Raesaenenia

Raesaenenia
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Fungi
Division: Ascomycota
Class: Lecanoromycetes
Order: Lecanorales
Family: Parmeliaceae
Genus: Raesaenenia
D.Hawksw., Boluda & H.Lindgr. (2015)
Species:
R. huuskonenii
Binomial name
Raesaenenia huuskonenii
(Räsänen) D.Hawksw., C.Boluda & H.Lindgren (2015)
Synonyms
  • Phacopsis huuskonenii Räsänen (1948)
  • Protousnea huuskonenii (Räsänen) Divakar, A.Crespo & Lumbsch (2017)

Raesaenenia is a fungal genus in the large family Parmeliaceae. It is a monotypic genus, containing the single lichenicolous fungus Raesaenenia huuskonenii, which parasitises lichens of genus Bryoria in the Northern Hemisphere.

Taxonomy

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The genus was circumscribed in 2015 by David Leslie Hawksworth, Carlos Boluda, and Hanna Lindgren. The generic name honours Finnish lichenologist Veli Räsänen,[1] who described the type species as Phacopsis huuskonenii in 1948. The type specimen was collected by botanist Avi Johannes Huuskonen from Pielavesi (North Savo, Finland), where it was found on the thallus of the lichen now known as Bryoria implexa.[2]

In 2017, Divakar and colleagues used a then-recently developed "temporal phylogenetic" approach to identify temporal bands for specific taxonomic ranks in the family Parmeliaceae, suggesting that groups of species that diverged within the time window of 29.45–32.55 million years ago represent genera. They proposed to synonymize Raesaenenia with Protousnea, because Raesaenenia originated relatively recently and fell under the timeframe threshold for genus level.[3] This synonymy was not accepted by Robert Lücking in a later critical analysis of this technique for lichen systematics, who noted that "if taxonomy and classification are to reflect evolutionary history, then merging them into a single genus just because of the point in time they diverged is certainly not justified".[4]

Description

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Raesaenenia is characterized by having an ascus structurally similar to those of genus Phacopsis, but with somewhat cylindrical ascospores that have thickened caps of wall tissue at each end.[1] Raesaenenia huuskonenii grows on Bryoria species in the Northern Hemisphere.[5][6][1] Infection by the fungus results in blackened branches that are geniculately deformed (i.e., bent at a sharp angle).[7]

References

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  1. ^ a b c Divakar, Pradeep K.; Crespo, Ana; Wedin, Mats; Leavitt, Steven D.; Hawksworth, David L.; Myllys, Leena; et al. (2015). "Evolution of complex symbiotic relationships in a morphologically derived family of lichen‐forming fungi". New Phytologist. 208 (4): 1217–1226. doi:10.1111/nph.13553. hdl:10652/3753. PMID 26299211.
  2. ^ Räsänen, Veli (1948). Lichenotheca Fennica. Vol. 19–21.
  3. ^ Divakar, Pradeep K.; Crespo, Ana; Kraichak, Ekaphan; Leavitt, Steven D.; Singh, Garima; Schmitt, Imke; Lumbsch, H. Thorsten (2017). "Using a temporal phylogenetic method to harmonize family- and genus-level classification in the largest clade of lichen-forming fungi". Fungal Diversity. 84: 101–117. doi:10.1007/s13225-017-0379-z. S2CID 40674310.
  4. ^ Lücking, Robert (2019). "Stop the abuse of time! Strict temporal banding is not the future of rank-based classifications in Fungi (including lichens) and other organisms". Critical Reviews in Plant Sciences. 38 (3): 199–253. doi:10.1080/07352689.2019.1650517. S2CID 202859785.
  5. ^ Triebel, Dagmar; Rambold, Gerhard; Elix, John A. (1995). "A conspectus of the genus Phacopsis (Lecanorales)". The Bryologist. 98 (1): 71–83. doi:10.2307/3243643. JSTOR 3243643.
  6. ^ Peršoh, Derek; Rambold, Gerhard (2002). "Phacopsis — A lichenicolous genus of the family Parmeliaceae" (PDF). Mycological Progress. 1 (1): 43–55. doi:10.1007/s11557-006-0004-0. S2CID 9935563.
  7. ^ Hawksworth, D.L. (1978). "Notes on British lichenicolous fungi: II". Notes from the Royal Botanic Garden Edinburgh. 36: 181–198.
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