Taxonomic notes on Megalopta Smith, 1853 (Hymenoptera: Halictidae: Augochlorini) with a synopsis of the species in the state of Minas Gerais, Brazil

Abstract

There are twenty-seven described species in the nocturnal bee-genus Megalopta Smith, 1853 (Hymenoptera: Halictidae); of these, 10 were recorded from Brazil but none in the Brazilian state of Minas Gerais. Here, five species of Megalopta are recorded for this state, two of them described as new. Four of these species belong in the subgenus Megalopta Smith s.str.: M. (M.) aegis (Vachal, 1904), M. (M.) amoena (Spinola, 1853), M. (M.) sodalis (Vachal, 1904) and M. (M.) guimaraesi sp.n., and one: M. atlantica sp.n., belongs to the subgenus Noctoraptor Engel, Brooks & Yanega, 1997, which is recorded for the first time for Brazil.A key for the identification of these five species is provided. Based on the examination of the types of species described by H. Friese and J. Vachal, M. ecuadoria Friese, 1926 and M. ochrias (Vachal, 1904) are proposed to be junior synonyms of M. amoena; and M. aethautis (Vachal, 1904) is proposed to be a junior synonym of M. fornix (Vachal, 1904). Lectotypes are designated for M. aeneicollis Friese; 1926 , M. armata Friese, 1926 M. boliviensis Friese, 1926; M. cuprea Friese, 1911; and M. sulciventris Friese, 1926. Evidence that Megalopta s.str. is rendered paraphyletic by the recognition of the subgenus Noctoraptor is presented and the potential use of aromatic baits for the inventory of local Megalopta faunas is discussed.

The Colour and the Shape: Morphological Variation on a Facultatively Eusocial Bee Augochlora (Augochlora) amphitrite (Schrottky)

“…The swollen gena was already discussed as an important feature to identify macrocephalic forms in eusocial species of Augochlorini (Sakagami & Moure 1965;Santos & Silveira, 2009). There is no study on head musculature for the tribe, but in ants the major forms with enlarged heads have developed muscles, including those for moving the mandibles (Lillico-Ouachour et al, 2018).…”

“…Other lineages of Augochlorini have also intraspecific variation in head morphology. In Megalopta, another group with wood nesting facultative eusocial species, the gena show different degrees of swelling and a genal projection of variable length is present (Santos & Silveira, 2009). In this bee tribe, the most remarkable cases of cephalic polymorphism come from the Rhinocorynura group (Gonçalves & Melo, 2012).…”

Updating the taxonomy of the bee genusMegalopta(Hymenoptera: Apidae, Augochlorini) including revision of the Brazilian species

“…Megalopta is a speciose genus within the bee tribe Augochlorini, with distribution from southern Brazil (state of Santa Catarina) to the state of Sinaloa, in Mexico (Michener 2007;. Currently, the genus has 30 valid species, most of them inhabiting the Amazon basin (Moure 2007;Santos and Silveira 2009;. Dating based on molecular analyses estimates that the genus diversification probably started in the Tertiary, with a range between 15 and 30 mya (Danforth et al 2004;Tierney et al 2012).…”

“…The main studies on the taxonomy of the genus are: Cockerell (1900, Ducke (1908Ducke ( , 1910, Schrottky (1906), , , Friese ( ,1923, Moure (1943Moure ( , 1958, Michener and Moure (1964), Engel et al (1997), Hinojosa-Diaz and Engel (2003), , Santos and Silveira (2009) and .…”

“…Specimens were photographed using a Leica DFC 500 camera attached to a Leica MZ16 stereomicroscope (Leica, Germany), and images were treated using the software Auto-Montage Pro (Syncroscopy) of the Projeto Taxon line, Rede Paranaense de Coleções Biológicas da Universidade Federal do Paraná (DZUP). Some of the photographs presented here appeared previously in Santos and Silveira (2009).…”