Multilocus approach to species recognition in the Cladonia humilis complex (Cladoniaceae, Ascomycota)

American Journal of Botany

Volumn 100, Issue 4, 2013, Pages 664-678

  Pino Bodas, Raquel ^a   Ahti, Teuvo ^b   Stenroos, Soili ^b   Martín, María P ^c   Burgaz, Ana R ^a  

^a UNIVERSIDAD COMPLUTENSE DE MADRID   (Spain)

^b UNIVERSITY OF HELSINKI   (Finland)

^c CSIC   (Spain)

Author keywords

Ascomycota; Cladonia; Cladoniaceae; ef1 ; Genealogical sorting index; Lichen; rpb2; Species delimitation

Indexed keywords

CONSPECIFIC; GENEALOGY; LICHEN; MORPHOLOGY; PHYLOGENETICS; SECONDARY METABOLITE;

ARTICLE; ASCOMYCETES; CLASSIFICATION; FUNGAL GENE; GENETICS; PHENOTYPE; PHYLOGENY;

ASCOMYCOTA; GENES, FUNGAL; PHENOTYPE; PHYLOGENY;

EUROPE;

ASCOMYCOTA; CLADONIA; CLADONIA HUMILIS; CLADONIA KUROKAWAE; CLADONIA PULVINELLA; CLADONIA SUBCONISTEA; CLADONIACEAE;

EID: 84875719848     PISSN: 00029122     EISSN: None     Source Type: Journal    
DOI: 10.3732/ajb.1200162     Document Type: Article

References (104)

