I'm sure this a Mycena sp. but there are several similar ones, none of which are exactly the same.
Now this one looks like Podoserpula pusio. This one resembles Collybia eucalyptorum. Probably a Collybia sp. at least
This resembles Mycena epipterygia, however the stem doesn't appear as bright green as the photos of that species I can find.
I'm fairly sure this one is Pholiota malicola.
Hygrocybe graminicolor, details here.
This is possibly Mycena viscidocruenta. The tiny insect larvae (or something) crawling up the stem are interesting