Description of Brachylecithum mackoi n. sp. (Digenea: Dicrocoeliidae) from the European hedgehog, Erinaceus europaeus (Insectivora: Erinaceidae).

A new hepatic dicrocoeliid species, Brachylecithum mackoi n. sp. (Digenea, Dicrocoeliidae), is described from the European hedgehog, Erinaceus europaeus (L.) (Insectivora, Erinaceidae). An infected host was found in the Mediterranean island of Elba (Italy), and more than 60 individuals were isolated from the biliary ducts. The holotype and 55 paratypes were examined. Brachylecithum mackoi n. sp. differs from congeneric species found in mammal hosts by having well-developed lappets in the ventral sucker, a sloping uterus between anterior testis and acetabulum, no overlap between vitellaria, and metrical features in the body size, sucker diameters, cirrus sac, and size of eggs. The only other Brachylecithum species of erinaceids in Europe and Africa, Brachylecithum aetechini Dollfus, 1951, differs from the new species in the above-mentioned morphological characters, greater dimensions of the body, and oral sucker, pharynx, cirrus sac, and egg dimensions. The presence of B. mackoi n. sp. in Elba Island is discussed in the light of apparent host specificity of erinaceid dicrocoeliids and geographical distribution of Palearctic and Ethiopian Erinaceidae.

Morphometric and genetic variability of Rodentolepis asymmetrica (Hymenolepididae) from the Pyrenean mountains.

Rodentolepis asymmetrica (Janicki, 1904), is a common hymenolepidid cestode recorded in several vole species (rodents) in the Palearctic. Here, we report a detailed analysis of this species, which includes metrical features and multilocus enzyme electrophoresis. Worms isolated from 4 species of arvicolid hosts in 3 localities in Spain and France from 1994 to 1997 were studied. All the worms used in the morphological study ranged between I and 5 individuals per host. Furthermore, all individuals were analyzed electrophoretically. Statistical analysis of metrical features in scolex, sexual segments, and eggs was carried out, and significant differences were detected only in sexual structures of mature segments. These differences were found in worms from each host species in different localities and in the same host species in 2 localities. Multivariate statistical analysis shows correct classification of worms in all cases. Surprisingly, we observed a lack of genetic variability at the 11 enzymatic loci analyzed, which could be explained by 2 nonexclusive hypotheses: (1) a preferential selfing mode of reproduction for these parasites, and (2) a weak effective size of parasite populations.