The Collaborative International Dictionary of English v.0.48:

Malvastrum \Malvastrum\ n.
   A genus of mallows characterized by red and yellow flowers
   often placed in other genera.

   Syn: genus Malvastrum.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Malvastrum
    n 1: genus of mallows characterized by red and yellow flowers
         often placed in other genera [syn: Malvastrum, genus
         Malvastrum]