Mycological Progress

, Volume 8, Issue 1, pp 9–18 | Cite as

Acaulosporoid glomeromycotan spores with a germination shield from the 400-million-year-old Rhynie chert

  • Nora Dotzler
  • Christopher Walker
  • Michael KringsEmail author
  • Hagen Hass
  • Hans Kerp
  • Thomas N. Taylor
  • Reinhard Agerer
Original Article


Scutellosporites devonicus from the Early Devonian Rhynie chert is the only fossil glomeromycotan spore taxon known to produce a germination shield. This paper describes a second type of glomeromycotan spore with a germination shield from the Rhynie chert. In contrast to S. devonicus, however, these spores are acaulosporoid and develop laterally in the neck of the sporiferous saccule. Germination shield morphology varies, from plate-like with single or double lobes to tongue-shaped structures usually with infolded margins that are distally fringed or palmate. Spore walls are complex and appear to be constructed of at least three wall groups, the outermost of which includes the remains of the saccule. The complement of features displayed by the fossils suggests a relationship with the extant genera Ambispora, Otospora, Acaulospora or Archaeospora, but which of these is the closest extant relative cannot be determined. The acaulosporoid spores from the Rhynie chert document that this spore type was in existence already ∼400 mya, and thus contribute to a more complete understanding of the evolutionary history of the Glomeromycota. This discovery pushes back the evolutionary origin of all main glomeromycotan groups, revealing that they had evolved before rooted land plants had emerged.


Fossil fungi Glomeromycota Pragian-?earliest Emsian (Early Devonian) Spore-saccule complex Spore wall 



This study was supported in part by funds from the National Science Foundation (EAR-0542170 to T.N.T. and M.K.), the Deutsche Forschungsgemeinschaft (Ke 584/13–1 to H.K.), and the Alexander von Humboldt-Foundation (V-3.FLF-DEU/1064359 to M.K.). We acknowledge with thanks the loan of the holotype of Otospora bareai by the curator of the Mycological Herbarium of the ETH Zurich (ZT).


