Help me ID this species

Description:

Found a bunch of these in our front yard, It has rained this morning and yesterday. Never have seen these guys before! Im sure its a flatworm but unsure of what type nor do I think it is native. It also left alim behind like that of a snail. Looks like a mix between a slug and an earthworm. They are very small about an inch! Please let me know if you know what it is.

Habitat:

Yard

Notes:

We live in southern california, anaheim