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

Abstract We combined historical records from the literature (1950–2022) with recent field surveys and mesocosm-hatching assays conducted in 2018–2023 and found a total of thirty-two species of large branchiopods in Northern Cape province of South Africa, the largest absolute species richness reported in any area in southern Africa. This highlights this province as an important hotspot for large branchiopods, with six endemic species. Five new species (two anostracans and three spinicaudatans) described in the past six years from southern Africa were from the province. Moreover, our study identified four new species awaiting formal description, which not only enrich the overall diversity but also contribute significantly to the conservation value and functional roles within ephemeral waterbodies. Two new South Africa and province records, namely Leptestheria calcarata (Wolf in Daday, 1923) and a potentially undescribed species of PhallocryptusBirabén, 1951 were recorded. Based on the IUCN conservation assessment, three species are classified as critically endangered (CR), 14 as least concern (LC), and seven as data deficient (DD). It is now an opportune time to update the assessment given that the previous assessment of large branchiopods in southern Africa was conducted in the early 90s. This large-scale, province-wide study, taken together with historical records aims to contribute to our understanding of large branchiopods in the Northern Cape province of South Africa.