An annotated checklist of the coastal forests of Kenya, East Africa

Abstract

The inadequacy of information impedes society’s competence to find out the cause or degree of a problem or even to avoid further losses in an ecosystem. It becomes even harder to identify all the biological resources at risk because there is no exhaustive inventory of either fauna or flora of a particular region. Coastal forests of Kenya are located in the southeast part of Kenya and are distributed mainly in four counties: Kwale, Kilifi, Lamu, and Tana River County. They are a stretch of fragmented forests ca. 30−120 km away from the Indian Ocean, and they have existed for millions of years. Diversity of both fauna and flora is very high in these relicts and the coastal forests of Eastern Africa, extending along the coast from Somalia through Kenya and Tanzania to Mozambique, are ranked among the priority biodiversity hotspot in the world. In spite of the high plant species richness and their importance towards supporting the livelihoods of the communities that live around them, floristic studies in these forests have remained poorly investigated. Hence, based on numerous field investigations, plant lists from published monograph/literature, and data from BRAHMS (Botanical Records and Herbarium Management System) database at East African herbarium (EA), we present a detailed checklist of vascular plants recorded in this region. Our results show that Kenyan coastal forests play an essential role in the flora of Kenya and the plant diversity of the coastal forests of East Africa. The checklist represents 176 families, 981 genera, 2489 species, 100 infraspecific taxa, 90 endemic plants species, 72 exotic species, and 120 species that are included in the current IUCN Red List of Threatened Species as species of major concern. We also discovered three new species to the world from these relicts. Thus, Kenyan coastal forests present a remarkable and significant center of plant diversity.

An annotated checklist of the vascular plants of Taita Hills, Eastern Arc Mountain

“… Solanaceae , Asteraceae , and Fabaceae have the highest number of exotic species. This concurs with the study done by Ngumbau et al (2020) on the coastal forests of Kenya. A large number of these exotic species have colonized natural habitats and have also been listed as invasive ( Spanhove and Lehouck 2008 ; Thijis et al 2013 ).…”

“…The most species-rich families are Fabaceae , Rubiaceae , Asteraceae , Orchidaceae , Apocynaceae , Malvaceae and Euphorbiaceae . These results concur with similar studies conducted in other tropical rainforests such as the Coastal forests of Kenya ( Ngumbau et al 2020 ) and the Nandi forests ( Melly et al 2020 ), as well as other forests in the Afromontane archipelago of East Africa such as the Aberdares forests ( Kipkoech et al 2020 ), Agama forest ( Addi et al 2016 ), Afromontane forests of Ethiopia ( Senbeta et al 2014 ), and the Jibat Afromontane forest ( Burju et al 2013 ). Euphorbiaceae , Orchidaceae , and Rubiaceae are the most important families in Taita Hills in terms of species richness, endemism, and conservation status as all of them have substantial numbers in all three categories.…”

“…An unprecedented rate of extinction may exceed that of species recovery ( Wheeler et al 2012 ) and therefore prompting a crucial need for floristic inventories ( Palmer et al 1995 ). In Kenya, an updated flora checklist of several key areas of biodiversity importance such as Mount Elgon ( Tweedie 1976 ), Shimba Hills ( Luke 2005 ), Kakamega ( Fischer et al 2010 ), Mount Kenya ( Zhou 2017 ), Cherengani Hills ( Mbuni et al 2019 ), Coastal forests of Kenya ( Ngumbau et al 2020 ), Aberdares Ranges Forest ( Kipkoech et al 2020 ), and South and North Nandi forests ( Girma et al 2015 ; Melly et al 2020 ) have been documented.…”

Three new species of Uvariodendron (Annonaceae) from coastal East Africa in Kenya and Tanzania

“…This species is known as "Uvariodendron sp. nov. 1 of CFS" in the annotated checklist of the coastal forests of Kenya (Ngumbau et al 2020).…”

Stingless bees (Hymenoptera: Apidae) in Holocene copal and Defaunation resin from Eastern Africa indicate Recent biodiversity change

“…Unfortunately, the East Africa forests have a long history of deforestation, from 1900 to 2000 has been deforested up to 93.0% of their surface (Aleman et al, 2017). Today, the coastal region of East Africa contains highly fragmented habitats that are of global importance and concern in relation to their biodiversity (categorized as the East African Coastal Forest biodiversity hotspot) (Ngumbau et al, 2020), with these natural areas isolated in patches and greatly susceptible to destruction and loss of species (Schipper and Burgess, 2003;Tabor et al, 2010). Indeed, according to Burgess and Muir (1994), the distinct coastal vichaka forests and bushland have a 3-5-month-long dry season and harbor a profusion of endemic plants and animals specialized to this unique environment.…”