Heterischnus Wesmael, 1859

Pos, Davide Dal, Claridge, Brandon, Diller, Erich, Noort, Simon Van & Giovanni, Filippo Di, 2023, Still counting: new records, nomenclatural notes, and three new species of Phaeogenini (Hymenoptera, Ichneumonidae, Ichneumoninae) from the Afrotropical region, European Journal of Taxonomy 868, pp. 1-71 : 38-39

Genus Heterischnus Wesmael, 1859

Heterischnus Wesmael, 1859: 83 . Type species: Ichneumon pulex Müller, 1776 , by monotypy.

[ Aethiopischnus ] Heinrich, 1936: 244. Nomen nudum.

Aethiopischnus Heinrich, 1938: 127 . Type species: Aethiopischnus olsoufieffi Heinrich, 1938 , by original designation. Synonymized by Townes & Townes (1951: 278) under Rhexidermus Förster, 1869 .

Ischnopsidea Viereck, 1914: 77 . Type species: Ischnus thoracicus Gravenhorst, 1829 , by original designation. Synonymized by Townes (1944: 305) under Rhexidermus Förster, 1869 .

Posocentrus Provancher, 1875: 272 . Type species: Posocentrus huardi Provancher, 1875 , by monotypy. Synonymized by Townes (1944: 305) under Rhexidermus Förster, 1869 .

Rhexidermus Förster, 1869: 192 . Type species: Rhexidermus japonicus Ashmead, 1906 , by subsequent monotypy by Ashmead (1906: 171). Synonymized by Perkins (1959: 77).

Diagnosis

The unidentate and falcate mandibles set Heterischnus Wesmael, 1859 apart from all the other Afrotropical genera of Phaeogenini , except for Lusius , from which it can be distinguished by the presence of vein 3rsm (areolet closed) in the fore wing and the abscissa of CU in the hind wing. Additionally, the genus can be separated from other genera by the following combination of characters: (1) clypeus separated from face by clupeal suture; (2) basal flagellar segments slender and long; (3) vertex long and slightly convex behind ocelli; (4) hypostomal carina joining occipital carina distinctly at or above mandibular base; (5) epicnemial carina strongly raised ventrally and flexed over the base of the fore coxae; (6) notauli distinct anteriorly, deep and long; (7) tarsal claws simple; (8) gastrocoeli nearly indistinct to deep, thyridia wide; (9) ovipositor extending relatively strongly beyond apex of metasoma ( Perkins 1959; Selfa & Diller 1994; Rousse et al. 2013; Claridge 2021b).

Remarks

Heterischnus Wesmael, 1859 occurs in the Afrotropical, Nearctic, and Palearctic regions ( Yu et al. 2016; Claridge 2021b). Previous to this contribution, 5 species were recorded in the Afrotropic ( Rousse et al. 2013; Yu et al. 2016), but, with H. mkomazi Rousse & van Noort, 2013 being herein transferred to the genus Nesostenodontus (see below for the complete analyses), the current number of Afrotropical species is 4, namely: H. africanus ( Heinrich, 1936) , H. karusi Schönitzer, 1999 , H. mfongosi Rousse & van Noort, 2013 and H. olsoufieffi ( Heinrich, 1938) . As a result of the transfer, the genus is no longer recorded for Senegal ( Table 1).

Remarks

Despite being currently a synonym of Heterischnus , Aethiopischnus requires a focused commentary to resolve some nomenclatural issues. Aethiopischnus firstly appeared in Heinrich (1936: 244) without being accompanied by any formal description. The genus name served only to accommodate the description of a new species, Aethiopischnus africanus . Later on, Heinrich (1938: 127) introduced the name Aethiopischnus again as “ gen. nov. ” providing this time an adequate description and designating Aethiopischnus olsoufieffi as the type species. Townes & Townes (1973: 221) acknowledged the two names ( Aethiopischnus Heinrich, 1936 and Aethiopischnus Heinrich, 1938 ) and placed them as a synonym of Heterischnus . Yu & Horstmann (1997: 489) deemed Aethiopischnus Heinrich, 1936 an unavailable name without providing any discussion for their action. According to ICZN (1999: article 13.1.1), to be available a name proposed after 1930 needs to be accompanied “ by a description or definition that states in words characters that are purported to differentiate the taxon. ”. Because of the lack of a proper description, the genus name Aethiopischnus Heinrich, 1936 is deemed a nomen nudum, and therefore unavailable. Aethiopischnus Heinrich, 1938 is the available name (even though invalid) in accordance with Yu & Horstmann (1997: 489).