Polygala L.

Genus composed of about 620 species, mostly herbaceous. In North Africa it is represented by 16 taxa, most of which are herbaceous. Only P. balansae could be considered shrubby, but a further 5 species that are somewhat woody at the base of the stems can be cited. These are:

P. munbyana Boiss. & Reut. [Polygaloides munbyana (Boiss. & Reut.) O. Schwarz], glabrescent, but little or not at all spiny, with quadrangular stems, shortly winged, and with lighter flowers (pink or yellow); endemic to the littoral and sublittoral mountains of NE Morocco (from littoral Bokkoyas towards the E) and the coastal mountains of central-western Algeria.

P. webbiana Coss. [Polygaloides webbiana (Coss.) O. Schwarz], easily differentiated by its densely pubescent branchlets; present in southern Spain (Malaga) and NW Morocco (calcareous mountains of the western Rif and, although rarer, also in the Middle Atlas, in Bab Metik).

P. sinaica Botsch., spiny subshrub, deciduous, smaller than P. balansae (up to 0.5 m in height), velvety-pubescent. Racemes lax, terminal, with up to 10 flowers, calyx with membranous external sepals, with a wide green vein, white internal sepals (wings), elliptic, with dense brown-greenish venation. Stony deserts, dried watercourses (wadis), cracks in rocky outcrops in Sinai Peninsula, Negev, Palestine and Arabian Peninsula.

P. aschersoniana Chodat, suffruticose plant with somewhat thick leaves with revolute margin, glabrous, linear-lanceolate and short racemes, with few flowers; sepals linear with highly visible green veins. A remarkable endemism to the mountainous areas of NE Libya (Cyrenaica), from the Akhdar Massif to Derna. This species’ closest relatives are in Sicily, Sardinia and mountains in Greece and the Aegean Sea.

P. rupestris Pourr. (incl. P. saxatilis Desf.), very different from the above for being more herbaceous; leaves membranous, not coriaceous, not deciduous; outer sepals and wings persistent; upper petals larger than the keel and crest highly developed and fimbriate. This is a rare species, but widely distributed across the Mediterranean non-steppic area of Morocco, Algeria and Tunisia. In addition to subsp. rupestris, a further 2 subspecies are recognised: subsp. font-queri Pau ex Font Quer, endemic to Morocco, and subsp. oxycoccoides (Desf.) Batt., a dwarf herbaceous plant with obovate and somewhat thick leaves, present in Algeria and Morocco.

Relatively common and widespread species, they are not considered threatened, except maybe for P. aschersonia that has a small distribution area and of which little is known. Currently, they have not been assessed at a global level in the IUCN Red List of Threatened Species. In Algeria it is included in the List of protected non cultivated flora (Executive Decree 12-03 on 4-Jan-2012). P. sinaica var. sinaica has been recently listed as “Endangered” (El-Khalafy et al. in Phytotaxa 502(3): 237-258, 2021).

Updated by: A. Lahora.