Gnidia is probably the largest genus in the family and is almost completely restricted to Africa and Madagascar. It is treated here in the traditional sense, i.e., including Lasiosiphon, Arthrosolen and several other segregates, except for the small Southern African genus Englerodaphne, which is still tentatively maintained for now as distinct.
Beaumont et al. (2009) suggested that Lasiosiphon be removed from synonymy with Gnidia on the basis of rather limited and moderately supported molecular data. Broader taxon sampling including critically important taxa and the addition of more genes will be needed to adequately address generic limits of Gnidia, its segregates, and other groups (e.g., the Australian/Pacific genus Pimelea).
In 2013 two South African authors published a new species in Lasiosiphon and two new Lasiosiphon recombinations for well established Gnidia species, using the very preliminary and inconclusive molecular study of Beaumont et al. (2009) as justification. It is this authors' opinion that others should avoid creating new Lasiosiphon combinations until more compelling phylogenies are published in journals with rigorous editorial and review standards.
For botanists interested in following the more conservative, pragmatic circumscription of Gnidia adopted for A World Checklist of Thymelaeaceae, it is worth pointing out that nearly all recognized taxa (ca. 130 species as of Oct. 2013) belonging to the group already have well-established validly published names in Gnidia.