Morphometric data from spores of ten myxosporean species were statistically analysed to explore myxosporean intraspecific variation in measurements when obtained from a sample from: (1) the same plasmodium, (2) different plasmodia from the same host and (3) different host individuals and localities. In some cases, significant differences in spore dimensions were found between samples from the same plasmodium, highlighting the difficulty of obtaining representative measurements of myxosporean spore. In addition, significant differences in spore dimensions were found when plasmodia from the same site of infection were compared, suggesting that measurements of spores should come from several different plasmodia of the sampling to increase the reliability of the morphology data. Moreover, significant differences in spore dimensions were observed for most spore dimensions when data were compared between localities. In all cases, there was clear overlap in ranges of dimensions even when means differed significantly. The present statistical analysis shows that intraspecific morphometric variation of myxosporean species commonly occurs, highlighting the importance of reporting ranges of measurements for a species, not just the mean dimensions, and taking into account all evidence when assigning or describing myxosporean species., Yanhua Zhai, Christopher M. Whipps, Zemao Gu, Qingxiang Guo, Zizhen Wu, Hongmei Wang, Yang Liu., and Obsahuje bibliografii
The present study analysed the taxonomic status and phylogenetic relationships of two species of xiphidiocercariae of the ʻmicrocotylaeʼ group, Cercaria pugnax La Valette St. George, 1855, from Viviparus viviparus (Linnaeus) in the Ukraine and Cercaria helvetica XII Dubois, 1928 from Bithynia tentaculata (Linnaeus) in Lithuania. Molecular phylogenetic analyses based on sequences of the ITS2 region and partial 28S gene of the nuclear rDNA revealed that both these xiphidiocercariae belong to the Lecithodendriidae Lühe, 1901 and represent larval stages of lecithodendriids parasitic in bats. Cercaria helvetica XII clustered with the typical representatives of the genus Lecithodendrium Looss, 1896, being very close, but not identical, to Lecithodendrium linstowi Dollfus, 1931. Sequences of C. pugnax matched exactly the sequences of adult Paralecithodendrium chilostomum (Mehlis, 1831). Morphological descriptions of the cercariae are included; these represent the first report of non-virgulate xiphidiocercariae belonging to the family Lecithodendriidae. Until now, the presence of glandular virgula organ in the region of the oral sucker was considered a robust synapomorphy for the Lecithodendriidae and several closely related families. Our results have shown that the relative importance of this character is in need of a re-assessment., Olena Kudlai, Virmantas Stunžėnas, Vasyl Tkach., and Obsahuje bibliografii