Cheiloneurus extillus Noyes 2023, sp.nov.
Creators: name: Noyes, John Stuart
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Encyrtidae
Cheiloneurus
Cheiloneurus extillus

description: Cheiloneurus extillus sp.nov.   
(Figs 676-678)  
 DIAGNOSIS. Female (length about 2.7mm): body generally dark brown to black with a weak to moderate metallic sheen; antenna (Fig. 678) with scape pale orange, dark brown basally; pedicel mostly pale orange, dorsally dark brown proximally; funicle pale orange; clava dark brown; mesoscutum with silvery setae in posterior four-fifths; coxae white, mid coxa brown proximally; legs mostly pale orange, mid and hind tibiae each with a dark brown subbasal spot; fore wing (Fig. 677) hyaline, slightly yellowish below marginal vein; head about 4.7X as wide as frontovertex, in facial view about as broad as long, subcircular, genae converging, weakly and evenly curved; frontovertex naked medially below anterior ocellus; area between eye and scrobe nearly 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 short, sharp, upper tooth; scape about 5.0X as long as broad; funicle with F1-F4 longer than broad, F5 quadrate and F6 transverse; head width about equal to F2-F6 and clava combined; linear sensilla on F4-F6; clava 3-segmented, nearly as long as F2-F6 combined, sensory area large and forming an oblique truncation, extending slightly more than 0.5X along ventral margin; mesoscutum with polygonally reticulate sculpture; scutellum without a distinct, apical tuft of setae; wings fully developed; fore wing (Fig. 677) about 2.4X as long as broad; parastigma not curved downwards; costal cell dorsally with 4 or 5 setae at apex and ventrally with a single complete line of setae; area below proximal part of parastigma with a group of about 30 setae; apices of postmarginal and stigmal veins (Fig. 676) not connected by a naked hyaline area; apical bristle of postmarginal vein about 0.33X as long as marginal vein; mid tibial spur slightly longer than basitarsus; propodeum with about 40 setae around each spiracle, side naked; syntergum about 1.2X as long as mid tibia; ovipositor about 3.0X gonostylus or 1.8X mid tibia; gonostylus about 1.5X as long as mid tibial spur; exserted part of ovipositor about 0.4X length of mid tibial spur. Male: unknown.   
Female (holotype): length, including ovipositor, 2.66mm; excluding ovipositor, 2.53mm (CPD).  
Head black with a very weak blue and purple sheen on frontovertex, slightly coppery between posterior ocelli and occipital margin; occiput with a very slight blue and purple sheen; scrobal area largely purple mixed blue laterally and on lower part of interantennal prominence; mouth margin mixed coppery and purple; temple metallic blue and purple mixed brassy; area immediately below eye metallic coppery purple; frontovertex with inconspicuous dark brown setae; antenna (Fig. 678) with radicle dark brown; scape pale orange with a narrow, dark brown, basal ring; pedicel mostly pale orange, basal half or so dark brown dorsally; funicle pale orange; clava dark brown; thorax dark brown to black; pronotum mainly dull purple-brown with a slight brassy sheen; mesoscutum with a slight purple sheen, bluish in some lights, posterior margin weakly coppery purple, setae pale brown in anterior one-fifth, posterior four-fifths with uniform, translucent, silvery setae; tegula dark brown; axilla duller than mesoscutum, with a slight purple and brassy sheen; scutellum virtually black, but with a very weak metallic green sheen with some purple reflections, clothed in dark brown setae, extreme apex and sides with a metallic green and brassy sheen; metanotum with a slight purple sheen; mesopleuron in posterior half with a purple and brassy sheen, medially blue and anteriorly mixed green, brassy and purple; fore coxa white; fore femur white, pale orange distally, fore tibia pale orange; mid coxa white, brown basally; mid femur white to very pale yellow, distally pale orange, tibia pale orange with an elongate, dark brown spot externally in proximal two-fifths; hind coxa white; hind femur very pale yellow, pale orange in distal half, tibia mostly pale orange with an elongate dark brown, subbasal spot externally; tarsi pale orange, hind tarsus palest, pretarsi slightly dusky; fore wing (Fig. 677) virtually hyaline, slightly yellowish below marginal vein; venation pale brown; propodeum dark purple-brown; sides metallic green with conspicuous silvery setae in spiracular area; gaster dark purple-brown, Gt1 mostly metallic blue-green, 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 orange-brown.  
