Arthrorhaphis
Creators: name: Frisch, Andreas
name: Ohmura, Yoshihito
name: Holien, Håkon
name: Bendiksby, Mika
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Fungi
Ascomycota
Lecanoromycetes
Umbilicariales
Arthrorhaphidaceae
Arthrorhaphis

description: Artificial key to the genus Arthrorhaphis.
— The morphologically poorly characterised “ Arthrorhaphis septentrionalis ” (Fig. 8F) and Arthrorhaphis sp. 1 are not included in the key. Characters for the parasitic species have been compiled from Obermayer (1994), Santesson & Tønsberg (1994), Kocourková & Van den Boom (2005), and Etayo (2017).
1. Lichenised thallus absent; species strictly lichenicolous .....2
1. Lichenised thallus present; lichenicolous stages present or absent.........................................................................7
2. On the thallus of foliose or squamulose lichens.............3
2. On the thallus of crustose lichens...................................6
3. Causing aeruginose discolouration of the host thallus; on squamules and podetia of Cladonia spp ....................... ................................................... A. aeruginosa (Fig. 6A)
3. Aeruginose discolouration of the host thallus absent; on other lichens...................................................................4
4. Asci predominantly 4-spored; hymenium 110–150 μm; on Phyllobaeis imbricata ......................... A. phyllobaeis
4. Asci predominantly 6- or 8-spored; hymenium ≥150 μm; on other lichens..............................................................5
5. Asci predominantly 6-spored; hymenium 200–250 μm; on Arctoparmelia incurva ... A. arctoparmeliae (Fig. 6B)
5. Asci 8-spored; hymenium 150–180 μm; on Melanohalea olivacea ........................................ A. olivaceae (Fig. 6C)
6. Hymenium (except epihymenium) ± clear; ascospores 3.5–4.5(–5) μm wide, 10–15-septate; on Dibaeis baeomyces ................................................ A. muddii (Fig. 6D)
6. Hymenium strongly inspersed; ascospores 2.5–3.5 (–4.5) μm wide, 7–9(13)-septate; on Baeomyces rufus .... ............................................................ A. grisea (Fig. 6E)
7. Ascospores of the alpina, jungens or vacillans type; Ca-oxalate crystals in the medulla usually present..............8
7. Ascospores of the citrinella type; Ca-oxalate crystals absent in the medulla or beneath the soredia (A. citrinella s.l.)................................................................................ 10
8. Ascospores (vacillans type); soredia absent..... A. vacillans
8. Ascospores of the alpina or jungens type; soredia present or absent.........................................................................9
9. Ascospores alpina type ..................................................... ........................... A. alpina var. alpina s.l. (Fig. 8A,C,E)
9. Ascospores jungens type .................................................. ............................ A. alpina var. jungens s.l. (Fig. 8B,D)
10. Soredia or granules absent; thallus distinctly bullate-areolate; parasitic stages absent...........................................11
10. Soredia or granules present (occasionally indistinct); thallus areolae present or absent; parasitic stages present or absent...........................................................................12
11. Thallus surface ± smooth and shiny; areolae folded in ridges and with central cavity or resting in umbrella-like fashion on black hyphal strands; Australasia ................... .............................................. A. catolechioides (Fig. 7A)
11. Thallus surface ± verrucose, matt to slightly shiny; areolae convex to distinctly bullate, not folded in ridges; pale yellow medulla present; East Asia ... A. bullata (Fig. 7F)
12. Thallus forming small compact colonies on saxicolous bryophytes and cyanobacteria; thallus surface entirely disintegrated into finely granular to farinose soredia; parasitic stages absent; East Asia and Scandinavia .......... .................................................... A. farinosa (Fig. 7D,E)
12. Thallus otherwise; parasitic stages present or absent........13
13. Thallus entirely of small loose to compact aggregations of granular soredia on saxicolous bryophytes; parasitic stages absent; Europe and Iceland .................................... ................................................... A. citrinella (Fig. 7B,C)
13. Thallus of discrete to confluent areolae on soil, terricolous bryophytes and plant remains, or parasitic on Baeomyces spp. (rarely on other terricolous lichens); areolae breaking into soredia, rarely completely disintegrated or esorediate; widespread in the Northern Hemisphere........ ........................................................ A. vulgaris (Fig. 6F)
description: Published as part of Frisch, Andreas, Ohmura, Yoshihito, Holien, Håkon & Bendiksby, Mika, 2022, A phylogenetic survey of the ascomycete genus Arthrorhaphis (Arthrorhaphidaceae, Lecanoromycetes) including new species in Arthrorhaphis citrinella sensu lato, pp. 936-962 in TAXON 71 (5) on pages 955-957, DOI: 10.1002/tax.12718, http://zenodo.org/record/14047464