Cryptogamie, Mycologie, 2009, 30 (2): 153-159 © 2009 Adac. Tous droits réservés Mycena subinsignis , a new species from highland heaths of Central Spain Fernando ESTEVE-RAVENTÓS* & José MaríaBARRASA Departamento de Biología Vegetal. Universidad de Alcalá E-28871 Alcalá de Henares, Madrid (Spain) Résumé – Mycena subinsignis sp. nov. est décrite d’une bruyère de montagne dans la province de Segovia au centre de l’Espagne et ou elle poussait sur litière d’Ericaceae . La nouvelle espèce est placée dans la section Insignes étant très proche de M. insignis , espèce américaine poussant sur litière de coniferes et dont elle differe par la taille des spores, l’absence de caulocystides, l’habitat et la distribution. Mycena section Insignes / Taxonomie / Morphologie / Distribution Abstract – Mycena subinsignis sp, nov. was found in a highland heath in the province of Segovia, Central Spain, fruiting on litter of Ericaceae . The new species is included in Mycena section Insignes being very close to the North American species M. insignis described from fallen conifer needles. Both species differ in the size of the spores, presence/absence of caulocystidia, habitat and distribution. Mycena section Insignes / Taxonomy / Morphology / Distribution INTRODUCTION During a field work of agarics in highland heaths of Central Spain, a new species of Mycena (Pers.) Roussel, here named M. subinsignis, was found fruiting on Ericaceae plant debris. This species was located in the Puerto de la Quesera, an area belonging to the mountain range of Ayllón, in the province of Segovia. This is a special site located at 1810 m above sea level, in the supramediterranean belt of the Mediterranean region (Rivas-Martínez, 1987), and is characterized by the presence of extensive heathlands that have been maintained by regular mists. This area is entirely covered by Erica arborea, E. australis , Vaccinium myrtillus and Arctostaphyllos uva-ursi shrubs that produce a noteworthy amount of organic material, suitable for fungal degradation. These particular high sites of Southern Europe are still incompletely known from a mycological point of view as also suggested by the recent description of two new Entoloma (Fr.) P. Kumm. from the same locality and type of habitat [ i.e. E. riofriense Esteve-Rav. & Noordel. and E. terreum Esteve-Rav. & Noordel. (Noordeloos, 2004)]. * Corresponding author: F. Esteve-Raventós, Departamento de Biología Vegetal, Universidad de Alcalá. E-28871 Alcalá de Henares, Madrid, Spain. Telephone: +34 918855058. Fax: +34 91 8855066. E-mail: [email protected] 154 F. Esteve-Raventós & J. M. Barrasa Recent phylogenetic analyses suggest that Mycena sensu Singer (1986) is a polyphyletic genus having its members separated in two clades: the “ mycenaceae ” and “ adonis ” clades (Moncalvo et al ., 2002). The genus comprises about 500 worldwide species (Kirk et al ., 2001) all saprophitic and growing on soil, rotten wood and plant litter. Maas Geesteranus (1992) divided the genus in different sections on the basis of macro- and micromorphological features, but new species and new sections continue to be described from Southern ( i.e. Moreno & Heykoop, 2000; Villarreal & Esteve-Raventós, 2000; Esteve-Raventós et al ., 2001 Villarreal et al., 2002; Robich, 2003; 2007) and Northern Europe ( i.e. Van den Berg et al ., 2000; Miersch et al ., 2006; Aronsen & Gulden, 2007; Aronsen, 2008). Section Insignes Maas Geest. (see Maas Geesteranus, 1989: 343) was typified by the American M. insignis A.H. Sm., and is characterized by the gelatinous covering of the stipe (without separable pellicle), the absence of a gelatinous matter in the hyphae of the subhymenium and by the broadly adnate to subdecurrent lamellae. Only five species [ Mycena insignis , M. odorifera Peck, M.pseudoclavicularis A.H. Sm., M.quiniaultensis Kauffman and M.roriduliformis (Murrill) Dennis] were included in this section by Smith (1947) and Maas Geesteranus ( loc. cit .), all of them fruiting on conifer litter in North America. Since then, three additional species ( M. demissa Maas Geest. & de Meijer, M.surculosa Maas Geest. & de Meijer and M. conspersa Maas Geest. & de Meijer) were described for this section from South America (Maas Geesteranus & de Meijer 1997), whereas M. tephrina Maas Geest. & E. Horak was described from Papua-New Guinea (Maas Geesteranus & Horak, 1995). For Europe, the only known species in section Insignes are the clampless M. calceata Robich (Robich 1996, 2003) and M. borellae Robich, which has broadly clavate, obtuse cheilo- and pleurocystidia and was found on fallen Picea twigs in Italy (Robich 2006). In summary, a total of twelve species (including M. subinsignis proposed in this work), have been placed in section Insignes , and all are characterized by the