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THE LICHENS and lichenicolous fungi OF SARDINIA (Italy) an annotated list by P. L. NIMIS & J. POELT With contributions of O. BREUSS (Wien) W. BRUNNBAUER (Wien) P. CLERC (Bern) J. HAFELLNER (Graz) H. HERTEL (Munchen) P.W. JAMES (London) M. MAYRHOFER (Graz) H. MAYRHOFER (Graz) C. LEUCKERT (Berlin) C. SCHEIDEGGER (Bern) A. VEZDA (Brno) Published by the University of Trieste in occasion of the XIV lnternational Botanical Congress Berlin (West) 1987 Excursion Nr. 49 to Sardinia Dedicated to the memory of: F. BAGLIETTO G. DE NOTARIS A. MASSALONGO lntroduction In early 1985 the authors planned to organise a lichenological excursion to Sardinia as a part of the excursion programre for the XIV International Botanical Congress (Berlin, July 1987). The island of Sardinia was chosen because of its great phytogeographical interest: It lies in the centre of the western Mediterranean Basin and has a great variety of geological . substrates. As rrost parts of the Mediterranean region, Sardinia is relatively poorly known fran a lichenological point of view. In order to organise the excursion, field-trips to Sardinia were carried out in Sumner 1985 and in Spring 1986. On these occasions extensive collections were made fran several parts of the island; the identifications resulting fran this material provided a preliminary list of taxa. Further additions caire fran colleagues who had already visited the island, fran exsiccata in herbaria, fran scarce literature records and, above all, fran the herbariun Baglietto (MJD), where rrost of the sarrples cited by BA.GLIETID (1879) in his first and seminal catalogue of lichens of Sardinia are preserved. The present work includes a critical revision of the lichens known fran Sardinia. The Mediterranean region is arrong the lichenologically least studied parts of Europe and, as a consequence, the circunscription of many taxa is not yet clear, and the distribution and ecology of many species are badly known. It was obviously irrpossible for us to solve all these problems; in the short notes appended to each taxon we often either draw attention to the existence of problems, or give sane general information on the distribution and ecology of the taxa, with particular regard to Italy, the lichen flora of which is one of the rrost poorly known in Europe. Many collections at our hane institutions still remain unidentified because of taxonanic difficulties, which cannot be solved in a reasonably short time. The nurber of taxa at specific and varietal level listed in this book is 901. It is certain that the lichen flora of Sardinia is much richer, and that much rrore profitable work can be carried out in the lichenological exploration of the island. In spite of- its incarpleteness,we decided to publish this annotated list in order to provide a m:xlern review of lichenological research in Sardinia, which might act as a reference point for future studies. We hope that in time this book will becane outdated, revealing its shortcanings, not least as a consequence of the International Excursion itself; this would be an indication that it actually fulfilled the role for which it has been published. 1 The natural environment of Sardinia Geography The island of Sardinia lies in the centre of the western Mediterranean ° ° sea, between 38 51' 52" and 41 15' 42" lat. north (Capo Teulada-P.ta ° ° Falcone) and between 8 8' and 9 5' long. east (Capo dell'Argentiera-Capo Canino). lts shape is approxirnately rectangular, with the longest sides disposed in a north-south direction. The distance between the northern and southern extremities is of ca. 270 Km, the average distance between the eastern and western coasts of ca. 145 Km., with a minimun of 96 Km in the narrowest portion between Oristano and Barisardo. Sardinia, with a surface area of 24.089 Kmq is the second largest island of the Mediterranean sea. Although the maxinun elevation is only of 1834 m (P.ta Lam3rroora, Gennargentu), the landscape of the island is characterized by very rugged gearorphological features, with a prevalence of mountains. The only extensive plain is the Carrpidano region, extending fran the gulf of Cagliari to the gulf of Oristano in a southeast-northwest direction for approxirnately 100 Km. This plain separates the mountains of the southwest (M. Linas, 1236 m) fran a mountain area extending over the central and eastern parts of the island, whose highest peaks are M. Lirrbàra in the north ( 1362 m), the Gennargentu Massif in the centre (1834 m) and P. ta Serpeddi' in the south (1062 m). In sane areas, especially the Barbagia region, the different massifs are separated by narrow, deep gorges, which have made access very difficult in the past. Peculiar geanorphological features are the "Giare" of central-eastern Sardinia,, extended plateaus with steeply declining margins consisting of effusive rocks (mainly basalt), and the "Toneri", conical structures derived fran the erosion of a dolanitic limestone cover. The most inportant rivers (Tirso, Flunendosa, Fllll1ini Mannu, Coghinas) originate in the high mountains of the province of Nuoro. Many of the smaller rivers dry out more or less conpletely during surrner. There is only one natural lake, Lago di Baratz in the Nurra region, but a great nurber of artificial lakes are scattered throughout the island. The coastline, including the satellite islands, is 1897 Km long. The aàninistrative subdivision of Sardinia in four Provinces (Cagliari, Nuoro, Oristano, Sassari) doe� not always reflect a natural articulation of the island on a geographical or ethnological basis. Of more interest is the traditional subdivision in historical-geographical districts, which often include areas fonnally belonging to different aàninistrative provinces. The main districts are shCMn in Fig. 1. 