Cheiloneurus argos, 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 : 344-346

Cheiloneurus argos sp.nov.

( Figs 859-865)

DIAGNOSIS. Female (length about 1.6mm): head and thorax mostly orange to orange-brown, most of mesoscutum, propodeum and gaster dark brown, darker areas with a weak to moderate metallic sheen; antenna ( Fig. 859) with scape mostly white, margins largely brown; pedicel mostly dark brown; flagellum dark brown; mesoscutum with dense silvery setae in posterior three-quarters; fore and hind coxae white, mid coxa brown dorsally, pale orange ventrally; legs mostly white to pale orange with dark brown areas on tibiae and femora; fore wing ( Fig. 862) mostly infuscate, basal cell mostly hyaline, a small hyaline area at apex of venation, a pale area opposite; head ( Fig. 860) about 4.2X as wide as frontovertex, in facial view very clearly broader than long, subcircular, genae evenly and weakly curved, converging, slightly more curved inwards near mouth; frontovertex with four setae medially between anterior ocellus and scrobes; eye separated from scrobe by about diameter of anterior ocellus, area between eye and scrobe smooth and shiny; scrobes deep, sharply margined, weakly so medially, carinate below eye, interantennal prominence with about 35 conspicuous setae, dorsally rounded, without a median ridge; mandible tridentate; antenna with scape ( Fig. 859) about 2.7X as long as broad; funicle with F1-F4 slightly longer than broad, F5-F6 quadrate or transverse; clava 3-segmented, about as long as F3-F6 combined; sensory area enlarged, extending ventrally about 0.2X length of clava, apex obliquely truncate; head width clearly less than flagellum length; mesoscutum ( Fig. 861) anteriorly with fairly regular, fine, elongate, lineolate sculpture, posteriorly with more regular, polygonally reticulate sculpture; scutellum with a distinct, apical tuft of setae; wings fully developed, fore wing ( Fig. 862) about 2.8X as long as broad; parastigma downcurved; costal cell dorsally naked or with a single seta at apex, ventrally with an almost complete line of setae which is narrowly interrupted above parastigma; area below proximal part of parastigma with a group of about 20 uniform, fine setae; apices of postmarginal and stigmal veins connected by a naked hyaline area that continues someway into disc ( Fig. 864); apical bristle of postmarginal vein about 0.6X as long as marginal vein; mid tibial spur slightly longer than basitarsus; propodeum with about five inconspicuous setae adjacent to spiracle, side naked; syntergum about 1.1X as long as mid tibia with apex acute; ovipositor ( Fig. 863) about 3.3X gonostylus or about 1.8X as long as mid tibia; gonostylus about 1.4X as long mid tibial spur; exserted part of ovipositor about 0.8X as long as mid tibial spur. Male: unknown.

Female (holotype): length, including ovipositor, 1.60mm; excluding ovipositor, 1.44mm ( CPD) .

Head generally orange-brown; occiput, scrobes, lower part of interantennal prominence and posterior part of gena pale orange; mouth margin pale orange; occiput with a dark brown triangular mark above foramen; area between occipital margin and anterior ocellus with a violet sheen, laterally metallic blue and blue-green; frontovertex in front of anterior ocellus with a moderate blue-green and slight purple sheen; area between eye and scrobe shining metallic green, blue-green and purple, bordered coppery laterally; temple and upper gena with a metallic green sheen, mixed coppery posteriorly and ventrally; lower gena with a weaker purple, coppery and brassy sheen; upper interantennal prominence with a coppery purple sheen, lower part of interantennal prominence with a weak brassy and purple sheen; frontovertex clothed with inconspicuous, pale brown setae, these continued as a line below eye and scattered on gena; interantennal prominence with relatively dense, conspicuous, translucent silvery setae; antenna ( Fig. 859) with radicle pale orange proximally, but mostly dark brown; scape largely white but with ventral margin broadly dark brown to about 0.75X along its length, base completely dark brown, dorsal margin orange with apex dark brown; pedicel mainly dark brown, but paler orange-brown dorsally; flagellum dark brown; maxillary palpus white, terminal segment very pale orange; pronotum pale orange with weak coppery and brassy reflections, neck brown; propleuron pale orange, dark brown in front of coxa; prosternum dark brown, pale orange posteriorly; mesoscutum mostly black with a weak, but distinct dark, metallic blue and purple sheen, anterior part (normally covered by pronotum) orange with slight coppery reflections; mesoscutum mainly clothed in conspicuous, translucent silvery setae, anterior setae slightly less dense and golden brown to dark brown setae; tegula slightly dusky pale orange with apex dark orange-brown with a weak purple sheen; axilla orange with weak purple reflections and with a few black and golden brown setae; scutellum orange with weak purple reflections, with golden brown setae, subapical tuft black; metanotum dark brown; mesopleuron dark orange-brown, with a moderate coppery, blue, green, brassy and purple sheen; mesosternum dark brown; fore coxa white; fore femur mostly white, apex and margins dark brown, tibia white at extreme base, broadly dark brown medially, apex slightly dusky pale orange, tarsus slightly dusky pale orange; mid coxa brown dorsally, pale orange ventrally; mid femur white, apical two-fifths brown with an incomplete subapical dark brown ring on inner surface and dorsal margin, tibia dark brown at extreme base, white subbasally otherwise very pale orange with an incomplete, subbasal dark brown ring continued as a dark brown streak externally for most of length of tibia, spur and tarsus pale orange; hind coxa white, hind femur dark brown, tibia white at base, apex pale orange, otherwise dark brown, tarsus pale orange; fore wing ( Fig. 862) mostly infuscate, largely hyaline towards base, submarginal vein pale orange otherwise venation brown; propodeum dark brown, medially with a coppery and brassy sheen, laterally with coppery purple and metallic green patches, side relatively dull blue-green, blue and purple, about 5 silvery setae in a line outside spiracle; gaster mainly dark brown with a slight brassy and purple sheen, Gt1 and Gt2 dorsally mixed relatively strongly coppery, green, purple and blue, sides of Gt3-Gt5 with a relatively strong green and blue-green sheen with coppery and purple reflections, sternites with coppery, blue, green, purple and brassy reflections; gonostylus very pale orange, apex slightly dusky.

