Cladonia subturgida (Cladoniaceae, Lecanoromycetes), an overlooked, but common species in the Mediterranean region

Abstract

Cladonia subturgida is a Mediterranean species that has been overlooked. Apparently it was restricted to the Iberian Peninsula and Canary Islands. However, during the study of the genus Cladonia in the Mediterranean region, new populations from 44 localities were found in: south France, Sardinia, south Italian peninsula, Crete and continental Greece. Distribution models based on MaxEnt, GLM, GAM and MARS algorithms were used to estimate the potential distribution of C. subturgida. Sicily, Corsica and the north of Africa were regions with suitable climatic conditions for C. subturgida where it has not been reported yet. The climatic variables with greatest relative influence in the C. subturgida distribution were the Precipitation of Warmest Quarter and the Annual Precipitation. Additionally, the ITS rDNA region was used to study the genetic variation of this species across its distribution area. Eleven haplotypes were found, one of them widely distributed through its geographical range. AMOVA analyses indicated lack of geographical structure.

Notulae to the Italian flora of algae, bryophytes, fungi and lichens: 11

“…It can be distinguished from similar species by the absence of scyphi and the presence of large pycnidia on the squamules, which are fragile with a pale-green upper side and a grey-brownish lower side (Burgaz et al 2020). This species was previously reported for Italy only for Calabria and Sardegna (Pino-Bodas et al 2020;Burgaz et al 2020).…”

Myrmecia, Not Asterochloris, Is the Main Photobiont of Cladonia subturgida (Cladoniaceae, Lecanoromycetes)

“…The presence of free-living Myrmecia in the soils of regions with extreme climates, such as the Namib Desert [80] or high mountain ecosystems [57,81], has led to the hypothesis that this genus is well adapted to extreme arid conditions [57]. Although the conditions under which C. subturgida thrives are not so extreme, its climatic optimum is in areas with low rainfall and prolonged summer drought [47]. This suggests that the association with Myrmecia could be an adaptive advantage for C. subturgida.…”

“…Thus, the association between C. subturgida and Myrmecia seems to be unique within the Rangiformes subclade. It is noteworthy that none of the species commonly co-occurring with C. subturgida, such as C. cervicornis, C. firma, C. foliacea, C. humilis, and C. rangiformis [47], use Myrmecia as a photobiont. This observation effectively rules out the possibility of Myrmecia serving as a highly specialized photobiont for this Cladonia community.…”

“…A selection of specimens (n = 39) from Pino-Bodas et al [47,48] was made to study the photobionts associated with C. subturgida (Table 1). We selected specimens from a wide range of geographical regions to represent as complete a distribution of the species as possible.…”

“…The current research centers on examining photobiont diversity within Cladonia subturgida Samp., a prevalent species in the Mediterranean region that thrives across a range of environments, including open Quercus forests and Cistus shrubs with acidic soil, spanning from the Thermo-to Supra-Mediterranean belts [46]. Species distribution models suggest that Cladonia subturgida could have a wider distribution, including the Canary Islands [47]. Cladonia subturgida is characterized by a persistent and dominant primary thallus, which often lacks a secondary thallus, with a prevalence of asexual reproduction.…”