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The lower part of Fahdene Formation outcropping in northeastern Tunisia is represented by pelagic sequences and characterized by an important siliciclastic fraction that includes radiolarian and organic-rich beds of Allam Member. Litho-biostratigraphic analysis based on planktic foraminifera and radiolaria shows that deposition of organic-rich beds of Allam Member is confined to the Microhedbergella rischi Zone through the lower part of Ticinella primula Zone. Age diagnostic radiolaria recovered from these beds has been identified to constrain a direct age of black shale deposition. The assemblages can be correlated with the radiolarian biochronozone U.A.10-11 indicating an Early Albian to early Middle Albian in age. Radiolarian assemblages composed of species characteristic of U.A.10 biochronozone ( A. montisserei, D. gracilis) are associated with radiolarian taxa belonging to Costata Zone (U.A.9 Pseudoeucyrtis hanni and Thanarla pseudodecora), which can be correlated with Dercourt Member in the Ionian Zone and Paquier level of the Vocontian Basin (southeast of France). Biostratigraphic and abundance curves analysis has demonstrated significant diversification of cryptocephalic Nassellaria and Archaeodictyomitrae, probably adapted to eutrophic conditions that characterized the Aptian-Albian transition. Ecological conditions may have governed the stratigraphic range of many cosmopolitan taxa (i.e., Pseudodictyomitrae lodogaensis) compared with stratigraphic distributions schemes reported from other domains. The timing of black shales deposition was diachronic due to local geodynamic conditions and upwelling currents distribution. The Allam black shales are correlative with the oceanic anoxic event OAE1b which is characterized by the widespread of supraregionnally organic-rich beds in the Mediterranean Tethys basins across the Aptian-Albian transition. [ABSTRACT FROM AUTHOR]

Leishmaniasis are a group of vector-born, parasitic diseases caused by protozoan of the Leishmania genus, that includes visceral or cutaneous forms. Cutaneous leishmaniasis (CL) refers to a group of diseases because of the variability of clinical manifestations, caused by a large number of Leishmania species. In Tunisia, three different forms of CL are encountered, having different causal agents L. infantum, L. major and L. tropica. For the purpose of this study, we assessed the potential of polymorphic sites in dipeptidyl peptidase III (DPP III) encoding gene to differentiate among Leishmania species encountered in Tunisia. A pair of forward and reverse primers amplifying a 664 bp DPP III sequence were designed in regions including 2 mutations in the forward primer and 1 in the reverse, and were used to amplify DNA from diverse species of Leishmania parasites including L. infantum, L. major, L. tropica, L. donovani, L. chagasi, L. arabica, L. aethiopica and L. tarentolae. Amplification was positive for all tested Leishmania species except for L. infantum, L. chagasi, L. archibaldi, L. donovani and L. tarentolae. In case of cutaneous Leishmania species encountered in Tunisia, amplification was positive for both L. tropica and L. major and negative in case of L. infantum. This ability to differentiate L. infantum from L. tropica/L. major constitutes a first step in the taxonomy of cutaneous species prevalent in Tunisia.