Belonia uncinata (Gyalectales, Ascomycotina) New to South America

Abstract

Belonia uncinata P. M. McCarthy & Kantvilas, described from Tasmania, is reported as new to southern Argentina, where it occurs in Nothofagus dombeyi forests. The species is characterized by its unusually uncinate, filiform, and transversally septate ascospores. The genus Belonia Nyl. is characterized by a crustose or pulverulent thallus that is thin or immersed within the substratum. The photobiont belongs to the genera Trentepohlia or Trebouxia. The ascomata are apothecia, but resemble perithecia. The hamathecium is composed of paraphyses, and lateral paraphyses are lacking. The hymenium usually stains more or less blue in iodine. The asci are unitunicate, thin-walled without an apical apparatus, and the ascospores are colorless, needle-shaped or fusiform, transversally septate or rarely muriform (Navarro-Rosin6s & Llimona 1997). The genus includes about 12 species worldwide (Hawksworth et al. 1983). Six species were reported from Europe (Jergensen et al. 1983; NavarroRosin6s & Llimona 1997; V~zda 1959) and three species occur in SE Australia (McCarthy, pers. comm.), while the genus is poorly known in South America. The genus has not previously been reported from Argentina (Grassi 1952). In connection with a survey on the lichen flora of the Nothofagus forests in southwestern Argentina, we found material of B. uncinata, a species that was previously known only from Tasmania. The species is briefly discussed and a description based on the Argentinian material is given.