Background: Essential oils, obtained from plants, are an alternative for controlling ectoparasites, particularly lice, mites and ticks, due to the problems posed by chemical insecticides, such as insect resistance, environmental impacts and concerns related to human and animal health. This study aims to investigate and compare the insecticidal activity of essential oils from Origanum floribundum and Eucalyptus citriodora against the louse Bovicola limbatus. Methods: The chemical composition of the two oils obtained by hydrodistillation was determined by gas chromatography coupled with mass spectrometry (GC-MS) and a flame ionisation detector (FID-MS). To determine insecticidal activity, the essential oils were tested at different concentrations (0.05–0.8 µL/mL), with mortality recorded after 15 min, 30 min, 1 h, 2 h and 4 h of exposure. Results: A corrected mortality rate of 100% was achieved for concentrations of oregano and eucalyptus essential oils of 0.8 µL/mL and 0.4 µL/mL, respectively. The LC₅₀ values were 0.11 and 0.10 µL/mL for oregano and eucalyptus, respectively, after 2 h of treatment. The LC₉₀ values observed are 0.31 and 0.24 µL/mL for oregano and eucalyptus, respectively. Conclusion: Both essential oils have similar and promising insecticidal potential and could be an alternative to chemical insecticides in a control strategy that is more respectful of human and animal health and the environment.

Fruit flies (Diptera: Tephritidae) are cosmopolitan, species-rich, and yet poorly studied in Algeria, particularly in the agro area of Djelfa. We sampled fruit flies in orchard containing three types of trees apricot, fig and grapes at each site, using the yellow traps. Results show that the orchard differed significantly in species richness, abundance, diversity and evenness. A total of 956 individuals distributed by nine species of Diptera, including four species of fruit flies are collected. The results revealed that most abundant species are Drosophila melanogaster at the apricot fruit site (RA%=28.32%), Zaprionus indianus at fig fruit site (RA%=34.74 %) and Tephritis praecox at the grapes fruit site with (RA%= 51.61 %). The orchard selected a greater number of species and individuals, and higher diversity indices H′=2.40 bits; 2.32 bits and 2.02 bits. Statistically, the result of stepwise multiple regressions revealed a very strong correlation between the number of fruit fly species and the temperatures with (r=93.1%) and (Sig .000**). Thus, fruit flies appear to have rather arrow with the host plant requirements and their phenology was correlated with environmental differences. Our study highlighted for; the first time; the presence of Trupanea amoena in Algeria. This important and substantial preliminary work on this new species in Algeria provides a solid basis for future research and extension of the study in particular for monitoring and control of this dreaded agricultural pest.

The Erotylidae family remains poorly documented in North Africa, with very limited published data available on its distribution and ecological preferences. This study provides the first confirmed record of Triplax melanocephala (Latreille, 1804) within Algerian cork oak (Quercus suber) forests, significantly expanding the known range of this species in the region. A total of 71 specimens were documented, collected primarily through soil-surface interception traps deployed across multiple sites. Among these, 25 individuals were captured between 2015 and 2016 in different sections of the surveyed oak groves. Field observations revealed that T. melanocephala exhibits a strong association with decaying cork oak wood, particularly in trees heavily colonized by mature tinder fungi (Fomes spp.). Further investigation through careful dissection of these fungal growths uncovered an additional 30 specimens, reinforcing the species' reliance on this microhabitat. The beetles were most frequently found in moist, shaded areas of decomposing wood, suggesting that microclimatic conditions may play a key role in their distribution. The study sites included Oued Agouf, where 2 specimens were collected in 2015 and 4 in 2016; Ain Fegoum, with 6 specimens in 2015 and 8 in 2016; and El Maktoua, where 4 specimens were recorded in 2015 and 6 in 2016. These findings indicate a consistent presence of T. melanocephala across multiple locations, though population densities varied between sites. This discovery not only fills a gap in the understanding of Erotylidae in North Africa but also highlights the ecological importance of old-growth cork oak forests and their associated fungal communities in supporting specialized beetle fauna.

Understanding how climate and host plant characteristics drive pest dynamics is essential for sustainable vineyard management. This study investigated the seasonal population dynamics of Frankliniella occidentalis and Jacobiasca lybica across four grapevine cultivars (Dabouki, Muscat, Red Globe, Victoria) in Boumerdès, northern Algeria, during the 2022 growing season. Both species showed distinct seasonal patterns, with F. occidentalis peaking in mid-summer and J. lybica reaching maximum abundance in late August. Jacobiasca lybica was strongly correlated with temperature, whereas F. occidentalis was negatively influenced by rainfall. The generalised linear models highlighted the significant effects of climatic variables on pest abundance. Among the grape cultivars, Dabouki exhibited higher infestation levels by J. lybica compared with the other cultivars, while no significant cultivar-related differences were observed for F. occidentalis. Redundancy analysis identified temperature as the main environmental factor shaping pest population dynamics. These results highlight the combined influence of climate and cultivar susceptibility on pest dynamics and support locally adapted integrated pest management in Mediterranean viticulture.

Wildfire is a dominant disturbance in Mediterranean cork oak (Quercus suber) ecosystems, yet its medium-term consequences for insect assemblages remain poorly documented in North Africa. We compared burnt and unburnt stands in four suberaies of north-eastern Algeria (Djebel El Goufi/Lemdjalba, El Maktoua, Oued Agouf and Ain Fegoune) during two consecutive post-fire years (2015 and 2016). Across 16 station-year units, 402 insect species were recorded. Unburnt stands harboured 364 species against 111 in burnt stands, and 291 species were exclusive to unburnt stands. Sorensen similarity between burnt and unburnt stands was consistently low (mean 18.4% in 2015 and 10.8% in 2016), whereas unburnt stands remained comparatively stable between years (mean 61.9%) and burnt stands did not (22.5%). Principal component analysis of Hellinger-transformed abundances separated burnt from unburnt units along PC1, and PERMANOVA confirmed a significant effect of fire history (R2 = 0.25, p = 0.0001; ANOSIM R = 0.72, p < 0.001) with no significant year or interaction effect. UpSet and chord diagrams showed that species overlap was concentrated within, rather than between, fire-history classes, with only one to two species shared by all eight stations. Two years after fire, assemblages had not begun to converge towards the unburnt reference, indicating slow entomofaunal resilience and supporting the retention of unburnt refuges in post-fire management.