margin giving the cut-away view a cochleate appearance); plants usually lacking a "bird's-nest" habit; leaves various.

11.

Stems scandent, wiry (usually less than 3 mm thick), with numerous short, adventitious roots scattered along their length; internodes elongate, flowering branches bearing 1-6 leaves; 1-ribbed cataphylis lacking, Mexico to Panama
section Polyphyllium Engl.

Stems short or scandent but not slender and wiry; internodes short or long but usually more than 8 mm long, the adventitious roots restricted to the nodes; flowering branches bearing a single leaf (branches are short and do not appear to be branches); 1-ribbed cataphylis present and usually conspicuous.

11.

12.

Roots white, bearing velamen; blades thin, narrowly oblanceolate, the primary lateral veins numerous and scarcely more prominent than the interprimary veins; stems rarely more than 1 cm diam. with persistent, reddish-brown, intact cataphylls; spadix with no more than 3 flowers visible per spiral from any angle; chromosome number 2N = 10 or 20.
section Leptanthurium  Schott

Roots usually greenish, lacking velamen; blades various, usually with the primary lateral veins conspicuously more prominent than the interprimary veins (except for section Urospadix);  stems various; cataphylls usually dilacerating (except section Calomystrium and some in section Belolonchiurn with cordate blades); number of flowers per spiral various but usually more than 3.

12.

13.

Blades usually lanceolate or oblong-lanceolate or oblong, less frequently oblong-elliptic, acute to obtuse or rarely truncate at the base, the primary lateral veins frequently numerous and scarcely more prominent than the interprimary veins; stems usually short; internodes short; principally species from eastern South America, especially southeastern Brazil.
section Urospadix Engl.

13.

Blades various, oblong to cordate, usually with the primary lateral veins conspicuously more prominent than the interprimary veins.

14.

Stems conspicuously elongate, usually less than 20 mm diam.; plants erect to scandent; blades chiefly much longer than broad, mostly oblong or nearly so, generally acute, obtuse to rounded at the base, rarely cordate.

15.

Pistils prominently exserted long before anthesis and many times longer than stamens when they appear.
section Decurrentia Croat sect. nov.

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