Diversity, occurrence, and conservation status of large branchiopods (Crustacea: Anostraca, Notostraca, Laevicaudata and Spinicaudata) in Northern Cape province, South Africa.

This article focuses on the diversity, distribution, and conservation status of large branchiopod crustaceans in the Northern Cape province of South Africa. Combining historical records (1950–2022) with recent field surveys and mesocosm hatching assays (2018–2023), the study identified 32 species, representing the highest species richness reported in southern Africa, including six endemic species and five recently described species from the province. Two species, Leptestheria calcarata and a potentially undescribed Phallocryptus species, were recorded for the first time in South Africa. Conservation assessments based on the International Union for the Conservation of Nature (IUCN) Red List indicate three species as critically endangered, 14 as least concern, and seven as data deficient, highlighting the need for updated evaluations given the last assessment was in the early 1990s. The findings underscore the Northern Cape as a significant biodiversity hotspot for large branchiopods and emphasize the importance of ongoing monitoring and conservation efforts in ephemeral aquatic habitats.