Palpostilpnus singaporensis, Reshchikov & Santos & Liu & Barthélémy, 2019

Reshchikov, Alexey, Santos, Bernardo F., Liu, Jing-Xian & Barthélémy, Christophe, 2019, Review of Palpostilpnus Aubert (Hymenoptera, Ichneumonidae, Phygadeuontinae), with the description of ten new species, European Journal of Taxonomy 582, pp. 1-63 : 52-55

Palpostilpnus singaporensis sp. nov.

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Figs 26–27

Diagnosis

Body short and stout ( Fig. 26A ). Postero-ocellar distance 3.6 times ocular-ocellar distance ( Fig. 27E ). Epomia indistinct. Epicnemial carina long and curved in middle of mesopleuron ( Fig. 26C ). Propodeal carinae absent except for vestiges of posterior transverse carina and apical portion of dorsal longitudinal carina ( Fig. 27B ). Ovipositor 0.3 times as long as hind basitarsus ( Fig. 27C ). Body mostly yellow, with head, most of antenna, apical part of hind tibia and hind margin of T1–T4 black, scape and palpus white ( Fig. 26A ). Wings hyaline ( Fig. 27F ).

Etymology

The specific name is derived from the name of the type locality, Singapore.

Material examined

Holotype

SINGAPORE • ♀; Nee Soon Swamp Forest ; 1°23′00.3″ N, 103°48′46.5″ E; Malaise trap (NS1); 13–20 Mar. 2013; NUS leg.; barcode: ZRC_39348; LKCNHM.

Paratypes

BRUNEI • 1 ♀; Belait District, Labi (mukim); 200 m a.s.l.; mixed dipterocarp forest; Aug.–Sep. 1979; I. Gauld leg.; NHMUK .

MALAYSIA • 1 ♀; Sarawak, 4 th Division, Gunung Mulu National Park ; May–Jun. 1978; N.M. Collins, RGS Expedition leg.; NHMUK .

SINGAPORE • 1♀; same collection data as for holotype; 3–10 Jul. 2013; barcode: ZRC_BDP0039318; NHRS PT-HEVA000010862 • 1 ♀; Nee Soon Swamp Forest ; 1°23′04.2″ N, 103°48′40.7″ E; Malaise trap (NS2); 5–12 Mar. 2014; NUS leg.; barcode: ZRC_39559; LKCNHM .

Description

Female (holotype)

SIZE. Fore wing length 3.3 mm. Body short and stout, 1.28 times as long as high ( Fig. 26A ).

HEAD. Face 2.0 times as broad as high, centrally slightly convex; finely granulose ( Fig. 26B ). Clypeal suture very weak. Clypeus slightly convex, matte, slightly striate apically, evenly convex downwards, with sharp apical margin. Mandible basally smooth; teeth sharp, of subequal length. Malar space granulated, 0.8 times as long as basal mandible width. Gena glossy, smooth and shiny, with weak transverse carina dorsally between vertex and eye. Vertex ( Fig. 27E ) finely punctate, distance between punctures approximately 1–1.2 times diameter of punctures, posterior portion from behind ocelli to occipital carina slanted almost vertically, slightly concave. Postero-ocellar distance 3.6 times ocularocellar distance ( Fig. 27E ). Frons finely coriarious, lower portion slightly concave. Antenna slightly shorter than body, with 27 flagellomeres, median portion moderately thickened. Occipital carina complete.

MESOSOMA. Pronotum coarsely punctate. Epomia indistinct. Mesoscutum ( Fig. 26E ) wide and short, convex, with coarse, dense punctures. Notaulus indistinct. Scutellum slightly convex, with coarse dense punctures. Postscutellum transverse, smooth. Centre of mesopleuron smooth, but outer areas (near epicnemial carina, speculum and sternaulus) densely punctate (as pronotum and mesoscutum), pubescent with yellowish setae. Epicnemial carina long and curved in middle of mesopleuron ( Fig. 26C ). Sternaulus distinct, extending over entire mesopleuron. Metapleuron with distinct shallow punctures, distance between punctures 0.2 times diameter of puncture. Juxtacoxal carina distinct, but short. Submetapleural carina complete. Fore wing with 1cu-a distinctly distad of M becoming Rs, 3rs-m absent, distal abscissa of vein M spectral; ramulus absent; length of vein Cu slightly longer than 2cu-a ( Fig. 27F ). Hind wing with cu-a strongly inclivous and interrupted at lower 0.2. Distal abscissa of Cu spectral. Distal abscissa of M spectral. Inner profile of fore basitarsus with basal half slightly bent. Hind coxa anteriorly punctate, posteriorly smooth. Hind femur stout, length 4.2 times its maximum width. Basal portion of hind tibia slender, gradually thick toward apex. Longer spur of hind tibia 0.56 times as long as length of hind basitarsus. Propodeum steeply sloping in lateral view, with sparse coarse punctures, posterocentrally smoother ( Figs 26 B–C). Propodeal carinae absent except for vestiges of posterior transverse carina and apical portion of lateromedian longitudinal carina ( Fig. 27B ).

METASOMA ( Fig. 27A ). T1 2.0 times as long as apically broad, smooth, petiole flat, concave; postpetiole wide, without median dorsal carina; dorsolateral and ventrolateral carinae distinct; spiracle small, round, slightly prominent. T2–T6 coarsely and sparsely punctate. T2 widened posteriorly, 0.5 times as long as apically broad, with distinct gastrocoelus. T3 0.6 times as long as apically broad, parallel-sided. Ovipositor 0.3 times as long as hind basitarsus ( Fig. 27C ).

COLOUR. Body mostly yellow. Antenna dorsally, head, posterior stripe on T1–T4 and apical part of hind tibia black. Apex of mandible reddish. Antenna ventrally brownish. Scape ventrally, palpi, fore and middle trochanters, fore femur, apical part of metasoma and hind tarsus pale yellow.

Male

Unknown.

Variation

Fore wing 3.3–3.5 mm long. Antenna with 26–27 flagellomeres. Specimen from Brunei with black transverse stripe on apex of mesoscutum; black spots on hind tibia smaller; metasoma without distinct black stripes, but slightly darkened on posterior portion; ovipositor 0.4 times as long as hind basitarsus.

Remarks

This species is similar to P. hainanensis sp. nov., but it can be distinguished from the latter by having a distinctly stouter body (1.28 times vs 1.60 times as long as high in P. hainanensis sp. nov.) and the following combination of characters: T1 2.0 times as long as apically broad (1.8 times in P. hainanensis sp. nov.), ovipositor 0.3 times as long as hind basitarsus (1.3 times in P.hainanensis sp. nov.), mesopleuron entirely yellow and hind margin of T1–T4 black or at least distinctly darkened.

Figures

Fig. 26. Palpostilpnus singaporensis sp. nov., holotype, ♀ (LKCNHM). A. Lateral habitus. B. Head, anterior view. C. Mesopleuron. D. T1, dorsal view. E. Scutum.

Fig. 27. Palpostilpnus singaporensis sp. nov., holotype, ♀ (LKCNHM). A. Metasoma, dorsal view. B. Propodeum, dorsal view. C. Ovipositor. D. Antennae. E. Vertex. F. Wings.