Meta ovalis 
Metacyrba floridana 
Metacyrba taeniola 
Metallic jumper 
Metaphidippus albopilosus 
Metaphidippus chera 
Metellina merianae 
Mexican black velvet 
Mexican Orangeknee Tarantula 
Micrathena brevipes 
Micrathena decorata 
Micrathena kirbyi 
Micrathena kochalkai 
Micrathena miles 
Micrathena necopinata 
Micrathena sexspinosa 
Micrommata virescens 
Micropholcus fauroti 
Milky Flower Spider 
Mimic Cyrtarachne 
Missing Sector Orb Weaver 
Misumena spinifera 
Mouhot's Rolled-Leaf Spider 
Mountain huntsman