Monographs Details: Brunellia sibundoya subsp. sebastopola Cuatrec.
Authority: Cuatrecasas, José. 1985. Brunelliaceae (supplement). Fl. Neotrop. Monogr. 2: 28-103. (Published by NYBG Press)
Family:Brunelliaceae
Discussion:Remarks (Fig. 11). When B. sibundoya was first published in 1942, its differences from B. comocladifolia H. & B. seemed clear, especially when compared with the typical form, subspecies comocladifolia. Years later, considering the broad polymorphism of the latter species throughout its extensive area, its differentiation from B. sibundoya has become more difficult. The discovery of populations of B. sibundoya distant from its original area added to the difficulties. However the study of some variations observed in both species resulted in the description of subspecific taxa relatively consistent within their geographical areas (Cuatrecasas, 1970, pp. 63, 80).

Once the subcategories were established, no great difficulties were found in the identification of recent collections, except for those coming from an area where B. comocladifolia and B. sibundoya are apparently sympatric. In Colombia, B. sibundoya seems to be found at higher elevations in the upper Andean forest than B. comocladifolia, which occurs in an adjacent zone of lower elevation. There is the possibility that cross-pollination occurs between the two species in the ecotone. Collections ascribed to B. comocladifolia subsp, cundinamarcensis and B. sibundoya subsp, sebastopola are the most difficult to distinguish. They might both be of hybrid origin between B. comocladifolia and B. sibundoya in the ecotonic area of Cundinamarca. One major difficulty in defining limits for B. sibundoya and the whole B. comocladifolia complex, respectively, lies in the fact that several of the subspecies of the latter have some features similar to the former. Subsp. jamaicensis and subsp, domingensis, although isolated in faraway islands, have traits similar to B. sibundoya, e.g., the broader, larger, sessile leaflets, more abundant indument, and probably larger flowers. In addition they have type II pollen grains, with verruculose sexine, in contrast with the pollen grains of typical B. comocladifolia which are of type I, with reticulate sexine (Cuatrecasas, 1970, p. 27).

In the past I have considered B. comocladifolia a "good" widespread species with archipelago-type distribution in spite of its variations. Similarities like the ones mentioned above can well be explained as produced by parallel evolution. On the other hand, B. sibundoya, although clearly defined and consistently characterized in its area, could be viewed as an extreme product of the evolution of B. comocladifolia, adapted to a higher elevation.

The clarification and delimitation of the taxa involved within the B. comocladifolia complex and its connections to B. sibundoya will have to be done on the basis of extended field and laboratory work with natural populations of every subspecies. Such a study should cover all morphological aspects of all significant parts of the plants in every population.
Distribution:Colombia South America| Cundinamarca Colombia South America|