Arthrorhaphis vulgaris (Schaer.) Frisch, Y.Ohmura, Holien

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, TAXON 71 (5), pp. 936-962 : 954-957

Arthrorhaphis vulgaris (Schaer.) Frisch, Y.Ohmura, Holien

& Bendiksby, comb. & stat. nov. ≡ Lecidea flavovires-

cens var. vulgaris Schaer., Lich. Helv. Spic. : 162. 1833

– Lectotype (designated here [MBT 10005504]):

SWITZERLAND. [Bern], ad sylvarum oras, Schaerer,

Lich. Helvet. exs. no. 204 (G!; isolectotypes: GZU n.v.,

M n.v., UPS!).

MycoBank 842554

= Bacidia flavovirescens var. detrita Vain. in Acta Soc. Fauna

Fl. Fenn. 53(1): 223. 1922 – Lectotype (designated by

Obermayer in Nova Hedwigia 58: 302. 1994): FINLAN-

DIA. Tavastia borealis, Pihlajavesi, ad terram, 1871, Vai-

nio s.n. (TUR-V No. 20972!).

MycoBank 842755

See Fig. 6F for an image of the species.

Description. – Thallus lichenised, forming small irregular colonies on acidic soils, terricolous bryophytes or plant remains, or a juvenile parasite on Baeomyces spp. , up to 6 cm in diam., (greenish) yellow, areolate; areolae discrete to mostly confluent, irregularly rounded to elliptical to lobate, moderately to strongly convex to distinctly bullate, 0.2–1.7 mm, matt to slightly shiny, smooth to strongly verrucose, entire to cracked to ± disintegrated into fine to coarsely granular soredia of 0.03–0.15 mm; medulla up to 0.5 mm thick, yellow, often absent; Ca-oxalate crystals absent. Apothecia lateral to or in between the areolae or separate from the lichenised thallus, 0.3–1.5 mm, single or clustered to 2–15, adnate to shortly and broadly stipitate, black, matt, the thick margin first protruding, later level with the flat to distinctly convex, ± coarsely rugose disc. Epihymenium dirty to brownish olive green, HNO 3 green, 12–25 μm. Hymenium unpigmented to pale olivish green, densely inspersed, 80–130 μm. Subhymenium 40–75 μm, dirty to brownish olive green. Exciple 40– 80 μm wide, dark dirty to brownish olive green, darker towards the outer edge. Paraphyses sparsely branched and anastomosed, 1–1.5 μm wide. Asci 80–115 × 10–12 μm. Ascospores acicular, parallel in the asci, (34.0–)51.0–72.0(–89.0) × (2.0–)2.2– 3.2(–3.5) μm (n = 201; l: mean = 61.6, SD = 10.60; w: mean = 2.7, SD = 0.47), (5–)7–11(–16)-septate. Pycnidia absent.

Chemistry. – Rhizocarpic acid (major), epanorin (minor); ± stictic acid and ± norstictic acid (from the host).

Distribution and ecology. – Arthrorhaphis vulgaris appears to be the most common and widely distributed taxon in A. citrinella s.l. Specimens have been seen from across the Northern Hemisphere, including northern North America, Greenland, Iceland, Europe, and northern Siberia. The species has been found in temperate-montane to arctic-alpine regions and usually grows on bare acidic soils, among terricolous bryophytes, and over plant remains in open habitats with sparse or open vegetation such as pastures, rocky places, arctic-alpine heathlands and tundra, or road-banks. The elevation ranges from sea-level to 3000 m. Except for A. bullata and A. alpina s.l., it is the only lichenised species in the genus where juvenile parasitism on Baeomyces spp. (or other terricolous lichens) has been observed among the studied specimens.

Notes. – Contrary to Arthrorhaphis citrinella s.str., typical specimens of A. vulgaris have a thallus formed of compact areolae, even so the areolate thallus organisation may be obscured in strongly sorediate individuals. Such individuals may be difficult to place if poorly developed, but only few such specimens have been seen. The two species are virtually indistinguishable in characters of their ascomata, but our data indicate a small but noticeable difference in ascospore size for A. vulgaris , (34.0–)51.0–72.0(–89.0) × (2.0–)2.2–3.2 (–3.5) μm vs (45.0–)58.0–88.0(–102.0) × (2.0–)2.5–3.5(–4.0) μm in A. citrinella . The variation in ascospore size, however, is pronounced within both taxa. Arthrorhaphis citrinella , furthermore, seems to be restricted to steep to vertical rock faces, overgrowing saxicolous bryophytes, while A. vulgaris is a primarily terricolous species that, however, is frequently found on rock walls and outcrops in soil filled fissures and on ledges covered by a thin soil layer.