1. AHTI, T. 1966. Correlation of the chemical and morphological characters in Cladonia chlorophaea and allied lichens. Annales Botanici Fennici 3: 380-389.
2. AHTI, T. 1980. Taxonomic revision of C ladonia gracilis and its allies. Annales Botanici Fennici 17: 195-243.
3. AHTI, T. 1993. Names in current use in the Cladoniaceae (lichen-forming ascomycetes) in the ranks of genus to variety. Regnum Vegetabile 128: 58-106.
4. AHTI, T. 1998. A revision of Cladonia stricta. Folia Cryptogamica Estonica 32: 5-8.
5. AHTI, T. 2000. Cladoniaceae. Flora Neotropica Monograph 78: 1-362.
6. AHTI, T., AND S. HAMMER. 2002. Cladonia. In T. H. Nash III, B. D. Ryan, C. Gries, and F. Bungartz [eds.], Lichen fl ora of the Greater Sonoran Desert Region, vol. 1, 131-158. Arizona State University, Tempe, Arizona, USA.
7. AHTI, T., AND S. HYVÖNEN. 1985. Cladina stygia, a common, overlooked species of reindeer lichen. Annales Botanici Fennici 22: 223-229.
8. AHTI, T., S. STENROOS, J. B. CHEN, AND S. Y. GUO. 1995. The status of C. humilis in East Asia. Mycosystema 8: 53-58.
9. APTROOT, A., J. M. SIPMAN, AND C. M. VAN HERK. 2001. Cladonia monomorpha, a neglected cup lichen from Europe. Lichenologist 33: 271-283.
10. ARCHER, A. W. 1989. Two new lichens: Cladonia paeminosa and C. humilis var. bourgeanica. Muelleria 7: 1-5.
11. ARGÜELLO, A., R. DEL PRADO, P. CUBAS, AND A. CRESPO. 2007. Parmelia quercina (Parmeliaceae, Lecanorales) includes four phylogenetically supported morphospecies. Botanical Journal of the Linnean Society 91: 455-467.
12. AWASTHI, D., AND T. AHTI. 2007. Cladonia. In D. Awasthi [ed.], A compendium of the macrolichens from India, Nepal and Sri Lanka, 79-116. Bishen Singh Mahedra Pal Singh, Dehra Dun, India.
13. BURGAZ, A. R., AND T. AHTI. 1998. Contribution to the study of the genera Cladina and Cladonia in Spain. III. Nova Hedwigia 66: 549-555.
14. BURGAZ, A. R., AND T. AHTI. 2009. Cladoniaceae. Flora Liquenológica Ibérica 4: 1-111.
15. BUSCHBOM, J., AND G. M. MUELLER. 2006. Testing "species pair" hypotheses: Evolutionary processes in the lichen-forming species complex Porpidia fl avocoerulescens and Porpidia melinodes. Molecular Biology and Evolution 23: 574-586.
16. CARSTENS, B. C., AND T. A. DEWEY. 2010. Species delimitation using a combined coalescent and information-theoretic approach: An example from North American Myotis bats. Systematic Biology 59: 400-414.
17. CARSTENS, B. C., AND L. L. KNOWLES. 2007. Estimating species phylogeny from gene-tree probabilities despite incomplete lineage sorting: An example from Melanoplus grasshoppers. Systematic Biology 56: 400-411.
18. CHEN, W.-J., M. MIYA, K. SAITOH, AND R. L. MAYDEN. 2008. Phylogenetic utility of two existing and four novel nuclear gene loci in reconstructing Tree of Life of rayfi nned fi shes: The order Cypriniformes (Ostariophysi) as a case study. Gene 423: 125-134.
19. CLEMENT, M., D. POSADAS, AND A. K. CRANDALL. 2000. TCS: A computer program to estimate genealogies. Molecular Ecology 9: 1657-1660.
20. CUMMINGS, M. P., M. C. NEEL, AND K. L. SHAW. 2008. A genealogical approach to quantifying lineage divergence. Evolution 62: 2411-2422.
21. DEL-PRADO, R., P. CUBAS, H. T. LUMBSCH, P. K. DIVAKAR, O. BLANCO, G. AMO DE PAZ, M. C. MOLINA, AND A. CRESPO. 2010. Genetic distances within and among species in monophyletic lineages of Parmeliaceae (Ascomycota) as a tool for taxon delimitation. Molecular Phylogenetics and Evolution 56: 125-133.
22. DOLNIK, C., A. BECK, AND D. ZARABSKA. 2010. Distinction of Cladonia rei and C. subulata based on molecular, chemical and morphological characteristics. Lichenologist 42: 373-386.
23. FONTAINE, K. M., T. AHTI, AND M. D. PIERCEY-NORMORE. 2010. Convergent evolution in Cladonia gracilis and allies. Lichenologist 42: 323-338
