A new species of non-lichenized genus <I>Stictis</I> (<I>Ostropales</I>, <I>Lecanoromycetes</I>) from India

Abstract

Abstract — Stictis subbrachyspora is described as new species from India. The new species is characterized by a non-lichenized habit; round, effigurate, chroodiscoid apothecia with white pruinose, lacerate margins, and transversely 19–32 loculate small ascospores measuring 45–55 × 4–5 µm. Stictis himalayanus is published as a new combination based on Chroodiscus himalayanus.Key words — Stictidaceae, corticolous, Ascomycota, Conotrema Introduction The family Stictidaceae (Ostropales, Lecanoromycetes, Ascomycota) accommodates a large group of lichenized and non-lichenized fungi. The species of the genus Stictis Pers. are perhaps the best known example of individuals representing the same fungal species having the ability to live either in a lichenized state (with algal symbionts) or as saprotrophs (non-lichenized), depending on the substrate (Wedin et al. 2004).Sherwood (1977a,b, 1979) provided a comprehensive account of c. 65 species and separated Stictis from allied genera based on the orbicular fruiting body opening by pores, periphysoids in an apothecial margin that extends down the whole length, a hymenium that splits away from the margin when dry, a thick crystalline layer in the ascoma margin and a non-parasitic niche. The ascospores exhibit variation in shape (cylindrical or filiform), size, and septation (with 3–300 septa). Stictis was segregated from the closely related Conotrema based on the lichenized living strategy and scattered crystals in apothecial margin of the latter (Gilenstam 1969, Sherwood 1977a). A phylogenetic account by Wedin et al. (2006) suggests that Stictis is paraphyletic and congeneric with