I would like a key to distinguish all the taxa, or at least those closely related to F. hexapetala. Phylogeography and phylogenetic studies would be interesting too.
Gbolade AA, Olayemi JO, Elujoba AA, Sofowora A, Adesina SK. 1992 Factors affecting the levels of steroidal sapogenins in Nigerian Agave and Furcraea species Fitoterapia 63. 45-48. (EBBD, 190204324).
Bogler DJ, Simpson BB. 1995 A chloroplast DNA study of the Agavaceae. Syst. Bot. 20. 191-205. 40 taxa. Agav:Dracaena, Sansevieria, Beaucarnea, Calibanus, Dasylirion, Nolina, Beschorneria, Agave, Manfreda, Polianthes, Prochnyanthes, Furcraea, Yucca, Hesperaloe. Hypox:Hypoxis. Lili:Asparagus, Aspidistra, Convallaria, Liriope, Maianthemum, Cordyline, Hemerocallis, Hosta. Xanthor:Xanthorrhoea. (PMBD, 186000297).
Alvarez de Zayas A. 1996 El genero Furcraea (Agavaceae) en Cuba. (The genus Furcraea (Agavaceae) in Cuba.) An. Inst. Biol. Univ. Nac. Auton. Mex., Bot. 67. (2): 329-346 (1996) - illus. Icones, Maps, Anatomy and morphology, Keys. Furcraea antillana sp. nov. Geog=4 (KR, 199700692).
Souza Chies TT, Bittar G, Nadot S, Carter L, Besin E, Lejeune B. 1997 Phylogenetic analysis of Iridaceae with parsimony and distance methods using the plastid gene rps4. Pl. Syst. Evol. 204. 109-123. Alophia, Aristea, Babiana, Belamcanda, Bobartia, Crocosmia, Crocus, Cypella, Dietes, Freesia, Gladiolus, Iris, Isophysis, Lapeirousi a, Libertia, Micranthus, Moraea, Neomarica, Nivenia, Patersonia, Pillansia, Romulea, Sisyrinchium, Sparaxis, Tigridia, Trimezia, Wat sonia, Agav:Agave, Asparagus, Furcraea, Haemanthus, Hymenocallis, Narcissus, Nerine, Yucca. (PMBD, 186001815).
Khan HA. 1997 Morphotaxonomical studies of Furcraea (Agavaceae) of India. J. Pl. Anat. Morphol. 7. (2): 140-147 (1997) - illus. Icones, Keys. Geog=6 (KR, 199904195).
Garcia Mendoza A. 1999 Una especie nueva de Furcraea (Agavaceae) de Chiapas, Mexico. Novon 9. (1): 42-45 (1999) - illus. Icones, Anatomy and morphology. Furcraea niquivilensis sp. nov. Geog=4 (KR, 199900858).
Garcia Mendoza A. 2000 Revision taxonomica de las especies arborescentes de Furcraea (Agavaceae) en Mexico y Guatemala. Bol. Soc. Bot. Mex. no.66. 113-129 (2000) - illus. Icones, Maps, Chromosome numbers, Anatomy and morphology, Keys. Furcraea martinezii sp. nov. Geog=4 (KR, 200200674).
Nadaf AB, Shukla SR, Krishnan S. 2001 Some new observations in Furcraea foetida L. J. Econ. Taxon. Bot. 25. (2): 275-278 (2001) - illus. Icones, Anatomy and morphology. Geog=6 (KR, 200203359).