Ptychostomum imbricatulum

{{Short description|Species of moss}}

{{Speciesbox

| image = Bryum caespiticium.jpg

| taxon = Gemmabryum caespiticium

| authority = (Hedw.) J.R.Spence{{Cite WFO|genus=Gemmabryum |species=caespiticium |authority= (Hedw.) J.R. Spence |id=0001214645 |access-date=2024-04-07 }}

}}

Gemmabryum caespiticium, handbell moss,{{Cite GBIF|taxon=Gemmabryum caespiticium (Hedw.) J.R.Spence|ID=8099233}} is a species of moss belonging to the family Bryaceae.{{cite web |title=Bryum caespiticium Hedw. |url=http://www.worldfloraonline.org/taxon/wfo-0001156301 |website=www.worldfloraonline.org |access-date=1 February 2021}}

It has almost cosmopolitan distribution.

Gemmabryum caespiticium is known to be able to use artificial light to grow in places which are otherwise devoid of natural light, such as Crystal Cave in Wisconsin.{{cite journal |last1=Thatcher |first1=Edward P. |title=Bryophytes of an Artificially Illuminated Cave |journal=The Bryologist |date=1949 |volume=52 |issue=4 |pages=212-214 |doi=10.2307/3239480 }}