Head about 4.7X as wide as frontovertex, anteriorly almost evenly rounded in profile, sublenticular; occipital margin acute, occiput with an incomplete median groove above foramen, not reaching occipital margin; ocelli forming an angle of about 60°; 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; gena and temple with more elongate sculpture of larger mesh; scrobes shallow, meeting dorsally, dorsal and lateral margins weakly rounded; antenna as in Fig. 678; scape hardly broadened and flattened, about 5X as long as broad; F1 clearly longer than broad, F2-F4 slightly longer than broad, F5 quadrate, F6 transverse, segments broadest distad; linear sensilla present only on F4-F6; clava slightly broadened, about as long as F2-F6 combined, both sutures clearly oblique, sensory area enlarged, extending about 0.6X along clava ventrally, giving it a distinct, obliquely truncate appearance; eye reaching occipital margin, clothed with fairly conspicuous setae, each very slightly longer than diameter of facet; inner eye margins slightly converging anteriorly; malar sulcus absent; mandible with 2, relatively long, acute, lower teeth, and a short, upper tooth. Relative measurements: HW 99, HH 100, FV 21, OD 6.5, POL 14, OOL 0.5, OCL 6.5, AOL 16.5, EL 65, EW 51, MS 40, SL 58, SW 11.  
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, much more elongate on sides; extreme apex and sides completely smooth and shiny; visible part of mesoscutum about 1.7X as broad as long; scutellum about as long as broad, without a distinct subapical tuft, setae about one-third as long as scutellum; hind femur about 4.5X as long as broad; fore wing with venation and setation as in Figs 676, 677; costal cell with 5 setae dorsally at apex; no naked streak present between apices of postmarginal and stigmal veins (Figs 676); propodeum with moderately dense setae in spiracular area, side naked, medially about 0.1X as long as scutellum and with some shallow, irregular polygonally reticulate sculpture. Relative measurements: FWL 121, FWW 51; HWL 92, HWW 27.  
Gaster without “gland-like” structures on Gt1 or Gt5; hypopygium reaching about one-third towards apex; syntergum about 1.2X as long as tibia, with apex produced and very acute; ovipositor exserted, the exserted part very slightly more than one-third length of mid tibial spur. Relative measurements: OL 115, GL 38.5 [MT 64].  
Variation. Known only from holotype.  
Male. Unknown.  
DISTRIBUTION. Costa Rica.  
HOSTS. Unknown.  
MATERIAL EXAMINED.  
 Type material. Holotype E: COSTA RICA, Heredia, 6km ENE Vara Blanca, 10°11’N 84°07’W, 2000m, 20/M/TN, iv.2002 (INBio-OET-ALAS). Holotype in NHMUK.   
 COMMENTS. Cheiloneurus extillus is similar to onestas and hamadryas, all three species having relatively short funicle segments, an obliquely truncate clava, hyaline fore wing and often no distinct subapical tuft of setae on the scutellum. It can be separated from both other species by having the hind femur entirely yellow to pale orange, the ovipositor about 3X as long as a gonostylus whereas in the other species the hind femur is dark brown in its apical half, the ovipositor is at least about 4X as long as a gonostylus. It can also be separated from onestas in the scape being about 5X as long as broad and having about 35-40 setae on the side of the propodeum near the spiracle, whilst in onestas the scape is about 4X as long as broad and there are only about 10 setae on the side of the propodeum.
description: Published as part of 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), pp. 1-921 in Taxonomic Monographs on Neotropical Hymenoptera (Oxford, England) (Oxford, England) 2 (11) on pages 270-271, DOI: 10.5281/zenodo.8074943