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The Maghreb population of Emys orbicularis extends over a narrow strip of northern Morocco, Algeria, and Tunisia. Our understanding of the presence of this turtle in Algeria, in contrast to Morocco and Tunisia, is quite limited and frequently rests on a few small-scale studies or even reports from a century ago. The present study provides the first complete data on the distribution and level of threat of this species in Algeria. A field survey was carried out based on the data obtained from scattered local reports and available studies that suggested the presence of the species in Algerian wetlands. Data on climatic and habitat preferences, the geographic elevation of inhabited localities, and their conservation status were collected. A total of 45 wetlands were inhabited by E. orbicularis, of which 40 were part of a well-interconnected eastern metapopulation, joined by an extensive hydrographic network. In some places, the species has persisted for over 130 years in the same wetland complex. However, the five remaining populations living in central North Algeria are fragmented, highly isolated, and therefore more threatened. With a few exceptions, turtles inhabit lowlands below 100 m above sea level. Detected sub-populations inhabit mostly stagnant waters (60%), sometimes dams and lakes (24%), and sporadically also slow-moving water bodies (16%). Altogether, the Algerian distribution of E. orbicularis extends to a total area of 2900 km2, a 40 km wide strip with a length of 490 km west of the Tunisian border. Although restricted to this narrow strip, the persistence of numerous populations in Algeria, especially in Numidia, testifies to their relatively better conservation status. In order to ensure the sustainability of these efforts, follow-up and monitoring activities should be suggested, with special attention paid to highly isolated populations to maintain their long-term viability.

We collected 1,671 Dermacentor reticulatus ticks from 17 locations in the Czech Republic, Slovakia, and Hungary. We found 47.9% overall prevalence of Rickettsia species in ticks over all locations. Sequence analysis confirmed that all tested samples belonged to R. raoultii, the causative agent of tick-borne lymphadenopathy.

We measured and compared the reproductive traits of the Mediterranean stripe-necked turtles Mauremys leprosa living in highly degraded–polluted vs. intact natural habitats in Algeria. Data on reproduction were obtained by using X-ray examination of gravid females and examination of nests. The results were opposite to the negative trend confirmed in most freshwater turtles exposed to pollution and suggested the ability of this species to flourish instead in highly degraded–polluted habitats. An optimum development was recorded for several reproductive patterns of the studied freshwater turtle under conditions considered uninhabitable for other vertebrates. Females exhibited record body sizes among conspecifics, which allowed them to carry significantly larger clutches, exceeding by up to 3 eggs the previously largest reported clutch. The mean clutch size (8.79 ± 2.70 eggs) was also higher than findings from previous studies, except for in some other polluted habitats. Furthermore, large females even with large clutches carried large eggs. Egg measurements in the disturbed habitat revealed new records exceeding those previously noted; in egg length (by 3.0 mm), egg width (by 2.8 mm), egg mass (by 1.8 g), and clutch mass (by 18.6 g). In comparison, the usual reproductive performances were observed in the intact natural habitat; female body sizes were significantly smaller and carried fewer eggs of smaller size.

Using data for the body size and shell shape of Algerian Testudo graeca, we assessed how proximate causes shaped the observed variation in the morphology of adults. All of the studied populations displayed significant sexual size and shape dimorphisms. Relative to body length, females displayed larger, more voluminous and domed shells than males. We found clear evidence that variation in body size at maturity influenced sexual size dimorphism. Body size at maturity depends on the duration of growth from hatching up to the point of reaching sexual maturity. In the studied populations, sexual maturity, estimated by counting growth lines, was always reached earlier in males than in females (a time difference of 1.4–3.0 years). Similar to sexual size dimorphism, geographic variation in adult body sizes was also influenced by variations in the corresponding sizes at maturity. Remarkably, the population with the largest tortoises had the latest mean maturation time: 9.1 for males and 10.5 for females. Thus, the later completion of maturation was a determinant for a larger size in adulthood. The largest tortoises among the studied populations were measured at the Djelfa locality, where the recorded sizes of males and females reached 186 and 230 mm, respectively.