viscid pileus in wet conditions, the broadly adnate to subdecurrent lamellae without gelatinized edge and by the viscid stipe. Villarreal et al . (1999) transferred M. quiniaultensis and M. conspersa to section Fragilipedes (Fr.) Quél. based on the ascendant lamellae, and emended section Insignes to include only those species with arcuate to subdecurrent lamellae . Other related sections in Mycena are (1): sect. Fuliginellae (A.H. Sm. ex Singer) Maas Geest., which is characterized by species with a viscid separable pellicle on pileus, stipe and lamellar edge and (2): sect. Ingratae Maas Geest., which is characterized by free to almost free lamellae and the presence of loop- like clamps. MATERIALS AND METHODS A total of eleven fertile specimens of M. subinsignis , corresponding to three different collections (AH 26852, AH 30827 and AH 34357), were studied and deposited in the herbarium of Alcalá de Henares University (AH). Type material of M. insignis was borrowed from MICH (A.H. Smith 14071) and studied for comparison. Mycena subinsignis , a new species from Spain 155 Drawings of both species, M. insignis and M. subinsignis , were made with a camera lucida device coupled to an Olympus BX 50 microscope. Photographs of M. subinsignis were taken of fresh material and photographs of M. insignis were taken of dry material (holotype), using a Nikon F-601 camera with a high magnification objective. Colour of basidiomata was established according to Munsell (1994). Thirty spore measurements from at least one basidioma of each studied collections, were obtained to determine spore size following the Q method of Heinemann & Rameloo (1985). TAXONOMY Mycena subinsignis Esteve-Rav. & Barrasa, sp. nov . Figs. 1-5, 10 Basidiomata gregaria. Pileus 9-12 mm latus, convexo-campanulatus vel conico-convexus, leviter papillatus, plus minusve translucente striatus, glabrescens, leviter viscidus, pallido griseus vel cremeo-argillaceus, centro obscuriore. Lamellae 13-17 stipitem attingentes, late adnatae vel subdecurrentes, albidus vel argillaceus, arista concolora non gelatinosa. Stipes 25-30 × 1 mm, cylindraceus, glabrescens, viscidus, albidus vel pileo concoloris. Caro tenuis, albidus. Odore nullo vel leviter raphanoideo. Basidia clavata, 4-sporigera, fibulata. Sporae 7.7- 9.2 -10.7(-11) × 4-5 -6µm, Q = 1.53- 1.83 -2.14 (n = 30), ellipsoideae vel subcylindraceae, laeves, leviter amyloideae. Cheilocystidia 20-50 × 7-10 µm, sublageniformia vel lageniformia, interdum ad apicem furcata, in collum attenuata (1-2 µm lata), ad basim interdum lobulata, fibulata. Pleurocystidia nulla. Trama lamellarum leviter dextrinoidea. Hyphae pileipellis 2-3 µm latae, fibulatae, diverticulatae. Hyphae stipitis corticales 2-3 µm latae, fibulatae, diverticulatae, cellulae terminales cylindriceae. Caulocystidia nulla. Ad Ericaceae (Erica spp., Vaccinium myrtillus, Arctostaphyllos uva-ursi) sarmenta vel folia decisa. Hispania, Segovia, Puerto de la Quesera, 5 Nov 2004, AH 34357 (Holotypus). Basidiomata gregarious. Pileus 9-12 mm across, campanulate-convex at first, becoming widely conical to convex, with small but prominent obtuse umbo, often sinuose to crenulated at the margin, smooth to delicately pruinose, viscid when humid (but without separable pellicle), deeply translucent-striate for more than half the radius, greyish to grey-argillaceous or beige (Mu 2.5Y 8/1-8/2 to 7/1- 7/2), paler to cream or whitish towards the margin, becoming pale grey to cinereous in the herbarium. Lamellae rather distant, L = 13-17, with lamellulae (l = 1), narrow (– 2 mm), arcuate-decurrent with a tooth, whitish to beige-greyish, with concolorous, non-gelatinized edge. Stipe 25-30 × 1 mm, cylindrical, often flexuous or curved at the base, hollow, smooth to finely pruinose at the extreme apex, concolorous to pileus or watery white, surface viscid when wet, often with earth or vegetal debris adhering, arising from a whorl of agglutinated, white mycelial hyphae. Flesh very thin, whitish. Odour none to slightly raphanoid (in one collection). Basidia (20-)25-30(-38) × 8-10 µm, clavate, four-spored, with sterigmata 3-5 µm long, clamped at the base. Basidiospores 7.7- 9.2 -10.7(-11) × 4-5 -6 µm, Q = 1.53- 1.83 -2.14 (n = 30), ellipsoid to subcylindrical, with well marked apicula (sublacrymoid), smooth, weakly amyloid. Cheilocystidia 20-50 × 7-10 µm, forming a nearly sterile band, not embedded in gelatinous matter, lageniform, 156F. Esteve-Raventós & J. M. Barrasa Figs. 1-5. Mycena subinsignis (Holotype, AH 34357). 1 . Pileipellis. 2 . Basidium. 3 . Cheilocystidia. 4 . Basidiospores. 5 . Stipitipellis. Figs. 6-9. Mycena insignis (Holotype, A.H. Smith 14071). 6 . Pileipellis. 7 . Basidiospores. 8 . Cheilocystidia. 9 . Caulocystidia. Bar = 10 µm (longer bar only for spores). Mycena subinsignis