In order to improve the floristic knowledge of the Italian territory, we report the inventory of the taxa collected during the annual field trip of the working group for Floristics, Systematics and Evolution of the Italian Botanical Society held in 2015 in eastern Irpinia and Vulture-Melfese area (South Italy). The investigated territories are located in southern Apennines, along the border between the Campania and Basilicata administrative regions. These areas are scarcely known in terms of vascular flora. The floristic samplings were performed in 19 sites selected as representative of the local environmental diversity as regards to climate, litho-morphology and land-use.

The research led to the identification of 4,137 specimens of vascular plants, belonging to 815 species and subspecies, 399 genera, and 85 families. Among these taxa, 42 were endemic to Italy, 38 were included in the IUCN Red List of the Italian Flora, 28 were alien and 5 were cryptogenic in Campania and/or Basilicata administrative regions. Two taxa, Aquilegia coerulea (casual alien, native to North America) and Lolium × boucheanum (native), were found to be new for Italy. On the basis of the available floristic literature the first one is also to be considered new for the European flora. At regional scale, we have found 18 taxa new for the Campania and 15 new for the Basilicata region. Finally, 10 taxa were confirmed for Campania. Data obtained during this study, confirmed the important role of a collaborative approach among botanists and the great relevance of these territories for plant diversity.

alien species, botanists, endemics, herbaria, Italian vascular flora, new floristic records, plant diversity, southern Apennines

The floristic knowledge of a territory is of considerable importance for scientific purposes and for conservation (Carli et al. 2018). In particular, the information concerning the endemic plants, such as their distribution and threats, are key elements for driving national conservation strategies (Brundu et al. 2017, Orsenigo et al. 2018). Wild vascular plants were recently used in some areas of Central-South Italy to evaluate the long-term changes in the floristic composition of vegetation of mountain ecosystems (Calabrese et al. 2018, Frate et al. 2018) and for risk assessment and management of soils polluted by industrial processes (Visconti et al. 2018). In the last two decades, the activities of the working group for Floristics, Systematics and Evolution of the Italian Botanical Society have greatly improved the knowledge about the vascular flora of some scarcely known areas of the Italian territory by using a collaborative approach (Peccenini et al. 2007, 2010, Peruzzi et al. 2011, Bouvet et al. 2018, Bartolucci et al. 2019a). This has been particularly fruitful in the southern part of Italian Peninsula (Conti et al. 2006, 2007, Santangelo et al. 2010, Bernardo et al. 2012, Wagensommer et al. 2014, Domina et al. 2015, Rosati et al. 2017, in press). Herein, we present the results of the floristic field excursion held in 2015 in eastern Irpinia and Vulture-Melfese area in southern Apennines (Italy). This research aims at improving the floristic knowledge of these areas which are located at the boundary between the administrative regions of Basilicata and Campania. According to Scoppola and Blasi (2005) and Blasi et al. (2011) these areas were included among those for which the available floristic data were absent or particularly scarce.

After the research, 4,137 specimens of vascular plants were identified, including 6 Orchidaceae documented only by digital photographs. These were classified in 814 species and subspecies, belonging to 399 genera and 85 families (Suppl. material 1: S7 and S8), together with 4 hybrids (Crataegus × media Bech., Lolium × boucheanum Kunth, Medicago × varia Martyn and Vitis × koberi Ardenghi, Galasso, Banfi & Lastrucci), and 1 cultivar of Viola tricolor L. subsp. tricolor.

Forty-two taxa (5.2% of the total flora detected, Table 1) were found to be endemic to Italy (Peruzzi et al. 2014, 2015, Bartolucci et al. 2018), while 28 taxa (3.4%) were found to be alien for the study area (Bartolucci et al. 2018a, Galasso et al. 2018a).

Five taxa (0.6% of the total flora), Brassica nigra (L.) W.D.J.Koch, Gladiolus italicus Mill., Melissa officinalis L. subsp. officinalis, Oxalis corniculata L. and Papaver rhoeas L. subsp. rhoeas, were considered cryptogenic in the investigated area (Bartolucci et al. 2018a, Galasso et al. 2018a).

Forty-three units (5.3% of the total flora) were found to be new floristic records. In particular, Aquilegia coerulea E.James (casual alien) and Lolium × boucheanum Kunth (native) are recorded for the first time in Italy.

As reported below, 18 and 15 taxa were found to be new for the regional flora of Campania (Table 2) and Basilicata (Table 3), respectively.

This research also allowed to confirm 10 taxa for the flora of Campania (Table 4).

