Cheiloneurus oshtan, 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 : 314-316

Cheiloneurus oshtan sp.nov.

( Figs 778-784; Hab. E 115)

DIAGNOSIS. Female (length about 1.4-1.8mm): body almost completely dark brown with a weak to moderate metallic sheen; antenna ( Fig. 781) with scape mostly white with dorsal and ventral margins largely brown; pedicel and flagellum dark brown; mesoscutum generally with silvery setae; fore coxa orange-brown to dark brown, mid and hind coxae dark brown; legs dark orange-brown to dark brown; fore wing ( Fig. 779) mostly infuscate with basal cell mostly hyaline, a small hyaline area at apex of venation this connected by a paler line to a larger hyaline area opposite, apex with a narrow subtriangular hyaline area; head ( Fig. 783) about 4.3-4.6X as wide as frontovertex, in facial view clearly longer than broad, subcircular, genae slightly curved and converging, hardly more curved inwards near mouth; frontovertex naked medially between anterior ocellus and scrobes; eye separated from scrobe by about diameter of anterior ocellus, area between eye and scrobe completely smooth and shiny; scrobes deep, sharply margined, carinate below eye; interantennal prominence with about 50 fairly conspicuous setae and dorsally broadly rounded without a median ridge; mandible with one acute tooth and a broad truncation; antenna ( Fig. 781) with scape about 3.2X as long as broad; F1-F4 longer than broad, F5-F6 transverse; linear sensilla on F3-F6; clava 3-segmented, slightly shorter than F4-F6 combined; sensory area enlarged, extending ventrally about 0.3X length of clava, apex obliquely truncate; head width about equal to flagellum length; mesoscutum ( Fig. 784) mostly with regular, polygonally reticulate sculpture, anterolateral areas with distinctly more longitudinally elongate sculpture; scutellum with a distinct, apical tuft of setae; wings fully developed, fore wing ( Fig. 779) about 2.8X as long as broad; parastigma slightly downcurved; costal cell dorsally with one or two apical setae, ventrally with a line of setae in proximal 0.8X, apex naked; area below proximal part of parastigma with a group of about 5-11 setae; apices of postmarginal and stigmal veins connected by a naked hyaline area that continues a little way into disc ( Fig. 778); apical bristle of postmarginal vein about 0.5X as long as marginal vein; mid tibial spur slightly longer than basitarsus; propodeum (Fig, 784) with about eight inconspicuous setae adjacent to spiracle, side naked; syntergum about 0.7X as long as mid tibia with apex broadly rounded, almost truncate; ovipositor ( Fig. 782) about 4.6X gonostylus or about as long as mid tibia; gonostylus about 0.6X as long mid tibial spur; ovipositor not exserted. Male: unknown.

Female (holotype): length, 1.65 ( CPD) .

Head mainly dark brown, virtually black; a very small area outside torulus, posterior part of gena and area above mandible pale orange; occipital margin faintly metallic blue, frontovertex generally with a dull dark green and purple sheen; area between eye and scrobe more strongly shining purple and green; temple with a relatively strong metallic green and blue-green sheen mixed with some purple, this continuing more weakly onto upper part of gena, area immediately below eye weakly shining coppery, violet and purple, lower part of gena dull with a weak blue-green and coppery sheen; scrobes very shiny, metallic; upper part of interantennal prominence with a purple sheen, below this green, a narrow coppery, purple, brassy and bright blue line more or less connects lower margins of toruli, below this metallic green with mouth margin mixed coppery and purple; frontovertex clothed with inconspicuous, pale brown setae, these continued as a line below eye; gena and interantennal prominence with relatively dense, scattered, short, translucent setae; antenna ( Fig. 781) with radicle mostly orange, apex dark brown; scape mostly white, ventral margin dark brown from base to about 0.75X along its length, dorsal margin and apex dark brown; pedicel and flagellum dark brown, almost black; maxillary palpus dark brown; thorax mostly dark brown; pronotum dark brown with sides mixed orange; propleuron orange-brown; prosternum brown; mesoscutum black generally with a weak brassy sheen and very weak blue, green, purple and coppery reflections, clothed in anterior one-quarter with brown setae, posterior three-quarters or so with paler, translucent, silvery setae; tegula dark brown with weak coppery and brassy reflections; axilla orange-brown, bordered dark brown, clothed with dark brown setae; scutellum matt black, anteriorly with golden brown setae, posterior setae and subapical tuft black; mesopleuron dark chestnut brown, anteriorly with a weak green, brassy, coppery and blue sheen, posteriorly with a coppery, purple and green sheen; fore coxa orange-brown; fore femur orange-brown bordered dark brown, tibia brown, tarsus brown; mid coxa dark brown; mid femur dark orange-brown, tibia orange with a subbasal white band, extreme base dark brown and a dark brown, external streak for most of its length, spur orange with apex dusky, tarsus orange; hind coxa dark brown, mixed orange-brown; hind femur dark brown with a small, subapical, orange-brown area, tibia dusky orange, bordered brown, tarsus brown; fore wing ( Fig. 779) mostly infuscate, largely hyaline towards base, venation brown; propodeum dark brown, medially with a metallic purple sheen, area around spiracle metallic dark blue and blue-green mixed with some purple, about 7 or 8 translucent, setae outside spiracle; gaster dark brown, mostly with a coppery-purple and brassy sheen, Gt3-Gt5 laterally with distinct coppery and green reflections; visible part of gonostylus very pale orange.

