A unique diversity hotspot for Polycopidae (Ostracoda) in the Triassic of North Dobrogea

ABSTRACT

The present contribution explores the diversity of Early-Middle Triassic Polycopidae in North Dobrogea, Romania. Abundant and well-preserved specimens have been obtained from samples collected from the Deşli Caira section, adding unique scientific understanding of these often overlooked taxa in the fossil record. Their taxonomy is discussed, the first Triassic record of the genus Pontopolycope is reported and five new species are described (Polycope lazarusi Forel sp. nov., P. legio Forel sp. nov., P. ludwigi Forel sp. nov., Pontopolycope jeanlouisi Forel sp. nov., Pt. papai Forel sp. nov.). Issues regarding the orientation of species previously reported from the nearby Uzum Bair section are identified and the diagnosis of Polycope baudi, P. niculae and Pontopolycope densoreticulata are emended. For the first time, we describe the ontogenetic development of six species of Polycopidae and report on the occurrence of at least two species showing precocious sexual dimorphism. The high diversity of the Polycopidae assemblages from the North Dobrogea in the Early and Middle Triassic led us to consider this area as a biodiversity hotspot for these ostracod taxa.

KEYWORDS:

• Ostracods
• Polycopidae
• Triassic
• North Dobrogea Orogen
• diversity hotspot

Acknowledgments

Special thanks are extended to Prof. Dr. Larry Knox (Tennessee Technological University, USA) and Prof. Dr. Mark Warne (Deakin University, Australia) for providing important literature relevant to the Discoidella discussion. EG acknowledges the funding by the Romanian Academy through grants 84/1999 and 368/2001- 2002, and by the UEFISCDI (Ministry of National Education) through grant PNCDI-II-ID-1960/2009-2010, respectively. We are grateful to three anonymous reviewers for their comments that greatly improved this manuscript.

Disclosure statement

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