Parmelioid lichens (Parmeliaceae) in southernmost South America

Abstract

The parmelioid lichens is a speciose group in the Parmeliaceae family, and the biodiversity of this group is still far from completely understood in many regions of the world. One such region is southernmost South America, viz. the parts of Chile and Argentina south of 49 and 46° S, respectively, and the Falkland Islands. Based on examination of 366 herbarium samples and a study of relevant literature, 51 species of parmelioid lichens are here accepted for southernmost South America, whereas 12 species reported from the area during the last decades have been rejected. Xanthoparmelia austrosorediata and X. tehuelchorum are described as new to science here. In addition, six species are reported as new to southernmost South America, three of which are new to Chile, whereas an additional five species are new to the Chilean region of Magallanes. The apothecia of Flavoparmelia gerlachei and Xanthoparmelia subplittii are described for the first time here. Xanthoparmelia is the largest genus in the area with 21 species, two still undescribed, followed by Hypotrachyna with 11 and Parmelia with five. The lichenologically least explored part of the area is the Patagonian steppe and adjacent areas. Half of the total number of species, including all Xanthoparmelia species, is concentrated to these arid areas, and the majority of these are species which are endemic to South America. Hypotrachyna species are characteristic of the humid evergreen forest zone along the coast, and most of these species have wide pantropical or subcosmopolitan distribution ranges and few records from the present study area. The strongest focus of the present study is the National Park Torres del Paine in Magallanes, and a total of 35 parmelioid species are reported from this area here. Several of these have had their only known localities in southernmost South America destroyed by the 2011/2012 forest fire. Exploration history, frequency, distribution and evolutionary patterns are also discussed for single species or groups of species.

Himantormia lugubris, an Antarctic endemic on the edge of the lichen symbiosis

“…The connection between this morphology and the Antarctic environmental conditions is still an open question but could be related with the building of a stronger structure to cope with high wind speeds and their abrasive effect on fruticose thalli. In Himantormia deusta, a sister species from the Tierra del Fuego mountains (Thell et al 2007), the axis is not as strong and dominant in the thallus morphology as in H. lugubris (Elvebakk et al 2014). It has been reported that the fungal cell wall rigidity is due to a molecular complex formed by chitin and α-1,3-glucan (Kang et al 2018).…”

A revision of species of theParmelia saxatiliscomplex in the Iberian Peninsula with the description ofP. rojoi, a new potentially relict species

“…The group has its centre of diversity in temperate regions of the Northern Hemisphere but has a cosmopolitan distribution (Hale 1987). While its occurrence in Antarctica has been confirmed with molecular data (Øvstedal & Lewis Smith 2001;Crespo et al 2002), its presence in southern South America (Stenroos 1991;Elvebakk et al 2014) and New Zealand (Galloway & Elix 1983) is not well understood and requires additional studies. Several more or less cryptic species within the complex have been discovered recently in Europe and North America, including P. ernstiae, P. imbricaria, P. mayi, P. serrana and P. sulymae (Feuerer & Thell 2002;Molina et al 2004Molina et al , 2011bMolina et al , 2017.…”

Past, present, and future research in bipolar lichen‐forming fungi and their photobionts

“…Th e presence of the bipolar element in the lichen biota in South America has also been highlighted in several studies (e.g., Messuti et al, 2003 ;Bjerke and Elvebakk, 2004 ). Some relatively common northern hemisphere species in families Cladoniaceae ( Stenroos and Ahti, 1990 ;León et al, 2013 ), Physciaceae ( Elvebakk and Moberg, 2002 ), and Parmeliaceae ( Stenroos, 1991 ;Elvebakk et al, 2014 ) have been reported from southernmost South America. A regional study focused on the lichen mycobiota of Aysén (44-47 ° S, southern Chile) revealed that ca.…”