Molecular identification of Probolocoryphe uca (Sarkisian, 1957; Digenea: Microphallidae) from Kuwait Bay using ITS1 and ITS2 sequences.

Probolocoryphe species occur primarily as intestinal parasites of birds and mammals. Infection of the crab Nanosesarma minutum with the metacercarial cyst stages of Probolocoryphe uca is common in Kuwait Bay. In this study, the snail Cerithidea cingulata was used to determine if it would serve as first intermediate host in the parasite's life cycle. To determine the snail-crab link in the life cycle of P. uca based on rDNA molecular data, ribosomal internal transcribed spacer (ITS) regions of the metacercarial cyst stage from the crab N. minutum and the sporocyst stage from the snail C. cingulata were sequenced and compared. Sequence alignment clearly demonstrated that the sporocysts and metacercariae belonged to P. uca. Comparisons were also made between the ITS sequences of P. uca and other digenean species available in GenBank. NCBI databases were used for sequence homology analysis using BLAST, ClustalW, and MUSCLE. The phylogenetic trees based on the homology analysis of the ITS (1 and 2) sequences constructed using PHYLIP and MEGA 4.0 confirmed the identification and positioned P. uca in the Microphallidae family.