The cladistics and higher classification of the Pimpliformes (Hymenoptera: Ichneumonidae)

Abstract

The monophyly of the ichneumonid clade Pimpliformes is established and the phylogenetic relationships of the eight component subfamilies are resolved. The clade (Acaenitinae + (Diacritinae + (Cylloceriinae + (Diplazontinae + Orthocentrinae)))) is the sister‐lineage to the clade (Pimplinae + (Rhyssinae + Poemeniinae)). The Nearctic genus Cressonia Dasch is transferred to the Diacritinae from the Orthocentrinae. Tribes are not recognized in the Acaenitinae as the Coleocentrini (sensu Townes, 1971) is paraphyletic with respect to the Acaenitini. The Cylloceriinae is recognized as comprising three genera, Cylloceria Schiødte, Allomacrus Förster and Sweaterella gen.n. The Orthocentrinae, including the Helictinae of authors, is shown to be monophyletic, but the latter is clearly shown to be paraphyletic if the Orthocentrus genus‐group is excluded. The Pimplinae comprises four monophyletic tribes: the Delomeristini, consisting of Delomerista Förster and Atractogaster Kriechbaumer; the Perithoini trib.n., which includes only Perithous Holmgren (= Hybomischos Baltazar syn.n.); the Pimplini, which includes the Theronia genus‐group as well as the Pimpla genus‐group; and the Ephialtini, which includes the Polysphinctini syn.n., a monophyletic group that previously rendered the restricted Ephialtini paraphyletic. The tribe Delomeristini is the sister‐group to the clade (Ephialtini + (Perithoini + Pimplini)). The subfamily Poemeniinae is recognized as comprising three tribes: the Pseudorhyssini (trib.n.) which includes the single Holarctic genus Pseudorhyssa Merrill; the Rodrigamini (trib.n.) which includes only the Costa Rican genus Rodrigama Gauld; and the Poemeniini. The tribe Pseudorhyssini is the sister‐group to the clade (Rodrigamini + Poemeniini). The phylogenetic inter‐relationships of the genera of Poemeniini are resolved. A new genus from South Africa, Guptella (gen.n.) is described, and Achorocephalus Kriechbaumer is shown to be a synonym of Eugalta Cameron (syn.n.). The evolution of biological traits within the Pimpliformes is discussed with reference to the elucidated phylogeny, and zoogeographic patterns are outlined.

Discovery of Rodrigama Gauld in the Old World, with description of two new species (Hymenoptera, Ichneumonidae, Poemeniinae)

“…Rodrigama can be distinguished from all other poemeniines by either of the following: 1) paired antero-lateral and postero-lateral oblique grooves delimiting a central rhombic area on the second metasomal tergite; 2) fused tergite and sternite of the fi rst metasomal segment and can be readily identifi ed using Wahl & Gauld's (1998) key to genera. Description.…”

“…Th ese are characters unique to R. gamezi. Wahl and Gauld (1998) recognized the spiracles of the fi rst metasomal tergite on promontories as an autapomorphy of the genus. Th is character is shared by all three members of the genus and reconfi rmed here as an autapomorphy.…”

“…Th is character is shared by all three members of the genus and reconfi rmed here as an autapomorphy. Wahl and Gauld (1998) incorrectly coded the epicnemial carina as absent in R. gamezi and were incorrect also in their tribal diagnosis of Rodrigamini, as the epicmnemial carina is present in all three species of the genus. Incidentally, the occipital carina of R. gamezi was coded as complete but it is centrally narrowly incomplete.…”

“…Incidentally, the occipital carina of R. gamezi was coded as complete but it is centrally narrowly incomplete. Wahl and Gauld (1998) hypothesized that the Pimpliformes arose in the north temperate region and diversifi ed into the tropical regions, particularly into the Old World tropics, and latterly into the New World tropics. Th is scenario is well supported by the distributions of Acaenitinae and Rhyssinae (Wahl and Gauld 1998;Yu et al 2005), in which the most derived genera are primarily tropical and the less derived are Holarctic.…”

“…Th e apparently primitive genus, Rodrigama, was known from only a single species, R. gamezi, described from Costa Rica. Th e isolated distribution of this archaic genus in Mesoamerica was anomalous and did not fi t the hypothesis of an Holarctic origin of the Poemeniinae (Wahl and Gauld 1998). Recently, two new species of Rodrigama have been found, one from the Ryukyu Archipelago, at the Oriental and Palaearctic boundary in Japan, and another from Taiwan.…”