Acta Botanica Hungarica 31. [antikvár]

Acta Botanica Hungarica 31 (1-4), pp. 3-34 (1985) PHYTOGEOGRAPHIC SURVEY OF CUBA I. THE PHYTOGEOGRAPHIC CHARACTERISTICS AND EVOLUTION OF THE FLORA OF CUBA A. Borhidi institute of ecology and botany, hungarian academy of sciences, 2163 vacrat6t, hungary (Received: 10 October, 1984) Some of the main characteristics of the flora of Cuba are exposed and discussed, as the dominance of endemics, disjunction, vicariancy, inversion, microphyUia, mic-ranthia, relict character and vulnerability. The origin, evolution and presumable migrations of the flora are also discussed, based on the results of the geological up-to-date investigations on the plate tectonics. In the process of the flora evolution three main phases are distinguished, the early plate phase, the middle-tertiary land-bridge phase and the late archipelago phase. As the last important period of the flora immigrations the middle tertiary land-bridge phase is discussed with its different floras, as the broad-leaved Honduras-flora, and the sclerophyllous Madro-Tethyan flora. In the late archipelago phase the broad-leaved Guyana-flora, the semideciduous Yucatan-flora and the extratropical North-American flora influenced the evolution of the flora and vegetation of Cuba. At last the evolution centres of the ecologically and/or phyto-sociologically adapted species groups and their migratory routes are designed and explained. The phytogeographic characteristics of Cuba Some outstanding phytogeographic features of Cuba The floristic analysis and the study of chorological types suggest that the most important and most typical characteristics of the flora of Cuba are as follows: 1. Dominance of endemics, 2. Disjunction, 3. Vicariancy, 4. Inversion, 5. MicrophyUia, 6. Micranthia, 7. Relics, and 8. Vulnerability. The dominance of endemics As shown earlier (Borhidi 1982), the endemics comprise a total of 51.4% of the native flora. This is outstandingly the largest percentage in the Antilles. Marie-Victorin (1942 1944, 1956) attirbuted this to the high Mg and Fe concentrations of "limonite areas". According to Alain's (1958 p. 16) hypothesis, the reasons are the early isolation of the flora during the upper Miocene, the diverse edaphic soil conditions of the country and the arid climate of certain areas. The ecology of endemic speciation In examining the ecological background of the speciation of endemics MuNIZ (1970) found that eight habitat types have substantial influence on flora development. These habitats occur in 25 areas in Cuba. The habitat types with tbe number of areas in brackets are: