Redescription of Mactra bonariensis Philippi, 1893 and designation of a neotype

Abstract

Pérez, L.M. & Signorelli, J.H., iFirst article. Redescription of Mactra bonariensis Philippi, 1893 and designation of a neotype. Alcheringa, 1–10. ISSN 0311-5518.

During an ongoing revision of the Paraná Formation fauna of Argentina, the taxonomic status of Mactra bonariensis Philippi, 1893, was reassessed. The morphological characters of M. bonariensis provided in the original description and illustration do not allow clear delimitation of the species. The absence of type material of this species, coupled with difficulties in resampling the type locality due to urbanization, necessitates designation of a neotype. No records of this taxon were found in palaeontological and malacological collections. However, material collected from the Paraná Formation at ‘La Juanita’ (Entre Ríos, Argentina) comes from beds equivalent to those exposed at the locality from which Philippi described the original material. As this species may be confused with Quaternary and extant species from the region, a redescription is provided and a neotype designated.

Key words:

• Mactra
• taxonomy
• morphology
• Miocene
• Entre Ríos
• bivalves

Acknowledgements

Special thanks to the Drs. Miguel Griffin, Guido Pastorino and Miguel O. Manceñido, for the comments on an early version of the manuscript. We wish to thank Drs S. Nielsen and an anonymous reviewer, for their comments as reviewers for Alcheringa. We are also grateful to the staff of the ‘Museo de Ciencias Naturales y Antropológicas Prof. Antonio Serrano’ for help during the fieldwork. We thank the curators Kathie Way (NHMUK), Mónica Longobucco and Alejandro Tablado (MANC) for providing assistance on the type material analysis. LMP and JHS thank CONICET for doctoral fellowships. This contribution was partially supported by the project PICT 14419 to JHS.