The majority of Haemogregarina species have been based on the morphology of their erythrocytic stages and supposed strict host specificity. The quantity of species with a limited number of overlapping diagnostic traits has led to a considerable mess in haemogregarine taxonomy and significant synonymy. We analysed host specificity, intra- and interspecific variability, evolutionary relationships, and the distribution of the type species of the genus Haemogregarina – H. stepanowi. The morphology of blood stages and 18S rDNA sequences of this haemogregarine from four western Palaearctic hard-shelled freshwater turtles (Emys orbicularis, Mauremys caspica, Mauremys leprosa and Mauremys rivulata) were compared with Haemogregarina balli. Additional sequences of 18S rDNA of Haemogregarina-like isolates collected from three species of African hinged terrapins (genus Pelusios) were used to enlarge the dataset for phylogenetic analyses. Thirteen sequences (1085 bp) of Haemogregarina representing all four western Palaearctic turtle species were identical, corresponding to H. stepanowi, which is closely related to the Nearctic species H. balli. In our analyses, Haemogregarina spp. constituted a monophyletic clade sister to the genus Hepatozoon. Haemogregarina stepanowi possesses a wide distribution range from the Maghreb, through Europe, Turkey and the Middle East to Iran. We consider that the genus Haemogregarina has a low host specificity crossing the family level of its vertebrate hosts and that its distribution is likely to be linked to the vector and definitive host – the leech.

Because of burgeoning demand in the Chinese market and extensive habitat loss more than half of the freshwater turtle and tortoise species in Asia are categorized as Endangered or Critically Endangered on the IUCN Red List. To investigate the distribution and status of the native freshwater turtle species of Taiwan a trapping programme was conducted during 2001–2007, yielding a total of 1,828 individuals of four native species at 103 sites. Mauremys sinensis was the most abundant and widely distributed species; it was collected from 70 sites and accounted for 78.6% of all turtles captures. Mauremys mutica comprised 17.8% at 46 sites. Pelodiscus sinensis were captured in low numbers at 19 sites. No Mauremys reevesii were collected on the main island of Taiwan but the species was found on Kinmen Island near mainland China. Capture success was low at most sites and overall sex ratios were significantly male-biased in all species, suggesting that the freshwater turtles have suffered from the negative effects of habitat disturbance and extensive exploitation. Effective conservation measures are urgently required to ensure the viability of the native freshwater turtle species of Taiwan.