Pinguicula hemiepiphytica

Pinguicula hemiepiphytica is an 8–20 cm tall, carnivorous plant that grows on rocks or trees.[1]

There are two forms, distinguished by leaf type. In both forms, the leaves are arranged in dense whorls around the base of the stem.[2] The summer form of the plant has 4 to 12 nearly circular leaves that serve to catch small insects.[1] The leaves are covered in mucus, making the leaf surface sticky.[2] When an insect is caught, it triggers the secretion of digestive enzymes.[1] Leaf color is light green to purplish-pink.[1][3] The winter form of the plant has far more leaves than the summer form, but the leaves are shorter and narrower.[1] All glands are absent, so this form is not able to trap or digest insects.[1][2] The leaves are light green.[1]

During the summer months, individuals bear up to three solitary flowers.[1] Flowers are perfect, bilaterally symmetrical, have a five lobed corolla, and are purple to pink in color.[1][4] The corolla tube extends beyond the flower's point of attachment to the stem, forming a spur.[1][4]

Pinguicula hemiepiphytica has only been documented in the cloud forests of Sierra de Juarez, Mexico, although it is suspected to exist in neighboring areas with a similar environment.[1] Its habitat is very wet, and they typically grow with colonies of mosses.[1] The long spur of the flower is a trait that Pinguicula species pollinated by butterflies, moths, and birds have in common.[5] The species is believed to be hummingbird pollinated, given the length of the floral spur.[6] It has been found that species in this group do not offer food rewards in their floral trichomes to pollinators.[5] Like most Pinguicula, they can also self-pollinate and reproduce vegetatively.[2]

Carnivory in plants is an adaptation for nutrient acquisition in nutrient poor soils.[7] The roots mainly serve to adhere the plant to its substrate and absorb water.[2] Growing on a vertical surface exposes the plant to more sunlight, and water that runs down the sides of the trees and rocks they are growing on.[1][2]

The term “pinguis” is Latin for “grease”, which suits this genus that uses its sticky and greasy leaves to trap prey.[8] This adaptation can be employed by plant collectors to control fungus gnat populations [9][10]

Pinguicula hemiepiphytica is most commonly cultivated for use in the nursery trade. Mexican Pinguicula are popular for being relatively easy to grow; P. hemiepiphytica is cultivated and sometimes hybridized with other species for sale to hobbyists.[11][12][13][14] Biological resource use is also associated with this species; 22% of Pinguicula species are illegally poached and traded for biological uses that are rarely medicinal or pharmaceutical [7]

In Oaxaca, Mexico where these species are native, the Zapotec use P. moranensis to treat “culture-bound syndromes'', including “mal de ojo” and “susto”.[15][16] Until 1991, P. hemiepiphytica was considered to be a variety of P. moranensis because of their similar morphologies and range; it's possible that both species are used by the Zapotec[1][15]