This is a tiny spider, about 4 mm body length.
Phintella vittata are the first and only animals capable of seeing ultraviolet B light (several insects, birds, fish, and mammals can see only ultraviolet A light). Males of these jumping spider species have patches on their abdomens that reflect UVB light which can be detected by the females. Experts say that there may be other animals that can detect UVB light.

Tub Kaek Beach area, Krabi, Thailand, 3 February 2013