Examinando por Autor "Rosling, Anna"

Mostrando 1 - 2 de 2

Considerations and consequences of allowing DNA sequence data as types of fungal taxa
(International Mycological Association, 2018-05-24) Zamora, Juan Carlos; Svensson, Måns; Kirschner, Roland; Olariaga, Ibai; Ryman, Svengunnar; Parra, Luis Alberto; Geml, József; Rosling, Anna; Millanes, Ana María; Prieto, Marìa; Ekman, Stefan
Nomenclatural type definitions are one of the most important concepts in biological nomenclature. Being physical objects that can be re-studied by other researchers, types permanently link taxonomy (an artificial agreement to classify biological diversity) with nomenclature (an artificial agreement to name biological diversity). Two proposals to amend the International Code of Nomenclature for algae, fungi, and plants (ICN), allowing DNA sequences alone (of any region and extent) to serve as types of taxon names for voucherless fungi (mainly putative taxa from environmental DNA sequences), have been submitted to be voted on at the 11th International Mycological Congress (Puerto Rico, July 2018). We consider various genetic processes affecting the distribution of alleles among taxa and find that alleles may not consistently and uniquely represent the species within which they are contained. Should the proposals be accepted, the meaning of nomenclatural types would change in a fundamental way from physical objects as sources of data to the data themselves. Such changes are conducive to irreproducible science, the potential typification on artefactual data, and massive creation of names with low information content, ultimately causing nomenclatural instability and unnecessary work for future researchers that would stall future explorations of fungal diversity. We conclude that the acceptance of DNA sequences alone as types of names of taxa, under the terms used in the current proposals, is unnecessary and would not solve the problem of naming putative taxa known only from DNA sequences in a scientifically defensible way. As an alternative, we highlight the use of formulas for naming putative taxa (candidate taxa) that do not require any modification of the ICN.
Tremella macrobasidiata and Tremella variae have abundant and widespread yeast stages in Lecanora lichens
(Applied Microbiology International, 2021-03) Tuovinen, Veera; Millanes, Ana María; Freire-Rallo, Sandra; Rosling, Anna; Wedin, Mats
Dimorphism is a widespread feature of tremellalean fungi in general, but a little-studied aspect of the biology of lichen-associated Tremella. We show that Tremella macrobasidiata and Tremella variae have an abundant and widespread yeast stage in their life cycles that occurs in Lecanora lichens. Their sexual filamentous stage is restricted to a specific lichen: T. macrobasidiata only forms basidiomata on Lecanora chlarotera hymenia and T. variae only on Lecanora varia thalli. However, the yeast stage of T. macrobasidiata is less specific and can occur in L. varia lichens, whilst all life stages of T. variae may be specific to L. varia. Contrary to the hyphal stages, the yeasts are distributed across the thalli and hymenia of Lecanora lichens, and not limited to specimens with basidiomata. Tremella macrobasidiata was present in all studied L. chlarotera, and in 59% of L. varia specimens. Only in 8% of the L. varia thalli could none of the two Tremella species be detected. Our results indicate that lichen-associated Tremella may be much more abundant and widespread than previously assumed leading to skewed estimations about their distribution ranges and lichen specificity, and raise new questions about their biology, ecology and function in the symbiosis.