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Decreased ambient temperature and shorter reproductive seasons are the two main obstacles that ectotherms face at higher elevations. Studies have shown that some life history traits such as phenological windows of activity, duration, and fitness components vary as elevation increases. However, studies on the elevational gradient at the southern range limit of species are lacking. In this study, we aim at assessing some aspects of the life history of a spider species, the sprassid Micrommata ligurina (C.L. Koch, 1845), across an elevational gradient from 30 to 1030 m in Northeast Algeria. There was strong evidence of an elevational shift in the phenology of reproduction with a delay rate of 2.2 days per 100 m of elevation, and the three quantiles of the phenology (10, 50, and 90%) shifted with the same magnitude across elevation. In all sites from low to high elevation, the species showed a decrease in number of individuals. The mean number of eggs was 200 ± 35 eggs, and the mean number of hatching eggs was 110.9 ± 23.5 eggs. The clutch size at high elevation sites was higher than that of low-elevation sites, but in contrast, the hatching success was higher at lower elevation sites. Overall, the species exhibited clear elevational clines in life history traits and abundance, suggesting a high potential of plasticity. This work constitutes the first study carried out on spider species ecology in the region.

Age is a critical intrinsic factor that influences the probability of survival of organisms on Earth. In many animals, the lifestyles and habitat occupancy of males and females are so different that the effect of age could be sex-dependent. To reveal such patterns in wild animal populations, we here use a natural population of the Mediterranean demoiselle Calopteryx haemorrhoidalis Vander Linden (Calopterygidae: Zygoptera) in Northeast Algeria to analyze the influence of age and sex on survival probability using daily capture–mark–recapture. We used stepwise model selection on Cormack–Jolly–Seber models that explain recapture and survival probability, including age and sex as covariates. We marked a total of 214 adults throughout the study period (41 days). The sex ratio did not deviate from unity. Recapture probability depended on sex and time, with a slightly higher recapture probability in males (0.30 [95% CI: 0.27–0.35]) than females (0.26 [0.22–0.30]). The survival probability was slightly higher in females (0.89 [0.86–0.91]) than males (0.86 [0.82–0.88]). The best model for the survival probability included an additive effect of sex and age, indicating that the survival probability of both sexes declined with age. Interestingly, the lifespan of some individuals reached 119–130 days, which is surprisingly long compared to other temperate damselflies. [ABSTRACT FROM AUTHOR]

1. Temporal isolation by cohort splitting is a life‐history mechanism that has been reported in many temperate insects, including those inhabiting freshwater habitats. Although the cohorts seem to maintain separate temporal niches in a specific location, the temporal isolation may be disrupted across a geographic gradient due to constraints imposed by seasonality. 2. This prediction was tested on two temporally isolated populations of the obligatory univoltine Lestes virens (Odonata, Lestidae) in north‐east Algeria. Although the two cohorts emerge at the same time in spring, one cohort reproduces in summer, while the second cohort estivates in summer and reproduces in autumn. A survey assessing the phenology and abundance was conducted on eight ponds across an elevational gradient (5–1012 m asl) using capture–mark–recapture and adult density sampling. 3. In all sites from low to high elevation, the species showed cohort splitting. The phenology of reproduction of both cohorts showed a delay with elevation, but the cline was 2.2 days for the summer cohort and 0.7 days for the autumn cohort per 100 m of elevation. Moreover, the density of adults in the autumn cohort was higher than that of summer cohort across the entire elevational range, and the difference increased with elevation. 4. These findings regarding the differential elevational cline in the phenology show that the temporal isolation of the two cohorts becomes narrower at high elevation, suggesting potential inter‐cohort temporal overlap at higher elevations. 5. The claim that the two cohorts of L. virens are true temporally isolated species needs further investigation. Lestes virens is a damselfly that shows sympatric cohort split behaviour in North Africa, but it is still unknown whether the cohorts maintain temporal isolation across the elevational gradient.The phenology of the two cohorts (summer and autumn) shifted to later dates with elevation, but the temporal distance between them declines with potential overlap at around 1000 m.The abundance of the autumn cohort was higher than that of the summer cohort across the entire elevation gradient, and more so at higher elevations. [ABSTRACT FROM AUTHOR]

The reproductive behaviour of the Atlanto-Mediterranean Erythromma lindenii Selys has been studied before in Europe, but not in North Africa where the climate is warmer. We investigated the reproductive behaviour in a natural population in Northeast Algeria. We found that the species is non-territorial with quasi-exclusive underwater oviposition. The duration of underwater oviposition was positively correlated to the maximum water depth. We suggest that females predominantly lay eggs underwater to avoid water evaporation, which is common in North Africa. We discuss the differences in the reproductive behaviour between European populations and one in North Africa. [ABSTRACT FROM AUTHOR]

The article presents a research study which examines the movements of Calopteryx exul, an endangered endemic damselfly. The study was conducted through capture-mark-resightings of the insect for five days in Salah Salah in north-east Algeria. Results reveal a resighting rate of 21.18% for males and 24.67% for females.