(Lichenicolous Roccellaceae, Ascomycota) on Peltigera

The Bryologist 106(3), pp. 465 467 Copyright ᭧ 2003 by the American Bryological and Lichenological Society, Inc.

A New Species of Plectocarpon (Lichenicolous Roccellaceae, Ascomycota) on Peltigera

DAMIEN ERTZ National Botanic Garden of Belgium, Domaine de Bouchout, B-1860 Meise, Belgium; e-mail: damien.ertz@br. fgov.be

MIKHAIL ZHURBENKO Laboratory of the Systematics and Geography of Fungi, Komarov Botanical Institute, Russian Academy of Sci- ences, Professor Popov 2, 197376, St.-Petersburg, Russia; e-mail: [email protected]

PAUL DIEDERICH MuseÂe national d'histoire naturelle, 25 rue Munster, L-2160 Luxembourg, Luxembourg; e-mail: paul.diederich@ education.lu

JOLANTA MIADLIKOWSKA Department of Biology, Duke University, Durham, NC 27708, U.S.A. e-mail: [email protected]

Abstract. A new lichenicolous species, Plectocarpon peltigerae, growing on Peltigera leucophlebia thalli, is described from Canada and Russia.

Plectocarpon FeÂe is a widespread lichenicolous more convex central part by circular depression; the genus containing at least 15 species, growing main- upper surface of central part of ascomata, including ly on Peltigerales (Diederich & Etayo 1994). A new young ones, strongly verrucose, each verruca con- species apparently con®ned to Peltigera leucophle- taining fertile perithecium-like loculus soon ex- bia is described here from Canada and Russia. posed through irregular punctiform or more often elongate opening, giving appearance of agglomer- MATERIAL AND METHODS ation of lirellae-like ascomata; external ring often

We have studied specimens from DUKE and LE. Hand- developing into verrucose, lirellae-like structure made sections were examined in water, 5% KOH (K), containing perithecia-like loculi; in poorly devel- Congo Red with KOH pre-treatment, or Lugol's reagent oped specimens, ring often missing or incomplete. without (I) or with KOH pretreatment (K/I). Measure- Ascomata in section initially showing continuous ments of asci and ascospores all refer to material exam- host cortex of cells that turned reddish brown, ined in KOH; those of ascospores do not include the per- Ϯ ispore. Drawings were done using a drawing tube. intact host photobiont layer, and numerous round- ish, fertile, immersed perithecia-like loculi, up to PLECTOCARPON PELTIGERAE Zhurb., Ertz, Dieder- 200 ␮m in diam. and 120 ␮m in height, generally ich & Miadl., sp. nov. FIGS 1±2 well separated from each other, surrounded by brownish to olivaceous, KϪ excipular layer; when Ascomata lichenicola, convexa, atra, verrucosa, 0.3± mature, the excipular tissue enlarges and host cor- 0.9(±1.5) mm diam., plurilocularia, loculis ad 200 ␮m tex becomes darker brown, giving appearance of diam., ad 120 m alta. Textura stromatica atrorufa, cum ␮ thick, dark brown to black multilocular stroma, pigmento olivaceo, KϪ. Asci 4(8)±spori, 40±58 ϫ 12±19 ␮m. Ascosporae 3-septatae, 18±22 ϫ 4.5±6.5(±7.0) ␮m. 140±220 ␮m thick. Hymenium hyaline, pale brown- Conidia 4.5±5.5 ϫ1.0±1.5 ␮m. ish to olivaceous, entirely ®lling loculi, Iϩ red, K/

TYPE: CANADA. BRITISH COLUMBIA. Spahats Creek, 10 I ϩ blue. Paraphyses abundant, anastomosed, 1.8± km N of Clearwater, Wells Gray Provincial Park, Trophy 2.3 ␮m in diam., apically not distinctly swollen. Mtn trail, Miadlikowska 08.29.00±5 (DUKE, holotype; BR, Asci of the Opegrapha-type, wall IϪ and K/IϪ, ex- hb. Diederich, isotypes). cept for a K/Iϩ blue apical ring, with distinct ocular Ascomata black, stromatic, gall-forming, dis- chamber, claviform, generally 4-spored, although tinctly convex but not constricted at base, 0.3±0.9(± asci with eight young spores have been observed, 1.5) mm in diam., developing in center of dark 40±58 ϫ 12±19 ␮m. Ascospores narrowly ellipsoid, brown circular areas of thallus, dispersed, often 3-septate, slightly constricted at septa, hyaline, con¯uent and covering larger parts of host thallus; 18.0±22.0 ϫ 4.5±6.5(±7.0) ␮m, with a distinct per- when well developed, often dividing into Ϯ ¯at ex- ispore 0.5±1.0 ␮m thick (in KOH). Pycnidia inter- ternal ring that is usually clearly separated from mixed with the ascomatal loculi and indistinguish-

