Further new species and records from the coastal dry forests and woodlands of the Rovuma Centre of Endemism

Abstract

Background and aims – The coastal dry forests and woodlands of Cabo Delgado Province (Mozambique), part of the proposed Rovuma Centre of Endemism that is shared with coastal southern Tanzania, are known to support high numbers of endemic and highly range-restricted species. Here we investigate the taxonomic status of three taxa that were discovered and highlighted as potential novelties during botanical surveys of northeast Cabo Delgado in 2003–2012.Methods – This study was based on standard practices of herbarium taxonomy and morphological analyses. The conservation (extinction risk) assessments are based on application of the Categories and Criteria of the IUCN Red List. Key results – Three new species are described, all of which are currently thought to be endemic to Cabo Delgado Province and recorded from the area around the coastal town of Palma and/or inland along the lower Rovuma River Escarpment. Casearia celastroides I.Darbysh. & J.E.Burrows (Salicaceae), the smallest African member of its genus, is assessed as globally Endangered. Convolvulus goyderi J.R.I.Wood (Convolvulaceae), which, in contrast, has the largest flowers in its genus in tropical Africa, is known only from the type collection and is assessed as Data Deficient (DD) but could potentially be threatened. Vitex franceseana I.Darbysh. & Goyder (Lamiaceae) is also assessed as globally Endangered. Crossopetalum mossambicense I.Darbysh., a species previously thought to be endemic to Cabo Delgado, is reported for the first time in neighbouring southeast Tanzania. A review of new species discoveries from Mozambique since 2010 reveals that 26 species (one third of the newly published species) are derived from the forests and woodlands of the Rovuma Centre of Endemism, which is a critical area for plant conservation in Mozambique.