Cheiloneurus omorus, 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 : 453-455

Cheiloneurus omorus sp.nov.

(Figs 1151-1156; Hab. E 165)

DIAGNOSIS. Female (length about 1.0- 1.1mm): body mostly orange, mesoscutum posteriorly, propodeum laterally and gaster partially brown, darker areas with a weak to moderate metallic sheen; mouth margin dark brown; temple with a very faint diagonal, brown streak; antenna (Fig. 1152) with scape mostly pale orange with ventral margin brown; pedicel pale orange with a longitudinal, dark brown streak; funicle mainly pale orange, some segments slightly dusky; clava dark brown; posterior half to two-thirds of mesoscutum with dense silvery setae; coxae white, mid coxa sometimes pale orange; legs mostly white to pale orange with brown areas; fore wing (Fig. 1155) mostly infuscate with basal cell almost completely hyaline, a small hyaline area at apex of venation and an opposite hyaline area on posterior wing margin, apex hyaline; head (Fig. 1153) about 5-5.4X as wide as frontovertex, in facial view about as broad as long, sometimes clearly broader than long, subcircular with genae converging and uniformly curved, slightly more curved inwards near mouth margin; frontovertex with one or two setae medially above scrobes; eye separated from scrobe by about 1.8-2X diameter of anterior ocellus, area between eye and scrobe completely smooth, scrobal margin rounded; interantennal prominence with about 15 inconspicuous setae and with a dorsal median ridge; mandible with one tooth and a broad, concave truncation, sometimes appearing tridentate; antenna (Fig. 1152) with scape about 3.1X as long as broad; funicle segments subquadrate to transverse; head width slightly greater than flagellum length; linear sensilla on F5-F6; clava 3-segmented, about as long as funicle; sensory area enlarged and forming an oblique truncation, extending about 0.4X along ventral margin; mesoscutum (Fig. 1151) anteriorly with fairly fine, longitudinally elongate, lineolate-reticulate sculpture; scutellum with a distinct, apical tuft of setae; wings fully developed; fore wing (Fig. 1155) about 2.4-2.6X as long as broad; parastigma slightly downcurved; costal cell naked dorsally or with one or two setae at apex, with a line of setae ventrally that is broadly interrupted above parastigma; area below proximal part of parastigma with up to 8 pale setae arranged in 1 or 2 lines; apices of postmarginal and stigmal veins connected by a naked hyaline area that curves a little way into disc; apical bristle of postmarginal vein about 0.6X as long as marginal vein; mid tibial spur very slightly longer than basitarsus; propodeum (Fig. 1151) with two or three setae adjacent to spiracle, side naked; syntergum about 0.9X as long as mid tibia; ovipositor (Fig. 1156) about 3.5-3.6X gonostylus or about 1.5X as long as mid tibia; exserted part of ovipositor about 0.3-0.5X as long as mid tibial spur. Male: unknown.

Female (holotype): length, including ovipositor, 1.05mm; excluding ovipositor, 1.00mm (CPD).

