A survey of megachilid bees of the Nakhchivan Autonomous Republic of Azerbaijan, with description of a new species of Pseudoanthidium Friese, 1898 (Hymenoptera, Megachilidae)

A list of 184 species of megachilid bees from 19 genera and five tribes is reported for the Nakhchivan Autonomous Republic of Azerbaijan. The list is based on 2,099 examined specimens identified to 171 species; 13 additional species are known on the base of literature records only. A new species, Pseudoanthidium (Exanthidium) astafurovae Fateryga, Maharramov & Proshchalykin, <b>sp. nov.</b>, is described. Anthidium (Anthidium) akanthurum Nadimi & Talebi, 2014, <b>sp. resurr.</b>, is recognised as a distinct species, not a synonym of A. (A.) gussakovskiji Mavromoustakis, 1939. Nineteen species are new to Azerbaijan: A. (A.) akanthurum, Chelostoma (Foveosmia) foveolatum (Morawitz, 1868), Coelioxys (Allocoelioxys) argenteus Lepeletier de Saint-Fargeau, 1841, C. (A.) obtusus Pérez, 1884, C. (Coelioxys) quadridentatus (Linnaeus, 1758), Heriades (Michenerella) punctulifera Schletterer, 1889, Hoplitis (Alcidamea) brachypogon (Pérez, 1879), H. (A.) campanularis (Morawitz, 1877), H. (Anthocopa) mocsaryi (Friese, 1895), Megachile (Eutricharaea) anatolica Rebmann, 1968, M. (Megachile) genalis Morawitz, 1880, <i>Metadioxys graeca</i> (Mavromoustakis, 1963), Osmia (Helicosmia) breviata Warncke, 1988, O. (H.) clypearis acuta Warncke, 1988, O. (Osmia) scheherazade Peters, 1978, O. (Tergosmia) rhodoensis (van der Zanden, 1983), Protosmia (Nanosmia) magnicapitis (Stanek, 1969), Pseudoanthidium (Pseudoanthidium) rhombiferum (Friese, 1917), and P. (P.) syriacum Kasparek, 2024. <i>Metadioxys formosus</i> (Morawitz, 1875) and Coelioxys (Allocoelioxys) sogdianus Morawitz, 1875 are excluded from the fauna of Azerbaijan. The number of species of Megachilidae known from Azerbaijan is increased to 196.