Polish Botanical Journal 56(2): 315–319, 2011 FIRST RECORDS OF CANDELARIELLA EFFLORESCENS (LICHENIZED ASCOMYCOTA) IN POLAND DARIUSZ KUBIAK & MARTIN WESTBERG Abstract. Candelariella efflorescens R. C. Harris & W. R. Buck is reported as new for Poland. Its known localities, data on its ecology and total distribution, and a description of diagnostic features differentiating C. efflorescens from other similar species are given, with a map of its distribution in Poland based on revised herbarium specimens. Key words: lichens, Candelariella efflorescens, new records, distribution, ecology, Poland Dariusz Kubiak, Department of Mycology, Warmia and Mazury University in Olsztyn, Oczapowskiego 1A, 10-719, Olsztyn, Poland; e-mail:darkub@uwm.edu.pl Martin Westberg, Swedish Museum of Natural History, Cryptogamic Botany, P.O. Box 50007, S-104 05 Stockholm, Sweden; e-mail: martin.westberg@nrm.se INTRODUCTION The genus Candelariella (Candelariaceae, Asco- mycota) includes about fifty species worldwide (Westberg 2004), only eight of which are known in Poland (Fałtynowicz 2003). Many if not most species are still poorly known on a worldwide scale, and there probably are a large number of yet- undescribed species (Westberg et al. 2007). Within this large genus are five species recognized by the presence of soredia: C. medians (Nyl.) A. L. Sm., C. sorediosa Poelt & Reddi, C. xanthostigmoides (Müll. Arg.) R. W. Rogers, C. efflorescens R. C. Harris & W. R. Buck and C. reflexa (Nyl.) Lettau. Candelariella medians is a large placodioid spe- cies growing on calcareous rocks in Europe, and the others are small corticolous species. Of these, only C. efflorescens is characterized by having polysporous asci. Candelariella sorediosa was described by Poelt and Reddi (1969) from Nepal, but it is a poorly understood species and the name has been used rather infrequently in Asia (Aptroot & Sparrius 2003), Europe (Poelt & Vězda 1977) and South America (Sipman 1992). Candelariella xanthostigmoides was described from Australia (see Rogers 1982) and recently was reported and described in detail from North America (Lendemer & Westberg 2010). Candelariella efflorescens and C. reflexa both occur in Europe but only C. reflexa has been noted so far in Poland. This species has been known in Poland since the 1980s (Fałtynowicz 2003, see Nowak & Tobolewski 1975) but has been recorded infrequently (Fałtynowicz 2003; Kukwa 2005; Kubiak & Kukwa 2008). In 2010, richly fertile, sorediate specimens of Candelariella were found in northern Poland (Fig. 1). Morpho- logically the material resembles C. efflorescens, Fig. 1. Candelariella efflorescens R. C. Harris & W. R. Buck (D. Kubiak, OLTC L–2885). Scale bar = 1 mm.