Endodeca is a small genus of perennial herbaceous plants in the birthwort family, Aristolochiaceae, within the order Piperales. It was established by the botanist Constantine Samuel Rafinesque in 1828 in his work Medical Flora, and the GBIF Backbone Taxonomy recognizes it as an accepted genus containing two species. Many other treatments, however, do not maintain Endodeca as separate: Wikipedia and several floras place both species within the much larger genus Aristolochia (which itself contains more than 500 species), where they are known instead as Aristolochia serpentaria and Aristolochia reticulata. This reflects an ongoing disagreement in Aristolochiaceae classification over whether small-flowered, non-climbing North American segregates like Endodeca merit generic status apart from Aristolochia.
The two species are Endodeca serpentaria (Virginia snakeroot) and Endodeca reticulata (Red River snakeroot, Texas Dutchman's pipe, or Texas pipevine). Unlike the woody, twining lianas typical of the broader Aristolochia, both are low, non-climbing perennial herbs. Endodeca serpentaria has heart-shaped leaves and small, curved, pipe-shaped flowers characteristic of the family; Endodeca reticulata grows erect to sprawling, to about 0.4 meters tall, and flowers in late spring and summer. Across Aristolochiaceae generally, flowers are inflated at the base and continue into a long perianth tube ending in a tongue-shaped lobe, with inward-pointing hairs that temporarily trap pollinating insects until they wither and release them.
Endodeca species are confined to eastern and south-central North America. Endodeca serpentaria ranges from Connecticut and southern Michigan south to Texas and Florida, while Endodeca reticulata is more narrowly distributed, endemic to Arkansas, Louisiana, Oklahoma, and Texas, where it favors moist, sandy soils. Endodeca serpentaria serves as a larval host plant for the pipevine swallowtail and polydamas swallowtail butterflies.
Historically, Endodeca serpentaria (as Virginia snakeroot) held a place in both Cherokee and European folk medicine: the Cherokee chewed and applied the root to snakebite wounds, it was used as a remedy for ague in 18th-century England, and it served as a flavoring ingredient in bitters. The species is now considered rare across parts of its northern range — listed as endangered in New York, a species of special concern in Connecticut, and classified as Threatened in Michigan.
Distribution
Endodeca is restricted to eastern and south-central North America. E. serpentaria occurs from Connecticut and southern Michigan south to Texas and Florida; E. reticulata is endemic to Arkansas, Louisiana, Oklahoma, and Texas.
Ecology
E. serpentaria is a larval host plant for the pipevine swallowtail and polydamas swallowtail butterflies. E. reticulata grows in moist, sandy soils and flowers in late spring and summer.
Conservation
E. serpentaria (Virginia snakeroot) is listed as an endangered species in New York (no records 1895–1994, now scattered populations), a species of special concern in Connecticut, and has a status of "Threatened" in Michigan.
Cultural Uses
The root of E. serpentaria was chewed and applied to snakebite wounds in Cherokee traditional medicine, used as a folk remedy for ague in 18th-century England, and used as an ingredient in bitters.
Taxonomy Notes
GBIF's Backbone Taxonomy accepts Endodeca Raf. (published 1828, Medical Flora 1: 62) as a distinct genus of 2 species in Aristolochiaceae, order Piperales. Wikipedia and other treatments do not maintain this separation, instead placing both species within the much larger genus Aristolochia (as A. serpentaria and A. reticulata). Sources disagree on whether Endodeca is a valid genus.
