KEYS TO THE LICHENS OF ITALY - 07) FRUTICOSE AND FOLIOSE TELOSCHISTACEAE
The taxonomy of Teloschistaceae is presently in a state of flux and high confusion, with different authors proposing different generic arrangements. In a recent revision of the Xanthorioideae, Kondratyuk et al. (2014) accepted no less than 31 genera for this group only (97 genera for the whole family). Here I follow the much less extreme splitting proposed by Arup & al. (2013).
Among the fruticose species, the genus Seirophora with c. 11 species, differs from Teloschistes s.str. in a number of characters, such as the lack of cilia or rhizines, the presence of multiseriate, complex hairs consisting of strongly conglutinated hyphae, and spores with a shorter septum. Teloschistes is widely distributed in the Southern Hemisphere, with diversity centres in Australia/New Zealand, South Africa and central South America. Only a few species occur outside these areas, and in the Northern Hemisphere only 3 species are present, which probably have spread from the Southern Hemisphere(Arup & al. 2013).
Among the foliose species, the traditional circumscription of Xanthoria has been profoundly modified, with the segregation of several species into other genera, such as Polycauliona, Rusavskia and Xanthomendoza (see Arup & al. 2013). In its narrower definition, Xanthoria is a well-supported genus of c. 10 species, including the slightly deviating X. resendei. The genus is best represented in the Northern Hemisphere, with an obvious diversity centre in the Mediterranean area. Polycauliona, as re-defined by Arup & al. (2013) is a rather large (c. 25 species) genus consisting of some smaller-sized foliose and fruticose species formerly included into Xanthoria, together with crustose species. Xanthomendoza was originally monotypic, until Søchting et al. (2002) transferred all Xanthoria-species with rhizines and bacilliform conidia to Xanthomendoza. Afterwards, the genus was once again made monotypic when all these species were transferred to Oxneria (Kondratyuk and Karnefelt 2003), a separation which was not generally accepted (see e.g. Lindblom 2006).
In spite of their showy appearance, Xanthorioid lichens are still rather poorly known in Europe, and especially in the Mediterranean region, with several species which would require further study. Here – pending molecular analysis of original material of Xanthomendoza huculica - I follow Lindblom et al. (2019) in treating X. huculica as a synonym of X. fallax. The key includes the 23 infrageneric taxa known to occur in Italy, plus Polycauliona ucrainica, which could occur in the country.
I am grateful to U. Arup (Lund), M. Grube and W. Obermayer (Graz), who provided material regarding Rusavskia hafellneri.
Arup U., Søchting U., Frödén P. 2013. A new taxonomy of the family Teloschistaceae. Nord. J. Bot., 31: 16-183.
Kondratyuk S., Kärnefelt I. 2003b. Revision of three natural groups of xanthorioid lichens (Teloschistaceae, Ascomycota). Ukrayins’kyi Bot. Zhurn. 60: 427–437.
Kondratyuk S.Y., Kärnefelt I., Thell A., Elix J.A., Kim J.A., Jeong M.H., Yu N.H., Hur J.S. 2014. A revised taxonomy of the subfamily Xanthorioideae (Teloschistaceae, Ascomycota) based on molecular phylogeny. Acta Bot. Hung., 56.
Lindblom L. 2006. Xanthomendoza galericulata, a new sorediate lichen species, with notes on similar species in North America. Bryologist, 190: 1-8.
Lindblom L., Blom, H.H., Timdal E. 2019. The genus Xanthomendoza in Norway. Graphis Scripta, 31(7): 54–75.
Sochting U. et al. 2002. Revision of Xanthomendoza (Teloschistaceae, Lecanorales) based on morphology, anatomy, secondary metabolites and molecular data. Mit. Inst. Allg. Bot. Hamburg 30-32: 225–240.
Last modified: July, 16, 2022