I'm working on a chart that keeps track of which animals are male / female and which ones are alive vs. frozen. I dunno if we'll need such a thing but it seemed more than coincidental that we know this for so many of them. Based on the text I've been able to come up with the following:

Known Animal Live / Crystal Unit
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Snail Mr. / Mrs. Ground
Dragonfly Mr. / Mrs. Air
Spider Mrs. / Mr. Ground
Beetle Mr. / Mrs. Ground
Caterpillar Mr. / Mrs. Ground
Hummingbird Mrs. / Mr. Air
Ladybug Mrs. / Mr. Air
Firefly Mr. / Mrs. Air
Bee Mr. / Mrs. Air

Unknown Animal Live / Crystal Unit
-------------------------------
Grasshopper Unk / Unk Air
Ant Unk / Unk Ground
Butterfly Unk / Unk Air