Eopelma gibsoni, Fusu, Lucian & Polaszek, Andrew, 2017

Fusu, Lucian & Polaszek, Andrew, 2017, Description, DNA barcoding and phylogenetic placement of a remarkable new species of Eopelma (Hymenoptera: Eupelmidae) from Borneo, Zootaxa 4263 (3), pp. 557-566 : 559-561

Eopelma gibsoni sp. nov.

Figs 1–9 (♂).

Type material. Holotype ♂: MALAYSIA , Sarawak: Borneo, Gunung Mulu National Park, Long Lansat, along stream, 55m. 17 Aug 2011, ROM _ OSU 308535, 04 °00'03.5"N, 114°48'49.8"E, Sweeping, A Polaszek, DC Darling, E Talamas, NF Johnson. Deposited at the Forest Research Centre of the Sarawak Forestry Department , Malaysia.

Condition of the holotype: empty exoskeleton resulting from whole body DNA extraction, glued with the right ventral part to a rectangular card. Entire.

Etymology. Named in honour of the Canadian chalcid worker and Eupelmidae specialist, Gary A. P. Gibson.

Description. Holotype ♂: length = 2.15 mm ( Fig. 1 ).

Colour and setation. Head ( Figs 2, 5 ) yellow to brown-yellow except irregularly and asymmetrically darker brown between the inner orbits from the posterior margin of the head to the posterior ocelli ( Fig. 2 ); lower face and gena with transverse brown stripe below lower eye orbit at about dorsal edge of clypeus and with conspicuous band of white, reflective, lanceolate, decumbent setae between lower eye orbits along dorsal edge of brown stripe; parascrobal and scrobal areas with two similar bands of setae interrupted by the scrobal channels, one at level of dorsal half of torulus and the other above it, with three transverse brown stripes: dorsal to, ventral to, and in between the two setal bands ( Fig. 5 ). [When the specimen was freshly collected the three brown stripes on the upper face continued across the compound eyes ( Fig. 6 , arrows) and were very conspicuous (observation by A. Polaszek). They faded during one and a half years storage in 95% ethanol at low temperature, and disappeared altogether upon proteinase K digestion ( Fig. 6 was taken in alcohol before processing for DNA extraction).] Upper parascrobal region with a couple of slightly lanceolate white setae along each orbit and above upper brown stripe, but otherwise head inconspicuously setose except for described setal bands and relatively long hair-like setae on lower face ventral to lower brown stripe. Maxillary and labial palpi yellow, mandible with apical half brown.

Scape longitudinally patterned, bicolored: with off-white dorsoapical spot and a brown, subapical, strongly oblique ring below it; narrowly white basally followed by a brown half-ring lacking from the inner and dorsal surfaces so that the inner surface of the scape is white between the apex of the radicle and the subapical brown ring and outer surface with an oblique white band between the two brown areas ( Fig. 3 ); radicle brown basally, darker brown apically, the darker areas separated by a white ring; pedicel with about basal one-third yellow-white and apical two-thirds brown; fl1 pale yellow-white, fl2 brown except apex white, fl3 white except base brown, fl4 and fl5 dark brown, fl6 white, fl7 dark brown; clava brown except white apically ( Fig. 3 ).

Mesosoma brown-yellow except posterolateral margin of pronotum anterior to spiracle, propleuron apically adjacent to fore coxa, prepectus ventrally, acropleuron, posterior half of prosternum and mesopectus brown; bare except pronotum sparsely inconspicuously setose laterally and with four longer suberect admarginal setae posteriorly, mesoscutellum at about mid-length with one small erect seta laterally and a comparatively stronger seta posterolaterally on either side (there is an additional small pore on each side at about two-thirds mesoscutellum length that might represent the remains of an additional pair of setae that were abraded); mesoscutum laterally, axillula, propodeum lateral to spiracle, and mesepisternum sparsely setose. Legs mostly pale yellow except apical tarsomeres of fore and hind tarsi dark brown and mesotarsal pegs and setae on distal tarsomeres variably dark brown, procoxa mostly and metacoxa partly brown, and meso- and metafemur brown basally; mid tibia with long, erect, brown setae over dorsal and anterior surfaces.

