Urena
L.
Annual or perennial undershrubs or shrubs; young parts densely minute stellate-
hairy. Leaves palmi-lobed to-parted or undivided, angular, palminerved with nectaries
on nerves beneath. Flowers axillary, solitary or in clusters. Epicalyx campanulate,
5-lobed, lobes connate at base. Calyx campanuiate, 5-lobed, lobes ovate or ovate-lanceolate, connate at base with 1-nerved nectaries. Corolla rotate, pink, purplish-red,
stellate-pilose outside; petals 5. Staminal column as long as petals, truncate or denticulate at apex; antheriferous towards tip; anthers subsessile. Ovary depressed globose,
5-loculed, locules uniovulate; styles divided from about middle into 10 arms, reflexed;
stigmas discoid or capitate, papillose. Schizocarps subglobose; mericarps 5, separating
at maturity, triangularly obovoid, dorsally convex and covered with glochidiate spines,
indehiscent. Seeds obovoid-trigonous, glabrous, ascending.
Monotypic, pantropical.
Notes. Linnaeus (1753) in his Species Plantarum described 3 species under Urena, viz. U. lobata, U. sinuata and U. procumbens. Subsequently several botanists described many other species and varieties. Guerke (Fl. Brasiliensis 12, 3: 457 - 596. 1892) maintained 2 Linnaean species, viz. U. lobata and U. sinuata with 9 and 2 varieties respectively. Hochreutiner (Ann. Cons. jard. Bot. Geneve 5: 131 - 145. 1901) retained only one species (U. lobata) with 14 varieties, subsequently adding 3 more. Most botanists (Masters 1874, Cooke 1901, Gamble 1915, etc.) dealing with Indian species of Urena oaintained 2 species viz., U.lobata L. and U. sinuata L. Borssum Waalkes (1966) maintained only U. lobata with 2 subspecies, viz. lobata end sinuata based mainly on epicalyx characters and in each subspecies he included 2 varieties. All taxa recognised by Borssum Waalkes occur in India. After studying these taxa in field and herbarium, Borssum Waalkes's view is followed in this flora.
Monotypic, pantropical.
Notes. Linnaeus (1753) in his Species Plantarum described 3 species under Urena, viz. U. lobata, U. sinuata and U. procumbens. Subsequently several botanists described many other species and varieties. Guerke (Fl. Brasiliensis 12, 3: 457 - 596. 1892) maintained 2 Linnaean species, viz. U. lobata and U. sinuata with 9 and 2 varieties respectively. Hochreutiner (Ann. Cons. jard. Bot. Geneve 5: 131 - 145. 1901) retained only one species (U. lobata) with 14 varieties, subsequently adding 3 more. Most botanists (Masters 1874, Cooke 1901, Gamble 1915, etc.) dealing with Indian species of Urena oaintained 2 species viz., U.lobata L. and U. sinuata L. Borssum Waalkes (1966) maintained only U. lobata with 2 subspecies, viz. lobata end sinuata based mainly on epicalyx characters and in each subspecies he included 2 varieties. All taxa recognised by Borssum Waalkes occur in India. After studying these taxa in field and herbarium, Borssum Waalkes's view is followed in this flora.
