Family |
Urticaceae
Parietaria lusitanica
L.
Parietaria lusitanica L.
(Sp. Pl.: 1052; 1753 – Nouvelle Flore du Liban et de la Syrie, vol. 2, Pl. CLXXX nº 2; 1969)
• Life-form & habit: Annual or short-lived perennial herb, 10–40 cm tall, with slender, erect to ascending stems that are much branched and green or reddish. Plant glabrous or sparsely pubescent, often translucent and delicate in texture.
• Leaves: Alternate, ovate to lanceolate, 10–40 × 5–15 mm, entire, glabrous, translucent, and often shining; base rounded or subcordate, apex acute; petiole slender, 5–20 mm. Stipules minute or absent.
• Inflorescence & flowers: Small axillary cymes of 3–10 minute, greenish or reddish flowers, often crowded in the upper leaf axils. Perianth of 4 unequal segments; staminate and pistillate flowers usually on the same plant. Staminate flowers with 4 stamens that spring outward explosively when mature; pistillate flowers with a single erect ovary and bifid stigma.
• Fruit: Achene small, obovoid, compressed, smooth, black and shining, c. 1 mm long, enclosed by the persistent perianth.
• Phenology: Flowers and fruits almost year-round in humid or shaded habitats, mainly from February to October.
• Habitat & elevation: Shaded walls, rocky crevices, gardens, old ruins, and disturbed habitats, typically from sea level to 1 200 m; prefers calcareous or stony soils with some humidity.
• Lebanese distribution: Common throughout Lebanon — coastal plains, old towns, and mountain villages; recorded by Mouterde from Beirut, Jezzine, Zahlé, Barouk, and Dahr el-Baïdar, often growing in shaded stone walls and humid rock fissures.
• Native to: Afghanistan, Algeria, Baleares, Bulgaria, Corse, Cyprus, East Aegean Is., France, Greece, Gulf States, Iran, Iraq, Italy, Kriti, Krym, Lebanon-Syria, Libya, Morocco, North Caucasus, NW. Balkan Pen., Pakistan, Palestine, Portugal, Sardegna, Sicilia, Spain, Transcaucasus, Tunisia, Turkmenistan, Türkiye, Türkiye-in-Europe, Ukraine (POWO).
• Introduced into: St.Helena (POWO).
• ⚠️ Taxonomic note: A common and widespread Parietaria species of the Mediterranean and Irano-Turanian regions, easily recognised by its slender translucent stems, entire ovate leaves, and minute greenish axillary flowers. It is closely related to Parietaria judaica L. but differs by its smaller, more delicate habit, annual life cycle, and smooth, glossy achenes. In Lebanon, it is frequent on shaded limestone walls and humid valleys, sometimes forming large mats under old terraces or ruins.