There are two forms of cf. U577, this is the green one. It is a trailing species from Thailand introduced in 2009, and is easy to grow, but prone to bronzing imperfections on the leaf. The leaves stay under 5″ and are defined by a broad silver green stripe that radiates out. Between this marking is are sections of dark green and maroon.
This pretty trailing species stays on the small side (with 4-5″ leaves) and is easy to grow. It was introduced in 2009 and is from Thailand. It forms a small rosette and then sends out runners, which can get quite long.