24. GARDES, M., AND T. D. BRUNS. 1993. ITS primers with enhanced specifi city for Basidiomycetes-Application to the identifi cation of mycorrhiza and rust. Molecular Ecology 2: 113-118.
25. GAZIS, R., S. REHNER, AND P. CHAVERRI. 2011. Species delimitation in fungal endophyte diversity studies and its implications in ecological and biogeographic inferences. Molecular Ecology 20: 3001-3013.
26. GOFFINET, B., J. MIADLIKOWSKA, AND T. GOWARD. 2003. Phylogenetic inferences based on nrDNA sequences support fi ve morphospecies within the Peltigera didactyla complex (Lichenized Ascomycota). Bryologist 106: 349-369.
27. GÖKER, M., G. GARCÍA-BLÁZQUEZ, H. VOGLMAYR, M. T. TELLERÍA, AND M. P. MARTÍN. 2010. Molecular taxonomy of phytopathogenic fungi: A case study in Peronospora. PLoS ONE 4: e6319.
28. GÖKER, M., H. V OGLMAYR, G. G ARCÍA-BLÁZQUEZ, AND F. OBERWINKLER. 2009. Species delimitation in downy mildews: The case of Hyaloperonospora in the light of nuclear ribosomal ITS and LSU sequences. Mycological Research 113: 308-325.
29. GROENEVELD, L. F., D. W. WEISROCK, R. M. RASOLOARISON, A. D. YODER, AND P. M. KAPPELER. 2009. Species delimitation in lemurs: Multiple genetics loci reveal low levels of species diversity in the genus Cheirofaleus. BMC Evolutionary Biology 9: 30.
30. GURUSHIDZE, M., R. M. FRITSCH, AND F. R. BLATTNER. 2010. Specieslevel phylogeny of Allium subgenus Melanocrommyum: Incomplete lineage sorting, hybridization and trnF gene duplication. Taxon 53: 829-840.
31. HAMMER, S. 1991. A preliminary synopsis of the species of Cladonia in California and adjacent Oregon. Mycotaxon 40: 169-197.
32. HAMMER, S. 1995. A synopsis of the genus Cladonia in the northwestern United States. Bryologist 98: 1-28.
33. HAMMER, S. 2001. Additions to the lichen family Cladoniaceae in Australia. Bryologist 104: 560-575.
34. HAMMER, S., AND T. AHTI. 1990. New and interesting species of Cladonia from California. Mycotaxon 37: 335-348.
35. HECKMAN, K. L., C. L. MARIANI, R. RASOLOARISON, AND A. D. YODER. 2007. Multiple nuclear loci reveal patterns of incomplete lineage sorting and complex species history within western mouse lemurs (Microcebus). Molecular Phylogenetics and Evolution 43: 353-367.
36. HENNINGS, C. J. 1983. The Cladonia chlorophaea-C. fi mbriata complex in western Washington. Bryologist 86: 64-73.
37. HODKINSON, B. P., AND J. C. L ENDEMER. 2011. Molecular analyses reveal semi-cryptic in Xanthoparmelia tasmanica. Bibliotheca Lichenologica 106: 115-126.
38. HOLIEN, H., AND T. TØNSBERG. 1985. Notes on Cladonia asahinae, C. conista and the C. grayi group in Norway. Gunneria 51: 1-26.
39. HUELSENBECK, J., AND F. RONQUIST. 2001. MRBAYES: Bayesian inference of phylogenetic trees. Bioinformatics 17: 754-755.
40. HUOVINEN, K., T. AHTI, AND S. STENROOS. 1989. The composition and contents of aromatic lichen substances in Cladonia, section Cocciferae. Annales Botanici Fennici 26: 133-148.
41. HUOVINEN, K., T. AHTI, AND S. STENROOS. 1990. The composition and contents of aromatic lichen substances in Cladonia section Cladonia and group Furcatae. Bibliotheca Lichenologica 38: 209-241.
42. JAMES, P. W. 2009. Cladonia. In C. W. Smith, A. Aptroot, B. J. Coppins, A. Fletcher, O. L. Gilbert, P. W. James, and P. A. Wolseley [eds.], The lichens of Great Britain and Ireland, 309-338. Natural History Museum Publications, London, UK.
43. JØLLE, O. H. 1977. New lichen to Norway and Sweden: Cladonia cyathomorpha. Blyttia 35: 163-166.
44. KOTELKO, R., AND M. D. PIERCEY-NORMORE. 2010. Cladonia pyxidata and C. pocillum: Genetic evidence to regard them as conspecifi c. Mycologia 102: 534-545.
45. KRISTINSSON, H. 1971. Morphological and chemical correlations in the Cladonia chlorophaea complex. Bryologist 74: 13-17.
46. LAGRECA, S. 1999. A phylogenetic evaluation of the Ramalina americana chemotype complex (lichenized Ascomycota, Ramalinaceae) based on rDNA ITS sequence data. Bryologist 102: 602-618.
