European cuckoo bees of the tribe Dioxyini (Hymenoptera, Megachilidae): distribution, annotated checklist and identification key Author Bogusch, Petr https://orcid.org/0000-0002-4554-6141 Department of Biology, Faculty of Science, University of Hradec Kralove, Rokitanskeho 62, CZ- 500 03 Hradec Kralove, Czech Republic bogusch.petr@gmail.com text Journal of Hymenoptera Research 2023 2023-07-25 96 599 628 http://dx.doi.org/10.3897/jhr.96.104957 journal article http://dx.doi.org/10.3897/jhr.96.104957 1314-2607-96-599 16A4A16551854C89960D614A74E6D394 A32C8DF9AEC35B35AC4D32F6EEB83552 Paradioxys pannonicus ( Mocsary ) Paradioxys pannonica Mocsary , 1894: 35. Diagnosis. Middle-sized species, body length 7-10 mm. The only species of the genus within Europe. Typical by the characteristics of the genus, similar to species of the genus Dioxys . It is uniform in appearance, females black with first four metasomal terga entirely reddish amd males' whole metasoma reddish. Legs are also reddish (Fig. 19A, B ). Metasoma of females have narrow apical bands of whitish short appressed hair; similar hairs are also distributed on the first metasomal terga laterally. The metasoma of males have bands of whitish short appressed hair that are sparse and barely visible. The male body has a tomentum-like light brown or yellowish hair. Females have a narrowed T6 and a very long and sharp S6, projecting behind the T6 (Fig. 19C ). In males, the end of the metasoma is straight, not curved (Fig. 19F ), and the apex of S4 has two prominent toothlike projections, which are larger than in males of Dioxys (Fig. 19D, E ). Figure 19. Paradioxys pannonicus A female, dorsal view B male, dorsal view C female, last metasomal segments, dorsal view D male, metasoma, ventral view E male, last metasomal segments, ventral view F male, last metasomal segments, dorsal view. Red scale bars represent the length of 1 mm, blue scale bars 100 µm . Distribution. This species was described from Hungary and is a Euro-Asiatic species that occurs from central Europe to the north-eastern Mediterranean (Fig. 20 ) and outside of Europe towards the Middle East and Iran ( Popov 1936 ; Warncke 1977 ; Bogusch et al. 2007 ; Gusenleitner et al. 2012 ; Ascher and Pickering 2023 ). Figure 20. Paradioxys pannonicus , distribution in Europe. Biology and hosts. This species attacks nests of species of the family Megachilidae . Scheuchl and Willner (2016) reported Chalicodoma hungarica ( Mocsary ) as its main host, and Gusenleitner et al. (2012) included C. parietina as its host. Conservation status. Nieto et al. (2014) classified this species as DD - data deficient. This is a typical Pannonian species occurring in the Pannonian basin. However, there is a lack of records from recent years, and the most recent finds are from the 1970s and 1980s. We suppose this species is CR - critically endangered in Europe.