Excipulum plus minusve hyalinum, 20-30 um infra hymenium, 60-80 urn ad apicem, intus periphysibus usque 7 urn longis instructum. Hymenium 100-120 urn ...
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RAMONIA CALCICOLA, A NEW LICHEN SPECIES FROM CATALONIA, SPAIN The Karst region of Garraf in the NE of Spain is being investigated in detail as part of the doctoral thesis of the first author. In vertical cavities in the calcareous rock an interesting cryptogamic flora has been found. One of the lichens discovered is the new Ramonia described here. Ramonia calcicola Canals & Gomez-Bolea sp. nov. Thallus epilithicus, tenuis, ecorticatus, parce rimosus, viridulus vel subroseus. Algae ad Trentepohliam pertinentes. Apothecia semiimmersa vel superficialia, carnea, 0-2-0-4 mm lata, vertice apertura punctiformi demum gyalectoidea, margine aperturae stellato crenulato-lobulato, lobulis 3-5. Excipulum plus minusve hyalinum, 20-30 um infra hymenium, 60-80 urn ad apicem, intus periphysibus usque 7 urn longis instructum. Hymenium 100-120 urn altum, hyalinum, I — et KI —. Paraphyses simplices, apicibus leviter incrassatis, tubulis 1-5-2 pm crassis. Asci clavati vel plus minusve cylindrici, 90-100 x 12-16 urn, cum exoasco 1+ caerulescenti, 8-spori. Sporae fusiformes, 3-5(-7)-septa:ae, (17-)18-23(-26) x 4-6 urn, halonatae. Materia chemica: Thallus K, C, KC, et PD sine reactione. Typus: Spain, Catalonia, Barcelona, Begues (Baix Llobregat), avenc de la Morella, 560 m, ad saxa calcarea, UTM 31TDF0972, 27 July 1988, A. Canals, P. Navarro & A. Gomez-Bolea (BCC-Lich.5218—holotypus).
(Fig. 1) Thallus epilithic, ecorticate, homoiomerous, scarcely rimose or fissured, greenish or rosaceous. Photobiont Trentepohlia. Apothecia flesh-coloured, semi-immersed to superficial, 0-2-0-4 mm diam., at first with an entire minute pore, becoming ' gyalectoid ' with the pore widening to c. 0-3 mm diam., and with the margin radially splitting thus exposing the sunken, flesh-coloured disc. Excipulum ± hyaline, 20-30 |im below hymenium, c. 60-80 (am wide adjacent to the surface of the hymenium, composed of angular cells; this ' textura angularis ' is lost in KOH, inner surface lined with a palisade of periphyses, c. 5-7 x 2 urn. Hymenium hyaline, 100-120 |am tall, I —, KI — . Paraphyses unbranched, slender, to 1 -5-2 (im wide, apically slightly incrassate. Asci clavate to + cylindrical, 90-100 x 12-16 \im, apex rounded, wall thin, exoascus amyloid, without ring structure, 8-spored. Ascospores fusiform, (17-)18-23(-26) x 4-6 ^m, 3—5(-7)-septate, with a gelatinous perispore up to 3 [im wide. Chemistry: thallus K —, C —, KC —, PD —, U V + pink; two unidentified substances, by T L C , in solvent systems A, B and C (Culberson 1972), with Rf classes of 6, 6, 6 and 3, 5, 5 respectively. Distribution, habitat and ecology: At present, Ramonia calcicola is known from Spain where it is recorded from widely scattered localities in Catalonia and from one locality in Navarra (Dr J. Etayo, pers. comm.), and from France, in Languedoc and Provence (Bricaud & Roux 1991a) (Fig. 2). It grows on vertical, shaded walls of calcareous rocks, in the vertical karstic cavities. In this habitat a vertical gradient of light intensity, air humidity and temperature is found. The light intensity diminishes with depth down to the photosynthetic compensation point of the more sciaphytic lichens and algae. The air humidity
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• FIG. 1. Ramonia calacola. A, Vertical section of apothecium. B, Detail of a part of the excipulum, showing periphyses. C, Ascus. D, Paraphyses. E, Ascospores. Scales: A = 50nm; B, C, D & E =
increases steeply to virtual saturation (90-100° 0 ). The temperature, broadly oscillating in the mouth of the cavity, becomes more and more stable, around 14-15 C. These gradients cause a horizontal zonation in the distribution of the photosynthetic organism. We have distinguished three zones with algae and lichens. Ramonia calcicola inhabits the intermediate one, where the biggest thallus (up to 100 dm2) could be seen, thriving along with other epilithic, Trentepohlia-beanng lichens, namely: Strigula taylorii, S. calcarea (Bricaud & Roux 19916), Porina cf. oleriana, P. cf. byssophila, Opegrapha mougeoti, O. variaeformis, Verrucaria glaucodes and Encephalographa elisae. Remarks: This new species shares many essential characters with the type species of the genus, Ramonia valenzueliana (Mont.) Stizenb. (Vezda 1966, 1967, 1973). The most recent circumscription of Ramonia (Coppins 1987) is more restrictive than that of Vezda (1966), and some characters we observed fall outside this most recent delimitation. Thus, in R. calcicola, the ' textura
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FIG. 2. Distribution of Ramonia calcicola. In France, data from Cl. Roux. In N Spain, data from J. Etayo.
