"Vegetatively, at least in N.Z., specimens here attributed to C. apetalus and C. affinis are often indistinguishable, although they differ constantly in shape and relative size of sepals. C. affinis has the more restricted distribution here, mostly in high rainfall areas. These two spp. were for a long time included under C. billardieri Fenzl (Ann. Wien Mus. 1, 1836, 49), a name which was nomenclaturally superfluous when published, since both Sagina crassifolia D'Urv. and Spergula apetala Labill. were quoted as synonyms" (Allan 1961).
NZOR Concept Id
NZFLORA (2012-) New Zealand Plant Names - Name based concepts
de Lange, P.J.; Rolfe, J.R.; Champion, P.D.; Courtney, S.P.; Heenan, P.B.; Barkla, J.W.; Cameron, E.K.; Norton, D.A.; Hitchmough, R.A. 2013: Conservation status of New Zealand indigenous vascular plants, 2012. New Zealand Threat Classification Series 3. Department of Conservation, Wellington.