Pyxine Fr.
Type : Pyxine sorediata (Ach.) Fr. [=Lecidea sorediata Ach.]
Descriptions : Flora (1985: 493). See also Aptroot (1987: 41), Swinscow & Krog (1988: 262) and Kalb (2002: 437–438).
Key
Pyxine, included in the family Physciaceae nom. cons. (Eriksson et al. 2004; Pennycook & Galloway 2004; Eriksson 2005), comprises some 60 species found mainly in tropical regions (Malme 1897). Recent accounts dealing with Australian (Rogers 1986; Sammy 1988; Kalb 1994a), neotropical (Aptroot 1987), East African (Swinscow & Krog 1975a, 1975b, 1988; Moberg 1980), Sonoran Desert (Kalb 2002), palaeotropical (Kalb 2004a), and South African taxa (Moberg 2004b) contain much useful information. Pyxine is distinguished from other members of the Physciacea e by the lecideine apothecia; the K+ purple reaction of the epithecium; a dark-brown hypothecium; frequently lichexanthone (UV+ citrine yellow) in the upper cortex; and a black lower surface. Two species are present in New Zealand, both containing lichexanthone (UV+ yellow) and traces of triterpenoids.