Marsilea crenata Presl is growing in the demonstration taro ponds of Hawai'i Nature Center, Makiki Valley, Honolulu, O'ahu. The presence of this vounteer population was first recorded in the journal of the Nature Center by Marie Bruegmann on 18 May 1994. The first known collection made at this site is that of Dan Palmer on 1 June 1995 (2275, BISH). Marsilea crenata is native to southeastern Asia (Philippines, Malaysia, Indonesia, Australia) where it grows in shallow fresh water and in drying mud. It is often found in rice paddies. The plants are rooted in the mud and the leaflets float on the water surface or the erect petioles extend above the surface of the water and hold the leaflets well above the surface. When fertile, one or two sporocarps are formed at the base of the petiole. Reports of the presence of M. crenata in Nu'uanu Valley are unconfirmed.