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FIGURE 1. Plectocarpon peltigerae (holotype). Ð A. FIGURE 2. Plectocarpon peltigerae (holotype). Ð A. Ascus with four ascospores. Ð B. Ascospores. Ð C. Co- Thallus of Peltigera leucophlebia with numerous ascom- nidia. All drawings in K/I. ata. Ð B. Ascoma. Scale bars: A ϭ 1 mm, B ϭ 250 ␮m. able from them externally. Conidia bacilliform, aseptate, hyaline, with a truncate base, 4.5±5.5 ϫ Plectocarpon lambinonii Diederich & Etayo is dis- 1.0±1.5 ␮m. tinguished by more strongly convex galls, mostly Distribution and host. Known from Canada 2-spored asci, and a Kϩ green stromatic pigment (British Columbia) and Russia (Komi Republic: (Diederich & Etayo 1994). Plectocarpon arthon- Northern Ural; Karelia Republic: Keret' Archipel- ioides Diederich has shorter ascospores, 15.5±17.0 ago in the Kandalaksha Gulf of the White Sea) on ϫ 5.0±5.5 ␮m that are six per ascus (Aptroot et al. Peltigera leucophlebia (upper surface of thallus, 1997). rarely also on corticated patches on the underside The species might be confused with Arthonia of apothecia), not obviously damaging the host. fuscopurpurea that has ascomata of a similar size, The hosts of the Canadian collections might rep- also growing on Peltigera. However in that species, resent a distinct, possibly new species of Peltigera the ascomata are more ¯attened and reddish closely related to P. leucophlebia; their identity is brownÐnot black, the asci are of the Arthonia- currently being investigated by JM. type, and the ascospores are 1-septate. Discussion. This is the ®rst known species of Plectocarpon growing on Peltigera. It is distin- Paratypes (all on Peltigera leucophlebia).ÐCANADA. BRITISH COLUMBIA. Spahats Creek, 10 km N of Clearwater, guished from all other known species of the genus Wells Gray Provincial Park, near Spahats Creek Falls, by the special ascomata, in which when well de- 51Њ44Ј N; 120Њ01Ј W, 710 m, Miadlikowska 08.07.02±22 veloped, an outer fertile ring is separated from the & Zhurbenko 02209, 02215, 02217, 02218, 02237, 02257, central, also fertile part by a circular depression sur- 02266 (DUKE; LE; hb. Diederich), near S boundary of Park, rounding that center. This ring is best seen in the Murtle River Trail NE of Dawson Falls, 51Њ58Ј N; 120Њ06Ј W, 730 m, Zhurbenko 02239 (LE), Clearwater River Trail, type specimen, but poorly developed or absent in 51Њ43Ј N; 120Њ01Ј W, 550 m, Zhurbenko 02282 (LE), Phil- other specimens. Furthermore, the fertile loculi be- ip Creek Trail, 52Њ52Ј N; 120Њ00Ј W, 800 m, Zhurbenko come exposed following a slit-like opening, and the 02160 (LE). RUSSIA. KARELIA REPUBLIC. Loukhi District resulting mature ascomata appear as covered by a (ϭ Karelia Keretina), Keret' Archipelago in the Kanda- laksha Gulf of White Sea, Srednii Island, 66Њ17Ј N, 33Њ38Ј number of radiating or irregularly disposed lirellae. E, 10 m, Himelbrant, 2000 (LE). KOMI REPUBLIC. Troitsko- In none of the other known species of Plectocarpon Pechorskii Region, Northern Ural, headwaters of Pechora have such lirelliform structures been observed. River, Pechora-Ilych State Reserve, 125 km SE of Troit- 2003] ERTZ ET AL.: PLECTO CARPON ON PELTIGERA 467 sko-Pechorsk, Sobinskoe, 61Њ59Ј N; 58Њ02Ј E, elev. 160 LITERATURE CITED m, Zhurbenko 97253 (LE, hb. Diederich). APTROOT, A., P. DIEDERICH,E.SEÂ RUSIAUX &J.M.SIPMAN. 1997. Lichens and lichenicolous fungi from New ACKNOWLEDGMENTS Guinea. Bibliotheca Lichenologica 64: 1±220. DIEDERICH,P.&J.ETAYO. 1994. Taxonomic notes on the This project was funded in part by a grant from the genus Plectocarpon (lichenicolous Ascomycotina). National Science Foundation DEB-0133891 to FrancËois Nordic Journal of Botany 14: 589±600. Lutzoni. The authors are indebted to Michal Skakuj for the drawing included in this article and to Dmitrii Himel- brant for the permission to publish his specimen of the new species. ms. received Nov. 19, 2002; accepted March 14, 2003.