Aneuclis Förster, 1869

Khalaim, Andrey I., 2018, The genera Allophrys Förster and Aneuclis Förster (Hymenoptera: Ichneumonidae: Tersilochinae) of Vietnam, Zootaxa 4378 (3), pp. 414-428 : 421-423

Genus Aneuclis Förster, 1869

Type species: Isurgus rufipes Szépligeti, 1899 (= maritimus Thomson, 1889).

Sathropterus Förster, 1869 (syn. nov.)

Type species: Thersilochus pumilus Holmgren, 1860 .

Aneuclis is a moderately large genus with four Nearctic ( Horstmann 2012), 18 Palaearctic ( Khalaim 2004) and seven Afrotropical species ( Khalaim 2009, 2010). Only two species of Aneuclis occur in the Russian Far East ( Khalaim 2007). The genus is unknown from South Korea and China ( Khalaim & Sheng 2015), as well as from Oriental region.

The small tersilochine genus Sathropterus Förster comprising two species, the cosmopolitan S. pumilus (Holmgren) and Oriental S. secundus Khalaim , is related to Aneuclis differing from the latter by 1) reduced fore wing venation, i.e. completely lacking second recurrent vein (2 m-cu); 2) highly polished frons and vertex, and 3) sinuate apically ovipositor. 1) Reduction of the fore wing venation, i.e. weakly pigmented and hardly discernible to completely lacking second recurrent vein, is known in many tersilochine taxa, including genera Allophrys , Phradis Förster and Tersilochus Holmgren , usually in small-sized species. 2) Smooth frons and vertex is a species level character; species with both smooth and granulate frons and vertex present in most tersilochine genera, including the genus Aneuclis . 3) Apically sinuate ovipositor has appeared independently in several tersilochine genera, e.g. Diaparsis Förster , Probles Förster and Stethantyx Townes , and therefore is considered as a non-generic character.

In spite of the lacking vein 2 m-cu, S. secundus is apparently closely related to A. achterbergi sp. nov. than to S. pumilus because both these species share the following key features—very slender flagellum of antenna, head with occipital carina widely interrupted dorsally, strong notaulus, and deep and long foveate groove of mesopleuron. Thus, the genus Sathropterus is synonymized here with Aneuclis , and its two species, S. pumilus (Holmgren) and S. secundus Khalaim , are transferred to the genus Aneuclis (comb. nov.).

Three species of Aneuclis are found to occur in Vietnam, A. secunda (Khalaim) and two undescribed species. The three Vietnamese species are readily distinguished from their Palaearctic congeners by the head with occipital carina widely interrupted mediodorsally ( Figs 28 , 32, 33 ); A. achterbergi is also distinct in having unusually slender antennal flagellum ( Fig. 27 ) and ovipositor strongly upcurved at extreme apex ( Fig. 31 ), A. devriesi in having apex of ovipositor with two sharp dorsal teeth ( Fig. 36 ), and A. secunda in its straight and extremely short ovipositor ( Fig. 25 ).

In the Palaearctic region, species of Aneuclis have been reared from coleopteran hosts of the families Chrysomelidae , Curculionidae and Nitidulidae on cruciferous plants, and are mainly associated with herbaceous landscapes. Nothing is known about the biology of Vietnamese species.

The widely distributed cosmopolitan species, A. pumilus , is also included to the key. This species has not been reported from Vietnam but it is known from Nepal and India.

Figures

FIGURES 26–31. Aneuclis achterbergi, holotype ♀: 26—habitus, lateral; 27—antennae, lateral; 28—head, dorsal; 29—head and mesosoma, lateral; 30—propodeum, dorsolateral; 31—ovipositor, lateral.

FIGURES 32–36. Aneuclis devriesi, holotype ♀: 32—head and mesoscutum, dorsal; 33—head with antennae, lateral; 34— apex of fore wing; 35—propodeum and base of metasoma, dorsal; 36—apex of ovipositor, lateral.

FIGURES 19–25. Aneuclis pumilus, ♀: 19—apex of fore wing.Aneuclis secunda, ♀: 20—holotype, habitus,lateral; 21—head with antenna, lateral; 22—fore wing; 23—mesosoma and metasoma; 24—propodeum and base of metasoma, dorsal; 25—apex of metasoma with ovipositor.