taxonID	type	description	language	source
BC1C8324FFFFFFD7FEB9AA85FED0F9C4.taxon	materials_examined	– Lectotype (designated by Triest 1987: 29): Egypt, Delile in Herb. Delile (MPU 007340 [image!]). – Notes: the type was indicated as “ holotype ” by Triest (l. c.), to be corrected to lectotype (McNeill 2014) under Art. 9.10 of the Code (Turland & al. 2018). I was unable to find duplicates of MPU 007340 or other relevant specimens, but the illustration published as part of the protologue is another element of original material (Art. 9.4 (b )). Both N. delilei and N. armata are replacement names for N. muricata Delile, which is a later homonym of N. muricata Thuill. and therefore illegitimate (Art. 53.1); N. armata was nomenclaturally superfluous when published and is therefore illegitimate (Art. 52.1); consequently N. marina subsp. armata is not a new combination but rather a replacement name (Art. 58.1).	en	Troia, Angelo (2022): The unnoticed northward expansion of Najas marina subsp. armata (Hydrocharitaceae) in the Mediterranean area: an effect of climate change? Willdenowia 52 (1): 91-101, DOI: 10.3372/wi.52.52106, URL: https://doi.org/10.3372/wi.52.52106
BC1C8324FFFFFFD7FEB9AA85FED0F9C4.taxon	discussion	Najas marina subsp. armata is the name and rank adopted by Triest in his revisions of the genus Najas in Africa (Triest 1987) and the Old World (Triest 1988). Before him, the taxon was variously treated: as a variety (Rendle 1899; Fiori 1923; Maire 1952; Cirujano & Lopez Alberca 1984), subspecies (Horn af Rantzien 1952) or species (Delile 1813 – 1814; Braun 1864; Rouy 1912; Lindberg 1932; Taeckholm & Drar 1941). After Triest, the taxon has been generally accepted at infraspecific rank (Uotila 2009), sometimes doubtfully (Pignatti 1982; Bartolucci & al. 2018), but sometimes it was merged with N. marina subsp. intermedia (POWO 2022) or not mentioned at all (Pignatti & al. 2017). Rarely it is accepted as a separate species, and in that case the correct name is N. delilei (Feinbrun-Dothan 1991). Najas marina subsp. armata is a well-separated taxon and, according to the available knowledge, subspecific rank seems to be the most appropriate. Diagnostic characters were already identified by Triest (1988, 1989), but they are summarized below in a new key also to update the nomenclature (with seed length measurements modified according to Rüegg & al. 2019).	en	Troia, Angelo (2022): The unnoticed northward expansion of Najas marina subsp. armata (Hydrocharitaceae) in the Mediterranean area: an effect of climate change? Willdenowia 52 (1): 91-101, DOI: 10.3372/wi.52.52106, URL: https://doi.org/10.3372/wi.52.52106
BC1C8324FFFFFFD7FEB9AA85FED0F9C4.taxon	discussion	It is interesting to report that, in addition to being eaten by wild birds such as waterfowl (Aves: Anatidae) (Les 2020), in Egypt Najas marina subsp. armata is collected and dried to be used as fodder for sheep and goats (Yousif & al. 2020).	en	Troia, Angelo (2022): The unnoticed northward expansion of Najas marina subsp. armata (Hydrocharitaceae) in the Mediterranean area: an effect of climate change? Willdenowia 52 (1): 91-101, DOI: 10.3372/wi.52.52106, URL: https://doi.org/10.3372/wi.52.52106
BC1C8324FFFEFFD0FA3DADC8FE6DF8A4.taxon	discussion	Although Najas marina subsp. armata was not reported from Sicily in the checklists and floras of Lojacono-Pojero (1908 – 1909), Uotila (2009), Pignatti & al. (2017) and Bartolucci & al. (2018), its presence on the island was reported in some 20 th century works, namely Fiori (1923), Maire (1952), Horn af Rantzien (1952) and Pignatti (1982). Also Triest (1987) had some doubts: “ whether subsp. armata occurs in Sicily could not be stated here ”. Owing to the lack of specific reports and specimens, it can be hypothesized that these references are based on occasional casual populations (and misidentifications cannot be excluded, at least in the first case). Even before Fiori (1923), the taxon was clearly drawn in the pre-Linnaean work of Francesco Cupani (1657 – 1710), under the polynomial “ Fluvialis atrorubens, angusto brevique folio, undequaque spinis infesto ” (Cupani 1713: t. 160; Fig. 1). It can be assumed that the collection site was in Sicily, but it is impossible to know if the depicted plant was cultivated, escaped from cultivation