Cheiloneurus paean, 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 : 349-351

Cheiloneurus paean sp.nov.

( Figs 871-877)

DIAGNOSIS. Female (length about 1.6mm): body almost completely dark brown with a weak to moderate metallic sheen; antenna ( Fig. 871) with scape mostly white with dorsal and ventral margins largely brown; pedicel and flagellum dark brown; mesoscutum with silvery setae in posterior half; fore and hind coxae white, mid coxa dark brown; legs dark orange-brown to dark brown, fore and mid legs slightly paler; fore wing ( Fig. 875) mostly infuscate with basal cell mostly hyaline, a small hyaline area at apex of venation, apex with a small, slightly paler area; head ( Fig. 877) about 5.3X as wide as frontovertex, in facial view clearly longer than broad, subrectangular, genae slightly curved but hardly converging, more strongly 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; scrobes deep, sharply margined, carinate below eye; interantennal prominence with about 30 inconspicuous setae and dorsally broadly rounded without a median ridge; mandible with three short teeth; antenna ( Fig. 871) with scape about 4.0X as long as broad; F1-F4 longer than broad, F5-F6 quadrate or transverse; linear sensilla on F3-F6 or F4-F6; clava 3-segmented, nearly as long as F3-F6 combined; sensory area enlarged, extending ventrally about 0.5X length of clava, apex obliquely truncate; head width slightly less than flagellum length; mesoscutum ( Fig. 873) in anterior two-thirds with longitudinally elongate striate to striate-reticulate sculpture, posterior one-third with regular, polygonally reticulate sculpture; scutellum with a distinct, apical tuft of setae; wings fully developed, fore wing ( Fig. 875) about 2.6X as long as broad; parastigma slightly downcurved; costal cell dorsally with two or three apical setae, ventrally with a line of setae in proximal 0.6X; area below proximal part of parastigma with a group of about 20 setae; apices of postmarginal and stigmal veins connected by a naked hyaline area that continues a little way into disc ( Fig. 876); apical bristle of postmarginal vein about 0.8X as long as marginal vein; mid tibial spur slightly longer than basitarsus; propodeum with about three inconspicuous setae adjacent to spiracle, side naked; syntergum about 0.9X as long as mid tibia with apex broadly angular; ovipositor ( Fig. 874) about 3.6X gonostylus or about 1.3X as long as mid tibia; gonostylus about as long mid tibial spur; exserted part of ovipositor about 0.5X as long as mid tibial spur. Male: unknown.

Female (holotype): length, including ovipositor, 1.61mm; excluding ovipositor, 1.52mm ( CPD) .

Head mainly dark brown, virtually black; a very small area outside torulus, scrobes partially and lower part of interantennal prominence orange; occipital margin faintly metallic dark blue, vertex between posterior ocelli and occipital margin shining purple, a little metallic green between posterior ocelli, blue and purple between ocelli, relatively dull purple and green from ocelli to top of scrobes; area between eye and scrobe more strongly shining purple; temple with a relatively strong metallic green and blue-green sheen mixed with some purple, this continuing more weakly to upper part of gena, area immediately below eye weakly shining purple and green, lower part of gena dull with a weak purple and green sheen; scrobes smooth, but with only a weak sheen; upper part of interantennal prominence with a purple sheen, below this with weak green reflections, below this mixed coppery and purple to mouth margin; 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. 871) with radicle mostly orange, sides 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, proximal segments mixed pale brown; thorax mostly dark brown; pronotum dark brown, side weakly mixed orange; propleuron and prosternum brown; mesoscutum black, anterior half completely matt with dark brown setae, posterior half with distinct blue-green and purple reflections and with silvery setae, these slightly more dense laterally, posterior margin purple-brown with a slight brassy sheen; tegula dark brown with weak coppery and brassy reflections; axilla orange-brown with weak green reflections, bordered dark brown, clothed with dark brown setae; scutellum orange-brown in anterior half, with golden brown setae and some very weak green reflections, posterior half dark orange-brown with dark brown setae, 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 white; 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 dark brown, tarsus white, apical tarsomere dark brown; hind coxa white, ventrally brown at base; hind femur dark brown with a small, subapical, orange-brown area, tibia dark brown, tarsus white, two apical tarsomeres dark brown; fore wing ( Fig. 875) mostly infuscate, largely hyaline towards base, venation brown; propodeum dark brown, medially with a metallic purple sheen, area around spiracle metallic green mixed with purple and some coppery, about 5 or 6 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 dark brown with apex pale orange.

Head ( Fig. 877) in facial view about 5.3X as wide as frontovertex with gena rounded, in profile about 1.7X 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 50° frontovertex virtually smooth and quite shiny behind posterior ocelli, moderately shiny in ocellar area, but more anterior parts less shiny, frontovertex in front of posterior ocelli with distinct polygonally reticulate sculpture of mesh size subequal to eye facet, sculpture immediately above scrobes clearly much 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 moderate, 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 coarse, polygonally reticulate sculpture similar to that immediately above scrobes; 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. 871; scape broadened and flattened, broadest above middle, about 4X as long as broad; F1-F4 longer than broad, F5 quadrate, F6 transverse, segments wider and larger distally so that F6 is largest and widest, linear sensilla present only on F3-F6 or F4-F6; clava slightly broadened, nearly as long as F3-F6 combined, sensory area slightly enlarged, extending about 0.45X along ventral surface, giving it an obliquely truncate appearance; eye not quite reaching occipital margin, separated by about 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 slightly in front of anterior ocellus; malar sulcus absent; clypeal margin medially straight; mandible with three teeth, upper tooth slightly rounded; apical segment of maxillary palpus not enlarged, about as long as radicle. Relative measurements: HW 89.5, HH 96, FV 17, POL 8, OOL 0, OCL 14, AOL 11.5, EL 65, EW 46, MS 46, SL 42, SW 10.5.

Thorax ( Fig. 873) with pronotum hardly exposed behind head and about 0.6X as long as mesoscutum; pronotum slightly shiny with similar sculpture to area in front of anterior ocellus; anterior two-thirds of mesoscutum with fairly regular, fine, longitudinally elongate, striate to striate-reticulate sculpture, more extensive laterally, of similar depth to that on pronotum, posterior half with slightly more rounded, polygonally reticulate sculpture that is perhaps a little shallower than that on anterior part; axilla and scutellum with coarser, polygonally reticulate sculpture that is deeper than that on mesoscutum, sculpture on side of scutellum more longitudinally elongate; visible part of mesoscutum about 2X as broad as long; scutellum about 1.1X as broad as long, with a distinct subapical tuft, setae mostly about 0.6X as long as scutellum; hind femur about 4.3X as long as broad; fore wing with venation and setation as in Figs 875, 876; costal cell with 1 seta dorsally at apex; apices of postmarginal and stigmal veins connected by a distinct, naked, hyaline streak ( Fig. 876); mid tibia with an indistinct, external carina in proximal half; propodeum ( Fig. 873) medially about 0.26X as long as scutellum and smooth. Relative measurements: FWL 116, FWW 44; HWL 99, HWW 24.5.

Gaster without “gland-like” structures on Gt1 or Gt5; hypopygium ( Fig. 872) reaching about 0.4X to apex; syntergum about 0.9X as long as mid tibia, with apex broadly angular; ovipositor ( Fig. 874) slightly exserted, the exserted part about half as long as mid tibial spur or about 0.2X mid tibia. Relative measurements: OL 54, GL 15 [MT 42].

Variation. Only holotype examined.

Male. Unknown.

DISTRIBUTION. Costa Rica.

HOSTS. Unknown.

MATERIAL EXAMINED.

Type material. Holotype E: COSTA RICA, Puntarenas, Pen Osa , 5km NW Puerto Jimenez, 8°33’N 83°21’W, 10m, xi-xii.1992 (P. Hanson) . Holotype in NHMUK .

COMMENTS. Cheiloneurus paean belongs to a group of species that are very similar in general habitus and colouration to nigrescens . It can be separated reliably from these species using the characters provided in the key. In addition, it can be distinguished from many of these ( amadeus , medusa , seius , grimus , oshtan , etc.) by having both the fore coxa and hind coxa white and relatively longer gonostyli. In paean the gonostyli are more than one-quarter as long as the ovipositor whereas in many other similar species both the fore and hind coxae are brown and the gonostyli are less than one-quarter as long as the ovipositor.