Phytosociological research on temporary ponds in Apulia (southern Italy)

The ephemeral hygrophilous vegetation occurring in the temporary ponds of Apulia (southern Italy) were studied following the phytosociological approach. On the base of 153 phytosociological relevés carried out during the period 2015- 2018, 19 associations were identified, of which 16 described for the first time. All the associations belong to the IsoetoNanojuncetea class. The surveyed associations can be arranged in two orders, such as Isoetetalia, including those with a winter-spring cycle and Nanocyperetalia, regarding those with a summertime cycle. The identifed associations have been examined in detail, and for each one, we provided a phytosociological table. The communities belonging to the Isoetetalia are 17 and arranged in four alliances (Isoetion, Preslion cervinae, Cicendio fliformis-Solenopsion laurentiae, Agrostion salmanticae); instead, those ones of Nanocyperetalia are two both included in the Verbenion supinae. In order to highlight the relationships among the associations, all the relevés used for this investigation are processed. Overall, this analysis confirms the autonomy of the associations, grouping them according to the syntaxonomic arrangement proposed by the authors. Taxonomic investigations on the flora occurring in these habitats allowed the detection of two new subspecies of Solenopsis laurentia, both with a different autoecology.