A new species description offers the chance to clarify open questions while studying the alpine Nigritella flora: In the latest edition of the Journal of European Orchids (1/2010), Wolfram Foelsche describes a broad spectrum of doubtful cases where Nigritella plants have been identified as Nigritella rubra without showing the characteristics of this plant as it was described by Richard Wettstein in 1889. With Nigritella rubra sepals and petals should have about the same width. But many plants identified as Nigritella rubra have petals which are considerably slimmer than the sepals. Additionally there are also differences regarding the form of the lip and the colour of the inflorescence: In most cases the plant now described as Nigritella bicolor shows a brighter red in the lower part of the inflorescence than in its upper part. And Nigritella bicolor has a longer spur than Nigritella rubra.
“With its striking inflorescence – above a rim with brightly shining rays the rows of rose-coloured flowers are displayed while the tips of bracts are set apart in dark-red – this new species, without doubt, is our splendid, most attractive nigritella”, Foelsche writes. According to his studies the majority of the photos used to illustrate Nigritella rubra are actually showing Nigritella bicolor which has a much larger area of distribution. Foelsche notes that the bicolour characteristics may be more or less strongly developed. It’s not possible to confound Nigritella bicolor with colour varieties of Nigritella rhellicani with its open labellum: