PLANT: Perennial tendril-climbing vines, rarely shrubs or small trees. LEAVES: often heteroblastic, usually bearing extrafloral nectaries on the petiole and/or lamina; tendrils axillary, simple in ours. INFLORESCENCE: with peduncles paired or solitary, arising colateral to the tendril; peduncles articulate distal to the bracts; bracts in ours setaceous to foliaceous or pinnatifid. FLOWERS: perfect (sometimes pistil-sterile); perianth sometimes connate/adnate basally into a conspicuous floral tube, floral cup, or hypanthium, but this only flattish to campanulate in AZ plants; sepals 5; petals 5 in ours; corona 1-many series of often showy filaments, the innermost series usually connate and membranous, shielding the nectar chamber, and called the operculum; extrastaminal nectariferous disk (limen) present as ring or cup around base of androgynophore; stamens 5 in ours, borne on an elongate androgynophore; carpels 3 in ours, the stigmas 3, the ovary borne on androgynophore. FRUITS: mostly berries. SEEDS: arillate, dark, compressed, punctate-reticulate or transversely grooved. SEEDS: arillate, dark, compressed, punctate-reticulate or transversely grooved. NOTES: 500 spp.; mainly neotropical regions. (for the passion, or suffering, of Christ). Killip, E. P. 1938. Publ. Field Mus. Nat. Hist., Bot. Ser. 19:1-613. MacDougal, J. M. 1994. Syst. Bot. Monogr. 41:1-146. REFERENCES: MacDougal, John M. 2001. Passifloraceae. J. Ariz. - Nev. Acad. Sci. Volume 33(1).