In this contribution, new data concerning the distribution of vascular flora alien to Italy are presented. It includes new records, confirmations, and status changes for Italy or for Italian administrative regions. Nomenclatural and distribution updates, published elsewhere, and corrections are provided as Suppl. material 1.

Alien species, floristic data, Italy, nomenclature

The text for the new records should be submitted electronically to Lorenzo Lastrucci (lorenzo.lastrucci@unifi.it). The corresponding specimen along with its scan or photograph has to be sent to FI Herbarium: Museo di Storia Naturale (Botanica), Sistema Museale di Ateneo, Via G. La Pira 4, 50121 Firenze (Italy). Those texts concerning nomenclatural novelties (typifications only for accepted names), exclusions, and confirmations should be submitted electronically to Gabriele Galasso (gabriele.galasso@comune.milano.it). Each text should be within 1,000 characters (spaces included).

Abies nordmanniana (Steven) Spach subsp. nordmanniana (Pinaceae)

+ (CAS) TAA: Trento (Trento), fraz. Meano (WGS84: 46.133649°N, 11.124639°E), radura boschiva di un bosco termofilo a roverella, 455 m, 17 October 2021, G. Bonari (FI). – Casual alien species new for the flora of Trentino-Alto Adige.

This species occurs with an individual in a thermophilous oak forest of Adige Valley. The other herbarium specimens from bottom-valley sites testify for the use of this species in afforestation since many years and support the limited spread of this species at sites [e.g., Ala (Trento), fraz. Serravalle all’Adige, sentiero per loc. Fortini (WGS84: 45.815032°N, 11.018794°E), esemplari sparsi (piantati) nel bosco di pino nero, 400 m, 7 January 2005, leg. F. Prosser sub Abies cephalonica, rev. F. Prosser 2021 (ROV)]. Furthermore, this species is cultivated as Christmas tree in Val Sugana (G. Bonari pers. obs.) and sometimes planted in gardens (e.g., in Calamento valley, G. Bonari pers. obs.). This species can be distinguished from similar ones for having non-resinous buds, glabrous branches and non-prickly needles.

G. Bonari, F. Prosser

Acacia dealbata Link (Fabaceae)

+ (NAT) UMB: Orvieto (Terni), loc. Tordimonte, lungo la strada SP98 (WGS84: 42.682246°N, 12.193114°E), margine stradale, 314 m, 20 February 2022, leg. M. Mugnai, M. Vinci, det. M. Mugnai, L. Lazzaro, G. Ferretti (FI). – Naturalized alien species new for the flora of Umbria.

Several adult individuals along the provincial road originated from seeds produced by nearby trees. We observed a substantial spreading of the species with individuals at different growth stages occurring along the road.

M. Mugnai, L. Lazzaro

Acacia pycnantha Benth. (Fabaceae)

+ (INV) SAR. – Status change from naturalized to invasive alien for the flora of Sardegna.

Acacia pycnantha was commonly used for afforestation and reforestation in Sardegna. Although less common in coastal areas, this species is showing similar invasive behavior to A. saligna (Labill.) H.L.Wendl. in several inland areas (up to ca. 500 m a.s.l.) but also in a few sites along the coast (e.g., at the edges of a Pinus plantation, WGS84: 40.466866°N, 9.775060°E).

M. Fois, A. Cuena-Lombraña, G. Brundu, V. Lozano

Achillea filipendulina Lam. (Asteraceae)

+ (CAS) SAR: Capoterra (Cagliari), Rio Santa Lucia (WGS84: 39.1702743°N, 8.9973075°E), banco fluviale, 3 m, 5 July 2022, A.P. Lecis, L. Podda, A. Lallai (FI, CAG). – Casual alien species new for the flora of Sardegna.

A group of four flowering individuals was found along the riverbank, probably originated from seeds of plants growing nearby.

A.P. Lecis, L. Podda, A. Lallai

Amaranthus viridis L. (Amaranthaceae)

+ (CAS) MOL: Isernia (Isernia), Via J.F. Kennedy 92 (WGS84: 41.59408°N, 14.23302°E), margine stradale, 463 m, 29 July 2021, leg. A. Hussain, det. A. Hussain, P. Fortini, D. Iamonico (FI, IS No. IS-1003, RO). – Casual alien species new for the flora of Molise.

A few individuals were found.

A.N. Hussain, P. Fortini, D. Iamonico

Anethum graveolens L. (Apiaceae)

+ (CAS) PUG: Rocchetta Sant’Antonio (Foggia), loc. Santuario della Madonna del Pozzo (WGS84: 41.091227°N, 15.444830°E), margine stradale/coltivi, 452 m, 6 July 2022, G. Buccomino (FI). – Casual alien species new for the flora of Puglia.

