Additions to and revisions of the endemic and near-endemic Acanthaceae of Ethiopia
From Firenze University Press Journal: Journal of Plant Taxonomy and Geography (Webbia)
Hanny Lidetu, Department of Plant Biology & Biodiversity Management, College of Natural and Computational Sciences, Addis Ababa University
Gabriella Hoban, Royal Botanic Gardens
Olivia Lockyear, Strawberry Hill, Fishers Lane, Cold Ash, Berkshire
Aaron Belcher, The Estate Office, Tregothnan, Tresillian
Vida J. Svahnström, Royal Botanic Gardens, Kew, Richmond
Iain Darbyshire, Royal Botanic Gardens, Kew, Richmond
The Acanthaceae are among the most species-rich and morphologically and ecologically variable lineages of flowering plants (Manzitto-Tripp et al.2022). The family is particularly noteworthy for its high rates of local endemism, with many species having highly restricted ranges. Species of Acanthaceae can also be locally abundant and comprise an important component of the local ground flora, hence they are often of high ecological significance. Given this combination of high diversity, restricted rang-es and ecological importance, the Acanthaceae can be considered a high priority for plant conservation focus in many parts of the world (Manzitto-Tripp et al. 2022).Ethiopia is very rich in endemic plant species (Ensermu and Sebsebe 2014; Sebsebe et al. 2021) and, indeed, Sosef et al.(2017) estimated Ethiopia to be the tropical African country with the second highest rate of plant endemism, with a rate of 19.9% of the total flora, bettered only by neighbouring Somalia (32%). In the account of the Acanthaceae for the Flora of Ethiopia and Eritrea (FEE), Ensermu (2006) documented 215 taxa in 41 genera, this being the sixth most species rich fam-ily within the Flora region (Ensermu and Sebsebe 2014). Of these, 17 species and three subspecies were recorded as endemic to Ethiopia, with a further 11 undescribed potential endemics also documented (Ensermu 2006). Many other taxa of Acanthaceae were recorded from Ethiopia and only one other country. Since the FEE account, one new species in each of the genera Acantho-pale C.B.Clarke (A. aethiogermanica Ensermu), Blepha-ris Juss. (B. gypsophila Vollesen & Thulin), Lepidagathis Willd. (L. pseudoaristata Ensermu) and RhinacanthusNees (R. mucronatus Ensermu), and four new species in Barleria L. (B. baluganii Ensermu, B. ferox Ensermu & I.Darbysh., B. gidoleensis Ensermu & I.Darbysh. and B. negelleensis Ensermu & I.Darbysh.) have been described (Ensermu 2009; Vollesen and Thulin 2015; Ensermu and Darbyshire 2018), although all but B. gypsophila were based on species included as unnamed taxa in FEE. All these new taxa were thought to be endemic to Ethio-pia at the time of publication, but L. pseudoaristata has since been recorded from northern Kenya (Darbyshire et al. 2010) and so can be considered near-endemic.This publication is part of an ongoing study by Addis Ababa University, the Royal Botanic Gardens, Kew and the Ethiopian Biodiversity Institute on the diversity and extinction risk of the endemic flora of Ethiopia. In this current work we investigate several taxa of Ethiopian Acanthaceae for which further taxonomic work was required to fully delimit the taxa. The first concerns the Isoglossa somalensis Lindau complex in the forests of central and southern Ethiopia; the second concerns the Barleria induta C.B.Clarke (or B. prionitis L .) complex and the third concerns the status of Hypoestes microphylla Hochst. ex Nees, these latter two from the drylands of northern Ethiopia and western Eritrea.With the findings of the current work, the endemic Acanthaceae of Ethiopia currently stand at 21 species and two further infraspecific taxa, whilst an additional 23 species and one infraspecific taxon are considered to be range-restricted near-endemics for which Ethiopia holds a majority or globally important portion of the population.
DOI: https://doi.org/10.36253/jopt-16074
Read Full Text: https://oaj.fupress.net/index.php/webbia/article/view/16074
