Redescription of Mehdiella microstoma and description of Mehdiella petterae sp n., with a new definition of the genus Mehdiella Seurat, 1918 (Nematoda : Pharyngodonidae)

The generic diagnosis of Mehdiella Seurat, 1918 is emended based on study a nd redescription of Mehdiella microstoma (Drasche, 1884) from the caecum of Testudo graeca Linnaeus, 1758 collected in Settat, Morocco and on study an d description of a new species, Mehdiella petterae sp. n., from the large i ntestine of Testudo hermanni (Gmelin, 1789) collected in Catalonia, Spain. Scanning electron microscopy (SEM) studies revealed substantial differences in the structure of the mouth and the caudal end, and made possible to dif ferentiate the new species from the others. SEM studies showed the real and sound characteristics of the genus Mehdiella, namely number of anal papill ae 2 instead of 3, post-anal papillae pedunculate or sessile instead sessil e.