Habrosia (Caryophyllaceae) a monotypic genus endemic to Western Asia

Habrosia (Sagineae, Caryophyllaceae) is a genus that includes only H. spinuliflora, a species occurring in Iran, Iraq, Syria, Lebanon, and Turkey (Irano-Turanian floristic chorological element). Based on the available molecular data published in 2011, Habrosia appears to be nested in a Minuartia-clade, which includes taxa currently recognized under the genus Sabulina. Consequently, Habrosia should be treated as a genus to be included in Sabulina. However, the molecular tree published in 2011 considered only 9 Sabulina members whereas, according to the current concept, Sabulina is a genus comprising about 65 species. Unfortunately, the molecular phylogeny including a larger Sabulina sample published in 2014 did not include H. spinuliflora and the taxonomic position of Habrosia remains, therefore, uncertain. With the aim of verifying the correct position of Habrosia in the tribe Sagineae with respect to its relationship to Sabulina, a comprehensive molecular investigation based on ITS sequences, linked to detailed morphological data, is presented. The results obtained revealed that Habrosia is not part of Sabulina. A detailed description of H. spinuliflora, its ecological preference, and a distribution map are provided. Eventually, the name Arenaria spinulifolia (basionym of H. spinuliflora) is lectotypified on a specimen preserved at G (barcode G00212963).