Projektin Peat Mosses (Sphagnum) of the SE US Päiväkirja

@palustrisbotany asked me about resources for identifying Sphagnum in Texas. I haven't collected Sphagnum in Texas, but I tried to figure out how I'd start going about it and found some interesting stuff.

First, not surprisingly, only east Texas has Sphagnum. As of this writing, 9 species were reported on iNaturalist (current map at https://www.inaturalist.org/observations?place_id=18&subview=map&taxon_id=54704). A 1980 compilation (Lodwick and Snyder 1980) lists 10, and the Texas Bryology website (https://www.texasbryology.com/peatmosses-sphagnum-in-texas) names 11 species. All of these correspond pretty well to the list of commonly collected species in bryophyteportal.org. Not only is this list manageably short, but even better, most of the species on it have a fairly distinct field appearance, so with the help of microscope slides, most should be identifiable.

If I get time I'll add notes on each of the most likely-seen species, but in the meantime, if you're in Texas and intrigued, you can't do better for an introduction than the lovely piece by Bob Klips, "Getting Started with Sphagnum," which both shows you what you'd be getting into and makes it all seem worthwhile (https://ohiomosslichen.org/getting-started-with-sphagnum/).

REFERENCES

Klips, Bob, [accessed 3 March 2023], Getting Started with Sphagnum, https://ohiomosslichen.org/getting-started-with-sphagnum/.

Lodwick, L. N. & J. A. Snyder .1980. The Distribution of Sphagnum Taxa in Texas. The Bryologist 83:214 -218 (https://www.jstor.org/stable/3242136). This tells which species have been reported in which counties and describes habitats for each species.

Peat Mosses (Sphagnum) in Texas, https://www.texasbryology.com/peatmosses-sphagnum-in-texas

I just completed a very nice online seminar on Sphagnum with Jonathan Shaw (given through Eagle Hill Institute, https://www.eaglehill.us/programs/sems-online/flyers-online-pdfs/2023-Shaw.pdf). He presented a lot of the newer phylogenetic work on Sphagnum that he and others have done, and I used the information to make some notes that would update the 2009 book. I paste them in here (you are going to have to imagine the scientific names italicized because I'm not going to do all that formatting):

Updates to Anderson, Shaw & Shaw 2009 as of Feb 2023

p. 22. Sphagnum magellanicum. MOLECULAR/MORPHOLOGICAL REVISION: Gulf Coast specimens now seen as S. magniae; Appalachian specimens are S. diabolicum (Shaw et al. 2022; Shaw et al. 2023).

p. 30 .Sphagnum henryense not distinct from S. palustre: MOLECULAR CONFIRMATION: confirmed not distinct (Karlin et al. 2010). JS says this still needs more work, though.

p. 45 & 49 & 52. Sphagnum capillifolium, S. rubellum, S. subtile, and S. tenerum. MOLECULAR REVISION: S. rubellum, S. tenerum and S. capillifolium are distinct entities; S. subtile is not distinct from S. capillifolium (Shaw et al. 2005, and Karn Imwattana’s work).

p. 51. Sphagnum bartlettianum. MOLECULAR CONFIRMATION: S. bartlettianum confirmed not distinct from S. rubellum (Shaw et al. 2005, and Karn Imwattana’s work).

p. 69-70. Sphagnum cuspidatum complex (S. cuspidatum, S. trinitense, S. mississipiense, S. fitzgeraldii). MOLECULAR REVISION: S. trinitense and S. mississipiense sort out from S. cuspidatum with nuclear DNA. They are also more or less identifiable morphologically; in particular, branch leaves on the proximal part of the branch are serrate in S. trinitense and inrolled and non-serrate in S. cuspidatum (with Robinson, in prep).

p. 74. Sphagnum atlanticum: MOLECULAR CONFIRMATION: Sphagnum atlanticum confirmed not genetically distinct from S. torreyanum (Shaw et al. 2009).
p. 78. “Sphagnum recurvum complex” (S. recurvum, S. angustifolium, S. fallax, and S. flexuosum): MOLECULAR DETAILS: S. recurvum, S. angustifolium, S. fallax all genetically distinct; S. flexuosum very close to S. recurvum (morphologically, S. fallax has pointy stem leaves, and the others, especially S. angustifolium, have rounded stem leaves) (Duffy et al. 2020).
p. 89. Sphagnum microcarpum: “more work is needed to confirm that S. microcarpum is distinct from S. cyclophyllum.” No revision yet on this.

Higher classification: Anderson, Shaw & Shaw 2009 is organized into sections of Sphagnum including Sections Squarrosus and Isocladus, but now these are viewed more in terms of Subgenus clades, in which Squarrosa is part of Subg. Acutifolia and Isocladus is within Subg. Subsecunda.

REFERENCES

Anderson, L. E., A. J. Shaw and B. Shaw. 2009. Peat mosses of the southeastern United States. Memoirs of the New York Botanical Garden, vol. 102. New York Botanical Garden Press.
Duffy, A. M., Aguero, B., Stenøien, H. K., Flatberg, K. I., Ignatov, M. S., Hassel, K., & Shaw, A. J. (2020). Phylogenetic structure in the Sphagnum recurvum complex (Bryophyta) in relation to taxonomy and geography. American Journal of Botany, 107(9), 1283-1295. https://doi.org/10.1002/ajb2.1525
Karlin, E. F., Giusti, M. M., Lake, R. A., Boles, S. B., & Shaw, A. J. (2010). Microsatellite analysis of Sphagnum centrale, S. henryense, and S. palustre (Sphagnaceae). The Bryologist, 113(1), 90-98, https://doi.org/10.1639/0007-2745-113.1.90.

Shaw, J., Cox, C. J., & Boles, S. B. (2004). Phylogenetic relationships among Sphagnum sections: hemitheca, isocladus, and subsecunda. The bryologist, 107(2), 189-196. https://doi.org/10.1639/0007-2745(2004)107[0189:PRASSH]2.0.CO;2

Shaw, A. J., Cox, C. J., & Boles, S. B. (2005). Phylogeny, species delimitation, and recombination in Sphagnum section Acutifolia. Systematic Botany, 30(1), 16-33, https://doi.org/10.1600/0363644053661823.

Shaw, A. J., Nieto-Lugilde, M., Aguero, B., Duffy, A., Piatkowski, B. T., Jaramillo-Chico, J., ... & Hicks, K. A. (2023). Sphagnum diabolicum sp. nov. and S. magniae sp. nov.; morphological variation and taxonomy of the “S. magellanicum complex”. The Bryologist, 126(1), 69-89. https://doi.org/10.1639/0007-2745-126.1.069.

Shaw, A. J., Piatkowski, B., Duffy, A. M., Aguero, B., Imwattana, K., Nieto‐Lugilde, M., ... & Hicks, K. A. (2022). Phylogenomic structure and speciation in an emerging model: the Sphagnum magellanicum complex (Bryophyta). New Phytologist, 236(4), 1497-1511. https://doi.org/10.1111/nph.18429.

Shaw, B., Terracciano, S., & Shaw, A. J. (2009). A genetic analysis of two recently described peat moss species, Sphagnum atlanticum and S. bergianum (Sphagnaceae). Systematic Botany, 34(1), 6-12. https://doi.org/10.1600/036364409787602212.

Here's a very preliminary draft guide to the most common Sphagnum species in south Mississippi and nearby:

https://www.inaturalist.org/journal/janetwright/62676-common-sphagnum-peatmosses-of-south-mississippi