47. LARSSON, K.-H., E. LARSSON, AND U. KÕLJALG. 2004. High phylogenetic diversity among corticioid homobasidiomycetes. Mycological Research 108: 983-1002.
48. LENDEMER, J. C. 2012. Perspectives on chemotaxonomy: Molecular data confi rm the existence of two morphologically distinct species within a chemically defi ned Lepraria caesiella (Stereocaulaceae). Castanea 77: 89-105.
49. LENDEMER, J. C., AND B. P. HODKINSON. 2009. The wisdom of fools: New molecular and morphological insights into the North American apodetiate species of Cladonia. Opuscula Philolichenum 7: 79-100.
50. LIBRADO, P., AND J. ROZAS. 2009. DnaSP v5: A software for comprehensive analysis of DNA polymorphism data. Bioinformatics 25: 1451-1452.
51. LINDBLOM, L., AND S. EKMAN. 2005. Molecular evidence supports the distinction between Xanthoria parietina and X. aureola (Teloschistales, lichenized Ascomycota). Mycological Research 109: 187-199.
52. LIU, Y. J., S. WHELEN, AND B. D. HALL. 1999. Phylogenetic relationships among Ascomycetes: Evidence from an RNA polymerase II subunit. Molecular Biology and Evolution 16: 1799-1808.
53. LÜCKING, R., R. DEL-PRADO, H. T. LUMBSCH, S. WILL-WOLF, A. APTROOT, H. J. M. SIPMAN, L. UMANA, AND J. L. CHAVES. 2008. Phylogenetic patterns of morphological and chemical characters and reproductive mode in the Heterodermia obscurata group in Costa Rica (Ascomycota, Physciaceae). Systematics and Biodiversity 6: 31-41.
54. LUMBSCH, H. T., AND S. D. LEAVITT. 2011. Goodbye morphology? A paradigm shift in the delimitation of species in lichenized fungi. Fungal Diversity 50: 59-70.
55. LUMBSCH, H. T., A. M ANGOLD, M. P. MARTÍN, AND J. A. ELIX. 2008a. Species recognition and phylogeny of Thelotrema species in Australia (Ostropales, Ascomycota). Australian Systematic Botany 21: 217-227.
56. LUMBSCH, H. T., M. P. NELSEN, AND R. LÜCKING. 2008b. The phylogenetic position of Heamatommataceae (Lecanorales, Ascomycota), with notes on secondary chemistry and species delimitation. Nova Hedwigia 86: 105-114.
57. LUTZONI, F., F. K AUFF, C. J. C OX, D. MCLAUGHLIN, G. C ELIO, B. DENTINGER, M. PADAMSEE, ET AL. 2004. Assembling the fungal tree of life: Progress, classifi cation, and evolution of subcellular traits. American Journal of Botany 91: 1446-1480.
58. LUTZONI, F., P. WAGNER, V. REEB, AND S. ZOLLER. 2000. Integrating ambiguously aligned regions of DNA sequences in phylogenetic analyses without violating positional homology. Systematic Biology 49: 628-651.
59. MEUDT, H. M., P. J. LOCKHART, AND D. BRYANT. 2009. Species delimitation and phylogeny of a New Zealand plant species radiation. BCM Evolution Biology 9: 111.
60. MOLINA, M. C., P. K. DIVAKAR, A. M. M ILLANES, E. SÁNCHEZ, R. D ELPRADO, D. L. HAWKSWORTH, AND A. CRESPO. 2011. Parmelia sulcata (Ascomycota: Parmeliaceae), a sympatric monophyletic species complex. Lichenologist 43: 585-601.
61. MORANDO, M., L. AVILA, J. BAKER, AND J. W. SITES. 2004. Phylogeny and phylogeography of the Liolaemus darwinii complex (Squamata: Liolaemidae): Evidence for introgression and incomplete lineage sorting. Evolution 58: 842-861.
62. MYLLYS, L., S. STENROOS, A. THELL, AND T. AHTI. 2003. Phylogeny of bipolar Cladonia arbuscula and Cladonia mitis (Lecanorales, Euascomycetes). Molecular Phylogenetics and Evolution 27: 58-69.
63. NELSEN, M. P., AND A. GARGAS. 2009. Assessing clonality and chemotype monophyly in Thamnolia (Icmadophilaceae). The Bryologist 112: 42-53.
64. NYLANDER, J. A. A. 2004. MrModeltest v2. Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden. Computer program distributed by the author, available from http://www.abc.se/~nylander/.
65. NYLANDER, J. A. A., J. C. WILGENBUSCH, D. L. WARREN, AND D. L. SWOFFORD. 2008. AWTY (Are we there yet?): A system for graphical exploration of MCMC convergence in Bayesian phylogenetics. Bioinformatics 24: 581-583.
