Expansion of the Stictidaceae by the addition of the saxicolous lichen-forming genus Ingvariella

Abstract

The monotypic, lichen-forming genus Ingvariella originally was segregated from Diploschistes and placed within the Thelotremataceae (Ostropales) based on aspects of exciple morphology. However, the I+ hymenium and amyloid ascus wall suggest affinities to families other than the Thelotremataceae. To assess the identity of Ingvariella and to investigate its placement within the Ostropales, we inferred phylogenetic relationships of I. bispora by comparison of mtSSU rDNA and nuLSU rDNA sequences for 59 species encompassing a broad array of ostropalean fungi by means of Bayesian, maximum likelihood and weighted maximum parsimony methods. Here we report that Ingvariella is a member of the Stictidaceae, sister to the mainly saprotrophic genus Cryptodiscus. The inclusion of the first saxicolous lichen-forming fungus within this family expands the broad ecological diversity of the Stictidaceae, where saprotrophic fungi, corticicolous lichen-forming fungi and lichenized and non-lichenized conspecific taxa have been described previously. We also present new insights into the relationships among other families within the Ostropales.

• Diploschistes
• exciple morphology
• Ingvariella
• molecular phylogenetics
• Ostropales
• Stictidaceae

The authors thank the curators of herbaria B, BCN, DUKE and MAF, in addition to Geir Hestmark, for providing material used in this study. Valérie Hofstetter also is thanked for generating some of the unpublished sequences in the AFTOL database used for this study; Frank Kauff and Jolanta Miadlikowska for help with the phylogenetic analyses; Esteve Llop, Pere Navarro, Mats Wedin and Andreas Frisch for useful comments on the results; Molly McMullen for the English revision and proofreading; and Néstor Hladun for help with image editing and for providing lab facilities. This study was supported by projects (CGL2007-66734-C03-02) and Filogènia molecular de les Teloschistales i Ostropales. II Part (IEC Secció Ciències Biològiques), a doctoral scholarship (FPU-Formación del Profesorado Universitario, Ministerio de Educación) to SFB, and the Assembling the Fungal Tree of Life (AFTOL) project, supported by NSF Assembling the Tree of Life (ATOL) award DEB-0228668 to FL.