Alexeter melanicus, Li & Sun, 2022

T., Li & S. P., Sun, 2022, The genus Alexeter Förster (Hymenoptera, Ichneumonidae) in China, with descriptions of three new species, European Journal of Taxonomy 789 (81), pp. 81-103 : 92-95

Alexeter melanicus sp. nov.

urn:lsid:zoobank.org:act:5CAC94F3-CD1B-4D39-8233-2A044AA3F29A

Figs 24–34

Diagnosis

Face ( Fig. 25 ) approximately 1.5× as wide as long, with dense indistinct punctulate-reticulate sculpture. Malar space about 0.3 × as long as basal width of mandible. Areolet ( Fig. 30 ) absent; distance between 2rs-m and 2m-cu 1.1× as long as 2rs-m. Lateromedian longitudinal carinae of propodeum ( Fig. 31 ) strong, distinctly narrowed medially; area between lateromedian longitudinal carinae shiny, with indistinct irregular wrinkles. First metasomal tergite ( Fig. 32 ) approximately 2.0× as long as posterior width.

Differential diagnosis

The new species is similar to A. angularis ( Uchida, 1952) , but can be distinguished from the latter by the following combination of characters: clypeus shiny, with relatively dense, distinct punctures; areolet absent; ventral profile of mid tarsomeres yellowish white, dorsal profiles brown; hind tarsomeres 1–4 yellowish white. Alexeter angularis : clypeus shagreened, with very sparse fine punctures; areolet present; mid and hind tarsi entirely black.

Etymology

The specific name is derived from the almost entirely black body.

Material examined

Holotype CHINA • ♀; Guizhou Province, Jiangkou, Fanjingshan National Nature Reserve, Lengjiaba ; 840 m a.s.l.; 15 June 2019; interception trap; GSFGPM.

Paratypes CHINA • 2 ♀♀, 11 ♂♂; same data as for holotype; 18 May to 8 Jun. 2019; interception trap; GSFGPM • 1 ♀; same data as for holotype; 1250 m a.s.l.; 15 may 2019; interception trap; GSFGPM .

Description

Female

MEASUREMENTS. Body ( Fig. 24 ) length 12.4–14.1 mm. Fore wing length 9.9–11.3 mm. Ovipositor sheath length 0.5–0.6 mm.

HEAD. Inner orbits almost parallel, slightly concave near antennal sockets. Face ( Fig. 25 ) approximately 1.5 × as wide as long, with dense indistinct punctulate-reticulate sculpture; sides and median portion slightly evenly convex; upper margin indistinct, with median small tubercle.Clypeus shiny, approximately 2.9 × as wide as long, with relatively large punctures ( Fig. 25 ); apical margin almost truncate. Mandible shagreened, with brownish yellow setae; teeth smooth, upper tooth distinctly shorter than lower tooth. Malar space shagreened, about 0.3× as long as basal width of mandible, with brownish yellow setae. Gena finely shagreened, evenly convergent posteriorly, with fine indistinct punctures. Vertex ( Fig. 26 ) with sculpture as gena; postocellar line approximately 0.7 × as long as ocular-ocellar line. Frons slightly evenly concave, finely shagreened. Antenna with 44–49 flagellomeres; ratio of length from first to fifth flagellomeres approximately: 2.4:1.1:1.1:1.0:1.0. Occipital carina complete, lower end joining hypostomal carina above base of mandible.

