Searching GenBank for PoSet (Population sets) in your organism is a help. 

http://www.ncbi.nlm.nih.gov/popset?LinkName=taxonomy_popset&from_uid=50937

Poke around there, read a few of the papers that were published about those data sets.

A multigene phylogenetic synthesis for the class Lecanoromycetes (Ascomycota): 1307 fungi representing 1139 infrageneric taxa, 317 genera and 66 families.  Miadlikowska J, Kauff F, Högnabba F, Oliver JC, Molnár K, Fraker E, Gaya E, Hafellner J, Hofstetter V, Gueidan C, Otálora MA, Hodkinson B, Kukwa M, Lücking R, Björk C, Sipman HJ, Burgaz AR, Thell A, Passo A, Myllys L, Goward T, Fernández-Brime S, Hestmark G, Lendemer J, Lumbsch HT, Schmull M, Schoch CL, Sérusiaux E, Maddison DR, Arnold AE, Lutzoni F, Stenroos S.  Mol Phylogenet Evol. 2014 Oct;79:132-68. doi: 10.1016/j.ympev.2014.04.003. Epub 2014 Apr 18.

PMID:  24747130

Dissociation and horizontal transmission of codispersing lichen symbionts in the genusLepraria (Lecanorales: Stereocaulaceae).

Nelsen,M.P. and Gargas,A.  (2008) New Phytol. 177:(1)264-275

New insights into classification and evolution of the Lecanoromycetes (Pezizomycotina, Ascomycota) from phylogenetic analyses of three ribosomal RNA- and two protein-coding genes.

Miadlikowska,J., Kauff,F., Hofstetter,V., Fraker,E., Grube,M., Hafellner,J., Reeb,V., Hodkinson,B.P., Kukwa,M., Lucking,R., Hestmark,G., Otalora,M.G., Rauhut,A., Budel,B., Scheidegger,C., Timdal,E., Stenroos,S., Brodo,I., Perlmutter,G.B., Ertz,D., Diederich,P., Lendemer,J.C., May,P., Schoch,C.L., Arnold,A.E., Gueidan,C., Tripp,E., Yahr,R., Robertson,C. and Lutzoni,F.  (2006) Mycologia 98:(6)1088-1103

PMID:

17486983