Simon van Noort (Research and Exhibitions Department, Iziko Museums of South Africa)
The ongoing exploration and documentation of the huge diversity of unknown wasp species in South Africa has recently led to the description of new species of rare parasitoid wasp species, several of which are only known from narrow distributional ranges in South Africa. Parasitoid wasps in the platygastrid subfamily Sceliotrachelinae are economically important in that some attack hemipteran pests of citrus. These species are tiny, with the adult wasps often less than a millimetre long.
We described seven new species including representatives of two rare genera that are endemic (i.e. found nowhere else in the world) to South Africa. These two enigmatic genera, Afrisolia and Sceliotrachelus, were previously monotypic, meaning they were each only known from the type specimens of a single species from a single locality.Afrisolia anyskop van Noort & Lahey, 2021, Afrisolia quagga van Noort & Lahey, 2021 and Afrisolia robertsoni van Noort & Lahey, 2021 were added to the genus Afrisolia represented only by the holotype specimen of Afrisolia obesa Masner & Huggert, 1989 collected in Makhanda (Grahamstown) in 1955.
Sceliotrachelus was known only from the two male type specimens of Sceliotrachelus braunsi Brues, 1908 collected in Algoa Bay in 1896. Two new species, Sceliotrachelus midgleyi van Noort, 2021 and Sceliotrachelus karooensis van Noort, 2021, were described from the Eastern and Western Cape, respectively. We also discovered and described the female of S. braunsi, collected in the Kirkwood valley at several sites during our invertebrate survey conducted as part of the SANBI Conservation Farming Project in 2001. Sceliotrachelus species have very unusual morphology, with the toughened wings reduced or held in close apposition to the body, much as in beetle elytra (i.e. creating a protective shield), and have probably lost the ability to fly. Given that most specimens were also collected via leaf litter extraction, pitfall traps, or yellow pan traps, we hypothesize that the evolution of this morphological form is an adaptation to living in leaf-litter. Their biology and host species are unknown.
We also described two charismatic and remarkable new South African species, Parabaeus nasutus van Noort, 2021 and Fidiobia celeritas van Noort & Lahey, 2021. Parabaeus nasutus has a weird nose-like projection on the face, hence the species name, and if this has a sensory function it may be used in the process of host location or mate recognition. We have a very poor knowledge of the biology of most of these genera with no records of which host insects they attack. There are still many species to describe and much work is still needed to figure out their biology and the role that they play in ecological processes and ecosystem service. We developed an interactive online Lucid identification key to the sceliotracheline genera (available on WaspWeb http://www.waspweb.org) to help with the ongoing exploration and documentation of the poorly known African fauna for this group.
The publication in which these species were described:
van Noort S, Lahey Z, Talamas EJ, Austin AD, Masner L, Polaszek A, Johnson NF. 2021. Review of Afrotropical sceliotracheline parasitoid wasps (Hymenoptera, Platygastridae). In: Lahey Z, Talamas E (Eds) Advances in the Systematics of Platygastroidea III. Journal of Hymenoptera Research 87: 115-222. https://doi.org/10.3897/jhr.87.73770
These newly described wasps belong to the extremely diverse insect order Hymenoptera (ants, bees and wasps), which is the focus of entomological research at the Iziko South African Museum.
 | Simon van Noort is Curator of Entomology having conducted research on wasp systematics and evolution at Iziko since 1992. /researcher/simon-van-noort http://www.figweb.org/Research/Laboratories/van_Noort/index.htm https://www.researchgate.net/profile/Simon_Noort |
