Ephemera are things that exist or are used or enjoyed for only a brief while. Ephemera also describes items of collectible memorabilia, usually written or printed, that were not meant to be permanent.
Day lily blooms are ephemeral -- each bloom lasts only a day -- hence the name.
The other night I discovered a bit of ephemera in a book I was re-reading for the umpteenth time -- a magazine blow-in, pressed into duty as a book mark -- after being used for some preliminary planning for a baby quilt made, many years ago, by our community of friends. (Each person was supposed to choose what animal they would like to embroider.)
The ephemeral nature of this creased bit pf paper was underlined for me by the fact that two of the women I'd listed have passed on.
"Man that is born of a woman is of few days and full of trouble.
He cometh forth like a flower and is cut down. . ."
It's all so fleeting -- one day, one night, one span of years. We have to pay attention lest we miss something.