G. Buccomino

Bignonia capreolata L. (Bignoniaceae)

+ (CAS) ITALIA (LOM): Milano (Milano), piazza d’Armi, tra Via delle Forze Armate, Via della Rovere e Via G. Mazzarino (WGS84: 45.462558°N, 9.118055°E), margine incolto, 124 m, no exp., 24 May 2022, leg. G. Galasso, R. Gentili, L.A. Quaglini, det. G. Galasso (FI, MSNM barcode MSNM51826). – Casual alien species new for the flora of Italy (Lombardia).

Bignonia capreolata is a species native to SE-North America (Britton and Brown 1913). One sterile individual was found.

G. Galasso, R. Gentili, L.A. Quaglini

Broussonetia papyrifera (L.) Vent. (Moraceae)

+ (INV) LAZ. – Status change from naturalized to invasive alien for the flora of Lazio.

In Ferentino (Frosinone), we found several sites where this species is widespread and colonizes ruderal areas and abandoned fields, even forming dense thickets (e.g., WGS84: 41.679429°N, 13.256788°E; 41.704276°N, 13.265966°E; 41.689602°N, 13.256781°E). We therefore propose its status change from naturalized to invasive alien.

E. Fanfarillo, T. Fiaschi

Campanula portenschlagiana Schult. (Campanulaceae)

+ (CAS) LAZ: Jenne (Roma), centro storico (WGS84: 41.886577°N, 13.168036°E), vecchi muri, 815 m, 15 November 2021, leg. L. Rosati, det. L. Rosati, L. Cancellieri (FI). – Casual alien species new for the flora of Lazio.

L. Rosati, L. Cancellieri

Cenchrus clandestinus (Hochst. ex Chiov.) Morrone (Poaceae)

+ (CAS) ITALIA (CAL): Catanzaro (Catanzaro), Parco della Biodiversità Mediterranea (WGS84: 38.922443°N, 16.580986°E), muro di contenimento in cemento da cui fuoriesce una perdita d’acqua, 404 m, 18 March 2022, A. Capuano (FI). – Casual alien species new for the flora of Italy (Calabria).

This species, identified according to Maire (1952) and Wipff (2003), has been used to create a small lawn in a nearby area. Cenchrus clandestinus is native to humid highlands of central and eastern Africa. It has been introduced as pasture and ornamental grass to temperate and subtropical regions of America and Australia, where it shows adaptations to different environmental conditions (Fraser et al. 2017). It usually reproduces by vegetative propagation by rhizomes (Arango Gaviria et al. 2019).

A. Capuano

Centaurea diluta Aiton (Asteraceae)

+ (NAT) PUG: Gravina (Bari), agro di Gravina, al bordo del vulcanello (WGS84: 40.702861°N, 16.429033°E), incolto, 210 m, 27 April 2022, M. Terzi, F.S. D’Amico (FI). – Naturalized alien species new for the flora of Puglia.

Centaurea diluta is present along an uncultivated strip, near the border between Puglia and Basilicata. This species was also found close to the border on the Basilicata side (Galasso et al. 2021).

M. Terzi, F.S. D’Amico

Chloris gayana Kunth (Poaceae)

+ (CAS) CAL: Catanzaro (Catanzaro), Parco della Biodiversità Mediterranea (WGS84: 38.920250°N, 16.581116°E), pendio erboso incolto, 403 m, 16 February 2022, A. Capuano (FI). – Casual alien species new for the flora of Calabria.

The few observed individuals have been uprooted in order to prevent a future colonisation.

A. Capuano

Chrysanthemum morifolium (Ramat.) Hemsl. (Asteraceae)

+ (CAS) ITALIA (VEN): Verona (Verona), presso la città di Verona in Lungadige Cangrande, lungo la sponda dell’Adige, tra il fiume e l’argine murato (WGS84: 45.44243142°N, 10.98234527°E), sponda erbosa periodicamente inondata, un esemplare in fiore ben radicato nel terreno, 51 m, 15 December 2021, leg. F. Menini, det. F. Menini, G. Galasso (FI). – Casual alien species new for the flora of Italy (Veneto).

This species was reported as alien by several authors (Goiran 1900; Puccini 1950), but only cultivated or escaped within gardens (Galasso et al. 2018).

F. Menini, G. Galasso

Cornus sericea L. subsp. sericea (Cornaceae)

+ (CAS) VEN: Roana (Vicenza), fraz. Camporovere, imbocco sentiero boschivo per il Tanzerloch (WGS84: 45.882409°N, 11.475303°E), margine boschivo al limitare di prato da sfalcio, 1030 m, 24 August 2022, S. Tasinazzo (FI). – Casual alien species new for the flora of Veneto.

A surface of 2 m² was occupied by a clump of non blooming individuals, already observed in August 2021.

