Contributo alla conoscenza floristica dei licheni italiani: l'agro di Manduria (Taranto, Italia). Contribution to lichen flora in Italy: the "agro di Manduria" (Taranto, Italy)

In this work there is a first census of the lichen florula of the Manduria countryside, a site that occupies the south-eastern part of the province of Taranto, which has been little explored in the lichenological field today, probably due to the strong agricultural vocation of this land and its high degree of anthropization. However, this territory represents an excellent source of biodiversity, even if the sites of naturalistic interest are now greatly reduced and represent what remains of the ancient spontaneous vegetation called "Foresta Oritana", that until the nineteenth century extended into the upper Salento. Only degraded scrub and gariga of this forest remain, too often subject to fires, and few residual woods, including Bosco Cuturi and Bosco Rosamarina, which are located precisely in the Manduria countryside. These woods are mainly populated by Quercus ilex, but also by typical shrubs of the Mediterranean scrub. The survey on lichen flora was preceded by the collection of bibliographic data present in the literature concerning Salento and integrated with the ecological, taxonomic and distributional information present on ITALIC 5.0 (Nimis and Martellos, 2017); identification was carried out basically in the field and when necessary in the laboratory. The research focused in particular on some of the naturalistic sites of the Manduria countryside (Bosco Cuturi and Bosco Rosamarina), on the scrub and gariga in Contrada Marina and at Monte del Diavolo, as well as in olive groves in the area, examining, photographing and cataloging the lichen populations present on the shrubby and arboreal flora, on the soil and on rocky substrates (outcropping rocks and dry stone walls). The research led to the identification of 68 species, mainly temperate-Mediterranean taxa in accordance with the distributional forecasts for the area falling in the dry Mediterranean belt (Nimis, 2016). In the woods there is a prevalence and wider variety of foliose and fruticose lichens and among these Parmotrema hypoleucinum and Parmotrema pelatum seem to have found their ideal habitat in the holm oaks of Bosco Cuturi and Bosco Rosamarina. However, in the scrub and gariga there is a prevalence on the ground of Cladonia foliacea f. convoluta and Cladonia rangiformis, while crusty forms such as Lecidella elaeochroma and Lecanora chlarotera prevail on shrubs and olive trees, together with the foliose lichens Xanthoria parietina and Physcia adscendens. The lithic substrates are colonized mainly by Verrucaria nigrescens, Variospora aurantia and Xanthocarpia ochracea. Of great importance is the rediscovery of Teloschistes chrysophthalmos, reported for the first and only time in Puglia by Jatta in 1889 and included in the red list of lichens in Italy. It was found on several trees both in the woods and on isolated trees, demonstrating the ecological importance of the site.