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Abstract The North American racers (Coluber constrictor) are widely distributed across the Nearctic and numerous studies have demonstrated extensive variation in morphology, ecology, and population genetic structure. Here we take an integrative approach to understand lineage diversification within this taxon by combining genomic sequence capture data, mtDNA sequence data, morphometrics, and ecological niche models. Both the genomic data and mtDNA phylogeographic analyses support five lineages distributed across the range of this species. However, demographic model selection based on these two datasets strongly conflict in both the model of divergence and estimates of timing of lineage divergence. While mtDNA and concatenated genomic data suggest a Miocene origin of these distinct groups, coalescent-based demographic models with the sequence capture data suggest lineage diversification occurred at ~33 kya in allopatry without gene flow. Using linear morphological measurements of head shape we demonstrate that lineages distributed largely east and west of the Mississippi River are distinguishable. Furthermore, ecological niche models demonstrate that lineages distributed in subtropical habitats have environmental niche space that is significantly differentiated from lineages distributed across the continent. Taken together, these results suggest that ecology is an important axis of lineage divergence within this group and that more fine-scale analyses may find even greater differentiation between the populations identified here. This abstract translated to Spanish is avaliable in the Supporting Infromation section (Este resumen traducido al español está disponible en la sección, Supporting Infromation).
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Integrative approach resolves the taxonomy of Eulaema cingulata (Hymenoptera, Apidae), an important pollinator in the Neotropics
Species delimitation is a rich scientific field that often uses different sources of data to identify independently evolving lineages that might be recognized as species. Here, we use an integrative approach based on morphometrics, COI-barcoding, and phylogenomics using ultraconserved elements (UCEs) to investigate whether the orchid bee species Eulaema cingulata (Fabricius, 1804) and E. pseudocingulata Oliveira, 2006 represent a single variable taxon or two different species. We analyzed 126 specimens across the geographical range of these nominal species to test species hypotheses using the general lineage concept. We found substantial overlap in wing and head morphometrics, and both taxa form one phylogenetic lineage based on COI mitochondrial and UCE data. Our results support the recognition of both forms as members of the same evolutionary unit and E. pseudocingulata is herein recognized as a junior synonym of E. cingulata .
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- Award ID(s):
- 2127744
- PAR ID:
- 10428105
- Date Published:
- Journal Name:
- Journal of Hymenoptera Research
- Volume:
- 94
- ISSN:
- 1070-9428
- Page Range / eLocation ID:
- 247 to 269
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3897/jhr.94.91001