S. Tasinazzo

Dysphania pumilio (R.Br.) Mosyakin & Clemants (Amaranthaceae)

+ (NAT) VEN: Chioggia (Venezia), Ca’ Lino (WGS84: 45.162913°N, 12.298620°E), orto, -1 m, 30 October 2021, S. Tasinazzo (FI); ibidem, Ca’ Zadra (WGS84: 45.152445°N, 12.296484°E), coltivo, -1 m, 30 October 2021, S. Tasinazzo (Herb. S. Tasinazzo); ibidem, 26 September 2022, S. Tasinazzo (Herb. S. Tasinazzo). – Naturalized alien species new for the flora of Veneto.

S. Tasinazzo

Ehrharta erecta Lam. (Poaceae)

+ (CAS) CAL: Catanzaro (Catanzaro), Parco della Biodiversità Mediterranea (WGS84: 38.918430°N, 16.580912°E), dentro alcune siepi e aiuole in posizione semiombreggiata, ca. 388 m, 10 February 2022, A. Capuano (FI); ibidem, Via Piave (WGS84: 38.913589°N, 16.585429°E), lungo il marciapiede, nelle aiuole sotto alcuni alberi e in un giardino incolto, 352 m, 2 August 2022, A.Capuano (FI). – Casual alien species new for the flora of Calabria.

Several individuals were observed.

A. Capuano

Eragrostis pectinacea (Michx.) Nees (Poaceae)

+ (NAT) CAL: Santa Sofia d’Epiro (Cosenza), loc. Faudano, nei pressi del Fiume Crati (destra idrografica) (WGS84: 39.589711°N, 16.264669°E), fossato e ambiente umido a margine strada, 70 m, 17 July 2012, leg. L. Bernardo, A. Soldano, D. Puntillo, det. F. Verloove (FI, CLU No. 26304, Herb. A. Soldano No. 16014). – Naturalized alien species new for the flora of Calabria.

A. Soldano, L. Bernardo, F. Verloove

Erythranthe guttata (DC.) G.L.Nesom (Phrymaceae)

+ (CAS) VEN: Zevio (Verona), loc. Ponte Perez, lungo la sponda destra del Fiume Adige (WGS84: 45.37996092°N, 11.13532127°E), greto ghiaioso/sabbioso del fiume, un esemplare in antesi, 27 m, 24 May 2022, F. Menini (FI); Belfiore (Verona), loc. Lorosi, lungo la sponda sinistra del Fiume Adige (WGS84: 45.37091748°N, 11.18414264°E), greto ghiaioso/sabbioso del fiume, 27 m, 24 June 2022, F. Menini (VER); Verona (Verona), loc. Porto San Pancrazio, lungo la sponda destra del Fiume Adige (WGS84: 45.42776403°N, 11.01548551°E), sponda melmosa del fiume, 46 m, 28 June 2022, F. Menini (VER). – Casual alien species new for the flora of Veneto.

F. Menini, S. Andreatta

Eschscholzia californica Cham. subsp. californica (Papaveraceae)

+ (CAS) BAS: Lauria (Potenza), fraz. Pecorone (WGS84: 40.072333°N, 15.857557°E), bordo strada, 778 m, 18 June 2020, leg. A. Montesano (FI). – Casual alien species new for the flora of Basilicata.

A. Montesano, S. Fascetti, L. Rosati

Fatoua villosa (Thunb.) Nakai (Moraceae)

+ (CAS) ITALIA (SAR): Pula (Cagliari), fraz. Santa Margherita di Pula (WGS84: 38.968344°N, 8.965075°E), aree marginali nei pressi di serre e vivai, 15 m, 17 June 2022, G. Bacchetta, G. Loi, G. Calvia (FI, CAG). – Casual alien species new for the flora of Italy (Sardegna).

Fatoua villosa is an annual herb native to East Asia, Pacific islands, and Australia (Zhekun and Gilbert 2003) and reported for Europe only in Corsica (Puddu et al. 2016). A few individuals have been observed.

G. Bacchetta, G. Loi, G. Calvia

Graptopetalum paraguayense (N.E.Br.) Walther subsp. paraguayense (Crassulaceae)

+ (CAS) LAZ: Sant’Angelo Romano (Roma), Via Roma all’altezza del civico 82/a (WGS84: 42.036886°N, 12.714044°E), parete calcarea sul bordo della strada, 350 m, 18 January 2022, M. Giardini (FI). – Casual alien species new for the flora of Lazio.

In Sant’Angelo Romano, at least three luxuriant individuals grow spontaneously on a limestone wall, probably originated from specimens cultivated in the balconies above. Similarly, it is possible to explain the presence of Sedum palmeri S.Watson and Aloë maculata All. subsp. maculata in the same site.

M. Giardini

Hertia cheirifolia (L.) Kuntze (Asteraceae)

+ (CAS) ITALIA (LOM): Bergamo (Bergamo), Via San Martino della Pigrizia, muro sul lato NW (WGS84: 45.702992°N, 9.648287°E), muro, 331 m, SE, 27 February 2022, E. Banfi (FI, MSNM barcode MSNM51577). – Casual alien species new for the flora of Italy (Lombardia).

