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KEY TO THE SPECIES OF DRACONTIUM L.
1. Blade segments linear, 1-1.5 cm wide, usually ascending at " 45E angle from the petiole; growing in seasonal swamps; Venezuela (Apure), Brazil (Mato Grosso do Sul), and Paraguay. 13. D. margaretae. 1. Blade segments not linear, 3-12 cm wide, spreading horizontally or ascending at " 45E angle from the petiole when young; growing in habitats other than seasonal swamps; Southern Mexico to Central Paraguay. 2. Peduncle completely subterranean or not more than 10 cm above ground level; longest bracteole reaching to base of or covering to 1/2 of the spathe. 3. Spathe cymbiform (boat-shaped), not at all constricted; spadix never with appendages at apex. 4. Spadix often hidden at anthesis; spathe margins broadly overlapping at the base for at least 1/2 of the spathe. 5. Spathe 28-35 cm long, 6-10 cm wide at anthesis; endemic to Par< State, Brazil. 14. D. nivosum 5. Spathe never more than 20 cm long and 4.5 cm wide at anthesis; Brazil, Venezuela, and Peru. 6. Inner surface of spathe semiglossy to velvety, never with transparent scales. 7. Spathe (6)10-13 cm long, 3.5-4.5 cm wide, arching by 45E to 90E apically; transparent area (at base of inner spathe surface) obscure; Amazonian Peru, Venezuela and Brazil. 1. D. amazonense 7. Spathe (10)15-18 cm long, 3.2-4 cm wide, slightly arching (by up to 45E) apically; transparent area (at base of inner spathe surface) 0.5-1 cm high; known from southern Venezuela and adjacent Brazil. 19. D. prancei 6. Inner surface of spathe covered with transparent scales. 8. Seeds reniform, laterally concave, with small cells along dorsal ridge; endemic to Gois, Brazil. 5. D. bogneri 8. Seeds rounded, laterally convex, smooth along dorsal ridge; endemic to eastern Acre, Brazil. 23. D. ulei 4. Spadix exposed (visible from face view outside) at anthesis; spathe margins slightly to hardly overlapping at the base; French Guiana, Surinam, Guyana and Brazil. 18. D. polyphyllum 3. Spathe not cymbiform (not boat-shaped), constricted in lower 1/5 to 1/2 and differentiated into a proximal tube and a distal lamina; spadix often with one to several appendages (elongated and enlarged tepals) at apex. 9. Inner surface of spathe semiglossy or velvety, never with transparent scales. 10. Seeds with 5-6 thin, strongly interrupted ridges to 1.5 mm high; tropical wet forests, DariJn, Panama to Choc\, Colombia. 10. D. grayumianum 10. Seeds with 3 continuous ridges to 0.5 mm high; tropical moist forests, southern Mexico to central Panama. 21. D. soconuscum 9. Inner surface of spathe densely covered with, transparent scales. 11. Seeds with 4 or 5 thin, strongly interrupted ridges to 1.5 mm high; endemic to Venezuela. 6. D. changuango 11. Seeds with 3 continuous ridges to 0.5 mm high; Caribbean coast of Colombia and Zulia State, Venezuela. 20. D. purdieanum 2. Peduncle 30-250 cm above ground level; longest bracteole confined to base of peduncle, never reaching the spathe. 12. Peduncle 30-90 cm long, less than half as long as petiole. 13. Spathe apex caudate, 3-5 times longer than the body of the spathe; berries apically pointed; endemic to Loreto State, Peru. 2. D. angustispathum 13. Spathe apex obtuse or acuminate, much shorter than the body of the spathe. 14. Spathe 58-78 cm long, 13-21 cm wide, obtuse at apex; seeds dark brown, 1-1.2 cm diam, with three dorsal ridges; Atlantic slope of Nicaragua and Costa Rica. 8. D. gigas 14. Spathe 9-20 cm long, 3-5 cm wide, acuminate at apex; seeds light brown, 0.5-0.7 cm diam, with 1 dorsal ridge; West Indies, Guianas, Venezuela and Brazil. 15. Spathe 9-10 cm long, slightly arching apically up to 45E angle; seeds laterally convex, with many fine pits flanking the ridge; French Guiana, near Brazilian border. 11. D. guianense. 15. Spathe 10-20 cm long, often arching apically by 45E-90E angle; seeds laterally concave, with coars, wart-like protuberences flanking the ridge; West Indies, Guianas, Venezuela and Brazil. 4. D. asperum 12. Peduncle 100-200 cm long, usually more than half as long as petiole. 16. Spathe cymbiform, never differentiated into a proximal tube and distal lamina. 17. Spathe obtuse at apex, widest in upper half. 18. Seeds rounded, the dorsal ridges 4 or 5, strongly interrupted; spathe green externally, the margins broadly overlapping; spadix hidden at anthesis; endemic to the west slope of the Andes in Ecuador and adjacent Colombia. 7. D. croatii 18. Seeds reniform, dorsal ridge 1, continuous; spathe maroon externally, the margins scarcely overlapping; spadix exposed at anthesis; endemic to the Pacific slope of Costa Rica. 16. D. pittieri 17. Spathe acuminate at apex, widest in lower half. 19. Spadix 23-35 cm long in fruit; petiole 2-6 m long; seeds rounded, with 3 strong, continuous ridges to 2 mm high; Amazonian Peru and Brazil. 15. D. peruvianum 19. Spadix 4-5 cm long in fruit; petiole 1-2 m long; seeds reniform, with 3 weak continuous ridges to 0.5 mm high; endemic to Acre State, Brazil. 12. D. longipes 16. Spathe usually not cymbiform, constricted near the base to yield a proximal tube and distal lamina. 20. Seeds 0.5-0.6 cm diam., laterally convex, with 1 dorsal ridge; spathe usually wrinkled or lobed along the margins; endemic to southern Peru. 17. D. plowmanii 20. Seeds 0.7-1 cm diam., laterally concave, with 3 dorsal ridges; spathe never wrinkled or lobed along the margins; Colombia, Ecuador, Peru, Brazil and Surinam. 21. Inner surface of spathe densely covered with transparent scales; Colombia, Ecuador and Peru. 3. D. asperispathum 21. Inner surface of spathe semiglossy or velvety. 22. Spathe 45-50 cm long, 10-15 cm wide, abruptly acuminate apically; Amazonian Ecuador and Peru. 9. D. grandispathum 22. Spathe 20-35 cm long, 3-6 cm wide, gradually acuminate apically; southern Costa Rica to Pacific Colombia, and Amazonian Ecuador, Peru, Brazil and Surinam. 22. D. spruceanum
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