Mireia Giralt

Studies on Some Species of Arthothelium Occurring in the Western Mediterranean

We present a survey of the six known species of Anhothelium occurring in the western Mediterranean. The oceanic A. lirellans , which may occur in the study area, is included for comparison; A. taediosoides is described as new and a key to all species is given. Anhothelium as understood today is composed of more-or-less distinct natural groups of species, some of them being compared here. Representatives of the A. sardoum group are related to species of the Arthonia radiata or A. galactites group on the basis o anatomical characters of the ascomata.

Endohyalina , the genus in the Physciaceae to accommodate the species of the Rinodina ericina -group

The genus Endohyalina is characterized by crustose, autonomous, or obligately lichenicolous thalli, lecideine apothecia with a hymenium often more or less inspersed with oil droplets and a brown hypothecium, Bacidia-type asci, small Dirinaria-type ascospores developing with type B ontogeny, bacilliform conidia and containing diploicin as the major secondary metabolite. The genus is based on four species previously included in Rinodina—R. ericina s. lat., R. insularis, R. interjecta and R. kalbii—and on two lichenicolous species from the Canary Islands described here as new, Endohyalina brandii and E. diederichii. The generic type, Endohyalina rappii, is reduced to synonymy with E. ericina whereas E. circumpallida is excluded from the genus and returned to Buellia s. lat. Except for the thalline growth form and the common lichenicolous habit, the diagnostic characters of Endohyalina are akin to those of Diploicia. New chemical data on Endohyalina insularis and E. kalbii are reported, and a simple method for determining the secondary chemistry of lichenicolous fungi is provided.

New data for Rinodina flavosoralifera

Well-developed ascospores of Rinodina flavosoralifera have been observed for the first time. The ascospores are described and illustrated and new data on the chemistry and distribution of this species are provided. New chorological data on Rinodina disjuncta are also included.

Buellia tesserata and Dimelaena radiata, two closely related species

The morphology, anatomy, ecology and distribution of Buellia tesserata and Dimelaena radiata are discussed. New data on their chemistry are given. The present study reveals a very close relationship between both taxa and consequently their di#erent generic position is questioned. Buellia fimbriata is reduced to synonymy with Buellia tesserata.

The genus Buellia s.l. and some additional genera of Physciaceae in the Canary Islands

The Buellia s. lat. species that occur in the Canary Islands are described including the related genera Amandinea, Diplotomma and Tetramelas. Species of the genera Coscinocladium, Dimelaena and Diploicia are also included. Forty-one species have been identified. Nine species are new records for the archipelago. The study of the type specimens and additional material of Buellia caloplacivora, B. sequax and B. leptina demonstrated that the two former are not conspecific and that the third is a valid taxon. The new combinations Buellia gomerana and Buellia alisioae are proposed. A short description, including the chemistry, ecology and distribution of all taxa is provided. A key to the species known to occur in the study area is also included.

The identity of Buellia sequax

The study of the type specimens of Buellia sequax revealed that the current concept of this species is erroneous and instead corresponds to B. abstracta. By contrast, B. sequax s. str. is characterized by the same diagnostic characters as presently accepted for B. excelsa. Consequently, they represent one and the same taxon. Since B. sequax is the older name, B. excelsa is reduced to synonymy. Buellia lepidastroidea is also reduced to synonymy with B. sequax s. str. Buellia sequax s. str. (= B. excelsa and B. lepidastroidea) contains diploicin and atranorin, has a hymenium inspersed with oil droplets, and ascospores which develop with type-B ontogeny. This combination of characters suggests that B. sequax s. str. is closely related to the genera Diploicia and Endohyalina but B. boergesenii does not belong to this group. New data on the chemistry and distribution of B. sequax s. str. are provided and amended descriptions of this species and B. abstracta (= B. sequax auct.) are presented.

Rinodina etayoi, a new saxicolous lichen species from the Canary Islands

The silicicolous lichen species, Rinodina etayoi Giralt & van den Boom, is described as new from inland localities of Fuerteventura and Lanzarote (Canary Islands). It is characterized by a crustose, whitish thallus containing atranorin, zeorin, chloroatranorin and stictic acid, hemispheric pseudolecanorine apothecia containing, a proper exciple inspersed with numerous and large oil drops, and by ascospores of the Mischoblastia -type. The joint occurrence of pannarin, stictic acid and Mischoblastia -type ascospores makes R. etayoi unique within the genus.

Tetramelas thiopolizus comb. nov. with a key to all known species of Tetramelas

The study of the type and additional material of Buellia andicola, B. hypophana and B. reagens has shown that these taxa are conspecific with B. thiopoliza. Buellia thiopoliza is a muscicolous species growing at middle to high altitudes in the mountains of both hemispheres. It is easily recognized by its K+ purple-red yellow pigment mainly concentrated in the hypothecium, and by the presence of xanthones in the thallus and the apothecial tissues. The new combination Tetramelas thiopolizus is proposed. A key to all known Tetramelas species is included. The also muscicolous Buellia hypoleuca is reduced to synonymy with Phaeorrhiza sareptana var. sphaerocarpa.

''Buellia'' lindingeri and Rinodina hallii (Physciaceae), two closely related species

Abstract A comparative study of the morphology, anatomy and chemistry of Buellia lindingeri and Rinodina hallii clearly shows that these taxa are very closely related but not conspecific. The unique epihymenia distinguishes them from most species of both Buellia and Rinodina but, as they are more closely related to Rinodina, Buellia lindingeri is transferred to that genus.

Rinodina fuscoisidiata, a new muscicolous, isidiate species from Venezuela

Rinodina fuscoisidiata , a muscicolous isidiate species with large isidia and Pachysporaria -type ascospores is described from Venezuela. This species contains an unknown terpene as a major secondary metabolite in addition to traces of atranorin. It is compared with the four known isidiate Rinodina taxa.