsally naked or with one or two apical setae, ventrally with a line of setae in proximal 0.6X; area below proximal part of parastigma with a group of about 10-18 setae; apices of postmarginal and stigmal veins connected by a naked hyaline area that continues a little way into disc ( Fig. 929); apical bristle of postmarginal vein about 0.7-0.8X as long as marginal vein; mid tibial spur slightly longer than basitarsus; propodeum with up to four inconspicuous setae adjacent to spiracle, side naked; gaster without “gland-like” structures on Gt1 or Gt5; syntergum about 0.9X as long as mid tibia with apex broadly angular; hypopygium Fig. 936; ovipositor ( Figs 934, 935) about 3.6-4.2X gonostylus or about 1.3-1.6X as long as mid tibia; gonostylus about 0.9-1.0X as long mid tibial spur; exserted part of ovipositor about 0.5-1.2X as long as mid tibial spur. Male (length about 1.5mm): inadequately described by De Santis (1939), the characters given would not help distinguish males of this species from others of the genus.

DISTRIBUTION. Costa Rica, Argentina.

HOSTS. Unknown.

MATERIAL EXAMINED.

Type material: Holotype E (on slide): white label “D.A.G.I. Laboratorio de Entomologia ex Baradero capturado en Citrus E leg D.S./ I/1937 ”, red label “D.A.G.I. “D.A.G.[I.] 1967 Laboratorio Entomologia Cheiloneurus longisetaceus Holotipo det. De Santis”;

Non type material. COSTA RICA, 1E, Heredia, La Selva BS, 10°26’N 84°01’W, 50-150m, fog Carapa guianensis, FOT /02, 5.iii.1993 ( INBio / OET); 1E, Heredia, OTS La Selva, 10°26’N 84°01’W, canopy fog Virola koschayi, FVK /11, 4.ix.1993 ( INBio / OET); 2E, Heredia, OTS La Selva, 75m, 10°26’N 84°01’W, xii.1993 ( ALAS).1E, Heredia, La Selva BS, 10°26’N 84°01’W, FVK 32, 3.xi.1994; 1E, Heredia, OTS La Selva, FPM 23, 14.x.1994 ( ALAS); 1E, Puntarenas, Buenos Aires, 120m, viii-ix.1991 (P. Hanson); 1E, Puntarenas, Golfito, 20.iii.1990 (J.S. Noyes); 2E, Puntarenas, Golfito, RF Golfo Dulce, Est. Agujas, LS 526550 276750, 300m, 15.ii-15.iii.2001 and iii-iv.2001 (J. Azofeifa); 1E, Puntarenas, RF Golfo Dulce, 24km W Piedras Blancas, 200m, 8°46’N 83°24’W, ii.1992 (P. Hanson); 1E, Puntarenas, PN Corcovado, Los Patos, LS 517900 281600, 200m, 21.ii.2002 (J.A. Azofeifa). Material in MZUCR and NHMUK.

COMMENTS. Cheiloneurus longisetaceus was treated previously as a synonym of nigrescens Howard (1897) ( Noyes, 1979), but in light of the present study I now consider this synonymy to be incorrect. Cheiloneurus longisetaceus differs from nigrescens in a number of important characters, not least the difference in the colour of the hind coxa (dark brown in nigrescens , pale yellow in longisetaceus ) and mesoscutum (largely metallic dark blue in nigrescens , dark brown in longisetaceus ). Comparison of the Costa Rica specimens with the digital image of the holotype (slide-mounted and in poor condition) shows little difference except that F 3 in the holotype appears to be only about 1.4X as long as broad whereas in the Costa Rica material it is usually more than 1.5X as long as broad. The Costa Rica specimens are provisionally placed in longisetaceus pending direct comparison with freshly collected, topotypical material. As understood here, longisetaceus is separated from other species using the characters presented in the key.