or casual. Even though the full details are not known, this is a very interesting report, deserving further investigation, also because the period 1675 – 1715 has been said to denote the climax of the “ Little Ice Age ” in Europe (Luterbacher & al. 2001). The oldest herbarium specimens found are dated between 2005 and 2008 (Barone & al. 2007; Galesi in Giardina & al. 2007; Sciandrello 2009; see above in Introduction). In addition to the records mentioned above, new populations were found during the present investigations (see Table 1 and Appendix), all of them in the thermomediterranean bioclimatic belt (Bazan & al. 2015). Most of the sites where Najas marina subsp. armata occurs in Sicily (Fig. 2) are reservoirs or farm ponds (Table 1), which are artificial habitats of different sizes (from 0.001 to 0.9 km 2). There are two important exceptions in coastal, natural, shallow lakes within protected areas. The first is Lago Murana, within the Reserve “ Lago Preola e Gorghi Tondi ”; this lake was dry for 23 years owing to reduced rainfall and illegal wells but returned to being a lake in 2005 (Andreotti 2007); in 2012 a submerged meadow with Chara sp. was present (Salvatore Pasta pers. comm.), and only in 2018 was N. marina subsp. armata found there instead of the Chara meadow (Troia & al. 2018). The second is Biviere di Gela, also a shallow lake within a reserve; N. marina subsp. armata was not reported there in 2006 (Brullo & Sciandrello 2006) but was collected there in 2008 (Minissale & Sciandrello, CAT 031869, see Appendix). In both cases, it is clear that N. marina subsp. armata recently arrived and colonized those sites. According to the available data, the taxon in Sicily grows in permanent waters (but in Spain it was reported also in temporary waters; Cirujano & Lopez Alberca 1984). Data for Sicilian populations seem to confirm the ecology of Najas marina subsp. armata, which according to the literature prefers waters rich in Cl−, Ca 2 + and SO 2 − 4 (Cirujano & Lopez Alberca 1984; Triest 1989), with conductivities ranging from 1.45 to 9 mS / cm− 1 (Triest 1989). Najas marina subsp. marina seems to be different, with results showing it to be absent in waters rich in Ca 2 + and HCO − but with a similar range of conductivities (Triest 3 1988, 1989, under N. marina subsp. intermedia). Najas major grows mainly in waters rich in Ca 2 + and HCO − with 3 a conductivity of 0.34 – 1.25 mS / cm− 1 (Triest 1989, under N. marina subsp. marina).	en	Troia, Angelo (2022): The unnoticed northward expansion of Najas marina subsp. armata (Hydrocharitaceae) in the Mediterranean area: an effect of climate change? Willdenowia 52 (1): 91-101, DOI: 10.3372/wi.52.52106, URL: https://doi.org/10.3372/wi.52.52106
BC1C8324FFF9FFD2FEB9ABB5FF46F9C4.taxon	discussion	It seems that the taxon has extended its range northward in the Mediterranean area (Fig. 3) until c. 40 ° N. Note that it was not mentioned for Europe by Dandy (1980). Details of its finds in the main geographical (or political) units of the N Mediterranean are as follows. Portugal – Even though not reported in local or European floras and checklists (e. g. Sequeira & al. 2011), specimens were found in COI and LISI that show the typical spiny stem of this taxon. Spain – Spain hosts one of the oldest populations of Najas marina subsp. armata in Europe, already reported by Triest (1988). Cirujano & Lopez Alberca (1984) correctly identified the taxon (as N. marina var. delilei) and documented its colonization in an artificial wetland in 1980 – 1982, hypothesizing the role of waterfowl.	en	Troia, Angelo (2022): The unnoticed northward expansion of Najas marina subsp. armata (Hydrocharitaceae) in the Mediterranean area: an effect of climate change? Willdenowia 52 (1): 91-101, DOI: 10.3372/wi.52.52106, URL: https://doi.org/10.3372/wi.52.52106
BC1C8324FFF9FFD2FEB9ABB5FF46F9C4.taxon	description	Balearic Islands – Recently found in Minorca (Fraga Arguimbau & al. 2020). Corsica – The only confirmed record was made by Lambinon and Triest (in Jeanmonod & Burdet 1989) from a single pond in 1988. The conductivity of the pond was 5.7 mS / cm− 1. The taxon was neither collected before nor confirmed after from Corsica (Alain Delage pers. comm.). Sardinia – Recently found in S Sardinia (Lazzeri & al. 2013). Crete – Collected in Crete, and for the first time in Europe, in 1974 (Triest 1988). The taxon was considered native in Crete by Dimopoulos & al. (2020) but alien by Korakaki & al. (2021).	en	Troia, Angelo (2022): The unnoticed northward expansion of Najas marina subsp. armata (Hydrocharitaceae) in the Mediterranean area: an effect of climate change? Willdenowia 52 (1): 91-101, DOI: 10.3372/wi.52.52106, URL: https://doi.org/10.3372/wi.52.52106
