title: Identifying gastropod spawn from DNA barcodes: possible but not yet practicable.
abstract: Identifying life stages of species with complex life histories is problematic as species are often only known and/or described from a single stage. DNA barcoding has been touted as an important tool for linking life-history stages of the same species. To test the current efficacy of DNA barcodes for identifying unknown mollusk life stages, 24 marine gastropod egg capsules were collected off the Philippines in deep water and sequenced for partial fragments of the COI, 16S and 12S mitochondrial genes. Two egg capsules of known shallow-water Mediterranean species were used to calibrate the method. These sequences were compared to those available in GenBank and the Barcode of Life Database (BOLD). Using COI sequences alone, only a single Mediterranean egg capsule was identified to species, and a single Philippine egg capsule was identified tentatively to genus; all other COI sequences recovered matches between 76% and 90% with sequences from BOLD and GenBank. Similarity-based identification using all three markers confirmed the Mediterranean specimens' identifications. A phylogenetic approach was also implemented to confirm similarity-based identifications and provide a higher-taxonomic identification when species-level identifications were not possible. Comparison of available GenBank sequences to the diversity curve of a well-sampled coral reef habitat in New Caledonia highlights the poor taxonomic coverage achieved at present in existing genetic databases, emphasizing the need to develop DNA barcoding projects for megadiverse and often taxonomically challenging groups such as mollusks, to fully realize its potential as an identification and discovery tool.
authors.affiliation: UMR 7138, Systématique, adaptation, évolution (UPMC/IRD/MNHN/CNRS), Université Pierre et Marie Curie (UPMC), CP26, 57 rue Cuvier, 75231 Paris cedex 05, France Department of Invertebrate Zoology, Smithsonian Institution, National Museum of Natural History, MRC 163, PO Box 37012, Washington, DC 20013-7012, USA Muséum National d'Histoire Naturelle, 57 rue Cuvier, 75231 Paris cedex 05, France GENOSCOPE, Centre National de Séquençage, 91000 Evry, France.
authors.forename: N
authors.initials: N
authors.lastname: Puillandre
authors.forename: E E
authors.initials: EE
authors.lastname: Strong
authors.forename: P
authors.initials: P
authors.lastname: Bouchet
authors.forename: M-C
authors.initials: MC
authors.lastname: Boisselier
authors.forename: A
authors.initials: A
authors.lastname: Couloux
authors.forename: S
authors.initials: S
authors.lastname: Samadi