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Abdelkrim J., Aznar-cormano L., Fedosov A.E., Kantor Y.I., Lozouet P., Phuong M.A., Zaharias P. & Puillandre N. 2018. Exon-Capture-Based Phylogeny and Diversification of the Venomous Gastropods (Neogastropoda, Conoidea), in Vidal N.(Ed.), Molecular Biology and Evolution 35(10): 2355-2374. DOI:10.1093/molbev/msy144
Abstract [+] [-]Transcriptome-based exon capture methods provide an approach to recover several hundred markers from genomic DNA, allowing for robust phylogenetic estimation at deep timescales. We applied this method to a highly diverse group of venomous marine snails, Conoidea, for which published phylogenetic trees remain mostly unresolved for the deeper nodes. We targeted 850 protein coding genes (678,322 bp) in ca. 120 samples, spanning all (except one) known families of Conoidea and a broad selection of non-Conoidea neogastropods. The capture was successful for most samples, although capture efﬁciency decreased when DNA libraries were of insufﬁcient quality and/or quantity (dried samples or low starting DNA concentration) and when targeting the most divergent lineages. An average of 75.4% of proteins was recovered, and the resulting tree, reconstructed using both supermatrix (IQ-tree) and supertree (Astral-II, combined with the Weighted Statistical Binning method) approaches, are almost fully supported. A reconstructed fossil-calibrated tree dates the origin of Conoidea to the Lower Cretaceous. We provide descriptions for two new families. The phylogeny revealed in this study provides a robust framework to reinterpret changes in Conoidea anatomy through time. Finally, we used the phylogeny to test the impact of the venom gland and radular type on diversiﬁcation rates. Our analyses revealed that repeated losses of the venom gland had no effect on diversiﬁcation rates, while families with a breadth of radula types showed increases in diversiﬁcation rates, thus suggesting that trophic ecology may have an impact on the evolution of Conoidea.
Accessible surveys cited (23) [+] [-]
Cunha T.J., Lemer S., Bouchet P., Kano Y. & Giribet G. 2019. Putting keyhole limpets on the map: phylogeny and biogeography of the globally distributed marine family Fissurellidae (Vetigastropoda, Mollusca). Molecular Phylogenetics and Evolution 135: 249-269. DOI:10.1016/j.ympev.2019.02.008
Abstract [+] [-]Fissurellidae are marine gastropods with a worldwide distribution and a rich fossil record. We integrate molecular, geographical and fossil data to reconstruct the fissurellid phylogeny, estimate divergence times and investigate historical routes of oceanic dispersal. With five molecular markers for 143 terminals representing 27 genera, we resolve deep nodes and find that many genera (e.g., Emarginula, Diodora, Fissurella) are not monophyletic and need systematic revision. Several genera classified as Emarginulinae are recovered in Zeidorinae. Future work should prioritize emarginuline genera to improve understanding of ancestral traits and the early evolution of fissurellids. Tree calibration with the fossilized birth-death model indicates that crown fissurellids originated around 175 Ma, and generally resulted in younger ages for the earliest nodes than the node dating approach. Model-based biogeographic reconstruction, supported by fossils, infers an Indo-West Pacific origin, with a westward colonization of new oceans via the Tethys Seaway upon the breakup of Pangea. Western Atlantic clades then served as source for dispersal towards other parts of the globe. As the sister group to all other fissurellids, Rimula is ranked in its own subfamily, Rimulinae stat. nov. New synonyms: Hemitominae syn. nov. of Zeidorinae stat. nov.; Cranopsis syn. nov. of Puncturella; Variegemarginula syn. nov. of Montfortula.
Accessible surveys cited (13) [+] [-]
D'udekem d'acoz C., Schön I. & Robert H. 2018. The genus Charcotia Chevreux, 1906 in the Southern Ocean, with the description of a new species (Crustacea, Amphipoda, Lysianassoidea). Belgian Journal of Zoology 148(1): 31-82. DOI:10.26496/bjz.2018.18
Abstract [+] [-]It is demonstrated here that Charcotia Chevreux, 1906 (Amphipoda) has priority over Charcotia Vayssière, 1906 (Gastropoda), and that Waldeckia Chevreux, 1906 has to be treated as an invalid objective junior synonym of Charcotia Chevreux, 1906. An analysis of a part of the mitochondrial COI gene of Charcotia indicates that Charcotia obesa sensu lato, consists of two genetically distant clades that fulﬁl the criteria of genetic species. Each genetic clade corresponds to a different morphotype. The ﬁrst one has a low triangular protrusion on the dorsal border of urosomite 1, a strong tooth on epimeron 3, and the posterodistal corner of the basis of pereiopod 7 is regularly rounded. It agrees with the original description of Charcotia obesa Chevreux, 1906. The second one has a protrusion of urosomite 1 prolongated by a sharp and usually long denticle, a small tooth on epimeron 3, and the posterodistal corner of the basis of pereiopod 7 is bluntly angular. The second form is treated herein as a new species, Charcotia amundseni sp. nov., which is described in detail. While the bathymetric distribution of the two Antarctic Charcotia species overlaps (0–300 m for C. obesa and 7–1200 m for C. amundseni sp. nov.), C. obesa largely predominates at depths of less than 150 m, while Charcotia amundseni sp. nov. predominates at greater depths. Both species are widely distributed and presumably circum-Antarctic.
Accessible surveys cited (3) [+] [-]