  1. Ames RN, Linderman RG (1976) Acaulospora trappei sp. nov. Mycotaxon 3:565–569Google Scholar
  2. Berch SM (1985) Acaulospora sporocarpia, a new, sporocarpic species, and emendation of the genus Acaulospora (Endogonaceae, Zygomycotina). Mycotaxon 23:409–418Google Scholar
  3. De Souza FA, Declerck S, Smit E, Kowalchuk GA (2005) Morphological, ontogenetic and molecular characterization of Scutellospora reticulata (Glomeromycota). Mycol Res 109:697–706 doi: 10.1017/S0953756205002546 PubMedCrossRefGoogle Scholar
  4. Dotzler N, Krings M, Taylor TN, Agerer R (2006) Germination shields in Scutellospora (Glomeromycota: Diversisporales, Gigasporaceae) from the 400 million-year-old Rhynie chert. Mycol Prog 5:178–184 doi: 10.1007/s11557-006-0511-z CrossRefGoogle Scholar
  5. Franke M, Morton JB (1994) Ontogenetic comparisons of arbuscular mycorrhizal fungi Scutellospora heterogama and Scutellospora pellucida: Revision of taxonomic character concepts, species descriptions, and phylogenetic hypotheses. Can J Bot 72:122–134 doi: 10.1139/b94-017 CrossRefGoogle Scholar
  6. Gerdemann JW, Trappe JM (1974) The Endogonaceae in the Pacific Northwest. Mycol Mem 5:1–76Google Scholar
  7. Hafeel KM (2004) Spore ontogeny of the arbuscular mycorrhizal fungus Archaeospora trappei (Ames & Linderman) Morton & Redecker (Archaeosporaceae). Mycorrhiza 14:213–219 doi: 10.1007/s00572-004-0300-y PubMedCrossRefGoogle Scholar
  8. Hass H, Rowe NP (1999) Thin sections and wafering. In: Jones TP, Rowe NP (eds) Fossil plants and spores: modern techniques. Geological Society, London, pp 76–81Google Scholar
  9. Helgason T, Fitter A (2005) The ecology and evolution of the arbuscular mycorrhizal fungi. Mycologist 19:96–101 doi: 10.1017/S0269915X05003022 CrossRefGoogle Scholar
  10. INVAM (International Culture Collection of (Vesicular) Arbuscular Mycorrhizal Fungi) [last accessed July 17, 2008]
  11. Koske RE, Gemma JN (1995) Scutellospora hawaiiensis: A new species of arbuscular mycorrhizal fungus from Hawaii. Mycologia 87:678–683 doi: 10.2307/3760811 CrossRefGoogle Scholar
  12. Koske RE, Walker C (1986) Species of Scutellospora (Endogonaceae) with smooth-walled spores from maritime sand dunes: two new species and redescription of the spores of Scutellospora pellucida and Scutellospora calospora. Mycotaxon 27:219–235Google Scholar
  13. Kramadibrata K, Walker C, Schwarzott D, Schüßler A (2000) A new species of Scutellospora with a coiled germination shield. Ann Bot (Lond) 86:21–27 doi: 10.1006/anbo.2000.1146 CrossRefGoogle Scholar
  14. Krings M, Taylor TN, Hass H, Kerp H, Dotzler N, Hermsen EJ (2007) An alternative mode of early land plant colonization by putative endomycorrhizal fungi. Plant Signal Behav 2:125–126PubMedGoogle Scholar
  15. Morton JB (1988) Taxonomy of VA mycorrhizal fungi: classification, nomenclature and identification. Mycotaxon 32:267–324Google Scholar
  16. Morton JB, Benny GL (1990) Revised classification of arbuscular mycorrhizal fungi (Zygomycetes): a new order, Glomales, two new suborders, Glomineae and Gigasporineae, and two new families, Acaulosporaceae and Gigasporaceae, with an emendation of Glomaceae. Mycotaxon 37:471–491Google Scholar
  17. Morton JB, Redecker D (2001) Two new families of Glomales, Archaeosporaceae and Paraglomaceae, with two new genera Archaeospora and Paraglomus, based on concordant molecular and morphological characters. Mycologia 93:181–195 doi: 10.2307/3761615 CrossRefGoogle Scholar
  18. Muthukumar T, Damodaran PN, Rajeshkannan V, Udaiyan K (2005) Distribution, spore ontogeny and host reactions in Acaulospora scrobiculata (Diversisporales). Nova Hedw 81:477–491 doi: 10.1127/0029-5035/2005/0081-0477 CrossRefGoogle Scholar
  19. Oehl F, Sieverding E (2004) Pacispora, a new vesicular arbuscular fungal genus in the Glomeromycetes. J Appl Bot 78:72–82Google Scholar
  20. Palenzuela J, Ferrol N, Boller T, Azcón-Aguilar C, Oehl F (2008) Otospora bareai, a new fungal species in the Glomeromycetes from a dolomitic shrubland in the Natural Park of Sierra de Baza (Granada, Spain). Mycologia 100:296–305 doi: 10.3852/mycologia.100.2.296 PubMedCrossRefGoogle Scholar
  21. Redecker D, Raab P (2006) Phylogeny of the Glomeromycota (arbuscular mycorrhizal fungi): recent developments and new gene markers. Mycologia 98:885–895 doi: 10.3852/mycologia.98.6.885 PubMedCrossRefGoogle Scholar
  22. Remy W, Taylor TN, Hass H, Kerp H (1994) Four hundred-million-year-old vesicular arbuscular mycorrhizae. Proc Natl Acad Sci USA 91:11841–11843 doi: 10.1073/pnas.91.25.11841 PubMedCrossRefGoogle Scholar
  23. Rice CM, Trewin NH, Anderson LI (2002) Geological setting of the Early Devonian Rhynie cherts, Aberdeenshire, Scotland: an early terrestrial hot spring system. J Geol Soc Lond 159:203–214 doi: 10.1144/0016–764900–181 CrossRefGoogle Scholar
  24. Schüßler A, Mollenhauer D, Schnepf E, Kluge M (1994) Geosiphon pyriforme, an endosymbiotic association of fungus and cyanobacteria: the spore structure resembles that of arbuscular mycorrhizal (AM) fungi. Bot Acta 107:36–45Google Scholar