Data obtained shows that the eastern Irpinia and Vulture-Melfese area hosts a rich and interesting vascular flora. Except for Aristolochia clusii, Digitalis micrantha, Ononis oligophylla and Ophrys tenthredinifera subsp. neglecta, all the other Italian endemic taxa recorded are currently included in the IUCN Red List of the Italian Flora (Rossi et al. 2013, Orsenigo et al. 2018) together with the non-endemic Orchis provincialis Balb. ex Lam. & DC. (38 taxa, 4.7% of the total flora). As regards Thymus picentinus, the specimens collected during this study allowed Bartolucci and Mráz (2016) to confirm the occurrence of this taxon in Basilicata and to re-evaluate its taxonomic status.

Among the non-native plants, 18 taxa were neophyte and 8 were considered invasive in at least one of the administrative regions considered (Ailanthus altissima, Amaranthus retroflexus, Crepis sancta subsp. nemausensis, Dysphania ambrosioides, Erigeron sumatrensis, Paspalum distichum, Robinia pseudoacacia and Veronica persica).

A small population of Aquilegia coerulea, a neophyte native to North America (Whittemore 1997), was found in Aquilonia (Campania, Avellino province) in anthropogenic environments. These individuals much likely derived from nearby cultivated plants seeds. Based on our floristic literature research (e.g., Nardi 2017), this record is the first for the European flora. Lolium × boucheanum, that is the natural hybrid between Lolium perenne L. and L. multiflorum Lam., it was collected in a marginal area of Monteverde (Campania, Avellino province) and is reported for the first time in Italy. As far as Bromus hordeaceus subsp. longipedicellatus, before this study its Italian distribution was restricted to Lombardia and Sardegna (Bartolucci et al. 2018a). Our findings of this taxon in Campania and Basilicata (Table 2 and Table 3) are therefore to be considered the first records for the peninsular Italy. Likewise, the discovery of Medicago glutinosa in Campania (Table 2) confirms its presence in southern Italy. Indeed, this species was reported only for Lombardia, Veneto, Liguria and Toscana, while was no longer recorded for Emilia-Romagna, and is considered doubtful in Umbria, Marche and Calabria (Bartolucci et al. 2018a).

Saxifraga stolonifera too is currently recorded in Lombardia and Veneto, while it is no longer recorded in Liguria (Galasso et al. 2018a). Therefore, our record from Basilicata (Table 3) is the first for the peninsular Italy.

In addition to the 11 taxa that we confirmed for Campania (Table 4), the observations made during this study also allowed Scoppola et al. (2016) to confirm the presence of Trifolium multistriatum W.D.J.Koch for the same region.

Some of the specimens collected in the study area require additional investigations aimed to clarify their taxonomic status. For example, the complex of Centaurea deusta shows a considerable variability in Italy (Stinca et al. 2019a). The samples found are probably attributable to a new taxon under study.

In recent years, especially in Campania, some researchers have focused their attention on the territories that are not well known from a floristic point of view, such as the lowlands and urbanized areas (e.g., Stinca et al. 2016, 2017a, Motti et al. 2018, Croce et al. 2019, Stinca 2019, Stinca and Mei in press). Some studies were carried out also in well-known areas from a floristic point of view, that have allowed to update their flora (e.g., Rosati et al. 2012, Stinca and Motti 2013, Stinca et al. 2014, 2017b, 2019b, Salerno and Stinca 2017, Stinca 2017). The floristic exploration of eastern Irpinia and Vulture-Melfese area, although carried out in a few days and in a limited number of sampling localities, allowed recording a considerable amount of taxa. The high number of species of floristic interest found, as well as the numerous floristic novelties suggest a high biodiversity level of the eastern Irpinia and Vulture-Melfese area, which are areas poorly studied by botanists in the past but that deserve further research.

We are very grateful to: E. Banfi, L. Cecchi, G. Domina, G. Gottschlich and E. Nardi for the revisions of critical specimes; M. Lorito, N. Madonna and S. Mazzoleni for hosting the workshop held at Portici in the Library of Agriculture and Department of Agricultural Sciences of the University of Naples Federico II; R. Motti and R. Spicciarelli for guiding us in the Botanical Garden of Portici and Grotticelle Oriented Nature Reserve of Rionero in Vulture, respectively; A. Ferretti, U. Silvestri, A.G. Stinca and C. Verdoliva for their assistance during the workshop held at Portici; P. Di Gala for the kind hospitality at the Hotel Ristorante “Lo Smeraldo” in Aquilonia.