A description of the plant is given by Iamonico and El Mokni (2021) along with the species’ typification. It is native to Algeria and Tunisia and, since a few decades, it is the object of floricultural trade at least in Bergamo, where attempts at cultivation in flowerbeds in the Lower City have not had the same success as the plant growing spontaneously on the wall of the Upper City (Luca Mangili, pers. comm.).

E.Banfi, G. Galasso

Honorius nutans (L.) Gray (Asparagaceae)

+ (CAS) TOS: Cavriglia (Arezzo), lungo strada SP408 di Montevarchi tra C. Olivacci e Tribolino (WGS84: 43.509780°N, 11.481830°E), margine di querceto ceduo, 100 m, 26 March 2022, L. Pinzani (FI, Herb. L. Pinzani). – Casual alien species confirmed for the flora of Toscana.

Honorius nutans was last reported in Toscana by Baroni (1908). At the site, this species forms a small population consisting of 20 mature individuals.

L. Pinzani

Hydrangea macrophylla (Thunb.) Ser. (Hydrangeaceae)

+ (NAT) VEN. – Status change from casual to naturalized alien for the flora of Veneto.

In Veneto Hydrangea macrophylla is considered as casual alien in Vicenza province (Masin and Scortegagna 2012; Argenti et al. 2019). A new population was found in 2008 in Sedico (Belluno): fraz. Peron (CFCE: 9838/2), margin of road, 400 m, 7 July 2008, C. Argenti (RO, Herb. C. Argenti). Subsequent field surveys (up to July 2022) confirmed the occurrence of this population and led to discover further two populations in Borgo Valbelluna (Belluno), fraz. Cordellon and in Gosaldo (Belluno), fraz. Zavat. The species regularly produces abundant flowers and it is able to sustain itself. We consider H. macrophylla as naturalized in Veneto.

D. Iamonico, C. Argenti

Juglans nigra L. (Juglandaceae)

+ (CAS) MAR: Apecchio (Pesaro e Urbino), fraz. Serravalle di Carda (WGS84: 43.537994°N, 12.503523°E), vegetazione arbustiva su suolo calcareo legata alla dinamica di rinaturalizzazione di un frutteto abbandonato, 680 m, 28 August 2022, leg. G. Mei, E. Ligato, S. Tassone, det. G. Mei (FI, Herb. G. Mei). – Casual alien species new for the flora of Marche.

A couple of young individuals originated from seed, about 30 cm tall, were observed in an uncultivated area occupied by disturbed vegetation dominated by shrubs and lianose plants. Nearby there is a walnut tree, about 10 m tall, residual of an old planting.

G. Mei, S. Tassone, E. Ligato

Lepidium virginicum L. subsp. virginicum (Brassicaceae)

+ (NAT) SAR: Palau (Nord-Est Sardegna), loc. Porto Pollo (WGS84: 41.189607°N, 9.321279°E), duna fissa con Ephedra distachya e Armeria pungens, presente in una vasta area del sistema dunale e lungo le cunette stradali, 23 m, 2 June 2022, G. Brundu, V. Lozano (FI, Herb. UniSS-Agraria). – Naturalized alien species new for the flora of Sardegna.

This species was observed also on the eastern coast of Sardegna, in a dusty parking area (WGS84: 40.479964°N, 9.808424°E).

G. Brundu, V. Lozano

Ligustrum lucidum W.T.Aiton (Oleaceae)

+ (INV) LAZ. – Status change from naturalized to invasive alien for the flora of Lazio.

In recent years, the rapid colonization by Ligustrum lucidum from seeds has been observed in several sites in the Rome metropolitan area (e.g., WGS84: 41.914809°N, 12.471324°E; 41.919734°N, 12.474257°E), particularly along the river Tevere, on monuments and in archaeological sites (Celesti-Grapow and Ricotta 2020).

L. Celesti-Grapow, F. Emili

+ (CAS) BAS: Potenza (Potenza), Fiume Basento (WGS84: 40.628475°N, 15.808076°E), lungo le sponde, 665 m, 25 June 2022, leg. L. Rosati, det. L. Rosati, G. Potenza, S. Fascetti (FI, HLUC No. 13881). – Casual alien species new for the flora of Basilicata.

Several flowering individuals were observed within the patches of a Salix alba L. riparian forest.

G. Potenza, L. Rosati, S. Fascetti

Lobelia erinus L. (Campanulaceae)

+ (CAS) SAR: Villanovaforru (Sud Sardegna), ambiente urbano (WGS84: 39.632595°N, 8.865828°E), crepe dei muri e marciapiedi, 328 m, 8 June 2022, F. Mascia, L. Podda, G. Bacchetta (FI, CAG). – Casual alien species new for the flora of Sardegna.

Some individuals were found inside the village.

F. Mascia, L. Podda, G. Bacchetta

Magnolia grandiflora L. (Magnoliaceae)

+ (CAS) LOM: Gardone Riviera (Brescia), Piazza P. Scarpetta, di fronte al municipio (WGS84: 45.621831°N, 10.561928°E), aiuola, 116 m, no exp., 15 April 2022, leg. et det. M. Merli, conf. G. Galasso (FI). – Casual alien species new for the flora of Lombardia.

M. Merli, G. Galasso

Melia azedarach L. (Meliaceae)

+ (CAS) LOM: Milano (Milano), Parco del Ticinello (WGS84: 45.421100°N, 9.182687°E), boschina spontanea, 107 m, no exp., 15 June 2022, G. Galasso (FI, MSNM barcode MSNM51916, MSNM51917). – Casual alien species new for the flora of Lombardia.

G. Galasso

Mesembryanthemum × vascosilvae (Gideon F.Sm., E.Laguna, Verloove & P.P.Ferrer) L.Sáez & Aymerich (Aizoaceae)

+ (CAS) CAM: Positano (Salerno), arcipelago de Li Galli, Isola del Gallo Lungo (WGS84: 40.582144°N, 15.443412°E), margini della pineta su rupi calcaree marittime, ca. 20 m, 30 June 2022, E. Del Guacchio, R. Vallariello, L. Paino, C. Guidone (FI). – Casual alien nothospecies new for the flora of Campania.

Massively planted as ground cover along paths on this islet and escaped. Formally described only in recent times (Smith et al. 2020, sub Aptenia), this overlooked hybrid is widely cultivated throughout Italy, nowadays more than its parental Mesembryanthemum cordifolium L.f. The repeated indications for Campania of the latter species (Capri Island) (Del Guacchio and La Valva 2017) need to be verified.

E. Del Guacchio, R. Vallariello, G. Galasso

Narcissus Jonquilla and Apodanthus Daffodil Group (Division 7) (Amaryllidaceae)

+ (CAS) VEN: San Giovanni Ilarione (Verona), loc. Castello, a S della chiesa di San Giovanni Battista (WGS84: 45.52671016°N, 11.23706344°E), argine boscato, una decina di cespi, 295 m, 7 March 2022, leg. F. Menini, det. E. Banfi (FI, VER No. SA926). – Casual alien cultivar group new for the flora of Veneto.

The collected plants showed the characteristics of the cultivar ‘Sweetness’.

F. Menini, E. Banfi, G. Galasso

Oenothera speciosa Nutt. (Onagraceae)

+ (CAS) SAR: Masainas (Sud Sardegna), loc. Sa Reina (WGS84: 39.044167°N, 8.623333°E), incolti, 38 m, 29 April 2021, A. Pisano, G. Bacchetta, A. Lallai (FI, CAG). – Casual alien species new for the flora of Sardegna.

Some specimens have been found growing in the pastures near houses.

A. Pisano, G. Bacchetta, A. Lallai

Oxalis purpurea L. (Oxalidaceae)

+ (CAS) CAL: Palmi (Reggio Calabria), Contrada Sant’Elia (WGS84: 38.332833°N, 15.839583°E), bordo sentiero in terra battuta, 550 m, 14 April 2022, leg. G. Posillipo, det. V.L.A. Laface, C.M. Musarella, G. Posillipo, G. Spampinato (FI, REGGIO). – Casual alien species new for the flora of Calabria.

The very small observed population occupies an area of approximately 5 m². In addition to Sicilia, it is naturalized in Campania, but only within the Portici Botanical Garden (Stinca and Motti 2009).

V.L.A. Laface, C.M. Musarella, G. Posillipo

Pachysandra terminalis Siebold & Zucc. (Buxaceae)

+ (CAS) VEN: Verona (Verona), Borgo Trento, Via IV Novembre lungo il marciapiede (WGS84: 45.44454303°N, 10.98968109°E), interstizio alla base del muro di un’abitazione, frammista a Parietaria judaica, 60 m, 21 March 2022, F. Menini (FI). – Casual alien species new for the flora of Veneto.

F. Menini, S. Andreatta

Parthenocissus inserta (A.Kern.) Fritsch (Vitaceae)

+ (INV) TOS. – Status change from casual to invasive alien for the flora of Toscana.

On the ancient wall of the city of Pisa we found many plants covering a large area [sulle mura nei pressi della Torre Piezometrica (WGS84: 43.72034°N, 10.40914°E), invasiva sulle mura, 25 m, 21 May 2022, F. Roma-Marzio 1798 (PI No. 061324)]. Many plants were also observed along the railroad tracks about 5 km from the railway station of Pisa in the direction of Firenze. Furthermore, after a revision of the specimens preserved in PI, it is also reported in the Regional Park of Migliarino-San Rossore-Massaciuccoli [Pisa (Pisa), Parco di Migliarino-San Rossore-Massaciuccoli, Tenuta di Tombolo al Bosco dell’Ulivo (WGS84: 43.60451°N, 10.35298°E), ambienti salmastri e sinantropici, 0–5 m, 9 June 2018, Partecipanti all’escursione Wikiplantbase #Migliarino-San Rossore-Massaciuccoli (PI No. 021484)]. In our opinion, most of the regional data concerning Parthenocissus quinquefolia (L.) Planch. (Peruzzi and Bedini 2013 [onwards]; Roma-Marzio et al. 2016) could be referred to P. inserta. Accordingly, we consider the status of invasive species as more appropriate for P. inserta in Toscana.

F. Roma-Marzio

Paspalum dasypleurum Kunze ex É.Desv. (Poaceae)

+ (NAT) LOM. – Status change from casual to naturalized alien for the flora of Lombardia.

Abundant and frequent in Bergamo, Via Ghisleni Mazzola [(WGS84: 45.699891°N, 9.646808°E), margine erboso, 262 m, no exp., 23 July 2022, E. Banfi (FI, MSNM barcode MSNM52003, MSNM52004, MSNM52005)].

E. Banfi, G. Galasso

Phlox caespitosa Nutt. (Polemoniaceae)

+ (CAS) ITALIA (ABR): L’Aquila (L’Aquila), loc. Palombara (WGS84: 42.342290°N, 13.429072°E), margine stradale, 666 m, 13 April 2020, leg. F. Bartolucci, det. F. Bartolucci, F. Conti (FI, APP No. 66130). – Casual alien species new for the flora of Italy (Abruzzo).

The collected specimen was identified following Wherry (1955) and Brown (2000). A few plants have been observed from 2019 to today, growing spontaneously along the roadside.

F. Bartolucci, F. Conti

Phyllostachys viridis (R.A.Young) McClure (Poaceae)

+ (NAT) LOM. – Status change from casual to naturalized alien for the flora of Lombardia.

In several small woods in Milano [Boscoincittà (WGS84: 45.482703°N, 9.094525°E), robinieto, 131 m, no exp., 2 June 2022, leg. G. Galasso, det. E. Banfi & G. Galasso (MSNM barcode MSNM51900, MSNM51901, MSNM51902, MSNM51903, MSNM51904); Parco del Ticinello, lungo la Roggia Ticinello, pressi di Cascina Campazzino (WGS84: 45.419655°N, 9.187769°E), boschetto su sponda di roggia, 108 m, no exp., 15 June 2022, leg. G. Galasso, det. E. Banfi & G. Galasso (MSNM barcode MSNM51918)] and Bergamo [Via San Sebastiano, lato a monte (WGS84: 45.710874°N, 9.635844°E), pendio erboso stradale, 380 m, NW, 17 June 2022, E. Banfi (MSNM barcode MSNM51922); Via Castagneta, lato a monte (WGS84: 45.718273°N, 9.656700°E), margine erboso stradale, 290 m, NE, 24 June 2022, E. Banfi (MSNM barcode MSNM51923)], crop residues expand widely within the undergrowth or along the edges.

E. Banfi, G. Galasso

Picea orientalis (L.) Peterm. (Pinaceae)

+ (CAS) PIE: Torino (Torino), Collina di Torino, versante N presso il Colle della Maddalena (WGS84: 45.030659°N, 7.717236°E), bosco misto di latifoglie in prossimità di un piccolo nucleo artificiale di Picea orientalis, 658 m, 21 January 2022, M. Lonati, G. Nota, D. Barberis (FI). – Casual alien species new for the flora of Piemonte.

Numerous seedlings are present at this site below the canopy of broadleaf trees. Indeed, this species is markedly shade-tolerant in its juvenile stages.

M. Lonati, G. Nota, D. Barberis

Platycladus orientalis (L.) Franco (Cupressaceae)

+ (NAT) ABR. – Status change from casual to naturalized alien for the flora of Abruzzo.

Abundant, sexually reproducing individuals were found on the vertical walls of the Spanish Fort, in the urban area of L’Aquila [(WGS84: 42.354040°N, 13.403478°E), muri, 730 m, 18 June 2022, E. Fanfarillo, L. de Simone (SIENA)].

E. Fanfarillo, L. de Simone

Pseudotsuga menziesii (Mirb.) Franco (Pinaceae)

+ (CAS) PIE: Valchiusa (Torino), Meugliano, Lago di Meugliano (WGS84: 45.475756°N, 7.791080°E), aree boscate in prossimità di un rimboschimento artificiale a Pseudotsuga menziesii, 748 m, 16 May 2022, S. Ravetto Enri, A. Mainetti, M. Pittarello (FI). – Casual alien species new for the flora of Piemonte.

The spontaneous reproduction of this species has been observed in many Italian administrative regions in recent (Bartolucci et al. 2019) and former (Ciancio et al. 1981) times. In Piemonte, several young individuals (less than 1-m high) have been observed under the canopy cover of a plantation established in the 1930s.

S. Ravetto Enri, A. Mainetti, M. Pittarello

Quercus palustris Münchh. (Fagaceae)

+ (NAT) ITALIA (LOM). – Status change from casual to naturalized alien for the flora of Italy (Lombardia).

Having had the opportunity to easily access the area of the former Piazza d’Armi in Milano, it was possible to verify that the population of Quercus palustris (Galasso et al. 2021) occurring there can be considered naturalized.

G. Galasso

Sarcococca confusa Sealy (Buxaceae)

+ (CAS) ITALIA (ABR): Teramo (Teramo), Via dei Tribunali, fioriere sul bordo stradale, in zona ombrosa (WGS84: 42.658055°N, 13.708008°E), ca. 260 m, 10 November 2021, N. Olivieri (FI). – Casual alien species new for the flora of Italy (Abruzzo).

Sarcococca confusa is quite widespread in cultivation as ornamental in shady areas. Some young plants were identified according to McKean (2011).

N. Olivieri

Senecio angulatus L.f. (Asteraceae)

+ (NAT) MOL: Termoli (Termoli), Via Corsica in prossimità dell’incrocio con Via Sant’Elena (WGS84: 41.991205°N, 14.999781°E), incolto sul bordo strada, 31 m, 4 January 2022, M. Lonati, M. Probo (FI). – Naturalized alien species new for the flora of Molise.

This species is widespread in Termoli, also occurring in some uncultivated areas near the medieval village.

M. Lonati, M. Probo

Setaria adhaerens (Forssk.) Chiov. (Poaceae)

+ (NAT) VEN: Venezia (Venezia), Isola di Sant’Erasmo, 50 m a NE della chiesa (WGS84: 45.459477°N, 12.410954°E), orto, 0 m, 31 October 2021, S. Tasinazzo (FI); ibidem, Lido (WGS84: 45.364906°N, 12.337115°E), orto, 0 m, 14 October 2022, S. Tasinazzo (Herb. S. Tasinazzo); Cavallino-Treporti (Venezia), Via Sette Casoni (WGS84: 45.466540°N, 12.503309°E), campo di asparagi in stadio post-colturale, 0 m, 6 November 2021, S. Tasinazzo (Herb. S. Tasinazzo). – Naturalized alien species new for the flora of Veneto.

Some specimens were found on sandy soil.

S. Tasinazzo

Sisyrinchium rosulatum E.P.Bicknell (Iridaceae)

+ (NAT) TOS: Lucca (Lucca) (WGS84: 43.8457678°N, 10.5153513°E), prati umidi, 14 m, 13 May 2022, S. Maccherini, L. de Simone, E. Fanfarillo (FI, SIENA). – Naturalized alien species new for the flora of Toscana.

Numerous fructifying adult individuals were found in an urban mowed grassland dominated by Agrostis stolonifera L. subsp. stolonifera and Lolium perenne L.

S. Maccherini, L. de Simone, G. Bacaro

Solanum carolinense L. (Solanaceae)

+ (NAT) LAZ. – Status change from casual to naturalized alien for the flora of Lazio.

In Lazio, this species was first recorded in Roma in 2015 as a casual alien (Olivieri 2015). The new populations [Fumone (Frosinone), Vicinale Pozzi (WGS84: 41.73029511°N, 13.26961270°E), margine stradale, 621 m, 8 August 2022, E. Fanfarillo (SIENA); Alatri (Frosinone), strada SR155 (WGS84: 41.736187°N, 13.344255°E), 416 m, 9 August 2022, E. Fanfarillo (SIENA)] appear well-established, especially the one in Alatri, which was also observed in the past two years.

E. Fanfarillo

Solanum sisymbriifolium Lam. (Solanaceae)

+ (NAT) CAL: Crotone (Crotone), lungo la strada SS106, in loc. Passovecchio, nei pressi della cartiera (WGS84: 39.106411°N, 17.097683°E), formazioni prative rude­rali, 7 m, 28 September 2021, leg. G De Fine, det. N.G. Passalacqua (FI). – Naturalized alien species new for the flora of Calabria.

N.G. Passalacqua, G. De Fine

Toxicodendron radicans (L.) Kuntze subsp. radicans (Anacardiaceae)

+ (NAT) ITALIA (TOS): Impruneta (Firenze), ai Sassi Neri nei pressi della fonte della Caldaia, lungo il fosso di Narbi (WGS84: 43.683644°N, 11.271573°E), bosco mesofilo e ambienti rocciosi umidi su serpentino, 230 m, 15 June 2022, leg. G. Astuti, A. Cutroneo, F. Roma-Marzio, R. Vangelisti, det. F. Roma-Marzio, G. Astuti (FI, PI Nos. 061456, 061458). – Status change from casual to naturalized alien for the flora of Italy; naturalized alien species new for the flora of Toscana.