The few specimens of “ Arthrorhaphis septentrionalis ” seen for this study do not allow for a reliable separation of this taxon from A. vulgaris without molecular data, particularly when Ca-oxalate crystals cannot be demonstrated in the medulla. Fertile material of “ A. septentrionalis ” differs by the much shorter ascospores located in the apical portion of the asci, but the relevance of this character is not clear and needs evaluation on a larger set of specimens.

For a separation from Arthrorhaphis farinosa and A. bullata , see under those species.

Selected specimens examined (a total of 68 specimens seen). – AUSTRIA. Kärnten, Saualpe W von Wolfsberg, 46°54 ′ 10 ″ N, 14°39 ′ 50 ″ N, 7 Sep 2013, Hafellner 82296 ( GZU) . Salzburg, Schladminger Tauern, SSW-facing slopes of Preber , 47°12 ′ 15 ″ N, 13°53 ′ 00 ″ E, 17 Aug 2005, Obermayer 10945 ( GZU) . Vorarlberg, Silvretta-Gruppe , Kl. Lobspitze 46°54 ′ 45 ″ N, 10°05 ′ 30 ″ E, 26 Aug 2008, Hafellner 81282 ( GZU) . CANADA. Alberta, Jasper National Park, Bald Hills at NW end of Maligne Lake , 52°44 ′ N, 117°40 ′, 2 Aug 1995, Rosentreter 9435 ( GZU) . British Columbia, Wells Gray Provincial Park, Battle Mountain , 51°55 ′ 28 ″ N, 119°53 ′ 23 ″ W, 22 Jul 2008, Ahti & al. 68741 (H) . Newfoundland, Butterpot Provincial Park, Big Otter Pond , 47°23 ′ 56.40 ″ N, 53°02 ′ 34. 80 ″ W, 9 Sep 2007, Lendemer 10201 ( Lichens of Eastern North America Exsiccati 275; ASU, BG, GZU, H, M, S) . GERMANY. Bavaria, Allgäuer Alpen, Sigiswanger Horn , 7 Sep 2004, Dornes K _OA 0855 (M-0166793) . Hesse. Main-Kinzig-Kreis, Sinntal, Stoppelsberg , 500–550 m, 10 Apr 1990, Frisch 90/77 (hb. Frisch) . GREENLAND. Northeast Greenland National Park, Constable Bugt , 83°34 ′ N, 32°01 ′ W, 7 Aug 2007, Hansen s.n. (Lichenes Groenlandici Exsiccati 1031; S) . Kujalleq, Narsaq community, Tugtugtooq, Sildefjord , 1 Aug 2005, Alstrup s.n. (C) . ICELAND. Austurland, Stöðvarfjörður, Hvalsnes , Aug 1997, Nordin 4905 ( UPS) . FINLAND. Uusimaa, Kirkkonummi, Porkkala, Grid 27°E 665 35, 11 Oct 1991, Ahti 50869a & Scutari (H) . ITALY. Udine, Karnische Alpen, Mt Crostis N von Comeglians, 2240 m, 17 Aug 1994, Hafellner 78774 ( GZU) . KOSOVO. Bogićevica, west of Deçan, 20°06 ′ 16 ″ N, 42°34 ′ 28 ″ E, 21 Aug 2012, Mayrhofer 19361 & Zekaj ( GZU) . NORWAY. Buskerud, Hol , UTMED50: MN 610 204, 19 Jul 1996, TØnsberg 23922 (BG) . Telemark, Drangedal , Henneseid Ø, UTMWGS84: 32V NL 1249 4655, 23 Aug 2010, Klepsland JK 10-L248 (O) . Hordaland, Odda, Sveinsgjerd , UTMWGS84: 32V LM 64 54, 16 Jul 1993, Ihlen 233 (BG) . Møre og Romsdal, Tresfjord, Lindsetheiane W of Nonsfjellet, 62°27 ′ 44.40 ″ N, 07°07 ′ 07.38 ″ E, 3 Jul 2015, Frisch 15/ No 47 (TRH-L-652385) . Nord-Trøndelag, Grong, Mt Geitfjellet , UTMWGS84: 33W, UM 68 46, 26 Jul 1993, Ihlen 379 (BG-L-15726) . Troms, Storfjord, S of Lávkajárvi, c. 500 m N of Skurcojohka , UTMWGS84: DB 794-798 785-790, 8 Aug 2003, Lindblom 1243 (BG) . Finnmark, Porsanger, Luovosvarre , 10 km SE of Skoganvarre, 16 Aug 1967, Vitikainen 3295 (H) . RUSSIA. Murmansk, Podpakta Bay , 29 Jun 2010, Konoreva s.n. (H) . Komi, Vorkuta, Paga river , 66°22 ′ 00.12 ″ N, 62°52 ′ 00.12 ″ E, 26 Jun 2007, Hermansson 15589c ( UPS) . Krasnoyarsk, Taimyr Peninsula, c. 8 km W of urochishche Belyi Yar , 70°05 ′ N, 87°43 ′ E, 7 Aug 1999, L. Zanokha s.n. (M) . SLOVAKIA. In monte Beniška supra transitum Čertovica 27 Aug 1985, Farkas & V ĕ zda s.n. (BG) . SLOVENIA. Pohorje, Gipfelplateau des Črni vrh SW Ribnicˇa na Pohorju , 18 Jun 1991, Mayrhofer & al. 10047 ( GZU) . SWEDEN. Gästrikland, Torsåker parish, 3100 m SO om Torsåkers kyrka, 60°29 ′ 32.90 ″ N, 16° 30 ′ 53.00 ″ E, 23 May 2009, Hellström 9262 (S) . Jämtland, Kall parish, Bjelkes copper mines, 63°27 ′ 55.80 ″ N, 13°05 ′ 48.87 ″ E, 30 Aug 2014, Nordin 7674 ( UPS) . Lycksele Lappmark, Sorsele parish, Vuornavagge , 66°02 ′ N, 16°11 ′ E, 4 Jul 2003, Ihlen 1298 ( UPS) . SWITZERLAND. Bern, Berner Alps, Grimselpass , 46°33 ′ 35 ″ N, 08°19 ′ 40 ″ E, 24 Aug 2006, Hafellner 69409 ( GZU) . Graubünden, Urner Alps, Gotthard group, Oberalppass , 46°39 ′ 20 ″ N, 08°40 ′ 15 ″ E, 23 Aug 2006, Hafellner 75549 ( GZU) . Valaise, Bagnes , Pte du Parc, 583.990, 094.084, 14 Aug 2008, Vust 951 (G) . UNITED STATES OF AMERICA. Alaska, Kenai Peninsula Borough, along Lost Lake Trail, 60° 14 ′ 20 ″ N, 149°25 ′ 40 ″ W, 28 Aug 2010, Hafellner 79990 ( GZU) . Maine. Washington Co., Steuben, Dyer Neck , Eagle Hill , Humboldt Field Research Institute , 44°27 ′ 29 ″ N, 67°55 ′ 29 – 54 ″ W, 7 Jul 2008, Harris 54722 (NY) .

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 )

Figures

Fig. 6. A, Arthrorhaphis aeruginosa (TØnsberg 19019, BG, holotype); B, A. arctoparmeliae (Kocourková & Kocourek JK5484 dpl., C); C, A. olivaceae (Santesson 11677, BG, isotype); D, A. muddii (Woods s.n., E, holotype); E, A. grisea (Th.M. Fries s.n., UPS, holotype); F, A. vulgaris (Norrlin s.n., H). — Scale: A–C, 0.5 mm; D–F, 1 mm. Photos: A. Frisch.

Fig. 8. A, Arthrorhaphis alpina (Schaer., Lichenes Helvetici Exsiccati 532, G, lectotype); B, A. alpina var. jungens (Lichenotheca Graecensis 23, E, isotype); C, A. alpina (Ohmura 10119, TNS); D, A. alpina var. jungens (Kalb, Lichenes Neotropici 577, M); E, A. alpina (Brusse 4515, UPS); F, “A. septentrionalis” (Hansen 026, C). — Scale: A–F, 1 mm. Photos: A. Frisch.

Fig. 7. A, Arthrorhaphis catolechioides (Moberg & Owe-Larsson NZ2:5, UPS); B, A. citrinella (Odelvik 10598, S); C, A. citrinella (Frisch 15/No100, TRH); D, A. farinosa (Ohmura 9312, TNS); E, A. farinosa (Thor 33718, UPS); F, A. bullata (Ohmura 10730, TNS). — Scale: A, B, E & F, 1 mm; C, 0.5 mm; D, 5 mm. Photos: A. Frisch.