Abrothallus welwitschii Tul. ex Mont. (1852: 113)

Suija, Ave, Ríos, Asunción De Los & Pérez-Ortega, Sergio, 2015, A molecular reappraisal of Abrothallus species growing on lichens of the order Peltigerales, Phytotaxa 195 (3), pp. 201-226 : 215-216

Abrothallus welwitschii Tul. ex Mont. (1852: 113)

Mycobank MB#228963; Fig. 9

Type:—[ PORTUGAL], ad rupes et arborum truncos in Serra de Cintra [ Serra de Sintra ] Sticta sylvatica [host]. Maio 1840 [F.M.J.] Welwitsch (lectotype PC0040796!, designated here). [Lectotype ex Tulasne 1852:113; sub Sticta sylvatica , sinister teste]

Ascomata on the thallus of Sticta sylvatica bursting through thallus cracks on the surface of the lichen thallus, flat, covered with thick greenish pruina, some young ascomata are surrounded by black (necrotic) rim. Epihymenial layer of dark brown granules, hymenium olivegreen, up to 120 μm high, K+ colour intensified. Hypothecium light brown, hypothecial cells rectangular, covered with brown pigment, 4–8 × 3–7 μm (n=10). Asci bitunicate, clavate, 55–77 × 12–16 μm (n=10), with eight ascospores. Ascospores 2-celled, brown, verruculose, asymmetric, constricted slightly at septum, 14–(15.7 ±0.8)–17 × 5.5–(6.4 ±0.6)–7.5 (upper cell)/4.5–(5.8 ±0.6)–6.5 (lower cell) μm (n=20), l/w (upper cell) ratio = 2.1–2.9. Interascal filaments unequally dichotomosly branched, ca. 2–3.5 μm wide, the tip not or only slightly widened. Anamorph not observed.

Notes:—The collection of Abrothallus welwitschii cited by Montagne (1851, 1856) and Tulasne (1852) was found in PC under the file of Sticta sylvatica . The type material includes two thalli of S. sylvatica infected with A. welwitschii , obviously collected from the same locality and glued on the same sheet ( Fig. 9a, b ). The name A. welwitschii was not indicated on the sheet, and therefore lectotypication was needed. We examined the left thallus ( Fig. 9b ) and selected this as a lectotype. Abrothallus welwitschii was first mentioned by Montagne (1851: 77–79), the name, however, should be considered as nomen nudum according to ICN (2012) Art. 13. The name was validated by Tulasne (1852, as “ welwitzschii ”) following the description by Montagne (1856) of the same specimen. Therefore, according to the same ICN Art. 13, A. welwitschii Tul. ex Mont. (1852) has the precedence over the occasionally used name, A. welwitschii Mont. (1856) . The correct spelling of the type locality is most likely Serra de Sintra , a subtropical spot in Portugal where Sticta is relatively abundant ( SPO, pers. comm.).

The asexual morph was not observed in the lectotype, however, in a few examined specimens, both morphs are present. Pycnidia semi-immersed, ca. 130–340 μm wide. Conidiogenous cells holoblastic, lining the cavity of pycnidia, 10.4–(15.8 ±3.3)–19.2 × 4.8–(5.8 ±0.7)–6.4 μm. Conidia simple, hyaline, obpyriform with truncated end, 9.6–(11.2 ±0.6)–12.8 × 5.6–(6.2 ±0.6)–7.2 μm.

Abrothallus welwitschii has been collected from Europe ( France, United Kingdom, Ireland, Spain: Canary Islands, Portugal: Azores, Madeira, continental Portugal), New Zealand, Africa ( Kenya), North-America ( USA: California ( McGee 2003), Oregon, Alaska) and South America ( Chile). Hosts belong to the genus Sticta ( S. fuliginosa , S. limbata , S. nylanderiana , S. sylvatica ).

