Epilobium tetragonum

Επιλόβιο το τετράγωνο

Etymology of Epilobium tetragonum: "Epilobium" comes from the Ancient Greek "επί+λοβός" [epi+lovos], which means "upon a lobe/pod/capsule" as the flower and capsule appear together, the corolla being borne on the end of the ovary. "Tetragonum" comes from Ancient Greek "τετραγωνο" [tetragono], and it means "square, with four corners, with four sides", referring to its stalk (main stem) which is supposedly square-shaped. Epilobium species have stems that are distinctly square-shaped, rather than being rounded or cylindrical like many other plant stems. If you were to make a cross-section of the stem and look at it under a microscope, you would see four distinct sides or corners, giving it a square appearance. This is different from the typical circular cross-section seen in most plants.

At least seven Epilobium taxa on their own in Cyprus, all of them quite uncommon or rare.

Epilobium tetragonum is a near-threatened plant in Cyprus, a fact that automatically marks it as a rare plant. It appears only in central mountainous Cyprus, between an altitude of 150-1525 metres. It primarily grows near streams. Its flowering period is between May and July.

How to identify Epilobium tetragonum:

Six of the seven Epilobium taxa have their lower leaves opposite, their flowers solitary, axillary, actinomorphic, and their petals bilobed at the apex. Only Epilobium angustifolium differs.

Tetragonum's stigma is clavate, without lobes. This appears also in tournefortii, and lamyi. Tournefortii's petals are at a minimum 7mm long, up to 13mm, but for the other two, it's less than 7mm.

Tetragonum is very similar to lamyi, but their key difference is the fact that its leaves are more or less decurrent on the stems-ridges, lamyi's are clearly not.