Integrative taxonomy of the Clavus canalicularis species complex (Drilliidae, Conoidea, Gastropoda) with description of four new species

ABSTRACT

The conoidean family Drilliidae Olsson, 1964 is a species-rich lineage of marine gastropods, showing a high degree of diversification in comparison to other families of Conoidea. Despite intensive molecular phylogenetic studies during the last decade that have led to notable rearrangements of conoidean systematics, the genus- and species-level taxonomy of Drilliidae has not thus far been affected and remains entirely based on shell features. In the current study we revisit species delimitation in a morphological cluster of species from the Indo-Pacific referred to as the Clavus canalicularis complex, using an integrative taxonomy approach. The species in the complex possess robust thick-walled shells typically over 15 mm in height with sculpture of prominent rounded nodules located at the whorl’s shoulder, sometimes sharp and squamiform, or producing long spines. We find that in addition to five known species, the complex comprises four new species. These are described as Clavus brianmayi n. sp. (New Caledonia), Clavus davidgilmouri n. sp. (the Philippines), Clavus andreolbrichi n. sp. (Vanuatu and New Ireland) and Clavus kirkhammetti n. sp. (Madagascar). Clavus exasperatus (Reeve, 1843), which was previously considered widely distributed in Indo-Pacific, is shown to be confined to the western Indian Ocean.

KEYWORDS:

• Conoidea
• Drilliidae
• species complex
• cytochrome c oxidase subunit I

Acknowledgments

The material in this paper originates from several shore-based expeditions conducted by MNHN and Pro-Natura International (PNI) as part of the Our Planet Reviewed programme (SANTO 2006, ATIMO VATAE, INHACA 2011, KAVIENG 2014, KOUMAC 2.1; principal investigator P. Bouchet) Scientific partners included the University of Papua New Guinea (UPNG); National Fisheries College, Kavieng, Papua New Guinea; Institut d’Halieutique et Sciences Marines (IH.SM), Université de Tuléar, Madagascar; Universidade Eduardo Mondlane, Maputo; the Madagascar bureau of the Wildlife Conservation Society (WCS); and the Conservatoire d'espaces naturels (CEN) de Nouvelle-Calédonie. Funders and sponsors included the Total Foundation, Prince Albert II of Monaco Foundation, Stavros Niarchos Foundation, Richard Lounsbery Foundation, Vinci Entrepose Contracting, Fondation EDF, European Regional Development Fund (ERDF), French Ministry of Foreign Affairs, Fonds Pacifique, the Government of New Caledonia, the Province Nord of New Caledonia and the Agence française de la biodiversité (AFB). Additional fieldwork included PANGLAO 2004, a joint project of MNHN and University of San Carlos, Cebu City. All expeditions operated under the regulations then in force in the countries in question and satisfy the conditions set by the Nagoya Protocol for access to genetic resources. We are grateful to Igor Muratov (NMSA) for providing photos of the type of Clavus groschi; the photo of the type of Drillia sikesi was accessed from the unpublished archive of images of Richard Neil (Dick) Kilburn. The authors thank Virginie Héros, Barbara Buge, Philippe Maestrati and Julien Brisset (MNHN) for their help in curating the vouchers and for their edits on the text of the manuscript. Comments of two anonymous reviewers helped to improve the quality of the manuscript. This work was supported by the Service de Systématique Moléculaire (UMS 2700 CNRS MNHN).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Russian Science Foundation (RU) [grant number 19-74-10020].