Rediscovery and redescription of clinostomid trematodes from Pelecanus onocrotalus

This study reports the first rediscovery and redescription of Euclinostomum lauroi in more than 40 years, based on an adult specimen recovered from the oesophagus of a great white pelican (Pelecanus onocrotalus) in Lake Tana, Ethiopia. An integrative taxonomic approach combining detailed morphological examination and molecular analyses (ITS rDNA and COI mtDNA) was employed. Scanning electron microscopy revealed additional features, including the fine surface morphology of the cirrus and genital opening. The same host individual harboured 2 Clinostomum species, C. phalacrocoracis and C. tilapiae, for which updated morphological redescriptions are provided. The record of C. tilapiae represents a new geographical record for Ethiopia. These findings expand current knowledge of African clinostomid diversity and identify Lake Tana as an important hotspot of trematode biodiversity. The newly generated morphological and molecular data refine species boundaries within Euclinostomum and Clinostomum and support the use of integrative approaches to resolve persistent taxonomic uncertainties in clinostomid systematics.