Passiflora mexicana
Passiflora mexicana, commonly known as the Mexican passionflower, is a species of flowering plant in the family Passifloraceae. It is a perennial climbing vine native to Arizona and much of Mexico. It grows primarily in seasonally dry tropical and subtropical environments, including thickets along streams, riparian washes, rocky slopes, and occasionally dry mesas.
The species is readily distinguished by its smooth, two-lobed leaves, greenish flowers with a red to reddish-purple corona, and small purplish-black fruits.
Description
Passiflora mexicana is a perennial vine. It climbs through surrounding vegetation using coiling axillary tendrils. The stems, leaves, and other vegetative structures are generally glabrous.
The leaves are alternately arranged and distinctly divided into two broad lobes. The leaf margins are entire, and the blades may occasionally be variegated or marked with pale spots. Small nectar-producing glands occur on the lower surface of the leaf blade between the principal veins. The leaf stalks, or petioles, lack glands. The stipules are narrow, ranging from bristle-like to linear-triangular, and are slightly curved.
The flower stalks are borne singly or in pairs beside the tendrils. Each flower stalk is jointed beyond its small bracts. The bracts are bristle-like to narrowly lance-shaped and may have three small teeth.
The sepals are light green or yellowish green and are much longer and more conspicuous than the small petals. The floral corona consists of two rows of filaments. The outer filaments are red or reddish purple and longer than the inner filaments. The ovary is glabrous or nearly so.
The fruit is a subglobose to broadly ellipsoid berry. It becomes purplish black when mature. The seeds have transverse grooves.
The foliage has been described as having a strong or pungent odor.
Taxonomy
Passiflora mexicana was described by French botanist Antoine Laurent de Jussieu in 1805. The name was published in volume 6 of the Annales du Muséum National d'Histoire Naturelle, on page 108, accompanied by an illustration. The specific epithet mexicana refers to Mexico, from which the species was originally described.
Distribution
Passiflora mexicana is native from southeastern Arizona south through Mexico.
In the United States, the species is restricted to Arizona, where it has been reported from Cochise, Graham, Pima, Pinal, and Santa Cruz counties.
Its Mexican range is considerably broader and includes both northern and tropical portions of the country.
Habitat and ecology
In Arizona, Passiflora mexicana grows in thickets near riparian areas and washes, generally at elevations of approximately . It may climb through shrubs and small trees along intermittent streams or grow on rocky slopes and dry mesas.
It is primarily associated with the seasonally dry tropical biome. Across its wider Mexican range, it also occurs in dry forest, thorn scrub, and other seasonally dry vegetation communities.
Flowering in Arizona generally occurs from July through October, with fruits also developing during this period. Some regional sources give the principal flowering season as July and August, occasionally continuing into October.
Conservation
NatureServe assigns Passiflora mexicana a global conservation rank of G3G5, indicating uncertainty ranging from vulnerable to secure. Its rounded global rank is G4, or apparently secure. The assessment was last reviewed on 30 December 1994 and is identified by NatureServe as needing review.
Within the United States, NatureServe has not assigned the species a national conservation rank. It is ranked S3, or vulnerable, in Arizona.
The species has no status under the United States Endangered Species Act.
Common names
English common names include Mexican passionflower and Mexican passion flower. Spanish names reported for the species include ojo de venado, díctamo real, and ítamo real.
References
mexicana Category:Flora of Arizona Category:Flora of Mexico Category:Plants described in 1805