Mosses ar a remarkable adaptable ancient plant species we actually still know very little about... They can be remarkably resistant as they can be remarkably sensitive to minute changes in their environment. A sudden small change can make them go dormant and looking dead and stay like that till it improves again in their favour to revive again. Or they simply might change morphologically and revive in a completely different grow form.
A few years ago I took home some moss I thought it was some kind of Star moss, from the local forest, far away from water growing on sandy soil. Did put it submerged in a tank, all went brown looking dead and ugly. I just left it like that for months. And all of a sudden it revived grew new shoots from its tips looking rather different.
There are quite some more mosses that can grow both ways on land as in your garden and in water and both forms look different but it's the same moss. One known aquatic moss in the trade is called stringy moss - Leptodictyum Riparium.
Land form
Aquatic form
We only know a few, likely there are many more... Maybe all mosses if given the proper conditions can do this.
The question is what is this condiction? The other question is, what moss are we talking about? Determining this beyond the few we know can be extremely difficult and few people are able to do this accurately in 90% of the cases its guesswork.
Thus Rock & Roll, you never know!...