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Friday, October 25th, 2024
| Time | Event | ||||||||
| 7:12a | [Herpetology • 2024] A multi-gene Phylogeny of the Asian Kukri Snakes (Oligodon Fitzinger, 1826): Sharpening the Blade of the second largest Serpent Radiation (Squamata: Colubridae)
Highlights • We present the most comprehensive phylogeny of Oligodon assembled to date. • Molecular phylogeny comprises nearly two-thirds of all currently recognized Oligodon species, with data from three mitochondrial and three nuclear genes. • We propose an updated intrageneric classification of Oligodon, recognizing eight phylogenetically defined species groups. • Oligodon likely originated in mainland Southeast Asia during the late Oligocene, with most species-level diversification starting in the Miocene. Abstract With 90 recognized species, kukri snakes in the genus Oligodon Fitzinger constitute the second largest snake radiation in the world. Oligodon species are collectively distributed across the Asian continent and possess several ecological and morphological attributes that are unique amongst other snakes. Despite their high levels of species richness, evolutionary relationships within Oligodon are poorly understood due to a limited number of samples and genetic markers available in earlier phylogenies. In this study, we assembled the largest molecular dataset of Oligodon to date, which we use to assess the systematics and biogeography of the entire genus. Based on a combination of maximum likelihood and Bayesian phylogenies using fragments of three mitochondrial genes (12 s, 16 s, CytB) and three nuclear genes (Rag1, C-mos, BDNF), we identify eight deeply divergent clades within Oligodon, of which only two correspond with species groupings that were recognized by previous morphological classifications. Four species delimitation methods employed on the mitochondrial portion of the dataset resulted in dramatically divergent estimations of molecular operational taxonomic units (mOTUs). When combined, all four methods support the existence of unrecognized species-level lineages, but also indicate that several other Oligodon species are poorly differentiated genetically and require additional integrative taxonomic research to properly resolve. Based on divergence dating, we demonstrate that Oligodon began to diversify during the early Neogene and hypothesize that the most recent common ancestor of the genus originated in mainland Southeast Asia. We conclude by recognizing eight phylogenetically defined species groups and identify sampling gaps that require further investigation once new data becomes available. This study contributes to a greater understanding of snake evolution on the Asian continent and acts as a baseline for future studies of this speciose genus.   Justin L. Lee, Platon V. Yushchenko, Chatmongkon Suwannapoom, Parinya Pawangkhanant, L. Lee Grismer, Tan Van Nguyen, V. Deepak, Surya Narayanan, Sandeep Das, Thy Neang, H.T. Lalremsanga, Jian-Huan Yang, Daniel Jablonski, Mustafa Erkaya, Gernot Vogel, Aaron M. Bauer and Nikolay A. Poyarkov. 2025. A multi-gene Phylogeny of the Asian Kukri Snakes (Oligodon Fitzinger, 1826): Sharpening the Blade of the second largest Serpent Radiation (Reptilia: Squamata: Colubridae). Molecular Phylogenetics and Evolution. In Press, 108215. DOI: doi.org/10.1016/j.ympev.2024.108215 | ||||||||
| 9:02a | [Botany • 2024] Chrysosplenium insularis (Saxifragaceae) • A New Species from the southern islands of South Korea
Abstract We describe a new species, Chrysosplenium insularis J.E.Jang, K.H.Lee & H.Y.Gil, belonging to the family Saxifragaceae, from the southern islands of the Republic of Korea. Chrysosplenium insularis is morphologically similar to C. japonicum (Maxim.) Makino but can be distinguished by fairly persistent bulbils, green to yellowish-green sepals, four stamens, and cylindrical papillose seeds. Chrysosplenium insularis is also distinguished from C. alternifolium L., which is distributed in Europe, northern Russia, and the Caucasus, by the absence of stolons and green bracts. Phylogenetic analyses, based on one nuclear ribosomal (ITS) and two chloroplast (rbcL, matK) regions, confirmed that the new species was monophyletic and that C. insularis and C. alternifolium formed a sister relationship with robust support. Herein, we provide a detailed morphological description of C. insularis with its corresponding geographical distribution and comparison table and figures of related species. Key words: Chrysosplenium, morphology, new species, phylogeny, taxonomy
Chrysosplenium insularis J.E.Jang, K.H.Lee & H.Y.Gil, sp. nov. Diagnosis: Chrysosplenium insularis differs from C. japonicum in having fairly persistent bulbils, green to yellowish-green sepals, four stamens, and cylindrical papillose seeds. Etymology: The specific epithet “insularis” refers to its distribution on islands. Vernacular name: Island golden saxifrage: Seom-gwaeng-i-nun (섬괭이눈). Ju Eun Jang, Beom Kyun Park, Kang-Hyup Lee, Hyuk-Jin Kim and Hee-Young Gil. 2024. Description and Phylogenetic Position of A New Species, Chrysosplenium insularis J.E.Jang, K.H.Lee & H.Y.Gil (Saxifragaceae), from the southern islands of South Korea. PhytoKeys. 248: 91-104. DOI: doi.org/10.3897/phytokeys.248.131291 | ||||||||
| 2:00p | [Botany • 2024] Schiedea waiahuluensis (Caryophyllaceae) • An enigmatic New Species from Kaua'i, Hawaiian Islands and the first species discovered by a drone collection system
Abstract During a survey by the National Tropical Botanical Garden drone team, an enigmatic Schiedea was observed in December 2021on steep, rocky cliff faces of the Waiahulu Valley in the Waimea Canyon of Kaua'i. Subsequently, another survey was conducted in March 2022 and, by use of a remotely controlled cutting device suspended below the drone, the first herbarium specimen was collected, as well as a seed collection of an undescribed cliff-dwelling species of Schiedea. Detailed study of the collections and plants grown at the University of California, Irvine greenhouse showed that it had enlarged, somewhat whitish sepals similar to those of cliff-dwelling S. attenuata (the sole species in sect. Leucocalyx), yet differed significantly from all other species in the genus. It also shares with S. attenuata a woody habit, hermaphroditic flowers, coloured nectar and styles 5 to 7 or 8. We describe it here as S. waiahuluensis given the only known localities are on the cliffs of this valley and place it in an enlarged sect. Leucocalyx. With the discovery of this new species, there are 36 species in this Hawaiian endemic genus. Key words: Caryophyllaceae, conservation, drone exploration, Hawaiian Islands, Kaua'i, Schiedea 
Schiedea waiahuluensis W.L.Wagner, Weller, B.Nyberg, & A.K.Sakai, sp. nov. Etymology: Specific epithet refers to the Waiahulu cliff region of Waimea Canyon, Kaua'i, the only known location where the new species is found. Warren L. Wagner, Stephen G. Weller, Ann K. Sakai, Ben Nyberg and Kenneth R. Wood. 2024. Schiedea waiahuluensis (Caryophyllaceae), An enigmatic New Species from Kaua'i, Hawaiian Islands and the first species discovered by a drone collection system. PhytoKeys. 247: 111-121. DOI: doi.org/10.3897/phytokeys.247.130241  |
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