(Table 2) Collection sites and number of specimens of Usnea subgenus Neuropogon species

DOI

Usnea species of the Neuropogon group are amongst the most widespread and abundant macrolichens in Antarctic regions. Four principal species, U. antarctica, U. aurantiaco-atra, U. sphacelata and U. subantarctica, have been described on morphological grounds. However, identification to species level is often difficult and atypical morphologies frequently arise. Over 400 specimens were collected on the Antarctic Peninsula and Falkland Islands. Both morphological and molecular characters (ITS and RPB1) were used to compare samples to clarify taxonomic relationships. Morphological characteristics used included presence of apothecia, apothecial rays, soredia, papillae, fibrils, pigmentation and the diameter of the central axis as a proportion of branch diameter. Results revealed a very close relationship between U. antarctica and U. aurantiaco-atra, suggesting that they might constitute a species pair or be conspecific. Usnea sphacelata was comprised of at least two genetically distinct groups with no clear differences in morphology. One group included the first reported fertile specimen of this species. Usnea subantarctica was phylogenetically distinct from the other main Antarctic Usnea species, but clustered with U. trachycarpa. Genetic variation was evident within all species although there was no clear correlation between geographic origin and genetic relatedness. Phylogenetic analyses indicated that species circumscription in the Neuropogon group needs revision, with the principal species being non-monophyletic. None of the morphological characters, or groups of characters, used in this study proved to be completely unambiguous markers for a single species. However, axis thickness was supported as being informative for the identification of monophyletic lineages within the group.

Species identifications were based on morphological characters according to Walker (1985) and Øvstedal & Smith (2001).

Supplement to: Seymour, Fabian A; Crittenden, Peter D; Wirtz, Nora; Øvstedal, Dag O; Dyer, Paul S; Lumbsch, H Thorsten (2007): Phylogenetic and morphological analysis of Antarctic lichen-forming Usnea species in the group Neuropogon. Antarctic Science, 19(1), 71-82

Identifier
DOI https://doi.org/10.1594/PANGAEA.858324
Related Identifier https://doi.org/10.1017/S0954102007000107
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.858324
Provenance
Creator Seymour, Fabian A; Crittenden, Peter D; Wirtz, Nora; Øvstedal, Dag O; Dyer, Paul S (ORCID: 0000-0003-0237-026X); Lumbsch, H Thorsten
Publisher PANGAEA
Publication Year 2007
Funding Reference German Research Foundation https://doi.org/10.13039/501100001659 Crossref Funder ID 5472008 https://gepris.dfg.de/gepris/projekt/5472008 Priority Programme 1158 Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Resource Type Supplementary Dataset; Dataset
Format text/tab-separated-values
Size 72 data points
Discipline Earth System Research
Spatial Coverage (-78.870W, -71.867S, 18.010E, 78.900N); Potter Cove, King George Island, Antarctic Peninsula; Ecuador; Tierra del Fuego, South America; Antarctic Peninsula; Antarctica; Falkland Islands, East Falkland, East of Stanley; Svalbard
Temporal Coverage Begin 2001-11-01T00:00:00Z
Temporal Coverage End 2003-01-01T00:00:00Z