The Collaborative International Dictionary of English v.0.48:

Chrysosplenium \Chrysosplenium\ n.
   a genus of widely distributed semiaquatic herbs with minute
   greenish-yellow apetalous flowers.

   Syn: genus Chrysosplenium.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Chrysosplenium
    n 1: genus of widely distributed semiaquatic herbs with minute
         greenish-yellow apetalous flowers [syn: Chrysosplenium,
         genus Chrysosplenium]