2 "' V> "P gr � -p :,> !J'/-'-\>- "' 1>,'1-'o o li; "P ;il o G' :,> TREXENTA ,, ,-0 ,,- GERRE! -,, SARRABUS o () Fig. 1 - Main historical districts of Sardinia. Ge ology Geologically, Sardinia little reserrbles continental Italy; the geologicai history of the island has been very different fran that of the Alps and Apennines, and the island, as the island of Corsica, has a much rrore ancient origin. One of the main geoiogicai characters which may be of interest for the lichenoiogist is the great variety of rock-types occurring on the is iand, fran Carrbrian to Quatemary e ras; in generai, siiiceous rocks (of very different types) are rrore ccmnon than limestone or other calcareous rocks; the distribution of the main rock-types on the isiand is shown in Fig. 2. Sardinia is ccrrposed of a Palaeozoic infrastructure and a Mesozoic and Cenozoic cover. The oidest outcrops, consisting of a succession ranging from the looer Carrbrian to the iower Carboniferous, has been affected by an intense regionai metarrorphism. From the normai or bareiy epimetarrorphic sediments in soutrnestern Sardinia there is a transition to phyiiites, to mica-schists, to gneisses and then to magmatic-anatectic granites in northeast Sardinia (CHARRIER, 1958; VARDABASSO, 1966; mNTI & TRAVERSA, 1968, CIYJJUA, 1975). The oldest layers of the Paieozoic sequence do not outcrop, with the exception of a small ·area close to Capo Spartivento (CIYJJUA,1975). The 3 4 Fig. 2 - Main rock types in Sardinia a) limestone b) sandstone, marls e) granite d) metamorphic rocks e) lavas, tuffs t) basalt 5 oldest extensive outcrops are in the lglesiente-Sulcis region; they range fran the lower Carrbrian to the lower Carboniferous. Volcanic activity in this area was not strong, and acid volcanic rocks are not known in the lglesiente-Sulcis region. Another region with very old outcrops is the area situated to the northeast of Carrpidano, i.e. the vast region north of a line joining Capo Frasca on the west with Sarrabus--Gerrei in southeast Sardinia. The sediments are characterized by a succession of prevalently terrigenous rocks with the sedimentological characteristics of Flysch. Volcanic activity started with aerial eruptions of porphyries and continued throughout the Silurian with frequent and thick subacqueous porphyric eruptions (PCMESANO CHERCHI, 1982; CALVOO, 1961). To the Hercynian cycle belong the extensive granitic fonnations, which are roost frequent in the northeastern, central and southeastern parts of the island. At the end of the Hercynian cycle Sardinia, or better the Corsica-Sardinia massif was corrpletely emerged and still attached to the French-Spanish coast (DUOOURDIEU, 1962; DERCX)lJRT, 1970). This position probably linked the Corsica-Sardinia massif with an approximately east--west alignement to the lberian massif (a:xJJZZA., 1975). At the end of the l!ercynian cycle a long period of orogenic quiet began in Sardinia, with only minor roovements of slow subsidence. These conditions persisted through the Mesozoic and Cenozoic, permitting the ingression of epicontinental seas in sare sectors of the island. At the end of the Cuisian the ancient dislocation lines were reactivated with differential uplift of the various blocks into which the Sardinian massif was already divided. These movements produced gravity slides with local overthrusting and pseudo-reverse faulting as in the calcareous Monti di Oliena, M. Albo etc. In the middle-upper Oligocene the tectonic roovements reached their maximum intensity, leading to an intense volcanic activity of prevalently andesitic and rhyolitic type (LAURO & DERIU, 1957). The lavas and pyroclastic products of this activity accunulated mainly in tectonic depressions. In the Miocene the sea returned once more to the island, but occupied only the tectonically depressed areas, including a low area that existed at that time between Sardinia and Corsica, perhaps separating them for the first time. At the end of Miocene there was a phase of adjustement followed in the Pliocene by basaltic volcanism (e.g. Giara di Gesturi). The geological evolution of , Sardinia is thus characterized by a whole series of progressively shorter sedimentary cycles, which were interrupted by marked discordances; the present facies are prevalently of epicontinental or continental envirorment, notwithstanding the scarcity of carbonatic and evaporitic rocks (a:xJJZZA., 1975).