Case Study
Submitted By
| Name: | Nicolas Puillandre |
| Institution: | Museum National d'Histoire Naturelle |
| Country: | France |
| Email: | puillandre@mnhn.fr |
Title & Categories
| Case Study Title: | Using barcoding to assess alpha-taxonomy of the Turrinae, a poorly-known subfamily of marine molluscs. |
| Focus Theme: | Adding barcodes to a large survey of a taxonomic group, Biotic inventory of multiple taxa in a region or habitat, Systematic revision of an entire taxon, Systematic revision of an entire taxon, Resolving discrete taxonomic problems, Systematic revision of an entire taxon, Species conservation, Environmental monitering/quality indicators, Biotic inventory of multiple taxa in a region or habitat, Adding barcodes to a large survey of a taxonomic group, Experimental application of barcodes to a new taxonomic group |
| Geographic Region: | Africa, Unspecified, Europe, Pacific Ocean, Central America, Mediterranean Sea |
| Habitat Type: | Terrestrial cultivated land, Terrestrial grasslands, Terrestrial - Other, Marine - Other, Terrestrial tropical forest, Terrestrial montane, Terrestrial grasslands, Terrestrial desert, Terrestrial - Other, Coastal wetlands |
| Taxonomic Group: | c: PLANTS, f: VERTEBRATES, c: PLANTS, d: INVERTEBRATES, d: Mollusca, c: PLANTS |
| Project Duration: | 9/2006 to 10/2008 |
Scope
The Turrinae is a hyperdiverse group of marine molluscs belonging to the Conoidea. Hundreds of species are described based only on shell morphology. However, accumulation of specimens during recent cruises set up by the MNHN of Paris and the IRD have alerted the specialists on the difficulty of using solely shell morphology to delimit species. Indeed, the variability of shell morphology is very important and moreover often continuous. It is thus not easy to base species delimitations solely on these characters. Others characters have been recently used (anatomy, radular shape), but contradictions between these characters and shell characters are common. In such hyperdiverse groups, for which traditional characters are difficult to use, a DNA taxonomy approach, including the COI gene, is thus particularly adapted.
Purpose
The aim of this project is to study Turrinae diversity mainly in the West Pacific to assess species delimitations within this group. As morphological characters seems unlikely for this purpose, an integrative taxonomy approach will be used, including molecular, morphological, geographical and ecological data.
Background
Recently, molecular taxonomy have received increasing attention (Vogler 2006) as a mean to define species boundaries in poorly known groups, where traditional characters, such as morphology, are difficult to assess. In this study, the Barcode fragment of the COI gene is sequenced for every collected specimens, without making any a priori species or population hypothesis. Then, several methods of species delimitation are used (MOTUs, Blaxter 2005; MYC, Pons et al. 2006) to propose primary hypotheses of species delimitations. These hypotheses are then evaluated using other available data such as shell characters, geographical area or depth of collection.
Logistics
Specimens collected during MNHN/IRD cruises are systematically preserved for molecular studies since 2004. More than 1000 specimens of Turrinae were collected in Philippines, Solomon and Chesterfield Islands, Vanuatu and Norfolk ridges. Collecting event data concerning each specimen are compiled in a database. Almost 700 specimens are already sequenced for two genes: the Barcode fragment of the COI gene and a 900pb length fragment of the 28S gene.