Approximately meter-deep supports emergent herbaceous perennials, typically in dense, monospecific stands; species include bulrush (Typha latifolia), pickerelweed (Pontederia cordata), American lotus (Nelumbo lutea).
A 2011 analysis by Amy Driskell and colleagues of mitochondrial and nuclear DNA found the Broad-billed Fairywren and Campbell's Fairywren to lie in a clade with the two other monospecific New Guinea genera and not with the other species of Malurus.
Nuytsia (genus), the monospecific genus containing the species Nuytsia floribunda, the Western Australian Christmas Tree;
Poranthera alpina has been placed in the monospecific genus Oreoporanthera by some authors, but in 2007, a molecular phylogenetic analysis of matK and ITS sequences showed this species to be embedded in Poranthera.
In Kaneohe Bay it is the dominant coral species and sometimes forms monospecific stands.
The African Dwarf Kingfisher is sometimes placed in the monospecific genus Myioceyx, and sometimes with the Pygmy Kingfishers in Ispidina.
In 1987, Peters named another monospecific genus of ameghinornithid, Aenigmavis sapea, based on a nearly complete skeleton from the Middle Eocene Messel pit of Germany.