angularis ' is lost in KOH, whereas in Ramonia, sensu Coppins, the exciple structure is not altered by KOH (Coppins, pers. comm.). The K/I+ blue reaction of the hymenium (Vezda 1966; Coppins 1987) does not occur in our species. We have decided to keep the new species in the genus Ramonia because we find that the characters discordant with the most recent delimitation (Coppins 1987) are not important enough to create another genus. In the future, new studies devoted to the tropical species of Ramonia may be very helpful for a more thorough comprehension of this genus. The main differences between this genus and Petractis, Cryptolechia, Gyalecta and Pachyphiale are the presence of periphyses and angular cells in the apothecia of Ramonia only. Ramonia luteola Vezda is very close to R. calcicola, but the main differences are in the periphyses (12(j.m long), the hymenium (60-70 urn tall, 1+ blue), the ascospores (20-27 x 4—6 urn, (3-)7-septate) and the ecology (epiphytic), in the first species. This new taxon is the first saxicolous Ramonia reported from Europe. Additional specimens examined: Spain: Catalonia: Barcelona, Begues (Baix Llobregat), avenc de la Papellona, UTM 31TDF0871, 503 m, 27 July 1988, A. Canals, P. Navarro & A. Gomez-Bolea (BCC-Lich.5219); Sitges (Garraf), avenc de la Riera de la Falconera, UTM 31TDF0767, 68 m, 5 November 1989, A. Canals (BCC-Lich.5220); Vallirana (Baix Llobregat), avenc dels geolegs, UTM 31TDF0580, 430 m, 12 May 1990, A. Canals (BCC-Lich.5221). We are very grateful to Drs A. Vezda, B. J. Coppins, Cl. Roux and J. Etayo for their helpful comments, to Dr X. Llimona for his comments on our manuscript, and to Dr O. de Bolos for revising the Latin diagnosis. We are also obliged to the Comision Asesora de Investigacion Cientifica y Tecnica, Project no. PB89-0518-C02-01, for thefinancialsupport. REFERENCES
Bricaud, O. & Roux, C. (1991a) 'L'Encephalographetum elisae Bricaud et Roux ass. nov., une association lichenique saxicole-calcicole, sciaphile. Bulletin de la Socie'te linne'enne de Provence 42:79-90.
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Bricaud, O. & Roux, C. (19916) Strigula calcarea Bricaud et Roux sp. nov., espece nouvelle de lichen. Bulletin de la Socie'te linneenne de Provence 42: 131-139. Coppins, B. J. (1987) The genus Ramonia in the British Isles. Lichenologist 19: 409-417. Culberson, C. F. (1972) Improved conditions and new data for the identification of lichen products by a standardized thin layer chromatographic method for lichen products. Journal of Chromatography 72: 113-125. Vezda, A. (1966) Flechtensystematische Studien III. Die GattungenRamonia Stiz. und Gloeolecia Lett. Foliageobotanica eiphytotaxonomica 1: 154-175. Vezda, A. (1967) Flechtensystematische Studien V. Die Gattung Ramonia Stiz. Zusatze. Folia geobotanica et phytotaxonomica 2: 311-317. Vezda, A. (1973) Flechtensystematische Studien IX. Die Gattung Ramonia Stiz. Zusatze. 2. Folia geobotanica et phytotaxonomica 8: 417-424.
Antonio Canals* and Antonio Gomez-Bolea* *Department of Botany, Faculty of Biology, University of Barcelona, Diagonal 645, E-08071 Barcelona, Spain.
