Four new Micarea species from the montane cloud forests of Taita Hills, Kenya

Abstract

The genus Micarea was studied for the first time in the Taita Hills, Kenya. Based on new collections and existing data, we reconstructed a phylogeny using ITS, mtSSU and Mcm7 regions, and generated a total of 27 new sequences. Data were analyzed using maximum likelihood and maximum parsimony methods. Based mainly on new collections, we discovered four undescribed well-supported lineages, characterized by molecular and phenotypic features. These lineages are described here as Micarea pumila, M. stellaris, M. taitensis and M. versicolor. Micarea pumila is characterized by a minutely granular thallus, small cream-white or pale brownish apothecia, small ascospores and the production of prasinic acid. Micarea stellaris has a warted-areolate thallus, cream-white apothecia usually darker at the centre, a hymenium of light grey or brownish pigment that dissolves in K, and intense crystalline granules that appear as a belt-like continuum across the lower hymenium when studied in polarized light. Micarea taitensis is characterized by a warted-areolate thallus and cream-white or yellowish apothecia that sometimes produce the Sedifolia-grey pigment. Micarea versicolor is characterized by a warted-areolate, sometimes partly granular thallus and apothecia varying from cream-white to light grey to blackish in colour. This considerable variation in the coloration of its apothecia is caused by an occasional mixture of the Sedifolia-grey pigment in the epihymenium and another purplish brown pigment in the hymenium. Micarea stellaris, M. taitensis and M. versicolor produce methoxymicareic acid. The main distinguishing characters are presented in a species synopsis. Three of the new species are nested in the M. prasina group, and the fourth one (M. taitensis) resolves as a basal taxon to the M. prasina group. The new species inhabit montane cloud forests, which have fragmented dramatically throughout the Eastern Arc Mountains in recent decades.

Peltigera (Lecanoromycetes) on Mt Kilimanjaro, East Africa

“…Even though only c . 10% of the extent of the original habitats is remaining (Mittermeier et al 2004), the Eastern Afromontane biodiversity hotspot still harbours a staggering amount of diversity and endemism (Burgess et al 2007; Harper et al 2010; Mittermeier et al 2011), including lichens and lichen-symbiotic organisms (Suija et al 2018; Kaasalainen et al 2021 a , b ; Kantelinen et al 2021).…”

Lichen speciation is sparked by a substrate requirement shift and reproduction mode differentiation

“…However, the majority of sequences have already been prepared for our previous studies (e.g. Launis et al 2019b; Kantelinen et al 2021a). Genomic DNA was extracted from 1–3 apothecia of specimens stored for a maximum of one year, using the DNeasy Blood & Tissue Kit (Qiagen, Maryland, USA) following the protocol described by Myllys et al (2011).…”

“…The microlichen genus Micarea is an excellent model for studying the effects of reproductive traits and environmental factors on speciation. The genus is widespread worldwide and has lately received much scientific interest, resulting in over 20 new species descriptions (Czarnota 2007; Czarnota & Guzow-Krzemińska 2010; Sérusiaux et al 2010; van den Boom et al 2017; Guzow-Krzemińska et al 2016 & 2019; Kantvilas & Coppins 2019; Launis & Myllys 2019; Launis et al 2019a, b; van den Boom et al 2020; Kantelinen et al 2021a). Micarea shows intricate variation in substrate requirements and reproduction modes (Coppins 2009).…”

Identification key to the lichen species of the parmelioid clade in Kenya

“…Since Parmeliaceae is largely found in the Southern Hemisphere with main distribution centres being in southern Africa, South America and Australia (Elix 1993), field collectors in these regions frequently meet representatives of this taxonomic group. In the case of Kenya, 178 of the c. 900 lichen species belong to the parmelioid clade (Krog & Swinscow 1987;Swinscow & Krog 1988;Hale 1990;Staiger & Kalb 1995;Alstrup & Aptroot 2005;Alstrup & Christensen 2006;Archer et al 2009;Alstrup et al 2010;Kirika et al 2012Kirika et al , 2016aKirika et al , b, c, 2017aKirika et al , b, 2019Lücking & Timdal 2016;Bjelland et al 2017;Kantelinen et al 2021;Kirika & Lumbsch 2021) .…”

“…In the case of Kenya, 178 of the c . 900 lichen species belong to the parmelioid clade (Krog & Swinscow 1987; Swinscow & Krog 1988; Hale 1990; Staiger & Kalb 1995; Alstrup & Aptroot 2005; Alstrup & Christensen 2006; Archer et al 2009; Alstrup et al 2010; Kirika et al 2012, 2016 a , b , c , 2017 a , b , 2019; Lücking & Timdal 2016; Bjelland et al 2017; Kantelinen et al 2021; Kirika & Lumbsch 2021) .…”