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.
New Guinea is the largest tropical island in the world and hosts immense endemic biodiversity. However, our understanding of how the gradual emergence of the terrestrial ecosystems of the island over the last 40 Myr has generated this biological richness is hampered by poorly documented species diversity and distributions. Here, we address both these issues through an integrative taxonomy and biogeographical approach using Hylophorbus, a New Guinea-endemic genus of frogs with 12 recognized species. We delimited candidate species by integrating mitochondrial DNA, nuclear DNA, and bioacoustics, then investigated their evolutionary history. Our results suggest that the current taxonomy of the genus misses true species diversity by ≥3.5-fold. Nevertheless, most candidate species (27) remain unconfirmed because of missing data, whereas five were identified unambiguously as undescribed (we describe three of these formally). Time-calibrated phylogenetic analyses suggest that Hylophorbus diversification began ~9 Mya in the northern or eastern portion of New Guinea. It would appear that lineages dispersed to new terrestrial habitats in the west, notably uplifted by the central range orogeny, until eventually reaching the Bird’s Head during the Mio-Pliocene (7–5 Mya). Conversely, a past barrier appears to have prevented north–south dispersal. These data suggest that new habitat availability has primarily driven the diversification of Hylophorbus.
more » « less- NSF-PAR ID:
- 10478608
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Zoological Journal of the Linnean Society
- ISSN:
- 0024-4082
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract The genus
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