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Ecological and biogeographical characteristics of 14 species of Tenebrionids (Coleoptera Heteromera) so far known for the Djerba Island (Tunisia, Gulf of Gabes) are illustrated for the first time. Basing on distribution we may recognize South-Western Mediterranean species; 3 centro-southern Mediterranean; 1 extended to the shores of Mediterranean Basin; 1 Western-Mediterranean element; 2 limited to South Mediterranean coast east of Morocco; 1 extended from Morocco (Atlantic coast) to Iran and Northern Arabic Peninsula, 1 extended from Algeria to Iran; 1 endemic of Djerba (Stenohelops berettai Marcuzzi), 1 widely distributed (Mediterranean s. lato). The distribution if often of relict type, due probably to its age. Basing on ecology there are 2 psammophilous species, 4 steppic, 3 rather euryoikous. Most Djeba Tenebrionids can be considered steppic (litoral or continental). Beside an endemic, 3 species show a distribution limited to centro-southern part of Mediterranean; the other are Western Mediterranean or widely distributed species (Scleron armatum and still more Tentyriagrossa and Zophosis punctata. The Tenebrionid coenosis –as well as insect coenoses as a whole– are heavily menaced by the continuously increasing anthropization, with human density, agriculture, grazing and tourism. The former determines a pumping of water from pits, with a possible salification of the water table, harmful to both invertebrates and plants. The excavation of clay for handicraft is another menace to environment, here included landscape. Grazing is bringing about a reduction and sometimes disappearance of coastal dunes, because of destruction of local vegetation (especially Gramineae). Measures of conservation characteristics of landscape invoked due to the great ecological and biogeographical interest of Tenebrionid coenoses living on Djerba since Miocene, and due to the systematic status of some species, still discussed, in this as in many steppic and desertic North African localities.

We studied the spring spatial distribution of the ciliate community coupled with environmental factors along the coast and in the open sea at 30 stations sampled (between 27 May and 9 June 2006) in the Gulf of Gabes (Tunisia, Eastern Mediterranean Sea). A total of 61 taxa belonging to 36 genera and 5 taxonomic classes were identified. The ciliate assemblage was numerically dominated by spirotrichs (86% of total ciliates). This group is largely dominated by the choreotrichs (92%) among which tintinnids represented 99%. The total ciliates abundance showed a gradual decrease from the coastal area to the open sea and an increase from the surface to the bottom. The maximum abundance (400 cells l-1) and biomass (6.29 µgC l-1) were found in station 27, close to Djerba Island. The tinitinnid Rhabdonella spiralis was cosmopolitan, being found almost at every station and at each depth, while other taxa may be exclusive to the neritic area, others to the open sea area. The distribution of species in the Gulf of Gabes seemed most likely influenced by the combined effects of hydrographic conditions, zooplankton predation and urban interferences.

Given the growing interest of consumers worldwide in safe, healthy and good quality olive oil, the present study aimed to investigate a number of Tunisian virgin olive oil varieties in an attempt to procure physico-chemical characteristics of interest to the local and global olive oil industry, particularly in terms of variety and area of cultivation. Eight samples collected from Chetoui, Chemlali, Zarrazi, and Zalmati Tunisian cultivars located at Sfax, Thibar, Zarzis, and Jerba were employed. Various physic-chemical parameters were investigated, including free acidity, peroxide value, UV absorption, pigment concentrations, oxidative stability, fatty acid composition, phenolic compounds and sterols. The findings revealed high heterogeneity within and between the varieties. The Chemlali Jerba" and Zarrazi oil samples showed high oleic acid and low linoleic acid concentrations, rich phenolic compounds, and high stability. The sterols fractions in Chemlali Sfax, Chemlali Jerba, and Zalmati olive oils displayed high levels of β-sitosterol, campesterol, and ∆-5-avenasterol. Overall, the olive oil from Chemlali Jerba presented higher levels of natural antioxidants and oxidative stability. Its chemical composition was also noted to be particularly interesting in terms of fatty acid contents, minor components, and antioxidants, namely sterols, tocopherols, carotenoids, and phenolic acids.

The mudsnail taxon Hydrobia s.l. plays a major role in numerous ecological and parasitological studies. Yet, its taxonomy is confusing and its biogeography is poorly understood. A principal problem is that taxa of Hydrobia s.l. belong to morphostatic radiations – widely allopatric species radiations with little or no habitat diversification and a low level of anatomical change. So far, three morphostatic radiations can be identified within Hydrobia s.l.: Hydrobia s.s., Peringia, and Ventrosia. These radiations are identical with the putative genera of Hydrobia s.l. The purpose of the paper is to infer phylogenetic relationships within one of these radiations, Hydrobia s.s. in the northern Atlantic and western Mediterranean. A total of 22 populations, including topotypical populations of five commonly used taxa, were studied genetically using partial sequences of the mitochondrial cytochrome c oxidase subunit I gene. Based on molecular data and the species concept we define, the following species and subspecies were identified: Hydrobia acuta acuta (Draparnaud, 1805) [=H. minoricensis (Paladilhe, 1875)], H. acuta neglecta Muus, 1963, and H. glyca (Servain, 1880) (=H. joossei van Aartsen, Menkhorst and Gittenberger, 1984). One population from Djerba, Tunisia (Hydrobia sp. A) and one population from Mallorca, Spain (Hydrobia sp. B) are genetically distinct from all other taxa studied here. Both populations potentially represent new species. Due to the fact that only one population each has been studied, and so the degree of variation within these two taxa cannot be assessed, a final decision regarding their species level cannot yet be made.

La myiase conjonctivale est une affection caractérisée par la présence accidentelle de larves de mouches au niveau de la conjonctive. Nous rapportons 11 cas de myiase conjonctivale afin d’attirer l’attention des ophtalmologistes sur cette rare pathologie, éclaircir son diagnostic, son traitement et ses complications. Les signes cliniques étaient ceux d’un corps étranger évoluant d’une façon bruyante. Le diagnostic a reposé sur la détection des larves à l’examen à la lampe à fente, larves qui ont été identifiées comme celles du premier stade d’Oestrus ovis. Le traitement consistant à l’extraction des larves une à une a été suivi du soulagement immédiat des malades. En conclusion, un traitement adéquat et précoce prévient l’évolution vers les complications sévères de l’ophtalmomyiase interne.

The composition of the essential oil obtained by hydrodistillation from the aerial parts of several populations of Artemisia campestris L. (Asteraceae), collected from four areas of south-eastern of Tunisia (Bengardane, Benikhdache, Jerba and Tataouine), was analysed by GC–MS. Thirteen to fifteen components were identified in each sample, representing more than 95% of the total oil. All samples were dominated by the presence of β-pinene (24.2–27.9%), p-cymene (17.4–22.3%) and α-pinene (4.1–11.0%), representing more than 45% of the total oil. The distribution of other components in the different extracts was qualitatively and quantitatively irregular. The variability of the composition can be attributed to the climatic and geographical conditions among areas