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The decline of biodiversity, specifically of insects is one of the major topics in conservation biology. In several countries of Europe, recent studies have shown a severe decline in species number and biomass of insects. In most countries of much higher diversity, much less is known about the state of the insect fauna. In this study, we focus on the acridid grasshoppers of Iran as an indicator taxon for diversity decline in a high diversity region. We used data of two surveys to suggest a change in species number between 1963 and after 2000. In the surveys before 1963, the species diversity across multiple localities in Iran was much higher compared to more recent faunistic studies. While this data is not statistically analyzable as the sampling is not completely comparable, the trends show a clear pattern of decline, which likely reflects the reality, conforms well to individual observations of less frequent encounters in the field and matches global patterns of insect decline. However, more standardized quantitative surveys are needed to generate statistically analyzable data. Potential reasons for the observed decline are severe draughts as a result of global climate change, habitat pollution, and destruction for construction and mining and especially overgrazing. Management actions need to be urgently put into place to stop the negative trends. Future studies need to document and test if these are taxon-specific trends or universal patterns in the region.
 

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The Palni Hills, part of the Western Ghats Mountain range in southern India, constitute a biodiversity hotspot, and their high elevation creates unique ecological conditions. Despite global recognition of the region as a biodiversity hotspot, many taxonomic groups remain poorly studied, including mayflies. We conducted a survey of mayflies in the Palni Hills to document the current diversity profile and analyse their altitudinal distribution patterns, ranging from 346 to 1685 m asl. Our sampling from April to October 2023 covered eleven sites, resulting in the collection of 788 individuals, representing 24 species, 16 genera, and six families. Four species are reported for the first time from Palni Hills. Notably, the families Baetidae, Heptageniidae, and Leptophlebiidae were the most species-rich, although individual population densities remained low. We have provided the updated taxonomic hierarchy, current diversity profile, and abundance of mayflies of Palni Hills. We have also highlighted the knowledge gaps in the taxonomy and distribution of Ephemeroptera within this study area