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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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Systematics and biogeography of a Sunda-Papuan snake lineage (Natricidae: Tropidonophis Jan 1863)
Abstract Sunda-Papuan keelback snakes (Serpentes: Natricidae: Tropidonophis Jan 1863) include 20 species distributed from the Philippines south-east through the Moluccas to New Guinea and Australia. Diversity of this insular snake lineage peaks on the island of New Guinea. Previous phylogenetic studies incorporating Tropidonophis have been limited to multi-locus Sanger-sequenced datasets with broad squamate or family-level focus. We used a targeted-sequence capture approach to sequence thousands of nuclear ultraconserved elements (UCEs) to construct the most comprehensive sequence-based phylogenetic hypothesis for this genus and estimate ancestral biogeography. Phylogenies indicate the genus is monophyletic given recent taxonomic reassignment of Rhabdophis spilogaster to Tropidonophis. All UCE phylogenies recovered a monophyletic Tropidonophis with reciprocally monophyletic Philippine and New Guinean clades. Divergence dating and ancestral range estimation suggest dispersal to New Guinea from the Philippines to have occurred during the Mid-Miocene via the Oceanic Arc Terranes. From Late Miocene into the Pliocene the genus experienced rapid diversification from orogeny of the New Guinean Central Cordillera from Oceanic Arc Terrane accretion on the northern boundary of the Sahul Shelf. Future collecting of missing taxa from the Moluccas and Indonesian Papua will better the understanding of non-volant faunal biogeography and diversification in this tectonically complex Pacific arena.
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- PAR ID:
- 10502252
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Zoological Journal of the Linnean Society
- Volume:
- 202
- Issue:
- 4
- ISSN:
- 0024-4082
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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