Aim Granite outcrops may be able to act as refugia for species during adverse climate change, owing to their topographic complexity. We assessed this hypothesis by examining phylogeographical patterns in a common, geographically widespread granite endemic, Stypandra glauca (Hemerocallidaceae). Location Granite outcrops of the Southwest Australian Floristic Region, Western Australia. Methods Twenty‐four tetraploid individuals of the granite endemic Stypandra glauca were sampled from each of 12 granite outcrops: 7 from a mesic environment and 5 from the semi‐arid region. Phylogenetic reconstruction and divergence‐dating was achieved using Bayesian and parsimony analyses of chloroplast haplotypes from 90 individuals. Nuclear diversity and population differentiation were analysed across all individuals using 10 microsatellite loci. Results Stypandra glauca exhibited high (chloroplast) or moderate (nuclear) levels of divergence among, and low diversity within, outcrops. Haplotype diversity was high in both sampling regions, and each haplotype was unique to one outcrop. There was little correlation between geographical and genetic distance. Both nuclear and chloroplast diversity were higher in southern (mesic) outcrops than in northern (semi‐arid) outcrops, although the level of chloroplast divergence among outcrops was similar for both climatic regions. Main conclusions The levels of divergence and low diversity revealed in S. glauca support a scenario of prolonged isolation and persistence on granite outcrops in both mesic and semi‐arid climatic regions, with no evidence of contraction–expansion dynamics across the outcrop network. The higher levels of diversity in the southern populations may result from the maintenance of a larger effective population size in southern regions, which retained more mesic climates during drier glacial periods. Although the climatic conditions differ between outcrops in this study, our results indicate that outcrops in both regions have harboured S. glauca throughout climatic changes, accentuating the value of these habitats to biodiversity conservation under future changing climate.

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Background: Numerous Cape Floristic Region (CFR) clades are found in the Afromontane region of Africa, causing speculation on the source of their distribution. The southern Escarpment has been postulated as a key link in the movement of Cape species between the CFR and these Afromontane areas. Aims: The strengths of three purported connections (the north-west, Matjiesfontein and south-east) between the CFR and the southern Escarpment are considered, and of the southern Escarpment track itself. Methods: A comprehensive database was compiled from which floristic comparisons and multivariate analyses were undertaken. Palaeo-connectivity was assessed from phylogenetic relationships determined from 19 phylogenies. Results: There is evidence of both palaeo-and current connectivity between the Escarpment and the CFR, most strongly for the SE connection. Current connectivity along the southern Escarpment track is relatively well supported between the eastern Nuweveldberge and Main Drakensberg but not between the Hantam-Roggeveld and Nuweveldberge. Palaeo-connectivity along the southern Escarpment track is well supported by the phylogenies. Conclusions: Climate regime may be a more important factor in floristic connectivity than geomorphological continuity. Historical connectivity along the southern Escarpment track suggests cyclical connectivity, probably in response to glacial-interglacial cycles and associated shifts in rainfall regimes along the southern Escarpment.

The Triglochin bulbosa complex (Juncaginaceae) from the Mediterranean region and Africa is revised. One new species, Triglochin buchenaui Köcke, Mering & Kadereit, and two new subspecies, Triglochin bulbosa subsp. calcicola Mering, Köcke & Kadereit and Triglochin bulbosa subsp. quarcicola Mering, Köcke & Kadereit, are described from South Africa. The only two Mediterranean taxa in the complex (Triglochin barrelieri, T. laxiflora) are elevated to species rank. Altogether seven species and four subspecies are recognised: Triglochin barrelieri, T. buchenaui, T. bulbosa subsp. bulbosa, T. bulbosa subsp. calcicola, T. bulbosa subsp. quarcicola, T. bulbosa subsp. tenuifolia, T. compacta, T. elongata, T. laxiflora and T. milnei. An identification key, detailed descriptions and accounts of the ecology and distribution of the taxa are provided. An IUCN conservation status is proposed for each taxon.

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