Garrett Crow 7367 Det. by: G. Crow, X 1989 Phenology: FR 15 October 1989 10:17N 85:20W 13 m GUANACASTE, NICOYA Valle del Tempisque. Abundant, forming large floating mats. Stems covered with thick layer of aerenchyma; petioles ascending, blades horizontal. Nodules on adventitions roots. Fruits abundant, many dehisced.
Garrett Crow 7407 Det. by: G. Crow, X 1989 Phenology: 20 October 1989 10:20N 85:20W 2 m GUANACASTE, BAGACES R.F.S. Dr. Rafael L. Rodrígu Valle del Tempisque. Abundant, plants much branched, stems surrounded by thick layer of aerenchymous tissue, leaves ascending.
Garrett Crow 7357 Det. by: G. Crow, X 1989 Phenology: FL 14 October 1989 10:57N 85:38W 300 m GUANACASTE, LA CRUZ De Bahía Salinas a Santa Cecilia. Abundant; plants floating on surface, stem covered with spongy aerenchyma, petioles ascending, blades horizontal. Flowers yellow, inflorescence globose, but stamens all unidirectional.
Garrett Crow 7636 Det. by: G. Crow, VIII 1990 Phenology: 27 August 1990 11:01N 85:32W 260 m GUANACASTE, LA CRUZ De Bahía Salinas a Santa Cecilia. Herbaceous, shrubby habit. Emergent.
Garrett Crow 7627 Det. by: G. Crow, VIII 1990 Phenology: FL 27 August 1990 11:01N 85:33W 260 m GUANACASTE, LA CRUZ De Bahía Salinas a Santa Cecilia. Herbaceous plant with shrubby habit. Emergent, ca. 1 m tall (stems not floating). Submersed stems lacking aerenchyma tissue. Flowers yellow, petals readily failing off.
Gerardo Herrera 3876 Det. by: B. Hammel, XI 1990 Phenology: 2 May 1990 11:02N 85:10W 30 m ALAJUELA, UPALA Llanura de Guatuso. Hierba acuática, flotante con hojas sensitivas; tallos huecos y sumamente esponjosos. Poco común.
Elba López 93 Det. by: Q. Jiménez, VI 1996 Phenology: LR 6 February 1996 11:02N 85:32W 270 m GUANACASTE, LA CRUZ P.N. Guanacaste De Bahía Salinas a Santa Cecilia. Planta, creciendo dentro de la Laguna. Inflorescencia amarilla. Frutos inmaduros verdes y maduros pardos.