MESOSOMA. Anterior and upper-posterior portions of pronotum ( Fig. 27 ) shagreened, with fine punctures; upper portion of lateral concavity with distinct transverse wrinkles.Mesoscutum ( Fig. 28 ) finely shagreened. Notauli weak. Scutoscutellar groove almost shiny. Scutellum distinctly convex, with fine indistinct punctures. Postscutellum shagreened, anterior margin transversely deeply concave. Mesopleuron ( Fig. 27 ) almost flat, shagreened; anterior portion and along upper margin with fine punctures; speculum smooth, upper portion with sparse indistinct punctures. Upper end of epicnemial carina approximately reaching 0.4 distance to subtegular ridge. Metapleuron slightly convex, with sculpture mainly as mesopleuron; lower posterior portion with short indistinct wrinkles; submetapleural carina complete, anterior portion strongly convex. Ratio of length of hind tarsomeres ( Fig. 29 ) from first to fifth approximately: 4.7:2.3:1.7:1.0:1.2. Wings ( Fig. 30 ) slightly brownish, hyaline. Fore wing with vein 1cu-a distal to M&RS by approximately 0.3× length of 1cu-a.Areolet absent. Distance between 2rs-m and 2m-cu 1.1 ×as long as 2rs-m.Postnervulus intercepted at middle. Hind wing vein 1-cu 2.3 × as long as cu-a. Propodeum ( Fig. 31 ) evenly convex, finely shagreened, with dense brownish white setae; lateromedian longitudinal carinae strong, distinctly narrowed medially, area between lateromedian longitudinal carinae shiny, with indistinct irregular wrinkles; area petiolaris shiny, with indistinct longitudinal wrinkles. Propodeal spiracle oblique elliptical.

METASOMA. First metasomal tergite ( Figs 32–33 ) approximately 2.0× as long as posterior width, strongly and evenly narrowed to base; almost shiny; base deeply concave medially; with irregular fine punctures; anterior portion of latero-median carina along median concavity present; dorso-lateral carinae almost complete; spiracle circular, small, located approximately at middle of first metasomal tergite. Second metasomal tergite ( Fig. 32 ) approximately 0.8× as long as apical width; anterior portion slightly rough, finely indistinctly punctate; posterior portion with fine distinct punctures. Third and subsequent tergites almost shiny. Third and fourth tergites with fine distinct punctures. Ovipositor sheath ( Fig. 34 ) approximately 3.1× as long as its width, slightly widened medially. Ovipositor ( Fig. 34 ) compressed, with subapical dorsal notch.

COLORATION ( Fig. 24 ). Black, except for following: lateral portion of clypeus, upper and lower median portions of mandible yellowish brown. Maxillary and labial palpi darkish brown. Dorsal profile and apex of fore femur red brown. Ventral profiles of fore tibia and tarsomeres yellowish brown. Dorsal profiles of fore tibia and tarsomeres dark brown. Ventral profile of mid tibia dark brown; Ventral profile of mid tarsomeres yellowish white, dorsal profiles brown. Hind tarsomeres 1–4 yellowish white, tarsomere 5 mainly dark brown. Pterostigma yellowish brown. Veins brownish black.

Male

MEASUREMENTS. Body length 11.6–13.2 mm. Fore wing length 8.6–9.7 mm.

BODY.Antenna with42–45flagellomeres.Black, except for following:face except upper median longitudinal spot, clypeus, mandible except tooth, maxillary and labial palpi, ventral profile of scape, upper-posterior corner of pronotum, anterolateral margin of mesoscutum, tegula, subtegular ridge, posterior margin of tergite 2, median irregular spot of tergite 3, anterior median triangular spot of tergite 4 yellow to yellowish white. Pterostigma and veins darkish brown. Remainder almost entirely same as female.

VARIATION. The clypeus and mandible except teeth brown. Basal portion of hind tibia dark brown.

Figures

Figs 24–26. Alexeter melanicus sp. nov., holotype, ♀ (GSFGPM). 24. Habitus, lateral view. 25. Head, anterior view. 26. Head, dorsal view. Scale bars: 24 = 1 mm; 25–26 = 0.2 mm.

Figs 27–31. Alexeter melanicus sp. nov., holotype, ♀ (GSFGPM). 27. Mesosoma, lateral view. 28. Mesoscutum and scutellum, dorsal view. 29. Hind tarsomeres, lateral view. 30. Wings. 31. Propodeum, dorsal view. Scale bars: 27, 31 = 0.4 mm; 28–29 = 0.3 mm; 30 = 1 mm.

Figs 32–34. Alexeter melanicus sp. nov., paratype, ♀ (GSFGPM). 32. First and second metasomal tergites, dorsal view. 33. First metasomal tergite, lateral view. 34. Apical portion of metasoma, lateral view. Scale bars: 32 = 0.3 mm; 33–34 = 0.2 mm.