Cyclamen is an Old World genus with probably 22 species, distributed in Europe and further east to Iran and south to northeastern Africa (Mabberley 2008). None is native to Belgium. All species except one are cultivated as ornamentals, indoors (especially plants derived from Cyclamen persicum Mill.) as well as out-of-doors. Particularly useful accounts for the genus in cultivation in Europe are provided by Grey-Wilson & Maxwell (1997), Jäger & al. (2008) and Grey-Wilson (2015).
The phylogenetic position of Cyclamen has not been resolved yet. It was traditionally placed in Primulaceae but Ståhl & Anderberg (2004) included it in Myrsinaceae because it shares developmental anatomy, leaf pigmentation, and other features with that family. The genus is obviously without close relatives and bears characters that are abnormal in both Primulaceae and Myrsinaceae, e.g. tuberous roots. Our understanding of the family is clearly still in flux, and future taxonomic realignments at the familial and generic levels are to be expected.
Additional interesting information on the genus Cyclamen, including a very extensive bibliography and an identification key, is provided by the Cyclamen Society at: http://www.cyclamen.org.
Cyclamen is very poorly documented in Belgium. Two species have been reliably recorded so far but more may be present. The exact identity of every single population should be critically reassessed.
1 Corolla auriculate at base, each lobe with a purple-magenta V-shaped spot. Flowering in late summer and autumn. Leaves variable but usually lobed or angled, longer than wide === Cyclamen hederifolium
Corolla without auricles at base, each lobe with magenta or purple spot surrounding a paler ‘eye’. Flowering in winter and spring. Leaves circular or kidney-shaped, as long as wide or wider than long, almost entire === C. coum
Anderberg A.A. (1994) Phylogeny and subgeneric classification of Cyclamen L. (Primulaceae). Kew Bulletin 49: 455-467.
Bailey R.H. (1993) A rare and little known book: Monographie du genre Cyclamen by Nestor Seghers. Arch. Nat. Hist. 20: 31-36.
Bennett S.T. & Grimshaw J.M. (1991) Cytological studies in Cyclamen subg. Cyclamen (Primulaceae). Pl. Syst. Evol. 176: 135-143.
Clennett J.C.B. (2002) An analysis and revision of Cyclamen L. with emphasis on subgenus Gyrophoebe O. Schwarz. Bot. J. Linn. Soc. 138(4): 473-481.
Clennett C. (2004) A review of research on Cyclamen. Herbertia 57: 25-35.
Clennett C. (2004) Classification changes in cyclamen - a guide for the grower. Cyclamen 28(1): 10-11.
Compton J.A., Clennet J.C.B. & Culham A. (2004) Nomenclature in the dock. Overclassification leads to instability: a case study in the horticulturally important genus Cyclamen (Myrsinaceae). Botanical Journal of the Linnean Society 146(3): 339-349.
Grey-Wilson C. & Maxwell H.S. (1997) Cyclamen. In: Cullen J. & al. (eds.), The European Garden Flora, vol. 5. Cambridge University Press, Cambridge: 549-555.
Grey-Wilson C. (2015) Cyclamen: A Guide for Gardeners, Horticulturists and Botanists. Batsford, London: 196 p. [available on line, pro parte: https://books.google.be/books?id=H0O_CAAAQBAJ&pg=PA40&lpg=PA40&dq=cyclamen+kew+bulletin+1994&source=bl&ots=XEdi7UX4AU&sig=l5jNuGgLsDK15yRTfFmdWaaY5zE&hl=en&sa=X&ei=iBydVdXcDcyBUaSwg6AL&ved=0CCQQ6AEwAA#v=onepage&q=cyclamen%20kew%20bulletin%201994&f=false]
Hildebrand F. (1999) The genus Cyclamen L.: a systematic and biological monograph. London, The Cyclamen Society: 126 p.
Ietswaart J.H. (2005) A review of species limits in Cyclamen L. (Primulaceae). Cyclamen 29: 18-23.
Jäger E.J., Ebel F., Hanelt P. & Müller G. (eds.) (2008) Rothmaler Band 5. Exkursionsflora von Deutschland. Krautige Zier- und Nutzpflanzen. Springer Verlag, Berlin: 880 p.
Mabberley D.J. (2008) Mabberley’s plant-book (3th ed.). Cambridge University Press, Cambridge: XVIII + 1021 p.
Schwarz O. (1955) Systematische Monographie der Gattung Cyclamen L. Feddes Repertorium Specierum novarum regni vegetabilis 58: 234-283.
Schwarz O (1964) Systematische Monographie der Gattung Cyclamen L. Feddes Repertorium 69: 71-103.
Stace C. (2010) New flora of the British Isles, 3th ed.: XXXII + 1232 p. Cambridge University Press.
Ståhl B. & Anderberg A.A. (2004) Myrsinaceae. In: Kubitzki K. & al. (eds.) The Families and Genera of Vascular Plants, vol. 6: 266-281.