In Italy, this species is reported as casual alien only in Trentino-Alto Adige (Galasso et al. 2018), based on two old records by Gelmi (1893) and Biasioni (1930). Accordingly, the Tuscan population is the only recent record for Italy and the first case reported as naturalized species. Special attention is recommended with this species, commonly known as poison ivy, which in North America is causing serious allergic contact dermatitis to millions of people every year (Kim et al. 2019).

G. Astuti, F. Roma-Marzio, R. Vangelisti

Trigonella foenum-graecum L. (Fabaceae)

+ (NAT) SAR. – Status change from casual to naturalized alien for the flora of Sardegna.

The species was frequently found in marginal segetal habitats (fields of cereal crops, such as barley and oats) and in arid meadows of therophyte communities, mainly on sandy-clayey substrates (Baràdili, Oristano; Collinas and Villanovaforru, Sud Sardegna). The populations are clearly established since some time in the territories and are to be related to intentional (cultivation of fenugreek for zootechnical purposes) or unintentional (cereal seed contamination) historical introductions.

F. Mascia, G. Bacchetta, M. Fois

Triticum × requienii Ces., Pass. & Gibelli nothosubsp. requienii (Poaceae)

+ (CAS) TOS: Asciano (Siena), loc. Biancane di Leonina (WGS84: 43.295584°N, 11.452733°E), calanchi, 225 m, 31 May 2022, leg. et det. L. Pinzani, A. Stinca, conf. E. Banfi (FI, IT, Herb. L. Pinzani). – Casual alien nothospecies new for the flora of Toscana.

Triticum × requienii was first reported for Italy by Raimondo et al. (2010), under the name ×Aegilotriticum triticoides van Slageren, in Sicilia, then by Ardenghi and Polani (2016) in Lombardia. In Asciano, a few individuals of this nothotaxon have been observed within the therophytic plant communities of the clay flows at the base of the gullies (locally called ‘Biancane’).

L. Pinzani, A. Stinca, E. Banfi

Tulipa gesneriana L. subsp. gesneriana (Liliaceae)

+ (CAS) TOS: Bagno a Ripoli (Firenze), loc. Candeli, tra Lasi e La Massa (WGS84: 43.764465°N, 11.340489°E), oliveto, 72 m, 16 April 2022, L. Pinzani (FI). – Casual alien species confirmed for the flora of Toscana.

This species forms a population consisting of a few scattered flowering individuals, distributed within an olive grove.

L. Pinzani

Wisteria sinensis (Sims) DC. (Fabaceae)

+ (NAT) PIE: Gifflenga (Biella), sponde del Torrente Cervo, a monte del guado tra Gifflenga e Buronzo (WGS84: 45.49035°N, 8.24381°E), vegetazione alloctona sulle sponde e greto del Torrente Cervo, 176 m, 3 October 2021, A. Selvaggi (FI, Herb. A. Selvaggi); Carignano (Torino), sponda sinistra Fiume Po, presso imbarco Società canottieri Padus (WGS84: 44.90794°N, 7.69109°E), vegetazione alloctona sulle sponde del Fiume Po, 230 m, 17 July 2022, A. Selvaggi (FI, Herb. A. Selvaggi). – Naturalized alien species confirmed for the flora of Piemonte.

Previously recorded in Piemonte only in “Vignole Borbera, in luogo abbandonato” (Carrega and Silla 1995) and in the Natural Reserve of “Garzaia di Valenza” (Ostellino 1987), without any indication of the degree of naturalization. A couple of specimens escaped from cultivation have been also reported on the outskirts of Cherasco (Cuneo) (Rota and Cavallo 2012).

A. Selvaggi

Yucca gloriosa L. (Asparagaceae)

+ (NAT) SAR. – Status change from casual to naturalized alien for the flora of Sardegna.

A dense population originating from clonal growth and formed by several shrubs was found in Porto Torres (Sassari), close to the Rio Mannu estuary (WGS84: 40.835207N, 8.391014E). Other small naturalized populations were found on sand dunes at Is Arenas [San Vero Milis (Oristano), WGS84: 40.059102°N, 8.466568°E] and in coastal areas of the island of San Pietro [e.g., Carloforte (Sud Sardegna), spiaggia La Caletta, WGS84: 39.117101°N, 8.257647°E].

G. Rivieccio, G. Brundu, S. Bagella

Nomenclatural and distribution updates from other literature sources

Nomenclatural, status, and distribution updates, and corrections to Galasso et al. (2018) and subsequent updates summarised in the Portal to the Flora of Italy (2022) are provided in Suppl. material 1.

G. Galasso, F. Bartolucci

We gratefully acknowledge Lorenzo Peruzzi, who provided distribution information.