Head ( Fig. 783) in facial view about 4.4X as wide as frontovertex with gena rounded, in profile about 1.8X as high as deep, frontovertex slightly angled level with posterior ocelli, then weakly and evenly curved to top of scrobes, slightly angled towards mouth margin and virtually straight from top of scrobes to mouth margin, interantennal prominence slightly protuberant; occipital margin sharp, carinate; ocelli forming an angle of about 65°; frontovertex slightly shiny, with shallow, fairly regular, polygonally reticulate sculpture of mesh size smaller than diameter of eye facet, sculpture immediately above scrobes clearly coarser and transversely elongate, this area bordered laterally by a completely smooth area and broadly below by dorsal margin of scrobes; scrobes completely smooth; upper part of interantennal prominence narrowly smooth, but mostly with moderately slightly coarse, regular polygonally reticulate to imbricate-reticulate sculpture; temple with shallow, irregular, longitudinally elongate polygonally reticulate sculpture, posterior part of gena with similar sculpture, anterior part of gena with elongate, polygonally reticulate sculpture that is conspicuously deeper than that immediately below anterior ocellus; narrowest part between eye and scrobe hardly wider than diameter of anterior ocellus, completely smooth; scrobes deep, meeting dorsally, sharply margined, carinate below eye, very broadly ∩-shaped, interantennal prominence dorsally broadly rounded, without a median ridge; antenna as in Fig. 781; scape broadened and flattened, broadest above middle, about 3.2X as long as broad; F1- F4 longer than broad, F5-F6 transverse, segments wider and larger distally so that F6 is largest and widest; clava slightly broadened, slightly shorter than F4-F6 combined, sensory area slightly enlarged, extending about 0.3X along ventral surface, giving it an obliquely truncate appearance; eye not quite reaching occipital margin, separated by slightly more than diameter of facet, clothed with inconspicuous, very short setae that are much shorter than diameter of facet; inner eye margins subparallel, narrowest point of frontovertex about midway between anterior ocellus and top of scrobes; malar sulcus absent; clypeal margin medially very slightly convex; mandible with one acute tooth and a broad, slightly concave truncation; apical segment of maxillary palpus not enlarged, about as long as radicle. Relative measurements: HW 100, HH 108, FV 22.5, POL 14, OOL 0.5, OCL 12.5, AOL 13.5, EL 69, EW 50.5, MS 43, SL 43.5, SW 13.5.

Thorax ( Fig. 784) with pronotum hardly exposed behind head and about 0.6X as long as mesoscutum; pronotum slightly shiny with similar sculpture to that in ocellar area; mesoscutum mostly with regular, polygonally reticulate sculpture that is similar to that in ocellar area, anterolateral areas with finer, slightly narrower but more longitudinally elongate polygonal sculpture; axilla and scutellum with polygonally reticulate sculpture that is deeper than that on mesoscutum; visible part of mesoscutum about 2.1X as broad as long; scutellum about 1.2X as broad as long, with a distinct subapical tuft, setae mostly about 0.7X as long as scutellum; hind femur about 4.1X as long as broad; fore wing with venation and setation as in Figs 778, 779; costal cell with 2 or 3 setae dorsally at apex; apices of postmarginal and stigmal veins connected by a distinct, naked, hyaline streak ( Fig. 778); mid tibia without a distinct, external carina; propodeum ( Fig. 784) medially about 0.21X as long as scutellum and smooth. Relative measurements: FWL 96.5, FWW 35; HWL 85, HWW 22.

Gaster with hypopygium reaching about 0.4X to apex; syntergum about 0.7X as long as mid tibia, with apex broadly rounded, almost truncate; ovipositor hidden.

Paratype. Funicle with linear sensilla present only on F3-F6; gaster without “gland-like” structures on Gt1 or Gt5; hypopygium Fig. 780; ovipositor Fig. 782. Relative measurements: OL 43, GL 9.5 [MT 42].

Variation. Females vary in overall length from 1.42-1.76mm; the area below the torulus may be distinctly brassy and the head varies from 4.3-4.6X as wide as the frontovertex.

Male. Unknown.

DISTRIBUTION. Costa Rica.

HOSTS. Unknown.

MATERIAL EXAMINED.

Type material. Holotype E: COSTA RICA, Guanacaste, Santa Rosa NP, Hacienda 3-0, 26.x-16.xi.1985 (Janzen, Gauld). Paratypes: COSTA RICA, 1E, Guanacaste, Santa Rosa NP, H 10, 6-27.ix.1986 (D. Janzen, I.D. Gauld); 1E, Guanacaste, Santa Rosa NP, SE 6C, 25.iv.1987 (D. Janzen, I.D. Gauld); 1E, Guanacaste, Guanacaste NP, Est. Mengo Vn Cacao , v.1986 (Gauld, Janzen); 2E, Guanacaste, Est. Maritza ( ACG), LN 326900 373000, 600m, iii.1996 (M. Pereira); 2E, Guanacaste, PN Palo Verde, Sect. Palo Verde, LN 260952 385020, 50m, #55154, 7.ii-6.iii.2000 (I. Jiménez); 1E, Guanacaste, PN Palo Verde, Campo Aterrizaje, LN 259050 388400, 10m, 9.ii-12.iii.2001 (I. Jiménez); 1E, Guanacaste, PN Palo Verde, Campo Aterrizaje, LN 259050 386499, 10m, #59290, ix-x.2000 (I. Jiménez); 1E, Heredia, Santo Domingo, INBio Parque, LN 217300 526200, 1100m, #62082, i-iii.2001 (R. Zuñiga). Holotype in MZUCR, paratypes in NHMUK and MZUCR.

COMMENTS. Other than the characters given in the key, Cheiloneurus oshtan can be separated from other similar species ( seius , amadeus , medusa , grimus poeana ) by having a relatively broad scape that is about 3.2X as long as broad. Of the species listed, poeana has the broadest scape, about 3.5-3.7X as long as broad, but has the fore coxa white (see key).

Cheiloneurus nigrescens Howard (1897) , from Grenada (W.I.), is very close to oshtan and would run here in the above key to species (holotype examined, NHMUK). It differs in having the mesoscutum quite strongly metallic blue-green ( oshtan - weakly brassy with very weak blue, green, purple and coppery reflections); the head about as high as wide as broad ( oshtan – clearly higher than wide); the scape 5X as long as broad with the lower margin evenly curved and subparallel to upper margin ( oshtan – about 3.2X as long as broad with lower margin abruptly bulging in apical two-thirds) and the sculpture on FV above the scrobes deeper and forming more distinct cells than in oshtan .

Cheiloneurus loretanus De Santis , from Argentina, is also very close and could run here in the key (images of holotype examined, MLP). The two species are very close with a very similar pattern of paler and darker areas on the fore wing. Cheiloneurus loretanus has the fore wing about 2.6X as long as broad (more than 2.7X in oshtan ), the area below the proximal part of the parastigma with only two or three setae (11 in oshtan ); the parastigma more strongly curved downwards than in oshtan ; the dark setae on the proximal side of the linea calva less dense than in oshtan , the ventral margin of the scape more or less evenly curved (abruptly bulging in apical two-thirds in oshtan ), F5 and F6 almost quadrate (strongly transverse in oshtan ); the funicle segments gradually darkening towards the clava (unicolorous in oshtan );the face yellow (black with a metallic sheen in oshtan ) and the tegula, axilla and scutellum yellow (dark brown to black in oshtan ).

See also comments under herxius (p. 306) and poeana (p. 314).