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Larval forms of the genus Anisakis were reported infecting several fish species from the North African coasts of central Mediterranean Sea. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis was used to investigate the occurrence of larval forms of different Anisakis species in teleost fishes and squid from North African coasts of the Mediterranean Sea and to establish the geographical and host range of these parasites in this area. A total of 282 Anisakis larvae were identified by PCR-RFLP from 13 teleost fish species and one cephalopod species captured at different sites off the Algerian, Tunisian and Libyan coasts. The type I larvae were found with a frequency of 93.62% and were identified as belonging to the following species: Anisakis simplex s.str., Anisakis pegreffii, A. simplex s.str/A. pegreffii hybrids and Anisakis typica. The type II larvae were found to belong to Anisakis physeteris, with the frequency of 6.38%. The record of A. simplex s.str/A. pegreffii hybrids, previously recorded from the Spanish and Portuguese Atlantic coasts and the Alboran Sea, extends their geographic distribution to the Tunisian coasts. The occurrence of A. simplex s.str. and hybrids away from their known area of distribution may predict the successful use of Anisakis larvae for tagging Scomber scombrus fish stocks for fisheries management purposes. Moreover, the results reported provide valuable information regarding the diversity of Anisakis species in the study area, indicating that several Anisakis sibling and morphospecies coexist in the North African coasts of the Mediterranean Sea.

A sample of 22 Echinococcus granulosus isolates collected from 12 sheep and ten humans from a focus of cystic echinococcosis in western Turkey was examined by DNA sequencing of four mitochondrial genes (cox1, atp6, nad1, rrnS). Results demonstrated the presence of two species of E. granulosus complex, E. granulosus sensu stricto and E. canadensis. Of E. granulosus sensu stricto, the G1 genotype (including three microvariants) was found in 17 isolates from humans and sheep, the G3 genotype and an intermediate form G1/G3 in one isolate each (both from sheep). Of E. canadensis, the pig strain G7 was found in three isolates from sheep and human. This is the first report of this strain in Turkey. Its presence has implications for local control programs due to its shorter maturation rate in dogs compared with E. granulosus sensu stricto. Goat and/or wild boar are likely reservoirs for G7 in the region. We provided further data on the pattern and frequency of nucleotide substitutions within the G1/G3 cluster. Based on our results and GenBank records, G2 (Tasmanian sheep strain) is not considered as a discrete genotypic unit, as its sequences at polymorphic sites conform to microvariants of both G1 and (more often) G3.

Anisakid nematodes belonging to the Anisakis simplex complex are highly prevalent in several fish species off the coast of Portugal and are an important zoonotic problem in the Iberian Peninsula. Two reproductively isolated sibling species of the Anisakis simplex complex were identified from Pleuronectiformes inhabiting the Portuguese coast using restriction fragment length polymorphism (RFLP). Recombinant genotypes corresponding to presumptive Anisakis simplex sensu stricto and Anisakis pegreffii hybrids were also detected by this technique, as well as the species Anisakis typica. Although 25 species of Pleuronectiformes were investigated, Anisakis spp. larvae were only found in seven: Arnoglossus imperialis, Arnoglossus laterna, Lepidorhombus boscii, Citharus linguatula, Platichthys flesus, Dicologlossa cuneata and Solea senegalensis. The occurrence of hybrids in relatively sedentary fishes such as the Pleuronectiformes suggests that the Portuguese coast may constitute an area of hybridization and, therefore, is of particular interest for the study of the process of hybridization and speciation for these anisakids.

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