Genus: Megachile Latreille, 1802
Subgenus: Xanthosarus Titus, 1906
Common name: none
Megachile (Xanthosarus) are robust bees with black integument and varying hair color that can be gray, orange-red, yellow, white, or entirely black (Michener 2007; Gonzalez 2008; Praz 2017). Megachile (Xanthosarus) range in body length from 8–18 mm (Michener 2007).
Megachile (Xanthosarus) may be confused with the subgenus Megachile (Phaenosarus) due to the similar structure of the mandible (Michener 2007). Megachile (Xanthosarus) can be differentiated from Megachile (Phaenosarus) by the pubescence on T6 and length of S6. Megachile (Xanthosarus) have erect pubescence to the tip of T6, while Megachile (Phaenosarus) have appressed pubescence on the apical half of T6 (Mitchell 1936). Megachile (Xanthosarus) S6 does not protrude beyond the apex of the tergum, which is short, broad, and apically rounded (Mitchell 1936). In contrast, Megachile (Phaenosarus) S6 extends beyond the apex of the tergum, which is long with a narrowly rounded tip (Mitchell 1936).
Megachile (Xanthosarus) have been observed visiting flowers within the families Asteraceae, Apocynaceae, Campanulaceae, Caprifoliaceae, Cleomaceae, Convolvulaceae, Ericaceae, Fabaceae, Lamiaceae, Loasaceae, Onagraceae, Plantaginaceae, Polygonaceae, and Verbenaceae (Mitchell 1936; Güler and Çağatay 2006).
Megachile (Xanthosarus) nest in pre-existing cavities in wood, sandy soil, and abandoned nests of Anthophora bees (Gonzalez 2008). Females have also been observed digging burrows underground and in decaying wood (Westrich 1989). They use small circular leaves to construct the base of their brood cells (Williams et al. 1986; Krombein and Norden 1995).
There are no known invasives.
Megachile (Xanthosarus) are broadly distributed across the northern hemisphere. They are found in North America, Europe, northern Africa, and Asia. In North America, they can be found from Canada to Mexico (Mitchell 1936; Michener 2007).