Changes in subgeneric classification 1
The species of the subgenus Tergosmia and and the only species of the subgenus Ozbekosmia, Osmia avosetta, share many morphological characteristics (Warncke, 1988b). In addition, the construction of their brood cells is unique in that the cells are composed of two layers of flower petals that sandwich a thin middle layer of mud (Rozen et al., 2010). Furthermore, all Tergosmia species as well as Osmia avosetta exhibit a strong or exclusive preference for Fabaceae as pollen hosts (Müller, 2013). For these reasons, we propose to merge the subgenera Tergosmia and Ozbekosmia into one subgenus Tergosmia comb. nov.