"Sphagnum moss has a neutral pH as compared to the lower, more acidic pH (3.0 to 4.0) sphagnum peat moss. Peat moss is also high in tannins.
Water retention is excellent for both. Peat moss can retain up to 70% water.
Sphagnum moss has discernable plant parts, is very pliable, long-fibered, and has a soft spongy texture while the sphagnum peat moss is more decomposed with no recognizable plant parts, has short fibers, and finer texture."
https://www.plantssparkjoy.com/peat-moss-vs-sphagnum-moss/