Head mostly pale orange; frontovertex with a weak blue, green and purple sheen, stronger in ocellar area; temple and upper gena with a weak brassy sheen, lower gena with a very weak brassy and purple sheen, area between eye and scrobe with a slightly stronger purple sheen; scrobal area with a weak brassy and purple sheen; lower face with a median, curved, brown line between toruli and mouth margin that meets mouth margin near base of mandible; temple with an extremely faint, diagonal pale brown streak from temple behind eye towards torulus; frontovertex clothed with inconspicuous, pale brown setae, a line of translucent setae between eye and scrobe; maxillary palpus white; antenna (Fig. 1152) with radicle pale orange, apex narrowly ringed orange-brown; scape pale orange, distinctly margined brown ventrally, more widely so internally towards base, upper margin weakly brown; pedicel mostly pale orange with a dark brown streak internally along its length; funicle segments largely pale orange, F1-F3 slightly dusky on sides, F6 slightly dusky internally, clava dark brown; pronotum mostly orange, neck and side above coxa brown; mesoscutum anteriorly orange, posterior half shining blue-green and green with slight purple reflections, behind this narrowly orange, posterior margin brown with a weak purple sheen, anterior half of mesoscutum clothed in relatively sparse golden brown to dark brown setae, posterior half clothed in relatively dense, translucent, silvery setae mixed with a few dark brown setae; tegula orange with apex orange-brown; axilla and scutellum orange, axilla clothed with brown setae, scutellum clothed anteriorly with golden brown setae, otherwise setae dark brown, subapical tuft black; metanotum slightly dusky pale orange; mesopleuron pale orange, slightly dusky posteriorly, anterior part with a very weak brassy sheen, posterior part with a weak purple sheen; fore coxa white; fore femur concolourous with coxa basally, apex pale orange with a dorsal brown streak, tibia and tarsus very pale orange, tibia with a brown dorsal streak; mid coxa white; mid leg otherwise similarly coloured to fore leg, except that femur has remnants of a narrow, brown, subapical ring and tibia has remnants of a narrow, brown, subbasal ring; hind coxa white, femur largely concolourous, but with a dorsal, brown streak internally and a partial brown, subapical streak ventrally, knee brown, tibia dirty white with an external brown streak and an incomplete subbasal brown ring, tarsus off-white, distally pale orange to brown; fore wing (Fig. 1155) mostly infuscate, hyaline towards base and at apex; submarginal vein pale yellow, venation otherwise pale brown; propodeum dusky pale orange, slightly darker on side and with a weak blue and purple sheen, 2 or 3 white setae near spiracle; gaster largely pale orange to orange-brown, apex of syntergum and apex of outer plate of ovipositor pale brown, Gt1 dark brown dorsally, Gt2-Gt4 dark brown medially, Gt5 similar but paler, Gt1 with a distinct metallic green sheen laterally, otherwise gaster generally with a mixed coppery, purple, green, blue and brassy sheen that is weakest on paler areas; gonostylus very pale orange, almost white.

Head (Fig. 1153) about 5X as wide as frontovertex, in profile about 1.6X as high as deep, anteriorly quite straight below top of scrobes, interantennal prominence hardly protuberant level with torulus; occipital margin sharp, not carinate; ocelli forming an angle of about 50°; frontovertex quite shiny, with shallow, fairly regular, polygonally reticulate sculpture of mesh slightly smaller than diameter of eye facet; area between eye and scrobe nearly 2X as wide as diameter of anterior ocellus, smooth; scrobes shallow, more or less Λ-shaped, not sharply margined; interantennal prominence with similar sculpture to frontovertex, dorsally with a strong, carinate, median ridge that reaches frontovertex and separates scrobes; temple virtually smooth with very shallow, irregular, elongate sculpture, gena with slightly deeper, irregular, reticulate sculpture; antenna as in Fig. 1152; scape broadened and flattened, about 3.1X as long as broad; funicle with segments broader and larger distad, proximal segments subquadrate, distal segments transverse; clava broadened, about as long as funicle, sutures oblique, sensory area enlarged, extending ventrally about 0.4X along clava, giving it an obliquely truncate appearance; eye reaching occipital margin, clothed with inconspicuous short setae, each a little shorter than diameter of facet; inner eye margins subparallel, diverging a little way above scrobes; malar sulcus absent; clypeal margin weakly concave medially; mandible with 1 tooth and a broad, concave truncation, more or less tridentate; apical segment of maxillary palpus not enlarged, hardly longer than radicle. Relative measurements: HW 52, HH 50, FV 10.5, POL 4, OOL 0, OCL 3, AOL 7.5, EL 33, EW 27, MS 23, SL 25, SW 8.

Thorax (Fig. 1151) with irregular, polygonally reticulate sculpture on pronotum that is of similar depth to that on frontovertex; mesoscutum with polygonally reticulate sculpture in posterior half that is a little deeper than that on frontovertex, anterior half with fairly fine, longitudinally elongate, lineolate-reticulate sculpture; axilla mostly with fairly regular, polygonally reticulate sculpture that is conspicuously deeper and coarser than that on frontovertex, scutellum with longitudinally striate-reticulate sculpture that is similar to that on anterior part of mesoscutum; visible part of mesoscutum about 1.9X as broad as long; scutellum about 1.1X as long as 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 1154, 1155; costal cell dorsally with 1 or 2 at apex; apices of postmarginal and stigmal veins connected by a distinct, naked, hyaline streak (Fig. 1154); propodeum (Fig. 1151) with side completely smooth, medially about 0.16X as long as scutellum and with very shallow, irregular sculpture, virtually smooth. Relative measurements: FWL 47.5, FWW 19; HWL 28.5, HWW 7.

