Megachile (Megachile) centuncularis ( Linnaeus, 1758 )

Pritchard, Zoe A., Ivie, Michael A., O’Neill, Kevin M. & Delphia, Casey M., 2025, A faunal treatment of the Megachile (Hymenoptera: Megachilidae) of Montana with a key for their identification, Zootaxa 5683 (1), pp. 1-51 : 31

Megachile (Megachile) centuncularis ( Linnaeus, 1758)

Apis centuncularis Linnaeus, 1758: 575 .

Megachile (Athemois) centuncularis ; Mitchell 1935b.

Megachile (Megachile) centuncularis ; Mitchell 1962: 124; 1980: 25. Butler 1965: 5. Hurd 1979: 2055. Ivanochko 1979: 145. Gonzalez 2008: 35. Scott et al. 2011: 55. Sheffield et al. 2011: 44. Sheffield and Heron 2019: 70.

Diagnosis. The female of M. centuncularis can be identified by its 5-toothed mandibles with evenly deep emarginations between all teeth ( Fig. 7G ), black setae on T6, and yellow to orange scopal setae on S2–6. It is most similar to M. relativa , which has golden setae on T6. The male of M. centuncularis can be identified by its narrow brown to black probasitarsi ( Fig. 8A ), sparse setae on T6, absence of a procoxal spine, and absence of a median tubercle on the clypeus. The male of M. centucularis is most similar to M. lapponica / M. relativa , which has a small triangular median tubercle on the clypeal margin.

Notes. This species is a new state record for Montana, though it is widespread elsewhere in North America. In Montana, it has been sparsely collected in a few western localities ( Fig. 1G ). Photographs, a full morphological description, and notes on the biology of this species can be found in Sheffield et al. (2011) .

Figures

FIGURE 1. County-level distribution of each Megachile species in Montana. Females identified as Megachile latimanus/ Megachile perihirta (and data without recorded specimen sexes) are counted here as M. perihirta as they are not distinguishable from one another in Montana. Males identified as Megachile lapponica/Megachile relativa (and data without recorded specimen sexes) are counted here as M. relativa as they are not distinguishable from one another in Montana. Mitchell county records are included on maps but not in specimen counts. Two specimens did not have county-level localities and are not included in maps but are included in specimen counts.

FIGURE 7. Female Megachile characters. (A–H) Anterolateral view of mandible, (I–N) Lateral view of metasoma, tergites 4–6, (O) Lateral view of tergites on M. dakotensis, and (P) Lateral view of head with pronounced tooth on the posterior genal margin on M. pugnata.

FIGURE 8. Male Megachile characters. (A) Probasitarsus not expanded or excavated ventrally, (B) Probasitarsus widely expanded and excavated ventrally, (C–E) Anterior view of mesobasitarsus and mesotibia, (F) Lateral view of triangular metatarsomeres on M. manifesta, (G) Lateral view of quadrate metatarsomeres on M. wheeleri, (H) Ventral view of procoxal spine, longer than wide, (I) Ventral view of procoxal spine, wide and spatulate, (J–L) Dorsal view of vertex of head: (J) Ocelloccipital distance longer than ocellocular distance, (K) Ocelloccipital distance equal to ocellocular distance, and (L) Ocelloccipital distance shorter than ocellocular distance.