Zoogeographical and stratigraphical distribution of the genusZonocypris: Supportive evidence for Anatolian Diagonal and description of a new species from Turkey

Abstract

Since its first description from Madagaskar, there are about 16 living (Recent) species of the genus Zonocypris reported from Afrotropical, Neotropical and Palearctic regions. Similarly, there are about 16 fossils with two (sub)species of the genus known from the Early Cretaceous (e.g., India, France, Russia, China, Brazil) to Holocene (e.g., Albania). Among the species, the only species known with fossil and recent forms is Zonocypris costata. In Turkey, Zonocypris membranae with two subspecies (Z. m. membranae, Z. m. quadricella) is the only fossil species known while live individuals of Z. costata were encountered from six cities (Adıyaman, Diyarbakır, Gaziantep, Mardin, Malatya and Hatay) located on the southeast Anatolia. Additionally, Zonocypris mardinensis n. sp. collected from Mardin is now proposed as a new species which shows clear differences in the soft body parts and carapace structure. Overall, living species reported herein seem to inhabit comparatively warm (15-30°C) within the ranges of slightly acidic to alkaline (pH 6.81-8.44) and low to well oxygenated waters (3.05-18.8mg/l) where they can tolerate salinity (electrical conductivity 103-1910µS/cm) values within a limited elevational range (336-991 m). Our results suggest that geographic distribution of the recent living species of the genus is limited within southern parts of Turkey while fossil forms seem to exhibit much wider distribution in northern parts. Anatolian Diagonal as physical barrier may be considered to play a critical role on separating fossil (east-north regions) and recent (southeast region) forms of the genus in Turkey. This is the first supportive evidence provided by the species of the genus Zonocypris that the diagonal could have played the main role on its distribution.