Stazioni di roccia a Monte S. Nicola (Monopoli, Puglia) con osservazioni suix'areale di Campanula Versicolor sib. et sm., Carum Multiflorum Boiss. e Scrophularia lucida L

Abstract

SOME ROCK HABITATS NEAR MONOPOLI (APULIA), WITH NOTES ON THE AREA OF DISTRIBUTION OF CAMPANULA VERSICOLOR SIB. ET SM., CARUM MULTIFLORUM BOISS., and SCROPHULARIA LUCIDA L. — At Monte San Nicola, near Monopoli (Apulia), half way up a steep slope at ca. 200 m. o. s. I., some vertical limestone rocks harbour a saxatile community which includes some species more or less rare in Apulia.

Three of these species, Campanula versicolor Sib. et Sm., Carum multiflorum Boiss., and Scrophularia lucida L., have a mainly Greek distribution and, to the west of the Adriatic sea, they have only been reported for southern Apulia. C. versicolor is mainly found on the mountains of the Greek mainland and Albania; it occurs on a few of the Jonian islands. Its typical habitats are the crevices of shady vertical rocks. C. multiflorum is reported for several mountainso n the Greek mainland but also on a number of islands including Crete and Cyprus; its typical habitats are rock crevices. S. lucida is a mainly coastal species found on a great number of the Aegean and Jonian islands; it grows on rocks and walls.

These data can explain the differences in the geographic distribution and ecology of these species inside Apulia. While Scrophularia is to be found mainly along the coast from Gallipoli to Santa Maria di Leuca, Otranto and as far north as Bari, Campanula is present on the high cliffs of the extreme Salento and in a series of localities on the southern slopes of the Murge. Carum has been found mostly in this latter type of stations, but is extremely rare. Both groups of stations are included in a vegetational belt corresponding roughly to the Quercus ilex belt. At Monte San Nicola itself there is a definite pattern of distribution on the rock habitats, Campanula colonising only the very well shaded vertical rock faces, Carum those slightly less shaded, while Scrophularia is fairly abundant on vertical or sloping rocks with various degrees of insolation.

Taking into account their general behaviour in Apulia and the fact that they do not practically occur to the north of a line going from Monopoli to Matera, south of which the Apulian flora shows a high degree of «hellencity», these three species can be grouped with the Southern Palaeoaegeic Transionian ones (GRIDELLI, 1950). The geographic distribution of these species dates back to the middle Miocene when the southern «Aegeis» included the Apulian region south of the Foggia plain.