This is Plexippus paykuli (Audouin, 1826), also known as the pantropical jumping spider. It is often found on old logs where it matches its body type, blends into cracks or holes, and prefers to ambush a long march of ants. It has a fat abdomen, bright pedipalps, and shorter front legs; this indicates it's a female. These photos were taken in my yard this afternoon. Many spiders like that hang around my yard all the time. Sometimes I wait for them to ambush a swarm of ants; I do my work as they hunt.
