We present the results of a chromosomal study (C-, Ag-NOR-, endonuclease digestion, DAPI and CMA3 banding) carried out on four Tunisian species of amphibians: Bufo mauritanicus, B. viridis,Rana saharica and Discoglossus pictus auritus. For comparative purposes, our cytogenetic analysis was also extended to Moroccan specimens of B. mauritanicus and D. pictus scovazzi. Tunisian specimens of B. viridis display chromosome and chromatin characters very similar to those found in other specimens, both North African and Euro-Asian.

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.

Fasciolosis caused by Fasciola spp. (Platyhelminthes: Trematoda: Digenea) is considered the most important helminth infection of ruminants in tropical countries, causing considerable socioeconomic problems.

Rana saharica is the most widely distributed anuran in Tunisia. We examined morphological variation in 124 specimens as a function of their geographical origin, using univariate and multivariate statistics with traditional morphometrics. Our results supported the existence of three morphotypes of this species, correctly classified 84.7% of specimens, and indicated significant degrees of variation in morphometric characteristics between regions. No significant differences were found between sexes among populations.

The water frog Pelophylax saharicus is the most widespread anuran in North Africa and thus subjected to widely differing environmental conditions in different parts of its distribution range. In this paper we examined genetic structure of species 15 populations across Tunisia and eastern Algeria. We evaluated a potential role of mountain ranges as significant barriers to gene flow, using a partial sequences of the mitochondrial cytochrome oxidase I gene (COI).

Morphometric variation of Pelophylax saharicus was analysed using univariate and multivariate statistics, with both traditional and geometric morphometrics, based on 148 specimens from four different geographical localities in Tunisia and Algeria. The results show the existence of three morphotypes in Tunisia and one in Algeria, and indicate a significant degree of variation in morphometric characters between regions. Specimens from the southernmost region have the smallest body size and the greatest morphometric divergence from other populations.

To assess karyological and morphometric diversity within Discoglossus pictus Otth 1837, morphometric and cytogenetic analyses were carried out on five populations from the northern Tunisia and Algeria. A total of eight morphometric adult traits were evaluated, tadpole oral disc structure was described and chromosome patterns were assessed by means of conventional staining and banding methods (C-, Ag-NOR and CMA3 banding). Karyological data indicated the same chromosome and chromatin characters among the five populations.

The intraspecific variation of mitochondrial cytochrome b sequence was analysed for two widely distributed Tunisian anuran species, Discoglossus pictus and Pelophylax saharicus. We observed low genetic variation within both species (D. p. auritus 0.6% uncorrected genetic distances, P. saharicus0.2%) and the absence of genetic structure within both species in the studied region. There is no correspondence between previously described morphotypes of P. saharicus in Tunisia and our genetic data.

A new highly abundant satellite DNA from Discoglossus pictus (Dp-sat1) was isolated and characterized. The repetitive unit (0.51 kb) has 2 HindIII sites and only one SpeI site: digestion of genomic DNA with HindIII produces 3 fragments: HA (0.17 kb), HB (0.34 kb), and HC = HA + HB (0.51 kb), while digestion with SpeI produces the whole repetitive unit (0.51 kb) that contains both HindIII sites. Sequence analysis of cloned repeats indicates an average A + T content of 71%, with many A- and T-runs.

 Fasciolosis caused by Fasciola spp. (Platyhelminthes: Trematoda: Digenea) is considered the most important helminth infection of ruminants in tropical countries, causing considerable socioeconomic problems. Samples identifi ed morphologically as Fasciola sp. in Equus caballus host species from the city of Tunis (north of Tunisia) were genetically characterized, for the fi rst time, by sequences of the 1st (ITS-1), the 5.8S and 2nd (ITS-2) Internal Transcribed Spacers (ITS) of nuclear ribosomal DNA (rDNA). Comparison of the ITS of the Tunisian samples with sequences of Fasciola spp.