Phylogeny of the ophrynopine clade revisited: review of the parasitoid sawfly genera Ophrella Middlekauff, Ophrynopus Konow and Stirocorsia Konow (Hymenoptera : Orussidae)

Abstract

The rare family Orussidae comprises the only parasitoid sawflies and are sister to the Apocrita, the latter comprising most of Hymenoptera. Because of this, their morphology and relationships have been particularly important for interpreting the morphology of and biological transitions within the order as a whole. Within the Orussidae the ophrynopines are a comparatively diverse clade with a predominantly southern hemisphere distribution. Here, a revised and expanded morphological dataset incorporating several new taxa is used to test ophrynopine relationships and provide further insights into their evolutionary history. The analyses largely corroborate previous results. The distribution pattern and the fossil record indicate that the ophrynopines radiated in the early Cenozoic in the Australasian-Oceanian and the Neotropic regions and later dispersed into the Nearctic, Eastern Palaearctic and Indomalayan regions. The South American genus Ophrella Middlekauff, 1985 is well supported as a monophyletic genus, whereas Ophrynopus Konow, 1897 is paraphyletic with respect to Stirocorsia Konow, 1897. Three new species, Ophrella eldorado Vilhelmsen, sp. nov., Ophrynopus guarani Blank, D.R. Smith & Vilhelmsen, sp. nov., and Ophrynopus rupestris Vilhelmsen, Costa & Alvarenga, sp. nov. are described. Ophrella lingulata Middlekauff, 1985 is treated as a junior synonym of Ophrella amazonica (Westwood, 1874). Stirocorsia is treated as a junior synonym of Ophrynopus. The species Ophrynopus apicalis (Togashi, 2000), Ophrynopus kohli (Konow, 1897), Ophrynopus maculipennis (F. Smith, 1859) and Ophrynopus tosensis (Tosawa & Sugihara, 1934), formerly in Stirocorsia, are transferred to Ophrynopus. Revised keys to the species of Ophrella, Ophrynopus and the genera in the ophrynopine clade are provided. In addition, Orussidae are recorded from Bolivia and French Guiana for the first time.