Botsvania, Rasnitsyn & Brothers, 2007

Rasnitsyn, Alexandr P. & Brothers, Denis J., 2007, Two new hymenopteran fossils from the mid-Cretaceous of southern Africa (Hymenoptera: Jurapriidae, Evaniidae), African Invertebrates 48 (1), pp. 193-202 : 198-200

Family Evaniidae Latreille, 1802

Genus Botsvania gen. n.

Figs 5, 6

Etymology: The genus name is derived from Botswana and the genus Evania ; gender feminine.

Type species: B. cretacea sp. n., by present designation.

Diagnosis: Antenna 15- or 16-segmented, attached near lower orbits. Mesothoracic prescutum and scutellum both triangular; lateral contour of propodeum smoothly rounded, with dorsal surface comparatively long (more than one third as long as posterior surface). Hind leg about as long as in some extant ensign wasps (hind femur as long as head and mesosoma combined). Vein RS+M originating much higher along basal vein than in most other Mesozoic evaniids. Petiolar (1 st metasomal) segment subcylindrical, comparatively short and wide (length about 3 times width).

Species included: Type species only.

Taxonomic position: The position of the new genus within Evaniidae is supported by the high attachment of the metasoma on the propodeum (synapomorphy of Evanioidea) combined with the elbowed antenna (unique for Evaniidae in the superfamily), the close association of the head with the mesosoma, the absence of the medial mesoscutal line (present in Praeaulacidae ), the position of RS+M well above the mid-height of the basal vein (not above mid-height in Gasteruptiidae s.l.), and the short subcylindrical petiole (conical if modified as a petiole in Gasteruptiidae s.l., long and subcylindrical in Andreneliidae ). Within Evaniidae , the new genus combines some outstanding plesiomorphies (lower attachment of antenna, as in Evanioidea other than Evaniidae ; triangular prescutum and scutellum, as in Praeaulacidae ; and smoothly curved propodeum with comparatively long dorsal surface) with various apomorphies. The antenna with fewer than 25 segments (the number in Mesevania Basibuyuk & Rasnitsyn, 2000 ), the forewing crossveins 2–3r–m and 2m –cu lost as tubular veins, and the short ovipositor suggest monophyly with all evaniids other than Mesevania , while the 15- or 16-segmented antenna makes it possibly the sister group of all Evaniidae above Mesevania (fewer than 14 segments in all others; Basibuyuk et al. 2002, Deans et al. 2004). At the same time, the high position of RS+M suggests monophyly with higher Evaniidae , that is, with all Cainozoic genera plus the Late Cretaceous (Turonian) Newjersevania Basibuyuk, Quicke & Rasnitsyn, 2000 . The remaining Cretaceous genera either have RS+M meeting the basal vein near its mid-height ( Mesevania , Lebanevania Basibuyuk, Rasnitsyn, Fitton & Quicke, 2002 , Proparevania Deans in Deans et al. 2004, and Grimaldivania Basibuyuk, Fitton, Rasnitsyn & Quicke, 2000b ), or have their wing venation highly modified (the closely related Cretevania Rasnitsyn, 1975 , Procretevania Zhang & Zhang, 2000 , and Eovernevania Deans in Deans et al. 2004 have the basal vein displaced far basad, with the position of RS+M secondarily modified and variable). The comparatively long, narrow, subcylindrical petiole with no apparent borderline between tergum and sternum suggests monophyly with all Evaniidae except Lebanevania and Grimaldivania , in both of which it is short, stout and conical; the tergum and sternum are clearly delimited in Lebanevania . The general habitus with a short body and very long hind legs indicates a synapomorphy with the highest extant evaniids. Thus the phylogenetic indications are strikingly contradictory and might only be balanced by a cladistic analysis. However, the number of characters available is evidently too low to expect any meaningful results from a rigorous cladistic procedure (cf. the results obtained for the better-preserved amber fossils of Lebanevania and Mesevania ; Basibuyuk et al. 2002, figs 9–14). Thus we can only conclude that the new genus has an undefined position among the lower (Cretaceous) Evaniidae .

Remarks: Botsvania is about coeval with Grimaldivania and Newjersevania from the Turonian of New Jersey in eastern North America. Those genera are represented by three species, and nothing similar to Botsvania has been found there. Similarly, seven other specimens of Evanioidea have been found at Orapa ( Brothers & Rasnitsyn 2003) , and not one of them is similar to Grimaldivania or Newjersevania . Also, nothing closely related has been found in numerous Late Cretaceous hymenopteran assemblages of Siberia; Evaniidae are represented there by Cretevania ( Rasnitsyn, 1980) . The older (Hauterivian through Albian) Evaniidae from the Lebanese and Burmese ambers are either unlike or ( Protoparevania ) only superficially similar to Botsvania ( Basibuyuk et al. 2000 a, 2002; Deans et al. 2004). The difference in mean size between impression fossils (from Orapa) and amber inclusions (from New Jersey and many Siberian localities) that often hinder comparison of respective fossil assemblages ( Rasnitsyn, 1980), is of less importance in this particular case, because Newjersevania casei Basibuyuk, Quicke & Rasnitsyn, 2000 is even larger than B. cretacea , and small fossils less than 2 mm long are not uncommon in the Orapa assemblage. This makes it possible to conclude that the Late Cretaceous fauna of Evaniidae was diverse and zoogeographically specific, although not very rich at each particular place.

Figures

Figs 5, 6. Botsvania cretacea Rasnitsyn & Brothers, gen. et sp. n.: (5) Holotype, BP/2/26835/1; (6) Drawing, with composite forewing below. Antenna: S – scape, P – pedicel, 1–12 – flagellomeres; wing veins labelled conventionally. Scale bar = 1 mm.