Hi Patrice,
In fact, I have 2 forms of Drosera nidiformis. The first is in all ways similar to the photo posted by Christian: I note the how green this plant is, no matter how much light is given. In full summer sun, the plant turns a golden color with some red glands, but this is only in full strong sun. The general appearance of the plant is green, so I am not surprised at your notation of the white hairs vs. red hairs of the other clone. For a long time, I thought this might be the acaulescent form of D. madagascariensis. My conversations with Robert Gibson confirmed that this is in fact, D. nidiformis.
Part of my confusion was based on the *appearance* of plants grown from seed from the ICPS seedbank. These plants were less robust, but of an over all redder coloration than the above mentioned plant, and conform to what I know of as D. nidiformis.
Taxonomically, they are probably both simply D. nidiformis. Taxonomy cares little about individual variation (such as coloration), and seeks that which unites these variations into a unified whole. In the case of the African species, this is a very difficult task!
One thing which surely sets these 2 species apart is in regards to the scape: D. nidiformis lacks the glandless hairs which are found on D. madagascariensis (the exception being the basal inch or so).
It is entirely likely that there is some introgression in the "sp. Magaliesburg" example. My gut level instincts say it has some involvement with D. natalensis.
D. nidiformis has been the cause of much taxonomic disention, with some authors claiming that the species is no more than a variation of D. dielsiana (supported by the fact that a cross of both species produces fertile seed!
Also keep in mind the distinction between D. dielsiana and D. natalensis is not as black and white as Exel and Laundon suggest in their description. What we are dealing with in African Drosera species is a "complex" where phenotypic expression is virtually unlimited by genetic restrictions between the supposed "species" i.e. D. natalensis, dielsiana and nidiformis. In such a "melting pot" we must be very careful about the criteria that grants species status. It is simply not enough to note that two plants look different, and to conclude that they must therefore be different species.