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Abstract The northern temperate genusDracocephalumconsists of approximately 70 species mainly distributed in the steppe‐desert biomes of Central and West Asia and the alpine region of the Qinghai‐Tibetan Plateau (QTP). Previous work has shown thatDracocephalumis not monophyletic and might includeHyssopusandLallemantia. This study attempts to clarify the phylogenetic relationships, diversification patterns, and the biogeographical history of the three genera (defined asDracocephalums.l.). Based on a sampling of 66 taxa comprising more than 80% from extant species ofDracocephalums.l., morphological, phylogenetic (maximum parsimony, likelihood, and Bayesian inference based on nuclear ITS and ETS, plastidrpl32‐trnL,trnL‐trnF,ycf1, andycf1‐rps15, and two low‐copy nuclear markersAT3G09060andAT1G09680), molecular dating, diversification, and ancestral range estimation analyses were carried out. Our results demonstrate that bothHyssopusandLallemantiaare embedded withinDracocephalumand nine well‐supported clades can be recognized withinDracocephalums.l. Analyses of divergence times suggest that the genus experienced an early rapid radiation during the middle to late Miocene with major lineages diversifying within a relatively narrow timescale. Ancestral area reconstruction analyses indicate thatDracocephalums.l. originated in Central and West Asia and southern Siberia, and dispersed from Central and West Asia into the QTP and adjacent areas twice independently during the Pliocene. The aridification of the Asian interior possibly promoted the rapid radiation ofDracocephalumwithin this region, and the uplift of the QTP appears to have triggered the dispersal and recent rapid diversification of the genus in the QTP and adjacent regions. Combining molecular phylogenetic and morphological evidence, a revised infrageneric classification ofDracocephalums.l. is proposed, which recognizes nine sections within the genus.
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The Phyllotis xanthopygus complex (Rodentia, Cricetidae) in central Andes, systematics and description of a new species
Abstract PhyllotisWaterhouse 1837 is one of the most studied genera of South American cricetid rodents. As currently understood, it includes 20 small to medium‐sized species of predominantly rocky habitats. Among them, populations of the yellow‐rumped leaf‐eared mouse, traditionally referred toP. xanthopygus(Waterhouse 1837), are the most widely distributed, extending from central Peru to southern Chile and Argentina. Based mostly on molecular evidence, previous studies suggested thatP. xanthopygusconstitutes a species complex, being characterized by geographically structured and genetically divergent clades. In this work, we compare the molecular phylogenetic hypothesis for populations distributed on the eastern slopes of the central Andes with morphometric evidence using univariate and multivariate analyses. Quantitative morphological and molecular evidence suggests that at least four nearly cryptic species of theP. xanthopyguscomplex occur from southern Bolivia to west‐central Argentina. Three of these taxa have available names; one of them,P. caprinus, is currently recognized to the species level; the other two, the clades ofP. x. posticalis‐P. x. rupestrisandP. vaccarum, are both recognized as subspecies ofP. xanthopygus. The remaining taxon represents a new species distributed in the west‐central Andes of Argentina. We discuss our morphological results in the light of other sources of evidence (e.g. qualitative and quantitative state characters, genetic and phylogenetic studies, and cytogenetic data) and name the new species asP. pehuenche, honouring the original native people that historically inhabited west‐central Andes of Argentina.
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- PAR ID:
- 10450130
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Zoologica Scripta
- Volume:
- 50
- Issue:
- 6
- ISSN:
- 0300-3256
- Page Range / eLocation ID:
- p. 689-706
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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