Contribución al Conocimiento de los Líquenes Calcícolas del Occidente de Vizcaya y Parte Oriental de Cantabria (N-España) [Contribution to the Knowledge of the Calcicultural Lichens of the West of Vizcaya and the Eastern Part of Cantabria (N-Spain)]

The calcicolous lichen Flora in a part of Northern Spain comprising part of the Basque Country (W-Vizcaya) and the Eastern part of the nearby Cantabria is studied. The zone falls within the Atlantic-Cantabrian Province of the Eurosiberian Region. Its general climate is temperate oceanic, and the ombroclimate humid to hiperhumid. Altitudes range between the sea level and 1360 m. The studied sites comprise both the colline and the montane bioclimatic belts. The first one includes the lichen populations from the littoral (sites 1-5 and 13-15) and the calcareous outcrops of Mt. Candina (sites 7-9), peñas de Ranero (site 22), and Trucíos (site 21). In the montane bioclimatic belt we have studied mainly the Mt. Alén (site 19) and the Mt. Gorbea range (sites 23-29). The studied substrata are calcareous outcrops from the Lower Cretacic Period: mainly hard limestones, but also some softer, loamy limestones as well as recrystallized limestones and mortar are included. These three last types are noteworthy because of their greater water-retention capacity.

Results are presented in the form of a commented catalogue which includes 227 taxa, of which 210 are lichenized fungi (205 species, plus 1 subspecies, 3 varieties and 1 form), while the other 17 species are lichenicolous fungi. Most of the taxa belong to the Orders Lecanorales (87 species : 29 genera : 12 families), Verrucariales (59 species : 12 genera : 1 family) and Teloschistales (32 species : 2 genera : 1 family). Verrucariaceae and Teloschistaceae are the families with the greatest species number. For each taxon, the author discusses the autoecology and the known distribution in Spain. Morphological descriptions and illustrations based on our studied material are provided for the lesser known taxa. Identification keys in the genera Caloplaca, Polyblastia, Staurothele, Thelidium, and Verrucaria are presented.

Approximately 72 % of the taxa have a wide distribution range, being cosmopolitan, holarctic or eurosiberian. Up to 12 % are mediterranean elements, which can be divided in two groups: the eumediterranean and the latemediterranean ones. The first group are restricted in our study zone to sites near the sea, in the so called thermocolline bioclimatic fringe, and comprise the following: Arthonia meridionalis, Caloplaca biatorina var. gyalolechioides, Candelariella oleaginescens, Dirina massiliensis f. massiliensis, Encephalographa elisae, Petractis thelotremella, Toninia albilabra and Verrucaria cazzae. In the second group, with a wider distribution in our zone, includes the following: Aspicilia cheresina var. cheresina and var. justii, Aspicilia coronata, Buellia sequax, Caloplaca erythrocarpa, Caloplaca inconnexa, Caloplaca polycarpa, Candelariella medians, Collema fragile, Dirina massiliensis f. sorediata, Lecanora pruinosa, Porina oleriana var. ginzbergeri, Roccella phycopsis, Staurothele immersa, Staurothele orbicularis, Toninia diflracta, Verrucaria fuscula, Verrucaria lecideoides and Verrucaria parmigerella. About 7 % are orophile elements which appear locally in the montane bioclimatic belt: Arthopyrenia saxicola, Buellia subdispersa, Caloplaca cerina var. ochroleuca, Caloplaca nubigena var. keissleri, Dermatocarpon intestiniforme, Farnoldia jurana, Hymenelia carnulosa, Hymenelia epulorica, Lecanora agardhiana subsp. sapaudica, Lecidella patavina, Polyblastia cupularis, Rhizocarpon umbilicatum, Sarcogyne fallax, Solorina bispora, Verrucaria cinereorufa var. clauzadei and Verrucaria tristis.

Especially noteworthy are several taxa which are known from few and scattered localities in Europe. Here this includes Buellia scheideggeriana, Lecanora efiigurascens, Lemmopsis arnoldiana, Placopyrenium subtrachyticum, Pyrenocollema caesium, Staurothele nantiana, Thelidium dionantense, Verrucaria glaucodes, Verrucaria helveticorum, Verrucaria hladuniana and Verrucaria lilacina. Two species, Catapyrenium pyrenaicum and Thelopsis foveolata, are for the moment endemic to the zone and (the first one) to the western Pyrenees. The author also includes one taxon, Buellia lecanoricola ined. (Sect. Diplotomma), parasitic on Lecanora albescens, which will be formally described as new species when the opportunity to study more material arises.