  25. Schüßler A, Schwarzott D, Walker C (2001) A new fungal phylum, the Glomeromycota: phylogeny and evolution. Mycol Res 105:1413–1421 doi: 10.1017/S0953756201005196 CrossRefGoogle Scholar
  26. Sieverding E, Oehl F (2006) Revision of Entrophospora and description of Kuklospora and Intraspora, two new genera in the arbuscular mycorrhizal Glomeromycetes. J Appl Bot Food Qual 80:69–81Google Scholar
  27. Spain JL (1992) Patency of shields in water mounted spores of four species in Acaulosporaceae (Glomales). Mycotaxon 28:331–339Google Scholar
  28. Spain JL (2003) Emendation of Archaeospora and of its type species, Archaeospora trappei. Mycotaxon 87:109–112Google Scholar
  29. Spain JL, Sieverding E, Toro S (1989) Scutellospora biornata: A new species in the Endogonaceae from the Llanos orientales of Colombia. Mycotaxon 35:219–227Google Scholar
  30. Spain JL, Sieverding E, Oehl F (2006) Appendicispora: a new genus in the arbuscular mycorrhiza-forming Glomeromycetes, with a discussion of the genus Archaeospora. Mycotaxon 97:163–182Google Scholar
  31. Stürmer S, Morton J (1999) Taxonomic reinterpretation of morphological characters in Acaulosporaceae based on developmental patterns. Mycologia 91:849–857 doi: 10.2307/3761538 CrossRefGoogle Scholar
  32. Taylor TN, Remy W, Hass H, Kerp H (1995) Fossil arbuscular mycorrhizae from the Early Devonian. Mycologia 87:560–573 doi: 10.2307/3760776 CrossRefGoogle Scholar
  33. Taylor TN, Klavins SD, Krings M, Taylor EL, Kerp H, Hass H (2004) Fungi from the Rhynie chert: a view from the dark side. Trans R Soc Edinb Earth Sci 94:457–473Google Scholar
  34. Taylor TN, Hass H, Kerp H (2005) Life history biology of early land plants: deciphering the gametophyte phase. Proc Natl Acad Sci USA 102:5892–5897 doi: 10.1073/pnas.0501985102 PubMedCrossRefGoogle Scholar
  35. Trewin NH, Rice CM (eds) (2004) The Rhynie hot springs system: geology, biota and mineralisation (Transactions of the Royal Society of Edinburgh, Earth Sciences 94). The Royal Society of Edinburgh Scotland Foundation, EdinburghGoogle Scholar
  36. Walker C (1983) Taxonomic concepts in the Endogonaceae: spore wall characteristics in species descriptions. Mycotaxon 18:443–455Google Scholar
  37. Walker C, Sanders FE (1986) Taxonomic concepts in the Endogonaceae: III. The separation of Scutellospora gen. nov. from Gigaspora Gerd. & Trappe. Mycotaxon 27:169–182Google Scholar
  38. Walker C, Vestberg M (1998) Synonymy amongst the arbuscular mycorrhizal fungi: Glomus claroideum, G. maculosum, G. multisubstensum and G. fistulosum. Ann Bot (Lond) 82:601–624 doi: 10.1006/anbo.1998.0714 CrossRefGoogle Scholar
  39. Walker C, Reed LE, Sanders FE (1984) Acaulospora nicolsonii, a new endogonaceous species from Great Britain. Trans Br Mycol Soc 83:360–364CrossRefGoogle Scholar
  40. Walker C, Cuenca G, Sanchez F (1998) Scutellospora spinosissima sp. nov., a newly described glomalean fungus from acidic, low nutrient plant communities in Venezuela. Ann Bot (Lond) 82:721–725 doi: 10.1006/anbo.1998.0728 CrossRefGoogle Scholar
  41. Walker C, Błaszkowski J, Schwarzott D, Schuessler A (2004) Gerdemannia gen. nov., a genus separated from Glomus, and Gerdemanniaceae fam. nov., a new family in the Glomeromycota. Mycol Res 108:707–718 doi: 10.1017/S0953756204000346 PubMedCrossRefGoogle Scholar
  42. Walker C, Vestberg M, Demircik F, Stockinger H, Saito M, Sawaki H, Nishmura I, Schüßler A (2007) Molecular phylogeny and new taxa in the Archaeosporales (Glomeromycota): Ambispora fennica gen. sp. nov., Ambisporaceae fam. nov., and emendation of Archaeospora and Archaeosporaceae. Mycol Res 111:137–153 doi: 10.1016/j.mycres.2006.11.008 PubMedCrossRefGoogle Scholar
  43. Wellman CH (2006) Spore assemblages from the Lower Devonian ‘Lower Old Red Sandstone’ deposits of the Rhynie outlier, Scotland. Trans R Soc Edinb Earth Sci 97:167–211 doi: 10.1017/S0263593300001449 Google Scholar
  44. Wellman CH, Kerp H, Hass H (2006) Spores of the Rhynie chert plant Aglaophyton (Rhynia) major (Kidston and Lang) D.S. Edwards, 1986. Rev Palaeobot Palynol 142:229–250 doi: 10.1016/j.revpalbo.2006.04.009 CrossRefGoogle Scholar

Copyright information

© German Mycological Society and Springer 2008

Authors and Affiliations

  • Nora Dotzler
    • 1
    • 2
  • Christopher Walker
    • 3
  • Michael Krings
    • 1
    • 4
    Email author
  • Hagen Hass
    • 5
  • Hans Kerp
    • 5
  • Thomas N. Taylor
    • 4
  • Reinhard Agerer
    • 2
  1. 1.Bayerische Staatssammlung für Paläontologie und Geologie und GeoBio-CenterLMULudwig-Maximilians-Universität MünchenMunichGermany
  2. 2.Department Biologie I und GeoBio-CenterLMU, Organismische Biologie: MykologieLudwig-Maximilians-Universität MünchenMunichGermany
  3. 3.Royal Botanic Garden EdinburghEdinburghUK
  4. 4.Department of Ecology and Evolutionary Biology, and Natural History Museum and Biodiversity Research CenterThe University of KansasLawrenceUSA
  5. 5.Forschungsstelle für Paläobotanik am Geologisch-Paläontologischen InstitutWestfälische Wilhelms-Universität MünsterMünsterGermany

Personalised recommendations