Children (6 direct children, 6 direct and indirect children):
Ceratophyllum submersum var. haynaldianum
Ceratophyllum submersum var. echinatum
Ceratophyllum submersum subsp. muricatum
Ceratophyllum submersum var. squamosum
Ceratophyllum submersum subsp. submersum
Ceratophyllum submersum var. submersum