Head ( Fig. 860) in facial view about 4.2X as wide as frontovertex with gena rounded and converging, in profile about 1.4X as high as deep, frontovertex slightly angled level with posterior ocelli, then weakly and evenly curved to top of scrobes, strongly angled at top of scrobes towards mouth margin, with interantennal prominence slightly protuberant; occipital margin sharp, weakly carinate; a short, shallow, groove present on eye margin behind ocellus; ocelli forming an angle of about 65°; frontovertex with shallow, polygonally reticulate sculpture of mesh size generally subequal to, or smaller than, diameter of eye facet; area immediately above scrobes with relatively deep, coarse, transversely elongate, polygonally reticulate to imbricate-reticulate sculpture, area outside this between eye and scrobe completely smooth and shiny; temple and upper gena very shiny with shallow, longitudinally elongate imbricate-reticulate to strigose sculpture, lower gena with similar sculpture to that on temple but less shiny; scrobes smooth; interantennal prominence virtually smooth but with fine, shallow, polygonally reticulate sculpture; narrowest part between eye and scrobal margin about as wide as diameter of anterior ocellus, scrobes deep, meeting dorsally, sharply margined, weakly so dorsally, but carinate below eye, very broadly ∩-shaped, interantennal prominence dorsally broadly rounded, without a median ridge; antenna as in Fig. 859; scape broadened and flattened, broadest about middle or slightly above, about 2.7X as long as broad; funicle with F1-F4 very slightly longer than broad, F5 quadrate, F6 transverse, segments clearly larger and wider distally, linear sensilla present only on F4-F6; clava hardly broadened, about as long as F3-F6 combined, sensory area slightly enlarged, extending about 0.2X along ventral surface, giving it a weakly oblique, truncate appearance; eye not quite reaching occipital margin, separated by about 1.5X diameter of facet, with extremely short, inconspicuous setae, each much shorter than diameter of facet; inner eye margins weakly converging in front of anterior ocellus, narrowest part of frontovertex a little nearer scrobes than anterior ocellus; malar sulcus absent; clypeal margin medially weakly emarginate; mandible with 3 acute teeth, upper tooth slightly shorter; apical segment of maxillary palpus not enlarged, hardly longer than radicle. Relative measurements: HW 80, HH 73, FV 19, POL 10, OOL 0.5, OCL 10.5, AOL 10.5, EL 55, EW 44, MS 32, SL 37, SW 13.5.

Thorax ( Fig. 861) with pronotum hardly exposed behind head and about 0.5X as long as mesoscutum; pronotum with shallow, imbricate-reticulate to polygonally reticulate sculpture that is of similar depth to that in ocellar area; mesoscutum in anterior half with fairly regular, fine, obliquely, elongate, lineolate sculpture that is clearly a little deeper than that on pronotum, posterior half strongly contrasting with sculpture tending more towards vermiculate-reticulate and polygonally reticulate; axilla and scutellum with polygonally reticulate sculpture that is slightly coarser than that on mesoscutum but of similar depth, more longitudinally elongate laterally on scutellum; visible part of mesoscutum about 2X as broad as long; scutellum hardly longer than broad, with a distinct subapical tuft, setae mostly about 0.7X as long as scutellum; hind femur about 4.3X as long as broad; fore wing with venation and setation as in Figs 862, 864; costal cell naked dorsally at apex; apices of postmarginal and stigmal veins connected by a distinct, naked, hyaline streak ( Fig. 864); mid tibia without an external carina; propodeum ( Fig. 861) medially about 0.19X as long as scutellum and smooth. Relative measurements: FWL 105.5, FWW 37.5; HWL 94, HWW 21.

Gaster without “gland-like” structures on Gt1 or Gt5; hypopygium ( Fig. 865) reaching about 0.4X to apex; syntergum about as long as mid tibia, with apex acute; ovipositor ( Fig. 863) exserted, the exserted part about 0.8X as long as mid tibial spur or 0.3X as long as mid tibia. Relative measurements: OL 68, GL 17.5 [MT 37.5].

Variation. Only holotype examined.

Male. Unknown.

DISTRIBUTION. Costa Rica.

HOSTS. Unknown.

MATERIAL EXAMINED.

Type material. Holotype E: COSTA RICA, Alajuela, RF Arenal, Stor Colada , LN 269900 456750, 600m, #74102, v-vi.2000 (G. Carballo) . Holotype in NHMUK .

COMMENTS. Cheiloneurus argos is very similar to feritas and, apart from the characters given in the key, argos can be separated from feritas by having F3 and F4 both very slightly longer than broad, the posterior ocellus midway between occipital margin and anterior ocellus and a group of about 20 uniform, fine setae below the parastigma. In feritas F3 is quadrate and F4 distinctly transverse, the posterior ocelli are slightly closer to the occipital margin than to the anterior ocellus and there is a group of about 40 non-uniform setae below the parastigma. In addition, argos has the mid femur proximally white with apical two-fifths brown and the hind femur dark brown, whereas in feritas the mid femur is white with an incomplete, subapical dark brown ring and the hind femur is white basally and distally dark brown.

See also comments under feritas (p. 349).