Phylogeny of thePolysphinctagroup of genera (Hymenoptera: Ichneumonidae; Pimplinae): a taxonomic revision of spider ectoparasitoids
Authors: Gauld Ian D. , Dubois Jacques 
Published: March 2006

Abstract. A cladistic analysis of thePolysphinctagenus‐group (= the ‘Polysphinctini’ of authors), a clade of koinobiont ectoparasitoids of spiders, was undertaken using ninety‐six characters for seventy‐seven taxa (sixty‐five ingroup and twelve outgroup). The genus‐group is monophyletic, nested within the Ephialtini as (Iseropus(Gregopimpla(Tromatobia((Zaglyptus + Clistopyga) + (Polysphinctagenus‐group))))). Within thePolysphinctagenus‐group, the clade (Piogaster + Inbioia) is sister‐lineage to all other genera. The cosmopolitan genusZabrachypusis nonmonophyletic, and has been subdivided into a monophyletic Nearctic/Western PalaearcticZabrachypuss.str. and an Eastern PalaearcticBrachyzapusgen.n., comprisingB. nikkoensis(Uchida)comb.n.,B. tenuiabdominalis(Uchida)comb.n.andB. unicarinatus(Uchida & Momoi)comb.n.An Afrotropical species placed inZabrachypus,Z. curvicauda(Seyrig), belongs toSchizopygacomb.n.The monophyly of the cosmopolitan genusDreisbachiais equivocal, and we consider that species assigned to it are best placed in an expandedSchizopyga(syn.n.). The monobasic Afrotropical genusAfrosphinctais also a synonym ofSchizopyga(syn.n.). The newly delimitedSchizopygais the sister‐lineage ofBrachyzapus, and these two genera form the sister‐lineage ofZabrachypuss.str. as the monophyletic clade (Zabrachypus + (Schizopyga + Brachyzapus)). The Holarctic genusSinarachnais monophyletic if the Palaearctic speciesS. anomala(Holmgren) is excluded and transferred toZatypotacomb.n.The European speciesPolysphincta nielseniRoman belongs to the Palaearctic genusReclinervellus, and (Reclinervellus + Sinarachna) is the sister‐lineage to a monophyletic group of undescribed Asian species herein assigned to a new genus,Chabliseagen.n.All remaining polysphinctine genera form a strongly monophyletic clade, thePolysphinctaclade, although the relationship between this clade and theChabliseaandZabrachypusclades remains an unresolved trichotomy. ThePolysphinctaclade comprises three lineages as an unresolved trichotomy, a monophyleticOxyrrhexis, a major group (‘Polysphincta’ (Ticapimpla(Acrotaphus + Hymenoepimecis))) and anAcrodactylalineage. In the second group, ‘Polysphincta’ is paraphyletic with respect to the other three genera. However, we retain ‘Polysphincta’ as a genus because few species of this very large genus were included in our analysis. We suspect that, when the tropical fauna is better known, it will be possible to subdivide ‘Polysphincta’ into two or more monophyletic taxa. In the third lineage, theAcrodactylalineage, the Holarctic genusAcrodactylais monophyletic if the European speciesA. madida(Haliday) is excluded. Consequently, we erect a new genusMegaetairagen.n.for this species. The monobasic Afrotropical genusPterinopusis the sister‐lineage to the cosmopolitan genusEruga.The very large cosmopolitan genusZatypotaseems to be monophyletic if two New World species,Z. parva(Cresson) andZ. gerardoiGauld, Ugalde & Hanson, are transferred toFlacopimplacomb.n.The expandedFlacopimplais the sister‐group to the Indo‐Australian genusEriostethus, and these two in turn form the sister‐group to (Zatypota + Longitibia). This complex forms an unresolved tetrachotomy with (Pterinopus + Eruga),AcropimplaandMegaetaira. Formal descriptions of all genera are included, together with an illustrated key to the genera. Brief notes are given about the recorded hosts of each genus.