Some like it cold: the glossiphoniid parasites of the Sicilian endemic pond turtle Emys trinacris (Testudines, Emydidae), an example of 'parasite inertia'?. (19th January 2016)

• Record Type: Journal Article
• Authors: Marrone, Federico; Sacco, Francesco; Kehlmaier, Christian; Arizza, Vincenzo; Arculeo, Marco
• Is Part Of: Journal of zoological systematics and evolutionary research. Volume 54:Number 1(2016:Feb.)
• Page Start: 60
• Page End: 66
• Publication Date: 2016-01-19
• Subjects: Hirudinea -- Placobdella costata -- Helobdella stagnalis -- host–parasite coevolution; Animals -- Classification -- Periodicals; Zoology -- Periodicals; Evolution -- Periodicals; 578.012
• DOI: 10.1111/jzs.12117
• Languages: English
• ISSNs: 0947-5745

Abstract

Abstract: The freshwater turtles of the genus Emys and some leech species of the family Glossiphoniidae are the only Palaearctic representatives of primarily Nearctic taxa, which jointly colonized Eurasia and the Maghreb during the Miocene. The strict trophic relationships occurring between the glossiphoniid parasite leech Placobdella costata and its host, the emydid Emys orbicularis, make them a prime example of host–parasite cophylogenetic evolution. In the light of the discovery of the Sicilian cryptic endemic species Emys trinacris, which is the sister species to the widespread Palaearctic E. orbicularis, the possible cophylogenetic divergence of the turtle hosts and their leech parasites was investigated. In spite of the deep divergence scored between the two pond turtle species and of their allopatric distribution, their leech parasites proved to be conspecific and indistinguishable based on the implemented molecular marker. This unexpected decoupling might likely be ascribed to the different dispersal abilities of the two taxa and/or to the recent, human‐mediated introduction of the leech parasites in Sicily. If this last scenario is confirmed, the long‐term effects of the introduced leech parasite on the endemic Sicilian pond turtle Emys trinacris should be carefully monitored. In the frame of this study, representatives of the widely spread predatory leech Helobdella stagnalis were observed on E. trinacris . Molecular analyses of their stomach content allowed to rule out the possibility of the existence of a trophic relationships between these two taxa, in contrast to what was previously suspected, and suggest that H. stagnalis specimens were rather attached to the turtles for non‐nutritional reasons. Abstract : The possible co‐evolution of Emys spp. and their glossiphoniid parasites was investigated. In spite of the deep genetic divergence scored between the host species, their leech parasites proved to be strictly conspecific. This evolutionary decoupling is to be ascribed to the different dispersal abilities of the two taxa or to a recent translocation of Placobdella costata . Furthermore, Placobdella costata was proved to actually feed on Emys spp., while the existence of a trophic relationship between Helobdella stagnalis and Emys spp. was ruled out.