I only know the videogame lemmings (vague memory) and I love how they used umbrella's when falling down. So I love lemmings, even more now I saw that picture. Go lemmings!
On some versions of Star Trek's planet Vulcan, there is a dangerous tiger-like creature called a lematya (sometimes le-matya), of which the prophet Surak wrote the following parable:
Pretending there is not a lematya in your bed will not make it go away if there is one. You must first admit to yourself the fact that there is a lematya — you must first accept its presence. Then you can call the animal control people and have them come and take it away. But until you first admit that it is there, you are going to have a lematya in your bed every night. It may save your pride not to admit that it is there, but your bed will be increasingly crowded.
I do not recommend the name "lematya" for most Lemmy users, but we'll need to keep in mind that sometimes there is a lematya among the lemurs.
(The quote is from Diane Duane's novel Spock's World.)
So that's four options right there. I'd go for "lemurs", in part because it's an old Usenet meme, and Usenet is an early federated discussion-board service. Frink!
For Unix novices & others: The line beginning with $ grep up there is a Unix command line, suitable for use on a Linux system. It uses the grep search utility to scan a standard English word list using a regular expression. The expression ^lem\w*s$ means "any line of text, containing one word, that starts with 'lem' and ends in an 's'.")
("Lemons" would be funny too, but even more so for people who've seen the ABC/Marvel series Agents of S.H.I.E.L.D. ...)