Reassignment of Haemogregarina annularis from the Blood of Tarentola annularis to the Genus Hepatozoon Based on the Parasite Morphology and 18S rDNA Sequence Analysis

Purpose To date, two haemogregarines have been described from the white-spotted wall gecko, Tarentola annularis in Egypt. These species are Haemogregarina annularis and Haemogregarina tarentannulari. Although these two species initially were described as different species parasitizing T. annularis, both forms look identical due to their similar morphology and morphometric characteristics from the same host species. Here we will clarify, using traditional morphological description of the blood and tissue stages, combined with molecular analysis, the identity of the haemoparasites infecting T. annularis in Egypt. Methods Thin blood smears were screened from 50 gecko, Tarentola annularis and merognic stages were identified in the lung of the infected geckos. Parasite DNA was extracted and PCR was carried out to amplify parasite 18S rDNA. Results Morphological criteria of parasite stages, mature gamont stages and mergonic stages were similar to the two previously reported Haemogregarina species. In the phylogenetic tree, the present haemogregarine fell within a clade comprising most of Hepatozoon species infecting reptiles. Conclusion Our morphological comparison supported that the two previously described Haemogregarina species were the same and allowed us to consider Haemogregarina tarentannulari as a junior synonym of Haemogregarina annularis. Our phylogenetic analysis gave us the opportunity to reassign Haemogregarina annularis to the genus Hepatozoon and being identified as Hepatozoon annularis n. comb.