Perennial with short, small rhizome and elongate runners. Leaves emersed with lanceolate to ovate blades 8-20 x 1.5-7 cm, frequently with 1 or 2 basal lobes to 8 cm long and 2 cm wide. Scape simple with 2-5 distant whorls of flowers. Bracts 1-2 cm long, at first strongly connate and membranous, at length nearly free and thickish. Pistillate flowers with thickish, recurved pedicels (ascending in youth) 4-15 cm long; sepals more or less reflexed, 0.7-1 cm long; petals ca. twice as long; stamens frequently present, non-functional, in a ring. Staminate flowers with 18-[infinity] stamens, the glabrous, gradually tapering filaments 2.5-3.3 mm long, the oblong anthers 1.8-2.1 mm long. Mature receptacle 1-1.3 cm in diameter; achenes obovate, 2.8-3.1 x 2-2.5 mm, the dorsal wing ca. 0.6 mm wide, somewhat wider than the ventral wing, the erect, subapical, thick-based beak 0.3-0.7 mm long, variously curved. (FIG. 9b-d.) Perennial herbs, from stolons and/or corms, glabrous, to 25 cm tall; stolons to 15 cm long, to 0.7 cm wide; corms to 1.5 cm long, to 1.5 cm diam. Leaves emersed, petiolate, the petioles triangular, 12-13 cm long, 3-7 mm wide, the basal sheath to 6 cm, the blades pale green, sagittate or hastate or very rarely ellipt, 8.5-24.5 cm long, 0.7-6.1 cm wide, the veins 7-9, the apex acute to obtuse, the basal lobes present or rarely absent, 1-6.5 cm long, the tips separated by 1.5-15 cm, with 3-4 veins. Inflorescence a simple scape of 3-5 whorls, emersed, 5.5-16.5 cm long, 3-11.5 cm wide, the whorls with 3 flowers; peduncles triangular, 12-34 cm long, 0.4-0.8 cm diam.; staminate bracts separate, lanceolate, delicate, 7-11 mm long, the apex obtuse; carpellate bracts separate, lanceolate, delicate, to 12.5, the apex obtuse; staminate pedicels spreading, cylindric, 0.6-3.2 cm long, 0.8-1.2 mm diam.; carpellate pedicels flower and in fruit, cylindric, 1.5-11.5 cm long, 0.7-3.5 mm diam. Staminate flowers without sterile carpels, the sepals reflexed to spreading, 6-8.5 mm long, 2.5-4 mm wide, the petals clawed, ca. 1.5 cm long, ca. 1.6 cm wide, the claw ca. 2 mm long, the stamens 12-16, the filaments glabrous, dilated, 2-3 mm long, ca. 0.3 mm wide, the anthers linear, 1.5-1.9 mm long, ca. 0.6 mm wide, the apex obtuse; carpellate flowers without ring of sterile stamens, the sepals reflexed to spreading in flower and fruit, 7-8 mm long, 4-5.8 mm wide, the petals clawed, ca. 1.5 cm long, ca. 1.2 cm wide, the claw ca. 4 mm long. Fruit aggregate 1.1-1.7 cm diam.; achenes oblanceolate, beaked, without keel, 3.1-3.5 mm long, ca. 2.4 mm wide, the faces etuberculate, with 0-1 glands, the beak lateral, erect, 0.6-1.2 mm long. Distribution: Mexico; apparently limited to the region around Mexico City, there, on the basis of the numerous collections, locally abundant in lakes and ponds. (FIG. 9.) Central Mexico. Perennial herbs, from stolons and/or corms, glabrous, to 25 cm tall; stolons to 15 cm long, to 0.7 cm wide; corms to 1.5 cm long, to 1.5 cm diam. Leaves emersed, petiolate, the petioles triangular, 12-13 cm long, 3-7 mm wide, the basal sheath to 6 cm, the blades pale green, sagittate or hastate or very rarely ellipt, 8.5-24.5 cm long, 0.7-6.1 cm wide, the veins 7-9, the apex acute to obtuse, the basal lobes present or rarely absent, 1-6.5 cm long, the tips separated by 1.5-15 cm, with 3-4 veins. Inflorescence a simple scape of 3-5 whorls, emersed, 5.5-16.5 cm long, 3-11.5 cm wide, the whorls with 3 flowers; peduncles triangular, 12-34 cm long, 0.4-0.8 cm diam.; staminate bracts separate, lanceolate, delicate, 7-11 mm long, the apex obtuse; carpellate bracts separate, lanceolate, delicate, to 12.5, the apex obtuse; staminate pedicels spreading, cylindric, 0.6-3.2 cm long, 0.8-1.2 mm diam.; carpellate pedicels flower and in fruit, cylindric, 1.5-11.5 cm long, 0.7-3.5 mm diam. Staminate flowers without sterile carpels, the sepals reflexed to spreading, 6-8.5 mm long, 2.5-4 mm wide, the petals clawed, ca. 1.5 cm long, ca. 1.6 cm wide, the claw ca. 2 mm long, the stamens 12-16, the filaments glabrous, dilated, 2-3 mm long, ca. 0.3 mm wide, the anthers linear, 1.5-1.9 mm long, ca. 0.6 mm wide, the apex obtuse; carpellate flowers without ring of sterile stamens, the sepals reflexed to spreading in flower and fruit, 7-8 mm long, 4-5.8 mm wide, the petals clawed, ca. 1.5 cm long, ca. 1.2 cm wide, the claw ca. 4 mm long. Fruit aggregate 1.1-1.7 cm diam.; achenes oblanceolate, beaked, without keel, 3.1-3.5 mm long, ca. 2.4 mm wide, the faces etuberculate, with 0-1 glands, the beak lateral, erect, 0.6-1.2 mm long. Distribution: Mexico; apparently limited to the region around Mexico City, there, on the basis of the numerous collections, locally abundant in lakes and ponds. (FIG. 9.) Perennial with short, small rhizome and elongate runners. Leaves emersed with lanceolate to ovate blades 8-20 x 1.5-7 cm, frequently with 1 or 2 basal lobes to 8 cm long and 2 cm wide. Scape simple with 2-5 distant whorls of flowers. Bracts 1-2 cm long, at first strongly connate and membranous, at length nearly free and thickish. Pistillate flowers with thickish, recurved pedicels (ascending in youth) 4-15 cm long; sepals more or less reflexed, 0.7-1 cm long; petals ca. twice as long; stamens frequently present, non-functional, in a ring. Staminate flowers with 18-[infinity] stamens, the glabrous, gradually tapering filaments 2.5-3.3 mm long, the oblong anthers 1.8-2.1 mm long. Mature receptacle 1-1.3 cm in diameter; achenes obovate, 2.8-3.1 x 2-2.5 mm, the dorsal wing ca. 0.6 mm wide, somewhat wider than the ventral wing, the erect, subapical, thick-based beak 0.3-0.7 mm long, variously curved. (FIG. 9b-d.)General Information
Source: [
Source: [
Distribution
Source: [
Flora Neotropica
DistributionMemoirs of the New York Botanical Garden
Distribution