Gaster with hypopygium reaching about half-way to apex; syntergum about 0.9X as long as mid tibia, with apex weakly angular; ovipositor slightly exserted, the exserted part about one-third as long as mid tibial spur or about one-tenth mid tibia.

Paratype. Funicle with linear sensilla present only on F5-F6; gaster without “gland-like” structures on Gt1 or Gt5; ovipositor Fig. 1156. Relative measurements: OL 38.5, GL 11 [MT 25].

Variation. Females vary in overall length from 0.95-1.08mm, F6 may be almost completely pale brown, the posterior half to two-thirds of the mesoscutum may have dense silvery setae, the head is about 5-5.4X as wide as the frontovertex and in facial view may be clearly broader than long, the eye is separated from scrobe by about 1.8-2X diameter of the anterior ocellus, the mandible may appear tridentate, the fore wing varies from about 2.4-2.6X as long as broad, the costal cell is dorsally naked or with one or two apical setae at apex, the gonostylus is about 1.1- 1.4X as long as the mid tibial spur and the exserted part of ovipositor is about 0.3-0.5X as long as the mid tibial spur.

Male. Unknown.

DISTRIBUTION. Costa Rica.

HOSTS. Unknown.

MATERIAL EXAMINED.

Type material. Holotype E: COSTA RICA, Heredia, San Joaquin de Flores, LN 220900 519700, 1064m, #5487, 7.vi-2.ix.1995 (C. Viquez) . Paratypes: COSTA RICA, 2E, Guanacaste, Santa Rosa NP, Hacienda 2-C, 14.vi-8.vii.1986 and 16.v-6.vi.1987 (D. Janzen, I.D. Gauld); 1E , Guanacaste, PN Palo Verde , 10°21’N 85°21’W, 20m, 21.iii.2013 (J.S. Noyes); 1E , Heredia, Santo Domingo, INBio Parque , LN 526250 217400, 1100m, iii.2002 ((J.A. Azofeifa, J.S. Noyes). Holotype in MZUCR, paratypes in NHMUK and MZUCR.

COMMENTS. Of the Costa Rica species, Cheiloneurus omorus is most similar to janzeni but differs in the females being smaller, only about 1.1mm long, lacking a conspicuous diagonal brown streak on temple and gena, having F6 conspicuously paler than clava, the hind tibia distinctly marked with brown, head about 5X as wide as the frontovertex, the clava as long as the funicle, irregular, shallow sculpture on the temple and upper gena, the scrobal margin rounded below the eye and the eye separated from the scrobes by about 2X its own diameter. Females of janzeni are up to 1.5mm long, have a strong diagonal brown stripe on the temple and gena, F6 dark brown and concolourous with the clava, the hind tibia immaculate, the head about 8X as wide as the frontovertex, the clava about as long as F3-F6 combined, the temple and upper gena completely smooth, the scrobal margin sharp below the eye and the eye separated from the scrobe by about its own diameter. Cheiloneurus omorus is also very similar to inimicus Compere , a species that has been recorded from many parts of the New World as a hyperparasitoid of soft scales ( Hemiptera : Coccidae ). Both species have a similar general colouration and habitus and also have the scrobal margin rounded below the eye. As with nasica (see p. 439) it is possible that some records of inimicus are based on misidentifications of omorus . It differs from inimicus in having the mouth margin distinctly marked with brown, the scape slightly more than 3X as long as broad and the dark band on the posterior part of the mesoscutum is quite strongly metallic green, blue-green or blue. In inimicus the mouth margin is pale orange and the scape is about 2.6-2.7X as long as broad and the band on the mesoscutum has only weak dark blue reflections.

See also comments under cero (p. 415), finator (p. 417), lexovus (p. 431) and amethes (p. 450).