Haemogregarines of freshwater turtles from Southeast Asia with a description ofHaemogregarina sacaliaesp. n. and a redescription ofHaemogregarina pellegriniLaveran and Pettit, 1910

Abstract

SUMMARYThe uniform morphology of the developmental stages ofHaemogregarinaspecies and the insufficient information supplied by the simplistic descriptions of previous authors complicates their differential diagnosis and proper species identification. In this study, we detectedHaemogregarinaspp. in 6 out of 22 (27·2%) examined turtles originating from Southeast Asia,Malayemys subtrijuga(n= 4),Sacalia quadriocellata(n= 1) andPlatysternon megacephalum(n= 1), and compared them with the available literature data. Microscopic analysis of our isolates distinguished 2 morphological species,Haemogregarina pellegriniand one new species, being described in this paper asHaemogregarina sacaliaesp. n. Phylogenetic analyses based on 1210 bp long fragment of 18S rDNA sequences placed both haemogregarines firmly within the monophyleticHaemogregarinaclade. Isolates ofH. pellegrinifrom 2 distantly related turtle hosts,M. subtrijugaandP. megacephalum, were genetically identical. Despite the fact that numerousHaemogregarinaspecies of turtles have been described, the incompleteness of the morphological data and relatively low host specificity provides the space for large synonymy within this taxon. Therefore, a complex approach combining microscopic analyses together with molecular-genetic methods should represent the basic standard for all taxonomic studies.