Revision of the species-group of Mischocyttarus (Omega) filiformis (de Saussure 1854), with description of three new species (Hymenoptera, Vespidae).

A taxonomic revision of the species-group related to M. filiformis (Saussure 1854) is presented along with an identification key to species. After Richards (1978) and following the rearrangement of the subgenus Omega de Saussure by Silveira (2008), the species-group considered herein included three species in addition to M.

Update to the knowledge of the social wasps of the Brazilian state of Amapá based on the vespid collection of the Amapá Research Institute (IEPA) (Hymenoptera, Vespidae, Polistinae).

Information is presented concerning specimen records of polistine social wasps in the state of Amapá, Brazil, in the years from 1904 to 2016, mainly coming from the IEPA and MPEG collections. Spatial distribution of records and of the total collecting effort were analyzed with respect to general landscape aspects of the region, such as vegetation types, hydrography, road infrastructure and the state network of conservation unities. The number of social wasp species registered for Amapá is now 144, with 17 new records of species for the Guiana Shield, and nine species not yet described.