Resumen

ROIG-ALSINA, Arturo. Joergensenella, a new subgenus of Neotropical Megachile (Hymenoptera: Megachilidae), with a key to Argentinean Megachile with specialized facial pollen-harvesting hairs. Rev. Mus. Argent. Cienc. Nat. [online]. 2020, vol.22, n.1, pp.21-46. ISSN 1853-0400.

A new subgenus of Megachile, Joergensenella n. subg., is described for the Neotropical Region. It is distributed in Argentina, southern Brazil, and Uruguay. Males run to Chrysosarus in available keys to subgenera of Megachile, and have been included as such in recent catalogs, while the females run in the keys, and have been included in catalogs, as Dasymegachile or Cressoniella. Association of sexes for all the species are presented for the first time. Besides the type species, M. joergenseni Friese, the following are included in the subgenus Joergensenella: M. bruneriella Cockerell, M. una Vachal, M. lujanense n. sp. (from Mendoza, Argentina), M. fidalgoi n. sp. (from Jujuy, Argentina), M. puntana n. sp. (from San Luis and Tucumán, Argentina), and M. yana n. sp. (from La Rioja, Argentina). Females of one of the species included, M. (Joergensenella) una, bear specialized hairs on the face for the collection of pollen from nototribic flowers. A key is presented to separate this species from other two Megachile in Argentina with a similar specialization: M. (Dasymegachile) schwimmeri Engel, and M. (Cressoniella) boliviensis Friese.

Palabras clave : Megachile; Leafcutter bees; New subgenus; Facial pollen-collecting apparatus.