Morinaceae

Abstract

Shrubs or perennial herbs with basal leaf rosettes and initial taproot, basal part of axis (“rootstock”) mostly covered with the remains of old leaf bases. Leaves of vegetative and flowering shoots opposite or whorled, exstipulate, simple, lanceolate, entire or mostly deeply lobed, margin entire, dentate or with spiny bristles; lamina basally tapering into a rather indistinct petiole, petioles in most species basally connate to form cylindrical sheaths. Flowers hermaphrodite, white, yellow or pink to purple, in terminal compact thyrses with 1–3-flowered cymes, or cymes in the axils of showy opposite or verticillate bracts, forming “verticillasters”, these forming a head-like or cylindrical thyrse. Involucel (= epicalyx) 12-veined, of 4 fused bracteoles, cylindrical-campanulate, rim with few to numerous spiny teeth or seta 2. Calyx 4–5-merous, cupular or tubular, zygomorphic, with oblique, weakly 5-lobed opening (Acanthocalyx) or 2-lipped with lips 2- or 3-lobed or emarginate (Morina). Corolla of (4)5 petals, with a narrow tube, often curved, often villous outside, limb scarcely to markedly 2-lipped, lobes (4)5, spreading; in some species of Morina the corolla is shorter than the calyx and sometimes not or scarcely opening at anthesis (flowers possibly cleistogamous). Stamens 4 in two pairs, borne in the corolla tube, all fertile, or the 2 posterior fertile and the anterior sterile. Anthers introrse, 2-celled, locules subequal or markedly unequal, opening by longitudinal slits. Nectary at abaxial inside base of the corolla tube, covered with hairs, either cushion-like and uni- or trilobed, rarely bilobed, or nectary indistinctive. Ovary inferior, 3-locular with two locules containing sterile ovules only or 1-locular, pseudomonomerous, formed by the fusion of one lateral, fertile carpel and two solid, sterile carpels, ovule solitary, pendant. Style simple, slender, stigma disk-shaped. Fruit dry, 1-seeded, indehiscent (achene), enclosed in the involucel, when present, and surmounted by the ± persistent calyx, the fertile carpel elongated into a prominent tip. Endosperm copious, embryo large or small.

Hofmann Ursula (deceased).