Five species of Candelaria and Candelariella (Ascomycota, Candelariales) new to Switzerland

Candelaria pacifica, Candelariella antennaria, C. boleana, C. granuliformis and C. xanthostigmoides are reported from Switzerland for the first time. Candelariella xanthostigmoides is also new to Europe. Candelariella aggregata, C. efflorescens, C. subdeflexa and C. viae-lactea are confirmed to occur in Switzerland. Candelariella antennaria is also reported new to Austria. Brief notes on their identification, ecology and distribution in Switzerland are given.


Introduction
Candelariella is a well-known and commonly occurring genus, growing on many types of substrates, particularily in exposed and nitrogen-enriched localities.The species of the genus are a prominent component of the lichen flora on e.g., road-side trees, limestone rocks and in alpine, terricolous habitats.However, the knowledge of the distribution and ecology of individual species is still poor for many species.It appears that few lichenologists collect and study Candelariella, possibly because of the presumed difficulties in correctly identifying the species.In Switzerland, a large number of recent collections of Candelariella exists due to field work done in the framework of the Red List of threatened and rare epiphytic and terricolous lichens in Switzerland (Scheidegger and Clerc 2002).Part of this study led to the first terricolous lichen inventory in Switzerland where all vegetated landscapes were explored between 1996 and 1997 (Vust 2011).A detailed revision of the herbarium material filed under Candelariella and Candelaria at the Conservatoire et Jardin botaniques de la Ville de Genève (G), revealed six new species to Switzerland not mentioned in the recent checklist of the Swiss lichens (Clerc and Truong 2010).One of these, C. aggregata, was recently reported for Switzerland (Spinelli 2011) and the remaining species are reported here with brief descriptions of important characteristics of the species together with notes on their ecology and distribution in Switzerland.One of the species, C. antennaria is also reported new to Austria.We want to emphasize that many species can be readily identified.Collecting and studying them is a rewarding effort as there are many interesting discoveries to be made in this neglected group of lichens.New to Switzerland.This species was recently formally described and reported from Europe as well as North and South America (Westberg and Arup 2011).Compared to C. concolor (Dicks.)Stein, C. pacifica is characterized by an arachnoid appearance of the lower surface of the lobes due to the lack of a cortex (see also photographs in Bomble 2012).It also has 8-spored asci (polyspored in C. concolor) but it is rarely fertile in Europe.Candelaria pacifica is widespread in Europe and common at least in the northwestern parts, e.g., in the southern half of Scandinavia (Westberg and Arup 2010) but its frequency and ecology is not well known outside Scandinavia.In Switzerland it is apparently much less common than C. concolor and we have so far only seen a few specimens from Graubünden, Jura and Valais.Candelaria concolor on the other hand is common in Switzerland and also noticeably spreading, possibly due to nitrogen pollution.

