D. romana was first described from Italy in 1813 and its name unsurprisingly means Roman Orchid. It is a widespread species living primarily in the central and eastern areas of the Mediterranean, but reaching as far east as Bulgaria and Russia.
It may be found in many types of habitat but shows a marked preference for woodland, often heavily shaded. Although not exclusively a montane orchid, it appears to prefer higher altitudes, being perfectly happy with mountain existence up to altitudes of 2000m. The very similar D. markusii seems to prefer more heavily acidic conditions and even higher altitudes. Perhaps the one species that may cause cunfusion with this white variety of D. romana is O. provincialis, though this can usually be differentiated by its dark spotted leaves, smaller bracts and red markings on the lip. D. romana occurs in yellow, red and much the rarest, white forms which may all be present within the same population. Intermediates between the colour phases are common.

The white form of D. romana is rare but most frequently found as the dominant colour where it occurs and is rarely encountered in mixed colour populations. This does not infer any evolutionary development away from type, rather that white flowers generally experience higher levels of pollination due to their increased conspicuousness to pollinators. 

The pictures are from Lesbos, Cilento and Samos dating from early April.