Muesebeckidium Krombein, 1969

Lucena, Daercio A. A., Santos-Neto, Pedro E., Zanella, Fernando C. V. & Almeida, Eduardo A. B., 2022, Taxonomic review of the elampine cuckoo wasps from northeastern Brazil (Hymenoptera: Chrysididae), with the description of three new species, Zootaxa 5213 (3), pp. 201-235 : 229

Genus Muesebeckidium Krombein

This genus is one of the rarest South American Elampini and comprises morphologically modified species. The distinctive modified tarsomeres and mesosomal sclerites readily distinguish them from other genera. Diagnostic features include the strongly produced anterolaterally mesopleuron; lateral margin of pronotum bordered with strong carina; female pro- and mesotarsomeres flattened and expanded laterally (often held coiled); and protarsal claw strongly curved. There is still no record of host for this genus. Krombein (1969) suggested that the likely host may be some Pemphredoninae, which nest in twigs and make partitions between the cells and the closing plug of the nest from small, rather loosely packed particles of pith. According to him, the modified tarsomeres of Muesebeckidium would allow it to easily penetrate the nest by displacing the particles that close the entrance, thus giving the parasitoid access to the host cells. Currently, there are three described species in the genus, two from North America and one in South America (only known from Amapá and Pará states, northern Brazil), but only the species in North America have been revised ( Krombein 1969, Bohart & Kimsey 1982). For the first time this genus is reported for northeastern Brazil and a new species is described.