Ilex curtissii
Ilex curtissii, commonly known as Suwanee possum-haw or Curtiss's holly, is a species of flowering plant in the family Aquifoliaceae. It is endemic to the southeastern United States, where it is restricted primarily to the Suwannee River drainage of southern Georgia and northern Florida.
Description
Ilex curtissii is a deciduous shrub or small tree in the genus Ilex. It bears simple, toothed leaves and produces small flowers followed by red drupaceous fruits.
It is most similar to Ilex decidua, from which it differs in having smaller leaves (2–4.8 cm long and 0.6–1.5 cm wide), smaller fruits (4–5 mm in diameter), and sepals that are typically ciliate. The leaves are often gray-green and somewhat revolute, particularly toward the base, and the lower surface is tomentose, especially along the midrib.
In contrast, Ilex decidua has larger leaves (typically 4.5–8.5 cm long), larger fruits, and sepals that are not ciliate.
Taxonomy
The species was originally described as Ilex decidua var. curtissii by Merritt Lyndon Fernald in 1902 and elevated to species rank by John Kunkel Small in 1933 in Manual of the Southeastern Flora. The basionym is retained in synonymy in modern taxonomic databases.
Modern treatments support recognition of Ilex curtissii as a species distinct from Ilex decidua, with the two taxa considered allopatric and not overlapping in range.
Distribution and habitat
Ilex curtissii occurs in the southeastern coastal plain of the United States, primarily in northern Florida and extreme southern Georgia, especially within the Suwannee River drainage and also extending into the St. Marys River drainage.
It inhabits floodplains and moist forests, including riverbanks, hammocks, and seasonally wet woodlands.
Occurrence data compiled by the Global Biodiversity Information Facility (GBIF) indicate over 200 documented records, primarily from herbarium collections and research observations.
Phenology
Flowering occurs from mid-March to mid-April, with fruiting from September to October.
Ecology
Ilex curtissii is associated with moist to wet habitats and is considered a facultative wetland species (FACW), indicating that it commonly occurs in wetlands but may also be found in adjacent upland environments.
Conservation
Ilex curtissii has a NatureServe global conservation rank of G3, indicating that it is vulnerable due to a relatively restricted range and a limited number of occurrences. Estimates suggest that there are approximately 6 to 20 populations rangewide, with threats including habitat fragmentation, residential development, and forestry practices.
Although additional populations may exist that have historically been misidentified as Ilex decidua, the species remains of conservation concern due to its limited distribution.