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In desert ecosystems, arthropods such as scorpions are understudied, and sufficient information is still lacking regarding their biodiversity. Specimen collection was carried out over 24 months (2016–2017). This study assessed the phenology, abundance, richness and diversity of scorpion species in arid ecosystems of the Sahara desert of Algeria (Ghardaïa). It examined the potential influence of climate parameters (precipitation, temperature and wind) on activity density, diversity and the phenological distribution of the species among seasons. We identified eight Buthidae species: Androctonus aeneas, Androctonus amoreuxi, Androctonus australis, Buthacus samiae, Buthacus spinatus, Buthacus elmenia, Buthus saharicus and Lissothus chaambi. Androctonus amoreuxi and Androctonus australis were the most abundant and omnipresent species, comprising 54.41% and 33.82% of all species found, respectively. Shannon’s index and the evenness index demonstrated a very poor diversity of scorpions in this region and a poor balance between the number of sampled species. Seasonal variation and climate parameters, i.e., temperature and wind, influenced the number, distribution, and the diversity of scorpions. The number of species found in Ghardaïa Province represent more than 20% of the scorpion species reported in Algeria.

In the Mediterranean, Urothemis edwardsii is one of the most threatened dragonfly species with a relict population restricted to the northeast of Algeria. Despite the recent subtle local expansion in the geographic distribution of the species during the past decade, studies on the life history of the species are still lacking. We carried out a study on the phenology of emergence and flight season on Lake Bleu, Northeast-Algeria. Using repeated sampling of exuviae and marking of adults during two seasons (2018 and 2019), we estimated the population size, sex ratio, and the temporal pattern of emergence and flight season. The first year (2018) was considerably drier than the second year (2019). We collected a total of 576 and 887 exuviae and 711 and 655 adults in 2018 and 2019, respectively. The sex ratio at emergence was slightly female-biased with 57.1% in the first year and equal to unity (50.5%) in the second year, respectively. The species started its emergence earlier in the dry year (2018). The emergence of the species was quite asynchronous where 50% of the population emerged after 11 days and 16 days in 2018 and 2019, respectively. The difference in population size (based on exuviae) and the temporal pattern of emergence and flight season were likely due to differences in weather between the two years. The current study provides useful information on the life history and plasticity of U. edwardsii, which could be used for the management of this locally Critically Endangered dragonfly.

Species adjust their behavior and life-history to adapt to local environmental conditions. Species with large ecological prevalence often show signatures of local adaptations to different environment, particularly in extreme ones. Here, we investigate local adaptation in different populations of the North African Sahara frog (Pelophylax saharicus) living in various environmental conditions that varies mostly in temperature, precipitation, and elevation by mean of common garden experiment aiming to estimate the growth rate under two predation treatments (absence or presence of non-lethal cues of dragon y larvae). First, we found an elevational cline in the reproductive phenology where, from low to high elevation, the reproductive season shifts to later dates, whereas that in arid environment was later than all other populations. We suggest that geographic differences in temperature and rainfall (in arid areas) explain this phenological pattern. Second, hatching success was overall high but showed a slight decline across elevation. Third, growth rate was generally faster in low and intermediate elevation populations, but slower in high elevation and arid environment populations. Populations in low and intermediate elevation responded to predation by reducing growth rate and the size at metamorphosis, but no predatory responses were recorded in high elevation and arid environment populations. Our study shows some life history signatures of local adaptation of P. saharicus in Northeast Algeria, which does not go in line with recent genetic analysis showing low population differentiation in the region.