Thallus bushy, hemispherical, 5-14(-20) cm high, cream-red; branching dichotomous; calcification moderate. Blades 1.0-3.0 mm wide, 300-500 µm thick, flat, smooth, often with faint cross banding near apices; margins slightly thickened. Medullary filaments 8-15 µm diam., sparse, intermixed with gelatinous mucilage. Cortex 2-3 cells thick; innermost cells 25-65 µm thick, 50-100 µm wide, lightly pigmented; surface cells of tetrasporangial thalli stalked, oval or spherical, 22-40 µm diam., 30-60 µm long, thick-walled, laterally free, with apex rarely pointed; subsurface cells bearing 1-3 surface cells; surface cells of gametangial thalli narrowly oval or columnar, 10-16 µm diam., 25-45 µm long, with blunt apex; subsurface cells triangular, compressed, colorless, laterally adherent, bearing one surface cell; surface hair-like filaments rare.

Huisman, J.M., Harper, J.T. & Saunders, G.W. (2004). Phylogenetic study of the Nemaliales (Rhodophyta) based on large-subunit ribosomal DNA sequences supports segregation of the Scinaiaceae fam. nov. and resurrection of Dichotomaria Lamarck. Phycological Research 52(3): 224-234.

Huisman, J.M., Sherwood, A.R. & Abbott, I.A. (2004). Studies of Hawaiian Galaxauraceae (Nemaliales, Rhodophyta): Large subunit rDNA gene sequences support conspecificity of Galaxaura rugosa and G. subverticillata. Cryptogamie Algologie 25: 337-352.

Wang, W.-L., Liu, S.-L. & Lin, S.-M. (2005). Systematics of the calcified genera of the Galaxauraceae (Nemaliales, Rhodophyta) with an emphasis on Taiwan species. Journal of Phycology 41: 685-703.

Wynne, M.J. (2005). A check-list of benthic marine algae of the tropical and subtropical western Atlantic: second revision. Beihefte zur Nova Hedwigia 129: 1-152.

Kurihara, A. & Huisman, J.M. (2006). The Dichotomaria marginata assemblage in Australia. In: Algae of Australia Nemaliales. (Huisman, J.M. Eds), pp. 120-122, 134-136. Canberra: Australian Biological Resources Study.

Basionym
Corallina marginata J.Ellis & Solander

Type information
Type locality: Bahamas (Silva, Basson & Moe 1996: 107). Notes: Huisman & Womersley (1994: 115) notes that the type is lost; lectotypified by Ellis & Solander, 1786, pl. 22, fig. 6 (see Papenfuss et al., 1982: 411).