Dicerandra

Classification System: APG IV

Superregnum: Eukaryota
Regnum: Plantae
Cladus: Angiosperms
Cladus: Eudicots
Cladus: Core eudicots
Cladus: Asterids
Cladus: Lamiids
Ordo: Lamiales

Familia: Lamiaceae
Subfamilia: Nepetoideae
Tribus: Mentheae
Subtribus: Menthinae
Genus: Dicerandra
Overview of species

D. densiflora – D. frutescens – D. fumella – D. linearifolia – D. odaratissima – D. radfordiana
Name

Dicerandra Benth., Edwards's Bot. Reg. 15: t. 1300 (1830)
Type species: Dicerandra linearifolia (Elliott) Benth. in A.P.de Candolle, Prodr. 12: 243 (1848)

Synonyms

Heterotypic
Ceranthera Elliott, Sketch Bot. S. Carolina 2: 93 (1821), nom. illeg.

References

Bentham, G. (1830) Edwards's Botanical Register 15: pl. 1300.
Govaerts, R. et al. 2014. Dicerandra in World Checklist of Selected Plant Families. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the internet. Accessed: 2014 June 26. Reference page.
Tropicos.org 2014. Dicerandra. Missouri Botanical Garden. Published on the internet. Accessed: 2014 June 26.
International Plant Names Index. 2014. Dicerandra. Published online. Accessed: June 26 2014.

Dicerandra is a genus of flowering plants in the mint family. Dicerandra comprises 11 species: six perennial and five annual species. The perennials have narrow ranges in Central Florida with small population sizes and only occur on ancient dune ridges along the Lake Wales Ridge or the Atlantic coastal ridge; the annual species occur more broadly on sandhill habitats to the north. The perennials’ habitat has been severely fragmented due to human development over the past century. As a result, all perennial species except one are listed as federally endangered.[1][2] Annual species of the clade have large ranges when compared to perennial members, with distributions of annuals ranging for hundreds of miles from the Panhandle of Florida to southeastern Georgia,[3] with the exception of Dicerandra radfordiana which is endemic to two sites along the Altamaha river. The genus is characterized by hornlike spurs on their anthers.[4]

The phylogenetics of this genus have been studied before; first by Robin Huck in 1987, who described Section Dicerandra, which includes all species with standard-lobed corollas and exserted stamens, and section Lecontea which includes D. odoratissima and D. radfordiana that have cucullate-lobed corolla species with inserted stamens.[5] Subsequent studies by plant systematists at the University of Florida have confirmed these sections, in addition to discovering a potential chloroplast capture event in Dicerandra immaculata var savannarum.[3]

Ecology

Dicerandra species are found along ancient sand-hill habitats in the southeastern US.[3] Northern, annual taxa occur mostly on acidic white sand that are remnants of ancient shorelines during the Pleistocene. Southern perennials either occur on red sands along the Lake Wales Ridge or on white sands along the Atlantic coast. They prefer open habitats free from tree cover and rapidly draining soils. Some, like Dicerandra cornutissima, have been reported along Interstate 75 where frequent machine clearing have provided a suitable habitat.[5]
Species

[1]

Dicerandra christmanii Huck & Judd = Dicerandra frutescens var. christmanii (Huck & Judd) D.B.Ward
Dicerandra cornutissima Huck = Dicerandra frutescens var. cornutissima (Huck) D.B.Ward
Dicerandra densiflora Benth. - northern Florida
Dicerandra frutescens Shinners - scrub mint - central Florida
Dicerandra fumella Huck - Florida panhandle, southern Alabama
Dicerandra immaculata Lakela - Lakela's mint = Dicerandra frutescens var. immaculata (Lakela) D.B.Ward
Dicerandra linearifolia (Elliott) Benth. - coastal plain mint - southern Georgia, southern Alabama, northern Florida
Dicerandra modesta (Huck) Huck = Dicerandra frutescens subsp. modesta Huck
Dicerandra odoratissima R.M.Harper - rose balm - southern South Carolina, southeastern Georgia
Dicerandra radfordiana Huck - Radford's balm - McIntosh County in Georgia
Dicerandra thinicola H.A.Mill - Titusville mint = Dicerandra frutescens subsp. thinicola (H.A.Mill.) D.B.Ward

References

Kew World Checklist of Selected Plant Families
Biota of North America Program, 2013 county distribution maps
Oliveira, Luiz O.; Huck, Robin B.; Gitzendanner, Matthew A.; Judd, Walter S.; Soltis, Douglas E.; Soltis, Pamela S. (2007-06-01). "Molecular phylogeny, biogeography, and systematics of Dicerandra (Lamiaceae), a genus endemic to the southeastern United States". American Journal of Botany. 94 (6): 1017–1027. doi:10.3732/ajb.94.6.1017. ISSN 0002-9122. PMID 21636471.
Huck, R. B. (2008). Dicerandra modesta (Lamiaceae): Raise in rank for a disjunct perennial in a new coastal clade in Florida.[permanent dead link] J Bot Res Inst Texas 2:2 1163.
Huck, Robin B. (1987). Systematics and Evolution of Dicerandra (Labiatae). Phanerogamarum Monographiae. 19. Schweizerbart. ISBN 978-3-443-78001-2.