8. Scapes with 2-5 flowers; bracts subtending flowers 

 unlobed; submersed, bladder-bearing branches often 

 with small, apetalous cleistogamous flowers (fig. 

 4D); branches finer, segments entire, except for 

 small spicules at tips (magnification needed). 

 6. U. geminiscapa 



8. Scapes with 6-12 flowers; bracts subtending flowers 

 with basal lobes; cleistogamous flowers absent; 

 branches coarser, segments with spicules along 

 margins (fig. 4B) (magnification needed). 

 7. U. vulgaris 



7. Leaf-like branches divided 1-3 times; creeping over wet 

 mud or in shallow water, or in tangled masses floating 

 in shallow water; plants small, slender, less than 

 30 cm long. 



9. Flower spur much shorter than lower lip of corolla, 

 thick, obtuse, 3.0-3.5 mm long (fig. IF); lower lip of 

 corolla 5-6 mm long; leaf-like branches with mostly 

 2 segments. 

 8.U. gibba 



9. Flower spur somewhat shorter to slightly longer 

 than lower lip of corolla, narrow, conic, usually 

 curved, more than 4 mm long; lower lip of corolla 

 8-10(-15) mm long; leaf-like branches with 3 or more 

 segments (usually forked twice). 



9. U. biflora 



1. Plants anchored in substrate, apparent only when flowering, 

 appearing terrestrial (vegetative grass-like branches sometimes 

 emergent, or sometimes floating in densely tangled mats due to 

 wave action (fig. 51). 



10. Flowers yellow (rarely purplish or white); bracts along scape 

 alternate (fig. 5A,D); flowers (l-)2-12. 



11. Flowers clearly pedicellate; bract at base of pedicel peltate 

 (fig. 5B); spur of corolla appressed to lower lip (fig. 5C). 



10. U. subulata 



11. Flowers subsessile; bract at base of flower attached basally 

 (fig. 5E); spur of corolla divergent (fig. 5D). 



11. U. cornuta 



10. Flowers purple; bracts along scape paired, fused (fig. 5F,G); 

 flowers 1. 

 12. U. resupinata 