66. PAGÈS, M., Y. CHAVAL, V. HERBRETEAU, S. WAENGSOTHORN, J. F. COSSON, J. P. HUGOT, S. MORAND, AND J. MICHAUX. 2010. Revisiting the taxonomy of the Rattini tribe: A phylogeny-base delimitation of species boundaries. BMC Evolutionary Biology 10: 184.
67. PAUS, S., F. J. A. DANIELS, AND H. T. LUMBSCH. 1993. Chemical and ecological studies in the Cladonia subulata complex in northern Germany (Cladoniaceae, lichenised Ascomycotina). Bibliotheca Lichenologica 53: 191-200.
68. PÉREZ-VARGAS, I. 2008. Los líquenes del Parque Nacional de La Caldera de Taburiente (La Palma, Islas Canarias). Ph.D. dissertation, Universidad de La Laguna, Tenerife, Spain.
69. PIERCEY-NORMORE, M. D., T. AHTI, AND T. GOWARD. 2010. Phylogenetic and haplotype analyses of four segregates within Cladonia arbuscula s.l. Botany 88: 397-408.
70. PIERCEY-NORMORE, M. D., AND P. T. DEPRIEST. 2001. Algal switching among lichen symbioses. American Journal of Botany 88: 1490-1498.
71. PINO-BODAS, R., T. AHTI, S. STENROOS, M. P. MARTÍN, AND A. R. BURGAZ. 2012a. Cladonia conista and C. humilis (Cladoniaceae) are different species. Bibliotheca Lichenologica 108: 161-178.
72. PINO-BODAS, R., A. R. BURGAZ, AND M. P. MARTÍN. 2010a. Elucidating the taxonomic rank of Cladonia subulata versus C. rei (Cladoniaceae). Mycotaxon 113: 311-326.
73. PINO-BODAS, R., A. R. BURGAZ, M. P. MARTÍN, AND T. H. LUMBSCH. 2012b. Species delimitations in the Cladonia cariosa group (Cladoniaceae, Ascomycota). Lichenologist (London, England) 44: 121-135.
74. PINO-BODAS, R., M. P. M ARTÍN, AND A. R. B URGAZ. 2010b. Insight into the Cladonia convoluta-C. foliacea (Cladoniaceae, Ascomycota) complex and related species, revealed through morphological, biochemical and phylogenetic analyses. Systematics and Biodiversity 8: 575-586.
75. PINO-BODAS, R., M. P. MARTÍN, AND A. R. BURGAZ. 2012c. Cladonia subturgida and C. iberica (Cladoniaceae) form a single, morphologically and chemically polymorphic species. Mycological Progress 11: 269-278.
76. PORTER, A. H. 1990. Testing nominal species boundaries using gene fl ow statistics-The taxonomy of two hybridizing admiral butterfl ies (Limenitis, Nymphalidae). Systematic Zoology 39: 131-147.
77. PRINTZEN, C., E. EKMAN, AND T. TØNSBERG. 2003. Phylogeography of Cavernularia hultenii: Evidence of slow genetic drift in a widely disjuntion lichen. Molecular Ecology 12: 1473-1486.
78. RAMBAUT, A. 2002. Se-Al v2.0a11: Sequence alignment editor. Available from http://evolve.zoo.ox.ac.uk/.
79. ROSENBERG, N. A. 2003. The shapes of neutral gene genealogies in two species: Probabilities of monophyly, paraphyly, and polyphyly in a coalescent model. Evolution 57: 1465-1477.
80. SAKALIDIS, M. L., G. E. HARDY, AND T. I. BURGESS. 2011. Use of the genealogical sorting index (GSI) to delimitate species boundaries in the Neofusiococcum parvum-Neofusiococcum ribis species complex. Molecular Phylogenetics and Evolution 60: 333-344.
81. SCHMIDT, H. A., K. STRIMMER, M. VINGRON, AND A. VON HAESELER. 2002. TREE-PUZZLE: Maximum likelihood phylogenetic analysis using quartets and parallel computing. Bioinformatics 18: 502-504.
82. SCHOCH, C., K. A. SEIFERT, S. HUHNDORF, V. ROBERT, J. L. SPOUGE, A. LEVESQUE, W. CHEN, AND FUNGAL BARCODING CONSORTIUM. 2012. Nuclear ribosomal internal transcribed spacer (ITS) region as a universal DNA barcode marker for Fungi. Proceedings of the National Academy of Sciences, USA 109: 6241-6246.
83. SHAFFER, H. B., AND R. C. THOMSON. 2007. Delimiting species in recent radiations. Systematic Biology 56: 896-906.
84. SHIMODAIRA, H., AND M. HASEGAWA. 1999. Multiple comparisons of loglikelihoods with applications to phylogenetic inference. Molecular Biology and Evolution 16: 1114-1116.
85. SICILIA, D., C. HERNÁNDEZ-PADRÓN, AND A. R. BURGAZ. 2009. The genus Cladonia in Garajonay National Park, La Gomera, Canary Islands. Cryptogamie. Mycologie 30: 305-316.