Additional specimens examined: — UNITED KINGDOM. Leighton, Lich. Brit. Exc. 33, Wales: Rocks, New Cut, Meadfort, Torquay, Devonshire, Sticta fuliginosa b. abortiva Schaer., parasitic on S. fuliginosa ( BR-LICH 4118- 44, K(M)157298, K(M)157299, H); Scotland: western Scotland, Seil, south of Balvicar, Ballachuan Hazelwood, forest of Corylus avellana , elev. ca. 5–30 m (56º16’00’’N 5º36’50’’W), trunk of C. avellana , on the thallus of S. fuliginosa , 25 May 2003, D. Ertz 3346, det. D. Ertz & B. Coppins ( BR-LICH 8601-65); Scotland: Glen Lochay Killin, Lecidea parmeliarum (= Abrothallus p.) parasitic on Stictina (= Sticta ) fuliginosa , September 1863, M. C[rombie] ( BM 000500259 (ex Herb. J.M. Crombie)); IRELAND. Connemara: Galway (V.C. H16), SW of Clifden, Errislannen Manor, S. sylvatica on Fraxinus , 9 July 1968, R. Santesson 19733 ( UPS (F-156135)450260); Eire, Co., Cork, m. Youghal, river Blackwater, S. limbata (on trees), 4 July 1969, D.S. Chapman, det. D.L. Hawksworth as A. parmeliarum (K ex IMI-149076); Cork, Kenmore, on S. sylvatica , 1969, D.S. Chapman, det. D.L. Hawksworth as A. parmeliarum (pycnidial) (K, ex IMI-149077); Galway, on S. fuliginosa , 6 August 1966, G. Morgan-Jones, det. as A. parmeliarum (K, ex IMI-190754); SPAIN. Canary Islands: Tenerife, Bosque de la Esperanza, Las Laguentas, Cumbres de la Victoria, forest with Pinus canariensis , elev. 1675 m (28º24’34’’N 16º25’16’’W), on S. limbata growing on rocks, 20 July 2007, D. Ertz 10817 & P. Diederich ( BR-LICH 1049-79); Bosque de la Esperanza, elev. 1300 m (28º25’N 16º23’W), 13 August 2001, V. Calatayud & M.J. Sanz ( VAL _Lich 25371); S of Los Silos, ca. 1 km W of Erjos, Monte del Agua, laurisilva, elev. 1140 m (28º19’N 16º48’W), on S. fuliginosa on branch, 22 July 2007, D. Ertz 10831 & P. Diederich ( BR-LICH 1639-87); Las Montañas de Anaga, along main road from Las Mercedes to Chamorga, ca. 0.5 km before crossing with road to San Andres, rocky ridge surrounded by a laurisilva rich in Erica arborea , elev. 730 m (28º32’45’’N 16º13’00’’W), on S. fuliginosa , 19 July 2007, D. Ertz 10770 & P. Diederich ( BR-LICH 19-19); ibíd., P. Diederich 16517 ( MA); La Gomera, Parque Nacional de Garajonay, S of Alto de Garojonay, degradated laurisilva, elev. 1370 m (28º06’27.4”N 17º14’35.1”W), on S. limbata , April 2009, E. Sérusiaux ( LG); Santesson, Fungi Lichenicoli Exs. 201, La Palma, Cumbre Nueva, 1 km N of Refugio Forestal, in the outskirts of a Pinus canariensis forest, elev. ca. 1450 m (28º36’50”N 17º49’45”W), on S. limbata on the trunk of P. canariensis , December 1991, J. Hafellner 23524 (S-F30094); El Hierro, Frontera, Camino de San Salvador, laurisilva, elev. 1360 m (27º44’20”N 17º59’42”W), on Sticta sp. , 10 July 2011, S. Pérez-Ortega 3169 & M. Arróniz-Crespo ( MA); FRANCE. Bretagne: dep. Finistère, Forêt de Cranon, on S. fuliginosa on Quercus , 16 April 1931, G. Nilsson (Degelius) ( UPS F-156141); PORTUGAL. Azores: Terceira, SV om Aqualva, on S. limbata , 22 April 1937, H. Persson, det. G. Degelius ( UPS F-519425); Madeira: Vista Navios, 1.3 km SW of Poiso, elev. 1400 m, on S. limbata on Vaccinium maderense , 18 January 1969, L. Tibell 3257, det. R. Santesson ( UPS (L-118594)223971); USA. Alaska: Klondike Gold Rush National Historical Park, on S. limbata on dead Pinus contorta , 7 October 2007, T. Spribille 24949 (hb. Spribille); Alaska: Klondike Gold Rush National Historical Park, Chilkoot Trail, elev. 442 m (59º40.1829’N 135º15.8639’W), on S. limbata , 27 July 2008, S. Pérez-Ortega 3176, T. Spribille & T. TØnsberg ( MA); Alaska: Skagway, Yakutania area, mixed forest with Populus and Abies , elev. 8 m (59º27’9”N 135º20’8”W), on S. limbata on Populus sp. , 29 July 2008, S. Pérez-Ortega 3170 ( MA); ibid., S. Pérez-Ortega 3168 ( MA); Oregon: Lane Co., Dune wetland mosaic, often dense shrubs and broken Pinus contorta - Pinus sitchensis forest. BLM property, just inland from Heceta Beach, immediate coast, 2 km N of Florence, OR &. 5 km inland from ocean, elev. 3–15 m (T18S R12W S3 N1/2; 44º03’N 124º08’W), on S. limbata , 13 November 1994, R. Rosentreter, A. DeBolt, Hasselbach, Jonsson, Neitlich, McCune, Riley #9029, det. V. Alstrup as A. secedens (C); CHILE. Región de los Lagos, Isla de Chiloé, road between Chacao and Caulín, elev. 50 m (41º49’43”S 73º34’33’W), on Sticta sp. on dead trunks, 29 November 2009, S. Pérez-Ortega 3171 & J. Etayo ( MA); NEW ZEALAND. South Island, Cantebury, Hanmer State Forest, Hanmer Springs, Dog Stream (172º51’E 42º30’S), on S. limbata on Leptospermum ericioides , 12 September 1981, P.W.James, det. D.L. Hawksworth as A. parmeliarum s. lato ( BM 000731902); KENYA. Kenya colony, Aberdore Range, near the W part of the Nyeri track, elev. 3070 m. s.n., on Sticta sp. epiphytic on Stoebe kilimandscharica in the Hypericum -finge outside a patch of bamboo forest, 18 July 1948, O. Hedberg ( UPS); Mt. Kenya, eastern slope, Urumandi, elev. 3080 m (00º10’S 37º24’E), on Sticta sp. , 1959, M.J. Coe, det. R. Santesson ( UPS (F-156143)450268).

Figures

FIGURE 9. Abrothallus welwitschii (lectotype) on thallus of Sticta sylvatica. a: fragment of the lectotype; b: the handwritten herbarium sheet, the left specimen was selected as lectotype; c: ascus and ascospores of the lectotype specimen. Scale bar: c = 10 μm