Sericocarpus

White-topped Asters

The genus Sericocarpus Nees includes five x=9 species native to North America. Members of the genus are distinguished from other typcial asters by having heads with cylindrical to ovoid involucres with cartilaginous phyllaries and only a few white ray florets and white to creamy disk florets. The chlorophyllous zone on the phyllaries is similar to most Eurybia species. The heads of usually grouped in tight clusters in a flat-topped arrangement. The fruit pappus is usually triple (Leonard et al. 2005).

The genus was recognized as distinct from Aster in the broad sense by Fernald (1950) following older treatments, while Cronquist (1980) included the genus in Aster. Nesom (1993) argued for treating Sericocarpus as a separate genus. Sericocarpus was found to be the sister group to Aster s.s. by Xiang and Semple (1996), but this was an artifact of not including samples of African and South American genera in the RFLP study of cpDNA. Brouillet, Allen, Semple and Ito (2001) found Sericocarpus to be a near basal member of the clade including Solidago, Chrysothamnus, Petradoria and Tonestus and other yellow-rayed Asteraeae of subtribe Solidagininae s.s.

Leonard, Cook & Semple (2005) presented the results of a multivariate morphometric analysis of Sericocarpus and presented a taxonomic treatment with detailed descriptions, detailed illustrations of each species and dot distributions. This was used to prepare the treatment of the genus for Flora North America (Semple & Leonard 2006).

Sericocarpus asteroides (syn: Aster paternus)
Sericocarpus tortifolius (syn: Aster bifoliatus)
Sericocarpus linifolius (syn: Aster solidagineus)
Sericocarpus oregonensis
Sericocarpus rigidus (syn: Aster curtus)

Leonard, M.R, R.E. Cook and J.C. Semple. 2005. A multivariate morphometric study of the aster genus Sericocarpus Nees (Asteraceae: Astereae). Sida 21: 1471-1505.

Semple, J.C. and M.R. Leonard. 2006. Sericocarpus Nees. pp. 101-105. In Flora North America Editorial Committee, eds. Flora of North America. Vol. 20. Asteraceae, Part 2. Astereae and Senecioneae. Oxford University Press, New York.

revised 2 February 2014 by J.C. Semple