Notes on the species
Specimens examined.Graubünden: Scuol, alt. 1990  Candelariella aggregata was recently reported from Europe for the first time from the Murmansk Region in Russia (Urbanavichus and Urbanavichene 2008) and also from Switzerland (Spinelli 2011).It is a terricolous species growing in arctic-alpine areas as well as in dry, steppe-like habitats in North America, Asia and Europe (Westberg 2007b, Westberg and Sohrabi manuscript).It is recognized by its yellow granular to areolate thallus, numerous and often crowded apothecia with a thin margin (Fig. 1).The asci are 8-spored with narrowly ellipsoid spores (14-)15-18(-21) × 5.0-6.0 µm.Compared to e.g., C. aurella (Hoffm.)Zahlbr it also has a proper exciple that does not form a distinct stipe below the hymenium and the structure of the exciple is paraplechtenchymatous with thin cell-walls (Westberg 2007b).Candelariella aggregata appears to be common in the continental parts of Switzerland in steppe-like habitats at low altitudes or on well lit calcareous walls on south-facing slopes at higher altitudes.
There is a large variation in thallus morphology, apothecia and in spore size in 8-spored terricolous material in Switzerland.Possibly several species are involved and this group is clearly in need of revision.The name C. unilocularis (Elenkin) Nimis has been used for a terricolous species with a well-developed thallus and long spores but this name is a synonym of C. aurella (Khodosovtsev 2005, Westberg and Sohrabi in press).Material of the long-spored species from the Swiss Alps will be described in a forthcoming paper (Otte and Westberg, in prep.).New to Switzerland and Austria.Candelariella antennaria is a corticolous or lignicolous species characterized by a grey thallus and 8-spored asci.The Swiss specimens were earlier identified as C. viae-lacteae.This species also has a grey thallus but it is uniformly composed of sphaerical granules, whereas the thallus in C. antennaria is contiguous or with scattered, convex areoles or indistinct but never distinctly granular (Fig. 2).Candelariella antennaria was first reported from Europe from Crete by Vondrak et al. (2008).There are several specimens from Switzerland, all from the continental valleys in Valais and Graubünden.In addition we have seen one specimen from Tirol in Austria.Candelariella antennaria probably has a circumpolar distribution in continental, dry regions but the name possibly represents a complex of species.
Specimens New to Switzerland.This newly described species is similar to C. xanthostigma (Ach.)Lettau but is easily identified by its sphaerical spores (ellipsoid in C. xanthostigma).Its distribution is little known and it has hitherto been reported from Greece, Slovakia and Spain (Etayo et al. 2009).All Swiss specimens were collected on deciduous trees in the lowest part of the montane belt between 700 and 1000 m.Only one specimen was collected in the framework of the Red List project and was identified as C. xanthostigma.The small granular, corticolous species is a difficult group in Candelariella.When sterile it is often not possible to identify the different species.The thallus in C. boleana is granular or becoming somewhat areolate with deeply incised areoles, up to c. 0.15 mm wide (Fig. 3).The Swiss specimens also showed aggregates of smaller granules (20-30 µm wide) here and there which could be interpreted as either groups of young granules or blastidiate soredia formed by disintegration of mature areoles.We do not know whether this is a characteristic feature of C. boleana.We can here confirm the presence of C. efflorescens (Fig. 4) in Switzerland by reporting six fertile specimens with c. 30-spored asci.They were collected mainly in the montane belt on deciduous and coniferous trees, mostly close to the ground.The three specimens collected in the framework of the Red List project were identified as C. xanthostigma.As most of the specimens of the small, sorediate Candelariella species are sterile, it is usually not possible to separate between C. New to Switzerland.This is a recently described arctic-alpine species reported from North America and northern Scandinavia (Westberg et al. 2011).This is possibly a circumpolar species and it is not surprising that it has now been found in Switzerland.The thallus is composed of small granules (Fig. 5) that soon disintegrate into blastidia (35-80 µm diam.) and the asci are polyspored.It is reminiscent of the corticolous species C. xanthostigma but the substrate and the disintegrating areoles separate it from this species.Of the other terricolous species Candelariella aggregata has 8-spored asci and C. vitellina has a much larger thallus of minute, effigurate areoles-subsquamules.The Swiss specimens were all collected in the continental parts of the country and were left unidentified until this study.New to Europe.This species is morphologically identical to C. efflorescens and can only be separated when fertile on account of its 8-spored asci compared to the c. 30-spored asci in C. efflorescens (Lendemer and Westberg 2010).The majority of the small, sorediate specimens in Candelariella are sterile and the distribution and frequency of the two species is thus poorly known.We found three fertile specimens with 8-spored asci which correspond well in all characters to C. xanthostigmoides.These specimens were mostly collected in humid places on Salix sp., Betula sp. and Alnus sp.The two specimens collected in the framework of the Red List project were identified as Candelariella reflexa (Nyl.)Lettau, another 8-spored, sorediate species.The latter species is however morphologically distinct also when sterile (see Lendemer and Westberg 2010).Earlier, the name C. sorediosa Poelt & Reddi had been used occasionally (e.g., Poelt and Vězda 1977) for similar specimens from Europe.We prefer to use the older name C. xanthostigmoides as the distinction between these two species is not clear and the type of C. sorediosa is poor (see also Lendemer and Westberg 2010).
species with a grey thallus.However, a recent find of C. viae-lacteae was made on mosses on a stem base of Fraxinus excelsior.Specimens examined.Solothurn: Messen, alt.500 m., 15 June 1998, Zimmermann (herb.E. Zimmerman).