Asarum finzelii
| Asarum finzelii | |
|---|---|
| Asarum finzelii in flower | |
| Asarum finzelii front-view of flower | |
| Scientific classification | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Magnoliids |
| Order: | Piperales |
| Family: | Aristolochiaceae |
| Genus: | Asarum |
| Species: | A. finzelii
|
| Binomial name | |
| Asarum finzelii (B.R.Keener) Diamond[2]
| |
| Synonyms[3] | |
| |
Asarum finzelii is a species of flowering plant in the family Aristolochiaceae. It is endemic to Marshall County, Alabama.[3]
Description
Asarum finzelii is a terrestrial, acaulescent perennial herb arising from a short rhizome.[4] The leaf petioles are up to 23 cm long, and the blades are hastate-sagittate with rounded basal lobes, though sometimes triangular or nearly cordate; the largest leaves are 8–12(15) cm long and 8–10(12) cm wide.[4]
The flowers are borne on peduncles 2–5 cm long.[4] The calyx is 25–30 mm long and 16–19 mm wide, rounded at the base, and divided into two parts by an abrupt outward flare.[4] The lower calyx tube is campanulate and 4–7 mm long, while the upper tube is more or less cup-shaped or short-cylindric and 10–11 mm long.[4] The three calyx lobes are erect, broadly triangular, wider than long, and 8–12 mm long by 15–16 mm wide.[4]
The flowers are similar to those of A. speciosum and A. arifolium, but differ from A. speciosum in having erect rather than recurved calyx lobes, a distinctly shorter lower calyx tube, and maroon rather than greenish style appendages; they differ from A. arifolium in having an open, cup-shaped calyx rather than an urceolate one.[4]
Distribution and habitat
Asarum finzelii is known only from two populations on Bishop Mountain in Marshall County, Alabama.[4] The type locality is along the north side of the Tennessee River, west of Hambrick Hollow, northwest of Guntersville.[4]
The species occurs in the Plateau Escarpment portion of the southwestern Appalachians, near the boundary of the Pennington Formation and Bangor Limestone, with occasional Pottsville Sandstone debris.[4] Its habitat is slightly mesic, with rocky, well-drained soil in regenerated forest several decades old.[4] The canopy is composed mostly of hardwoods, including oaks, hickories, sweetgum, and tulip poplar, with occasional cedar and pine.[4]
Taxonomy
The species was first described as Hexastylis finzelii by Brian R. Keener in 2020.[4] In 2023, Alvin R. Diamond transferred it to Asarum as Asarum finzelii.[2]
The transfer reflects a broader taxonomic treatment in which Hexastylis is included within a more broadly circumscribed Asarum, based on morphological and molecular evidence indicating that Hexastylis is not monophyletic.[2]
Asarum finzelii belongs to the informal arifolia–speciosa group, whose members are characterized by leaves mottled with lighter green between the primary veins and style extensions bifid to the stigmas.[4]
Etymology
The specific epithet honors Brian Finzel, who discovered the first known population of the species.[4] Keener proposed the common name "Finzel's wild ginger".[4]
Conservation status
The species has not been evaluated by the International Union for Conservation of Nature (IUCN). In its original description, Keener recommended that it be considered Endangered under IUCN criteria because of its extremely narrow distribution.[4]
References
- ^ "Hexastylis finzelii". NatureServe Explorer. NatureServe. Retrieved 17 March 2026.
- ^ a b c Diamond, Alvin R. (2023). "New combinations in Asarum (Aristolochiaceae) for two recently described Hexastylis species". Journal of the Botanical Research Institute of Texas. 17 (2): 427–429. doi:10.17348/jbrit.v17.i2.1321.
- ^ a b "Asarum finzelii (B.R.Keener) Diamond". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 2026-03-17.
- ^ a b c d e f g h i j k l m n o p q Keener, Brian R. (2020). "A new Hexastylis (Aristolochiaceae) from northeast Alabama (U.S.A.) with notes on the species "groups" within the genus". Journal of the Botanical Research Institute of Texas. 14 (2): 161–166. doi:10.17348/jbrit.v14.i2.999.