Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2006 Jan 17;103(3):637-42.
doi: 10.1073/pnas.0510267103. Epub 2006 Jan 5.

Cryptic species within the cosmopolitan desiccation-tolerant moss Grimmia laevigata

Catherine C Fernandez  1 , James R Shevock, Alexander N Glazer, John N Thompson
Affiliations

Cryptic species within the cosmopolitan desiccation-tolerant moss Grimmia laevigata

Catherine C Fernandez et al. Proc Natl Acad Sci U S A. .

Abstract

The common cushion moss Grimmia laevigata (Bridel) Bridel grows on bare rock in a broad range of environments on every continent except Antarctica. As such, it must harbor adaptations to a remarkably broad set of environmental stresses, the extremes of which can include very high temperatures, prolonged nearly complete desiccation, and high ultraviolet B (UVB) exposure. Yet, like many mosses, G. laevigata shows very little morphological variability across its cosmopolitan range. This presents an evolutionary puzzle, the solution to which lies in understanding the phylogeographic structure of this morphologically simple organism. Here we report the results of an analysis of amplified fragment length polymorphisms (AFLPs) in G. laevigata, focusing on individuals from the California Floristic Province. We found evidence that populations within California constitute two distinct geographically overlapping cryptic species. Each clade harbors multiple private alleles, indicating they have been genetically isolated for some time. We suggest that the existence of cryptic species within G. laevigata, in combination with its life history, growth habits, and extreme desiccation tolerance, makes this moss an ideal research tool and a candidate for a biological indicator of climate change and pollution.

PubMed Disclaimer

Figures

Fig. 1.
Fig. 1.
Strict consensus cladogram showing maximum-parsimony relationships among the G. laevigata samples. P. gardneri and G. ovalis were used to root trees. Numbers above branches are boostrap values. Individuals are labeled with region and sample identification in parentheses, corresponding to Table 1.
Fig. 2.
Fig. 2.
Principal coordinates analysis of Jaccard's distance among the 46 Grimmia individuals. The first two axes explain 31.5% of total variation.
Fig. 3.
Fig. 3.
Map of collection sites of the 44 G. laevigata individuals.
Fig. 4.
Fig. 4.
Isolation-by-distance analysis among G. laevigata individuals. (a) All samples analyzed together. (b) Clade 1 analyzed separately. (c) Clade 2 analyzed separately. Each point shows Jaccard's index of genetic distance between a pair of individuals and the geographic distance between that pair.
See this image and copyright information in PMC

References

    1. Pócs, T. (1982) in Bryophyte Ecology, ed. Smith, A. J. E. (Chapman & Hall, London), pp. 59–104.
    1. Shevock, J. R. (2003) Fremontia 31, 12–20.
    1. Longton, R. E. (1988) The Biology of Polar Bryophytes and Lichens (Cambridge Univ. Press, Cambridge, U.K.).
    1. Proctor, M. C. F. & Pence, V. C. (2002) in Desiccation and Survival in Plants: Drying without Dying, eds. Black, M. & Pritchard, H. W. (CABI, Wallingford, U.K.), pp. 207–237.
    1. Liu, Y., Cao, T. & Glime, J. M. (2003) Bryologist 106, 53–60.

Publication types