Section Tetraspermium is widespread, owing to two species, namely A. scandens  (Aublet) Engl. and A. trinerve Miq., but a number of mostly Andean species remain undescribed. Most species range from very dry areas, such as Tropical Dry Forest (A. pohlii Engl.) to Tropical Moist Forest, but a few species, such as A. scandens ssp. pusillum Sheffer and A. lacinosum Sodiro, ranges into Premontane Wet Forest and Premontane Rain Forest.

Another small but widespread section is Dactylophyllium , a group with palmately compound blades. It ranges throughout most of the range of the genus (except in Paraguay and Argentina) and is most abundant in regions of Tropical Moist Forest. The section is most diverse in eastern South America and in the Amazon basin. It is represented by such species as A. eminens Schott, A. pentaphyllum (Aublet) Don and A. clavigerum Poeppig. A few species from eastern South America may be new to science.

A well known but insignificant group is Leptanthurium . It is represented by A. gracile  (Rudge) Schott, one of the most widespread species in the genus. This is the only Anthurium species with a chromosome base number of 10 and is believed to be unrelated to any described and the section is not closely related to any other section. A few additional undescribed Andean species probably also belong here, but their chromosomes have not yet been studied.

Two monotypic sections are very geographically isolated. Section Chamaerepium with a single species, A. radicans Koch & Haage occurs in eastern Brazil while A. gymnopus Griseb. is endemic to Cuba. Neither group appears to have any close relatives.

A large number of Anthurium species remain unclassified as to section. Species involved mostly consist of larger cordate-leaved species which clearly do not belong in any of the other described cordate groups, e. g., Cardiolonchium , Calomystrium , Polyneurium , or Belolonchium . Probably several small sections will have to be created to accommodate them. Engler placed most of such species known to him in section Belolonchium . Another somewhat smaller group which does not fit into any recognized section includes more or less oblong to lanceolate-leaved plants lacking glandular punctations, e. g., A. michelii Guillaumin. Both groups contain new species.

Future work on Anthurium must concentrate in two areas:the Andean countries, especially Colombia, Ecuador and Peru as well as in eastern Brazil. The problems in these two areas are very different. In eastern Brazil the majority of thespecies have been described but are still poorly defined and little understood. They are very similar to one another, and the type localities are very much degraded. Some species may be lost all together.

In the Andes of western South America species diversity is much higher, and there are many undescribed or poorly known species. A great deal of time and space will be needed just to sort out the specimens to determine how many species there are.

LITERATURE CITED

Baker, R. A. & W. C. Burger. 1976. Key and commentary on the species of Spathiphyllum (Araceae) in Costa Rica, including S. silvicola, sp. nov. Phytologia 33(7): 447-453.