Notes on Tricalysia elmar sp. nov. (Rubiaceae, Coffeeae), and cloud forest of the Cameroon Highlands

Abstract

Background and aims – This paper reports a further discovery in the context of a long-term botanical survey in the Cross River-Sanaga interval of west-central Africa, focussing on species discovery and conservation.Methods – Normal practices of herbarium taxonomy have been applied to study the material collected. The relevant collections are stored in the Herbarium of the Royal Botanic Gardens, Kew, London and at the Institute of Research in Agronomic Development – National Herbarium of Cameroon. Key results – Species new to science recently discovered from the cloud (submontane) forests of the Cameroon Highlands in Cameroon are reviewed. Most of these species are rare, highly localised, and threatened by habitat destruction. These discoveries increase the justification for improved conservation management of surviving habitat. Tricalysia elmar Cheek (Coffeeae-Rubiaceae) is described as an additional cloud forest species new to science. Its taxonomic position is discussed, and it is compared with similar species of the genus. Restricted so far to four locations, Mt Kupe, Bali Ngemba, Lebialem and Nta Ali, its conservation status is assessed as Endangered (EN B1+2ab(iii)) according to the 2012 criteria of IUCN.

A new cloud forest treeLychnodiscus bali(Sapindaceae), Critically Endangered from the Bali-Ngemba Forest reserve, N.W. Region, Cameroon

“…Most of these new species were first described as point or near-endemics, but several have, with more research, been found to be more widespread e.g. Tricalysia elmar Cheek (Rubiaceae, Cheek et al . 2020a) now known to extend from Mt Kupe and Bali-Ngemba to e.g.…”

“…Korupodendron songweanum Litt & Cheek (Vochysiaceae, Litt & Cheek 2002), Vepris montisbambutensis Onana (Onana et al 2015), Vepris mbamensis Onana (Onana et al 2019), Vepris zapfackii Cheek & Onana (Cheek & Onana 2021) and Carapa oreophila Kenfack (Meliaceae, Kenfack 2011).Most of these new species were first described as point or near-endemics, but several have, with more research, been found to be more widespread e.g. Tricalysia elmar Cheek (Rubiaceae,Cheek et al 2020a) now known to extend from Mt Kupe and Bali-Ngemba to e.g. the Rumpi Hills(Lachenaud pers.…”

The endemic plant species of Bali Ngemba Forest Reserve, Bamenda Highlands Cameroon, with a new Endangered cloud-forest tree speciesVepris onanae(Rutaceae)

“…aff. ferorum is now published as T. elmar Cheek and is known also from Mt Kupe, Ngovayang and the Rumpi Hills (Cheek et al 2020b;Lachenaud pers. comm.…”

“…Examination of Table 2 shows that the number of strict endemics on Bali Ngemba is now nine, a drop of three from the 12 cited in Harvey et al (2004). This change has partly resulted from further survey work in other locations which has extended the known ranges of the species concerned so that they are no longer strict endemics (Cheek et al 2020b). It has also resulted from taxonomic revisions (Lachenaud 2019) and floristic studies (Couvreur et al 2021) that have reduced to synonymy three of the previously supposed strict endemics.…”