Fore wing venation with alternating brown and pale areas, with stout black setae and tuft of spine-like setae on parastigma, medially on marginal vein, and at juncture of marginal, postmarginal and stigmal veins; costal cell vaguely infuscate except more brown distally, dorsally with numerous dark setae in front of parastigma, but otherwise bare and ventrally similarly setose distally and mostly with a single row of comparatively inconspicuous white setae along length; wing base hyaline to vaguely infuscate except mediocubital fold brown; basal cell entirely setose, with dark setae except for circular region with white setae distally; cubital and vanal areas similarly setose, but with a large semicircular bare area at wing margin behind mediocubital notch; mediocubital notch with a small, dark-brown, sclerified area; disk conspicuously and extensively infuscate beyond basal fold, without linea calva, uniformly setose with dark setae except for small hyaline area with white setae behind pale base of marginal vein, a much smaller, transverse area behind apical pale region of marginal vein, and two circular hyaline spots with white setae beyond stigmal vein, one at leading margin and second at the hind margin, and somewhat paler apically with some pale setae ( Figs 4, 9 ). Hind wing venation brownish except parastigma dark-brown posteriorly, hyaline except slightly infuscate below parastigma along basal fold.

Metasoma sparsely setose, with longer brown setae laterally, brown with multicoloured metallic luster under some angles of light and yellow paramedial areas on Mt2–Mt6.

Structure and sculpture. Head in dorsal view ( Fig. 2 ) with a slight indication of a transverse vertexal carina, with interocular distance about 0.45× head width and about 1.7× eye width; in lateral view ovoid and about 1.18× as high as long; reticulate with isodiametric cells (sculpture on frontovertex with mesh from slightly smaller to slightly larger than eye facet) except occiput, gena, and lower face coriaceous to alutaceous. Eye large, 1.2× as long as wide and length 2.3× malar space. OOL: POL: LOL: MPOD = 1.44: 1.55: 1.1: 1.0. Antenna with combined length of pedicel + flagellum about 2.1× head width; scape about 4.5× as long as maximum width, in outer view with subparallel edges and ventral and dorsal margins evenly curved; pedicel in lateral view about 2.7× as long as wide; fl1 2.8× as long as wide and 1.2× as long as fl2; fl2 about 2.3× as long as wide; fl3 subconical, basally about as wide as fl2 and gradually wider apically, 4× as long as wide apically; fl4 cylindrical and 0.74× as long as fl3; fl5 to fl7 subequal to or slightly longer than fl4, slightly compressed and in lateral view wider than preceding flagellomeres; clava as wide as fl7 and about 4× as long as wide, slightly shorter than combined length of apical two funiculars.

Pronotum subtriangular with posterior edge broadly incurved, about 0.7× as long as mesoscutum, reticulate with mesh size larger than on vertex; prepectus meshlike coriaceous to reticulate to coriaceous-imbricate; mesoscutum 0.56× as long as wide, reticulate with cells conspicuously larger and more isodiametric compared to pronotum; scutellar-axillar complex nearly flat except for laterally declined axillula and mesoscutellum and axilla barely convex, reticulate with cells similar to those on metanotum and propodeum medially; mesoscutellum 1.7× as long as wide, trapezoidal, and axilla plus axillula 1.3× as long as wide; metanotum transverse-rectangular, medially only slightly shorter than propodeum, almost flat except metascutellum slightly convex and differentiated by reticulate sculpture; propodeum with a thin flange over base of petiole, evenly convex, plical region mesal to each propodeal spiracle with a longitudinal non-impressed dark line corresponding to an internal carina and with a triangular reticulated area medially; acropleuron more or less isodiametric meshlike reticulate anteriorly, with cells defined by at most very slightly raised ridges. Mesotibial apical spur 0.8× as long as mesobasitarsus; mesobasitarsus about 3× as long as wide, second to fourth tarsomeres compressed and higher than long, and last tarsomere enlarged ( Fig. 7 ). Mesotarsus ventrally with pegs along anterior margin and spine-like setae along posterior margin, with apical seta of the four basal mesotarsal segments stronger and darker ( Fig. 8 ); dorsally with a conspicuous, black, compressed, feather-like seta on the fourth tarsomere and two similar but gradually smaller setae on the last tarsomere, the three basal tarsomeres dorsally only with spine-like setae ( Fig. 7 ). Fore wing 2.8× as long as wide, cc: mv: pmv: stv = 7.6: 4: 2.4: 1.0.

Metasoma flattened, about 2× as long as wide and about 1.4× as long as mesosoma, with petiole large and smooth and terga shallowly mesh-like reticulate except Mt2 smooth and shiny; syntergum smooth, short-triangular and evenly convex.

Figures

FIGURES 1 – 9. Habitus and details of the unique male holotype of Eopelma gibsoni: 1, lateral habitus; 2, head and mesosoma, dorsal; 3, antenna; 4, left fore wing; 5, head, frontolateral; 6, head, frontoventral, in ethanol before DNA extraction; 7, mesotarsus, lateral; 8, mesotarsus, ventral; 9, right fore wing, detail. Arrows in 6 point to the remnants of the dark stripes on the eye. The dark region on the eye in 1 and 5 are not bands of pigment but an artefact of seeing internal head structures through the lenses of the eye, rendered transparent after the proteinase K treatment.