86. ŠOUN, J., J. VONDRÁK, U. SØCHTING, P. H ROUZEK, A. KHODOSOVTSEV, AND U. ARUP. 2011. Taxonomy and phylogeny of the Caloplaca cerina group in Europe. Lichenologist (London, England) 43: 113-135.
87. SPRIBILLE, T., B. KLUG, AND H. MAYRHOFER. 2011. A phylogenetic analysis of the boreal lichen Mycoblastus sanguinarius (Mycoblastaceae, lichenized Ascomycota) reveals cryptic clades correlated with fatty acid profi les. Molecular Phylogenetics and Evolution 59: 603-614.
88. STAMATAKIS, A. 2006. RAxML-VI-HPC: Maximum-likelihood-based phylogenetic 1118 analyses with thousands of taxa and mixed models. Bioinformatics 22: 2688-2690.
89. STENROOS, S. 1995. Cladoniaceae (Lecanorales, Lichenized Ascomycota) in Chile. Gayana Botánica 52: 89-131.
90. STENROOS, S., J. HYVÖNEN, L. MYLLYS, A. THELL, AND T. AHTI. 2002. Phylogeny of the genus Cladonia s. lat. (Cladoniaceae, Ascomycetes) inferred from molecular, morphological and chemical data. Cladistics 18: 237-278.
91. STRIMMER, K., AND A. RAMBAUT. 2002. Inferring confi dence sets of possibly misspecifi ed gene trees. Proceedings of the Royal Society, B, Biological Sciences 269: 137-142.
92. SWOFFORD, D. L. 2003. PAUP*: Phylogenetic analysis using parsimony (*and other methods), version 4.0b10. Sinauer, Sunderland, Massachusetts, USA.
93. TAKAHASHI, K., Y. TERAI, M. NISHIDA, AND N. OKADA. 2001. Phylogenetic relationships and ancient incomplete lineage sorting among cichlid fi shes in Lake Tanganyika as revealed by analysis of the insertion of retroposons. Molecular Biology and Evolution 18: 2057-2066.
94. TAYLOR, J. W., D. J. JACOBSON, S. KROKEN, T. KASUGA, D. M. GEISER, D. S. HIBBETT, AND M. C. FISHER. 2000. Phylogenetic species recognition and species concepts in fungi. Fungal Genetics and Biology 31: 21-32.
95. VAN HERK, C. M., AND A. APTROOT. 2003. A new status for the western European taxa of the Cladonia cervicornis group. Bibliotheca Lichenologica 86: 193-203.
96. VAINIO, E. A. 1887. Monographia Cladoniarum universalis I. Acta Societatis pro Fauna et Flora Fennica 4: 1-509.
97. VONDRÁK, J., P. Ř ÍHA, U. A RUP, AND U. S ØCHTING. 2009. The taxonomy of the Caloplaca citrina group (Teloschistaceae) in the Black Sea region; with contributions to the cryptic species concept in lichenology. Lichenologist 41: 571-604.
98. WEDIN, M., M. WESTBERG, A. T. CREWE, A. TEHLER, AND O. W. PURVIS. 2009. Species delimitation and evolution of metal bioaccumulation in the lichenized Acarospora smaragdula (Ascomycota, Fungi) complex. Cladistics 25: 161-172.
99. WEIR, B. S., AND C. C. COCKERHAM. 1984. Estimating F-statistics for the analysis of population structure. Evolution 38: 1358-1370.
100. WHITE, F. J., AND P. W. JAMES. 1985. A new guide to microchemical techniques for the identifi cation of lichen substances. British Lichen Society Bulletin 75 (supplement): 1-41.
101. WHITE, T. J., T. BRUNS, S. LEE, AND J. W. TAYLOR. 1990. Amplifi cation and direct sequencing of fungal ribosomal RNA genes for phylogenetics. In M. A. Innis, D. H. Gelfand, J. J. Sninsky and T. J. White [eds.], PCR protocols: A guide to methods and applications, 315-322. Academic Press, San Diego, California, USA.
102. WILLYARD, A., R. CRONN, AND A. LISTON. 2009. Reticulate evolution and incomplete lineage sorting among the ponderosa pines. Molecular Phylogenetics and Evolution 52: 498-511.
103. WIRTZ, N., C. PRINTZEN, AND H. T. LUMBSCH. 2008. The delimitation of Antarctic and bipolar species of neuropogonoid Usnea (Ascomycota, Lecanorales): A cohesion approach of species recognition for Usnea perpusilla complex. Mycological Research 112: 472-484.
104. YAHR, R., R. VILGALYS, AND P. T. DEPRIEST. 2006. Geographic variation in algal partners of Cladonia subtenuis (Cladoniaceae) highlights the dynamic nature of a lichen symbiosis. New Phytologist 171: 847-860.