The Lindsaeoid ferns of the Old World. I. New Caledonia

The present paper is the first of a series of regional revisions of the Old World Lindsaeoid ferns centering around a revision of the group in the Flora Malesiana area where the largest number of species occurs. In the few cases where modern revisions are already available the present author’s contribution will be limited to critical and additional notes; otherwise they will be in the nature of monographic treatments, although widespread species will, of course, as a rule not be described more than once. The botanically isolated position of New Caledonia is well-known, and most floristic phytogeographers agree in regarding it as a separate floristic region (e.g. Good, 1947; Van Balgooy, 1960). Endemism is high in the ferns as well as in the flowering plants, although the number of endemic fern genera is very small (Brownlie, 1965). In the absence of a comprehensive modern fern flora I am unable to quote any reliable figures. The last paper dealing with the New Caledonian fern flora as a whole by Fournier (1873) is nearly 100 years old. Later contributions were made notably by Copeland (1929b), Christensen (in: Däniker, 1932), and Guillaumin (1962- 1964). Christ (1910), on the basis of Fournier’s (1873) data, reported 259 species, 86 endemic, but stated that Fournier’s species concept was apparently too narrow (p. 234), which I can confirm for the Lindsaea group, as shown by the synonymy in the present paper. On the other hand, additional species have been found or distinguished since. A more important factor limiting our knowledge of endemism in the New Caledonian ferns (and other plants) is, I think, the poor state of knowledge of the Melanesian flora, particularly of the Solomon Islands. The exploration that is now in progress in this archipelago may be expected to furnish important additional data.