Cheiloneurus exeres, 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 : 241-243

Cheiloneurus exeres sp.nov.

( Figs 601-603; Hab. E 91)

DIAGNOSIS. Female (length about 1.9-2.4mm): body generally dark brown to black with a weak to moderate metallic sheen; axillae and scutellum orange; antenna ( Fig. 602) with scape externally pale orange, dark brown internally with apex pale orange; pedicel mostly pale orange, dorsally dark brown proximally; funicle pale orange, proximally slightly dusky; clava dark brown; mesoscutum with silvery setae; coxae white; hind tibiae with a broad, dark brown, subbasal band, legs otherwise yellowish with some dark brown markings; fore wing ( Fig. 601) largely hyaline but weakly infuscate below marginal and stigmal veins and with a weak, infuscate median streak in apical half; head about 3.7X as wide as frontovertex, in facial view very slightly broader than long, subcircular, genae converging, moderately and evenly curved; frontovertex naked medially below anterior ocellus, but with about 5-10 setae medially immediately above scrobes; area between eye and scrobe about as 2X as wide as diameter of anterior ocellus, with shallow sculpture, scrobal margin rounded; interantennal prominence dorsally rounded with only a few long setae; mandible with two long, sharp lower teeth and a shorter, sharp, upper tooth; antenna ( Fig. 602) with scape about 3.5X as long as broad; funicle with F1 slightly longer than broad, remaining segments subquadrate; head width slightly less than length of flagellum; linear sensilla on F4-F6; clava 3-segmented, slightly longer than F3-F6 combined, sensory area large and forming an oblique truncation, extending about 0.4X along ventral margin; mesoscutum with polygonally reticulate sculpture; scutellum with a distinct, apical tuft of setae; wings fully developed; fore wing about 2.4-2.5X as long as broad; parastigma very weakly curved downwards; costal cell dorsally with 3 to 7 setae at apex and a single, complete line of setae ventrally; area below proximal part of parastigma with a group of about 15 setae; apices of postmarginal and stigmal veins not connected by a naked hyaline area; apical bristle of postmarginal vein about 0.4X as long as marginal vein; mid tibial spur about as long as basitarsus; propodeum with about 40 setae around each spiracle, side naked; syntergum about as long as mid tibia; ovipositor about 3.3X gonostylus or 1.7X mid tibia; gonostylus about 1.4X as long as mid tibial spur; exserted part of ovipositor about 0.4X as long as mid tibial spur. Male: unknown.

Female (holotype): length, including ovipositor, 1.97mm; excluding ovipositor, 1.87mm (CPD).

Head black with a weak blue and purple sheen on frontovertex, more strongly blue in ocellar area; occiput dull dark green; scrobal area mostly purple with some dark blue reflections especially on scrobes and interantennal prominence with a broad, purple band between toruli; mouth margin purple, above this metallic blue and blue-green; temple adjacent to eye margin brassy, green and coppery; gena duller and more distinctly purple and coppery; frontovertex with inconspicuous dark brown setae; antenna ( Fig. 602) with radicle dark brown; scape externally mostly pale orange margined dark brown except at apex, internally mostly dark brown with apical one-third pale orange; pedicel mostly pale orange, basal half or so dark brown dorsally; funicle pale orange, F1-F3 slightly dusky; clava dark brown; thorax mostly dark brown to black, axillae and scutellum orange; pronotum mainly dull purple-brown, posterior margin coppery; mesoscutum with a distinct metallic blue sheen with green reflections, slightly coppery anteriorly, posterior margin coppery purple, setae uniform and silvery, dark brown immediately behind posterior margin of pronotum; tegula dark brown; each axilla narrowly bordered brown posteriorly; scutellum matt, brown medially at apex, clothed anteriorly with pale brown setae, posteriorly with dark brown setae; metanotum with a slight purple sheen; mesopleuron in posterior half with a coppery-purple and brassy sheen, anterior half mixed blue, dark green, coppery and brassy, these narrowly separated by a coppery, dark blue and violet sheen; fore coxa white; fore femur white, pale orange distally, fore tibia pale orange with a small brown, subbasal spot; mid coxa white; mid femur pale yellow, pale orange towards apex and with a diffuse, subapical, brown spot, tibia pale orange with a diffuse, brown, subbasal spot; hind coxa white; hind femur white, pale brown apically, tibia mostly pale orange with an incomplete, brown, subbasal ring; tarsi pale orange-brown, pretarsi slightly dusky; fore wing ( Fig. 601) largely hyaline, weakly infuscate immediately below marginal and stigmal veins and along anterior part of linea calva, and with a weakly infuscate, median streak distad of pale brown venation; propodeum dark purple-brown; sides metallic green with a few conspicuous silvery setae in spiracular area; gaster dark purple-brown, dorsum slightly coppery, mixed purple and brassy, sides and outer plate of ovipositor mixed metallic green, blue, coppery and brassy; gonostylus dark brown, extreme apex pale orange.

Head about 3.7X as wide as frontovertex, not subtriangular in profile, anteriorly more or less evenly rounded in profile; occipital margin carinate, occiput without a median groove above foramen; ocelli forming an angle of about 65°; frontovertex slightly shiny, with conspicuous reticulate sculpture of mesh size generally very slightly smaller than diameter of eye facet; scrobal area and mouth margin with shallower sculpture; area immediately below eye almost completely smooth; gena and temple with more elongate sculpture of larger mesh; scrobes shallow, meeting dorsally, dorsal and lateral margins weakly rounded; antenna as in Fig. 602; scape hardly broadened and flattened, about 3.5X as long as broad; F1 a little longer than broad, F2-F3 quadrate; F4-F6 slightly longer than broad; clava hardly broadened, almost as long as F2-F6 combined; only outer suture noticeably oblique, sensory area enlarged, extending about one-third along clava ventrally and giving it an obliquely truncate appearance; eye not quite reaching occipital margin, separated by slightly less than diameter of facet, clothed with fairly conspicuous setae, each very slightly longer than diameter of facet; inner eye margins slightly converging anteriorly; malar sulcus absent; mandible with two, relatively long, acute, lower teeth, and a short, upper tooth. Relative measurements: HW 75.5, HH 74, FV 20.5, OD 5.5, POL 10, OOL 2, OCL 7, AOL 11, EL 47, EW 38, MS 31, SL 44, SW 12.5.

Thorax with shallow, irregular, polygonally reticulate sculpture on pronotum, generally of mesh size subequal to diameter of facet; sculpture on mesoscutum generally of similar depth to that on pronotum, but more regular and of smaller mesh; sculpture on axilla similar to that on mesoscutum, but slightly deeper; scutellum with conspicuously deeper, polygonally reticulate sculpture, more elongate on sides; extreme apex and sides completely smooth and shiny; visible part of mesoscutum about 2X as broad as long; scutellum about as long as broad, with a distinct subapical tuft, setae about 0.4X as long as scutellum; hind femur about 4.8X as long as broad; fore wing with venation and setation as in Figs 601, 603; costal cell with 3 setae dorsally at apex; no naked streak present between apices of postmarginal and stigmal veins ( Fig. 603); propodeum with moderately dense setae in spiracular area, side naked, medially about 0.1X as long as scutellum and with some shallow polygonally reticulate sculpture. Relative measurements: FWL 106, FWW 42; HWL 85.5, HWW 22.

Gaster with hypopygium reaching about half-way to apex; syntergum hardly longer than mid tibia, with apex acute; ovipositor slightly exserted, the exserted part about 0.4X as long as mid tibial spur.

Paratype. Funicle with linear sensilla present only on F4-F6; gaster without “gland-like” structures on TI or TV. Relative measurements: OL 83, GL 25.5 [MT 50].

Variation. Females vary in overall length from 1.94-2.39mm, otherwise very little in material examined, except that the ocellar angle may be only about 50°, the legs may be darker than in holotype with brown areas of the legs more extensive and the fore wing may vary from 2.4-2.5X as long as broad.

Male. Unknown.

DISTRIBUTION. Costa Rica.

HOSTS. Unknown.

MATERIAL EXAMINED.

Type material. Holotype E: COSTA RICA, San José, Cerro de la Muerte , 19km S, 3km W Empalme, 9°39’N 832’W, 2600m, iv-vii.1992 (P. Hanson, C. Godoy) . Paratypes: COSTA RICA, 1E, San José, Carret. Interamer., Villa Mills, 3000m, i-ii.1989 (P. Hanson); 2E, San José, Hwy 2, km 95, 9°36’N 83°44’W, 3200m, 3.iv.1986 (L. Masner, H. Goulet); 4E , Alajuela, Volcán Poas NP, 2500m, 6-28.vi.1996 (S. & J. Peck) . Holotype in MZUCR, paratypes NHMUK, CNC .

COMMENTS. Cheiloneurus exeres is similar to fidenas , lamus and miklo in that all four species all have a distinct median, longitudinal, infuscate streak in the apical half of the fore wing. Apart from the colour of the scutellum, exeres can be separated the other species by having the scape less than 4X as long as broad, whereas in the other species it is more than 4X as long as broad. It can also be separated from lamus and miklo by having the ovipositor more than 3X as long as the gonostylus, whereas in lamus and miklo it is less than 3X as long.

See also comments under herndonia (p. 240).