The only way that I can even have a chance at a ROUGH ID is to know where the moss is growing at: name of State and the type of area it is in: that is, in full sun on a rock, under an oak tree in partial shade, or ????
But even that information may not be enough. Normally I need a sample to exam with magnification to try and get ID to species, if possible.
Mosses can be easily grown but I cannot make any recommendations until I know more about it. Once I do then I can help you in growing it in a pot.

Very lovely image!
I hope we find out more!

Josh

"The only way that I can even have a chance at a ROUGH ID is to know where the moss is growing at: name of State and the type of area it is in: that is, in full sun on a rock, under an oak tree in partial shade, or ????
But even that information may not be enough. Normally I need a sample to exam with magnification to try and get ID to species, if possible."

Ok, I don't think I could send a sample, it would die by the time it got to your area, i think. It resided on Guam, on a tree trunk. It took up a large part, probably a foot long, or a foot and a half. The area was heavily shaded, lots of trees. It is very humid and warm where I live.

Though any effort to save it might be futile... my dad chopped down the tree!

I'm sorry, it's probably more like 2 feet. Here is a picture from further away, if it will help just a bit.

Even if I can't get an exact ID, do you have any general suggestions i could try for transplanting (if I find this moss again--i see it very often)?

{{gwi:609014}}

Mosses that grow on the bark of trees can be very fussy about the surface on which they grow. Many do not transplant well. It might be possible to transplant a small amount to another tree or a log and under the right light and moisture it could take hold. Another possibility is scatter some spores onto a new substrate and if conditions are favorable it should establish.

OK. In Guam.
This is a moss that can be saved.
But do you want to spend time caring for it or do you want to just have it growing in nature. \
If as in nature then I would get a large pot and set one end of the branch into the pot and fill in with very coarse gravel or small rocks that will keep the brnach upright. Sit it in a setting that reminds you of where you found it. I am presuming rainfall and weather conditions will be similar. If not you may want to supplement the water but use only distilled, rain, or r/o water.
If you want to experiment with growing it then I would shave off a portion of the branch with the moss attached and set it into a plastic vegetable box that you can find at a grocer (??) Like this one:
{{gwi:609016}}
Spray the moss sample with distilled/rain or r/o water and close lid. Set in shade.
Do you want to propagate the moss?
Because this is an epiphytic moss it is going to be one tough plant. Probably tougher than the local Bryum that grows in the cracks of sidewalks here. These mosses get completely dried out but they come back to life during the winter rains. I am currently experimenting with cultivating this moss.
On identifying the moss you may want to check with the university of Guam. Check the link below.

Here is a link that might be useful: University of Guam Micronescia

Yo! Think I have got this moss down to genus. This is really a guess but it sure looks like the one in the image at the link below.
a species of Macromitrium

Here is a link that might be useful: Macromitrium

I'm in such awe of how much people know about plants on these forums! I guess I'm really a newbie.

Thanks for the help. I definitely will try this soon hopefully. Is that felt at the bottom of that container? (Was it just in there already?)

I just realized getting an ID won't do much for me yet, lol. I don't know what to do with the name now. I guess I was really looking more for practical info. :)

...even though knowledge of the plant would be practical in the long run. :D

Yeah, Terrestrial Man is the Man! ;)
Thanks for the follow-ups.

Josh

Thanks Josh. Just call me lucky! though I do work at it!!
But yes that is felt at the bottom of the vegetable box.
I am using that bin to propagate the Bryum species. What I am using is artificial felt not wool felt. Get it soaked in r/o, distillied, or rain water.
Then I took the Bryum that I scrapped up from a crack in my driveway when it was bone dry. Then I ground it up in my hands and sprinkled the moss dust over the wet felt.
Closed the cover and sat in a northern shady spot. It is working!! The different pieces of the moss are growing new moss plants.
I think you could do the same Maria with the moss you have. Just be patient and give it time to grow. I spray the closed container when I spray my other mosses which can be every two hours in warm weather, but with high humidity you may not need to do so. Just do not let the felt dry out.
To help you learn more about your moss here is a link that has some ecological info that may be of interest.

Here is a link that might be useful: Macromitrium in Australia

awesome. i will try that, and will try to read up what's pertinent soon.

one more question occurred to me... is there a way to transplant it to grow on a rock...?

Cannot really say. The only epiphytic mosses I have grow on bark and I have not tried to propagate them, even onto bark. But I would think that you need the same kind of rock that you find the moss growing on. If you can you may be able to include rocks into the felt system and get them all wet along with the felt and then spread the moss dust over all of them. In this case you would only use the finest setting on your sprayer to create a fog mist that would not, hopefully, wash the moss pieces off the rocks.
If I ever get any moss species that grow on rocks (not over rocks) I definitely will want to try.