Description of three new genera and four new species of Neanastatinae (Hymenoptera, Eupelmidae) from Baltic amber, with discussion of their relationships to extant taxa

Abstract

Aspidopleura baltica gen. n. and sp. n., Brevivulva electroma gen. n. and sp. n., Neanaperiallus masneri gen. n. and sp. n., and Metapelma archetypon sp. n. are described in Neanastatinae (Chalcidoidea, Eupelmidae) from Baltic amber. New information is given on the morphology of Eopelma Gibson, Lambdobregma Gibson, Metapelma Westwood and Neanastatus Girault, the four extant genera previously classifi ed in Neanastatinae, and the extinct and extant taxa are compared with other Chalcidoidea for hypotheses of character evolution and phylogenetic relationships. Structural features of Neanaperiallus and Aspidopleura indicate that except for a greatly enlarged acropleuron the groundplan structure of Neanastatinae was similar to male Eupelminae or some Cleonyminae (Pteromalidae). Furthermore, classifi cation of Neanaperiallus in Neanastatinae results in no putative autapomorphies to support monophyly of the subfamily. Some features of Encyrtidae, Tanaostigmatidae and Neanastatinae suggest that the taxa may have had a common ancestor, therefore rendering Eupelmidae paraphyletic. A key to the seven recognized genera and a revised diagnosis of Neanastatinae are given.

The extinct Baltic amber genus Propelma Trjapitzin, a valid genus of Neanastatinae (Hymenoptera, Eupelmidae)

“…Mesoscutellar-axillar complex (Figs 6, 7, 9) with axillae transverse-triangular with contiguous inner angles, convex with abruptly angled, oblique, strongly crenulate posterior surfaces forming scutoscutellar sutures; mesoscutellum similarly convex as axillae, teardrop-shaped (cf. Gibson 2009, fig. 13), posteriorly tapered with apex curved down as short hook-like medial protrusion (Fig.…”

“…Propelma is assigned to Neanastatinae based on pronotal structure, mesopectus posteroventrally abutting the mesocoxal bases without a membranous region anterior to each coxa, and mesotarsal peg pattern, all of which are diagnostic of the subfamily (Gibson 1989, 2009). The scutoscutellar suture is also crenulate similar to extant and extinct species of Metapelma (Gibson 2009, fig.…”

“…13) and some species of Lambdobregma (Gibson 2009, fig. 15) (extant) as well as Aspidopleura (Gibson 2009, fig. 49) and Brevivula (Gibson 2009, fig.…”

“…15) (extant) as well as Aspidopleura (Gibson 2009, fig. 49) and Brevivula (Gibson 2009, fig. 39) (extinct), and the scutellum apically is curved ventrally into a small hook-like process over the metanotum similar to extant species of Lambdobregma (Gibson 2009, figs 15, 16) and Neanastatus (Gibson 2009, fig.…”

“…Propelma keys to couplet 6 ( Brevivula and Lambdobregma ) using the key to genera of Neanastatinae in Gibson (2009). It differs from both genera in having the fore wing uniformly setose (Fig.…”