Najas marina subsp. armata, Horn

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), pp. 91-101 : 94-96

Najas marina subsp. armata in the N Mediterranean

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.

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).

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.