BC1C8324FFF9FFD2FEB9ABB5FF46F9C4.taxon	materials_examined	Cyprus – Recently found in Cyprus (Hand 2006). Turkey – Uotila (1984) did not report N. marina subsp. armata in his treatment, but Triest (1988) and Triest & Uotila (1988) listed five herbarium specimens of this subspecies, collected in Turkey between 1979 and 1981.	en	Troia, Angelo (2022): The unnoticed northward expansion of Najas marina subsp. armata (Hydrocharitaceae) in the Mediterranean area: an effect of climate change? Willdenowia 52 (1): 91-101, DOI: 10.3372/wi.52.52106, URL: https://doi.org/10.3372/wi.52.52106
BC1C8324FFF7FFDEFD3BAE95FBE5FA84.taxon	materials_examined	ITALY: Sicilia: Mondello, s. d., Ross & Riccobono (PAL 74301) (cited by Lojacono-Pojero 1908 – 1909); ibidem, Jul 1884, Ross (AMD 76304); fosse di Mondello, Jul 1893, Ross (AMD 76303, AMD 76313); Calabria: Roggiano Gravina (Cosenza), Lago dell’Esaro (WGS 84: 39.638220 ° N, 16.160279 ° E), 135 m, sponde, 23 Aug 2018, Peruzzi (FI 065581).	en	Troia, Angelo (2022): The unnoticed northward expansion of Najas marina subsp. armata (Hydrocharitaceae) in the Mediterranean area: an effect of climate change? Willdenowia 52 (1): 91-101, DOI: 10.3372/wi.52.52106, URL: https://doi.org/10.3372/wi.52.52106
BC1C8324FFF7FFDFFD3BA9D5FAD9FC04.taxon	materials_examined	PORTUGAL: Ag. Vila Real de Santo António, Pontão da foz do Rio Guadiana 37.17346 ° N, 07.40605 ° W, 4 Mar 2020, Rita Pina & Paes (LISI 032726); Ervideira, Oct 2020, Palhas 22 (COI 00100975). SPAIN: Andalucía, Almería, Adra, estanque de agua para riego, albufera y salinas viejas, 25 Oct 1969, Sagredo (MA- 01 - 00382393); Castilla-La Mancha, Toledo Quero, Laguna Chica del Taray, 4 Sep 1980, Santos Cirujano (MA- 01 - 00229648, P 02108900); Andalucía, Huelva, Puebla de Guzmán, represa cercana al pueblo, 20 Jul 1989, Silvestre (MA- 01 - 00490893); Comunidad de Madrid, Madrid, Arganda del Rey, laguna de las Madres, 8 Sep 1991, Cirujano & Gil Pinilla (MA- 01 - 00501439, BR 0000027288436 V); Comunidad Valenciana, Alicante, Elche, El Hondo, Charca Norte de Levante, 22 Jun 1994, Cirujano & Medina (MA- 01 - 00548194); Andalucía, Málaga, desembocadura del Guadalhorce, 4 Jun 1997, Conde Alvarez & Orozco (MA- 01 - 00593733); Castilla-La Mancha, Albacete, Ossa de Montiel, lagunas de Ruidera, laguna Lengua, 13 Aug 1998, Cirujano & Medina 113898 (MA- 01 - 00639760); Comunidad Valenciana, Castellón, Almenara, Pardo (MA- 01 - 00432942). ITALY: Sicilia: calanchi a monte dell’invaso Cimia (Mazzarino), 4 Sep 2005, Galesi (CAT 011688); invaso Cimia (Mazzarino), 4 Sep 2005, Galesi (CAT 011696); Diga Cimia (Gela-Mazzarino), 15 Dec 2006, Sciandrello (CAT 008700); Diga Cimia, tra Gela e Mazzarino, 2 Aug 2008, Sciandrello (CAT 008699); Biviere di Gela, 16 Oct 2008, Minissale & Sciandrello (CAT 031869); lago Gorgo pressi Montallegro (AG), 27 Jul 2007, Marrone & Sicilia (PAL 70286); laghetto presso Gibbesi Nuovo, c. 3.5 km NW da Ravanusa (AG), 37.296117 ° N, 13.950898 ° E, c. 350 m, 16 Aug 2019, Troia (PAL); ibidem, 13 Nov 2021, Troia (PAL). GREECE: Kriti (Crete): Prov. Rethimno, Kournas-See, 17 Jul 2009, Mrkvicka (photos at https: // flora. nhm-wien. ac. at / seiten-arten / najas-marina-armata. htm). CYPRUS: Achna dam, 2 Oct 2016, Konstantinou (photos at http: // biodiversitycyprus. blogspot. com / 2016 / 10 / najas - marina-l-cyprus. html). EGYPT: Egypt, Delile in Herb. Delile (MPU 007340 lectotype); Envir. De Darniette, Sieber (P 01756902). ALGERIA: Alger, 1878, Battandier (P 01756797). MOROCCO: In aquis substagnantibus ad ostium omnis Ait-Amer, 15 Jun 1939, Maire & Weiller (P 01756898).	en	Troia, Angelo (2022): The unnoticed northward expansion of Najas marina subsp. armata (Hydrocharitaceae) in the Mediterranean area: an effect of climate change? Willdenowia 52 (1): 91-101, DOI: 10.3372/wi.52.52106, URL: https://doi.org/10.3372/wi.52.52106
