Endemism and hidden diversity of Habrophlebia, Eaton, 1881 in Algeria’s Northeastern Mountains (Ephemeroptera, Leptophlebiidae)

Northeastern Algeria has recently emerged as a hotspot of freshwater biodiversity and a refugium for both mountainous cold stenothermic and Afrotropical relict species. Intensive surveys of mayflies uncovered striking cryptic diversity within the genus Habrophlebia Eaton, 1881 (Ephemeroptera, Leptophlebiidae). By integrating molecular and morphological evidence, we describe five new species (H. callensis sp. nov., H. ghora sp. nov., H. seybouse sp. nov., H. annaba sp. nov., and H. edough sp. nov.).

Our findings increase the number of recognised Habrophlebia species in the Maghreb from nine to fourteen, all of which are endemic to the region. The results further suggest that northeastern Algeria constitutes a major diversification centre for Habrophlebia within the Maghreb and, more broadly, across the Mediterranean basin. Furthermore, distributional patterns support an east – west divide within the Maghreb, most likely shaped by distinct Quaternary glacial refugia.

Finally, we provide an updated identification key to the nymphs of Habrophlebia species in the western Palaearctic.