Hitting an Unintended Target: Phylogeography of Bombus brasiliensis Lepeletier, 1836 and the First New Brazilian Bumblebee Species in a Century (Hymenoptera: Apidae)

Abstract

This work tested whether or not populations of Bombus brasiliensis isolated on mountain tops of southeastern Brazil belonged to the same species as populations widespread in lowland areas in the Atlantic coast and westward along the Paraná-river valley. Phylogeographic and population genetic analyses showed that those populations were all conspecific. However, they revealed a previously unrecognized, apparently rare, and potentially endangered species in one of the most threatened biodiversity hotspots of the World, the Brazilian Atlantic Forest. This species is described here as Bombus bahiensis sp. n., and included in a revised key for the identification of the bumblebee species known to occur in Brazil. Phylogenetic analyses based on two mtDNA markers suggest this new species to be sister to B. brasiliensis, from which its workers and queens can be easily distinguished by the lack of a yellow hair-band on the first metasomal tergum. The results presented here are consistent with the hypothesis that B. bahiensis sp. n. may have originated from an ancestral population isolated in an evergreen-forest refuge (the so-called Bahia refuge) during cold, dry periods of the Pleistocene. This refuge is also known as an important area of endemism for several animal taxa, including other bees. Secondary contact between B. bahiensis and B. brasiliensis may be presently prevented by a strip of semi-deciduous forest in a climate zone characterized by relatively long dry seasons. Considering the relatively limited range of this new species and the current anthropic pressure on its environment, attention should be given to its conservation status.

Past, present and future distributions of bumblebees in South America: Identifying priority species and areas for conservation

“…According to model predictions, annual mean temperatures between 25 and 30°C favour the occurrence of B. transversalis , while higher probability of B. bellicosus occurrence was recorded between 15 and 20°C. Similarly, B. brasiliensis is the only neotropical bumblebee commonly found on mountaintops and recorded at elevations above 1,800 m (Moure & Sakagami, 1962; Santos‐Júnior, Santos, & Silveira, 2015). The generated response curves show a higher species probability of occurrence at elevations above 900 m.…”

Forest Matrix Fosters High Similarity in Bee Composition Occurring on Isolated Outcrops Within Amazon Biome

“…All collected bees were identified by specialists (B.W.T.C., J.E.S.J., and R.L.R.) with the support of a stereo microscope and taxonomic keys (e.g., Silveira et al 2002 , Nemésio and Ferrari 2011 , Santos Júnior et al 2015 ) and deposited in the Museu Paraense Emílio Goeldi (MPEG, Pará, Brazil).…”

A phylogenetic study of the Thygater‐Trichocerapis group and new scopes for the subgenera of Thygater Holmberg, (Hymenoptera, Apidae)

“…The PCR products were visualized in agarose gels at a concentration of 0.8%. The products of positive reactions were purified through polyethyleneglycol 20% (Santos Júnior et al , ). The purified PCR products were sequenced in both directions with the same primers used in PCR, using the BigDye terminator sequencing kit (Applied Biosystems, Waltham, Massachusetts) and analysed with an ABI 3130xl (Applied Biosystems).…”

“…The PCR was performed in a thermocycler with the following programme: 5 min of denaturation at 94 ∘ C, followed by 35 cycles of 30 s at 94 ∘ C, 40 s at 48 ∘ C, 1 min at 72 ∘ C and a final extension of 10 min at 72 ∘ C. The PCR products were visualized in agarose gels at a concentration of 0.8%. The products of positive reactions were purified through polyethyleneglycol 20% (Santos Júnior et al, 2015). The purified PCR products were sequenced in both directions with the same primers used in PCR, using the BigDye terminator sequencing kit (Applied Biosystems, Waltham, Massachusetts) and analysed with an ABI 3130xl (Applied Biosystems).…”