Scilloideae - Morphology

Morphology

Morphologically the subfamily is characterised by having 6 tepals and 6 stamens with a superior ovary, a characteristic which placed them within the older order of Liliales in many older classification systems, such as the Cronquist system, but they now separate from them within the Asparagales order. They have also been included in the Liliaceae family.

Roots: contractile and mucilaginous.

Leaves: fleshy and mucilaginous arranged in a basal rosette, alternate and spiral, simple, margin entire, with parallel venation, sheathing at the base, without stipules and hair simple.

Flowers: arranged in scapiflorous inflorescences (in racemes, in spikes, and in heads). The peduncles are articulated. The flowers are hermaphroditic, actinomorphic, often showy.

Perianths: six tepals divided into two whorls, free or joined (connate). When joined, the perianth forms a tubular bell. The tepals are imbricate and petaloid. The corolla may be white, yellow, violet, blue, brown and even black (see images).

Androecium: composed of 6 stamens (exceptionally 3, as in Albuca, for example), with the filaments free or adnate to the tube, often appendiculate. The anthers are dorsifixed and pollen dehiscence occurs by longitudinal openings. The pollen is monosulcate (having a linear furrow).

Gynoecium: superior ovary, tricarpelate, connate and trilocular. Single stigma, capitate to 3-lobed. May contain from one to several ovules in each locule. They have nectaries at the septa of the ovaries.

Fruit: dehiscence loculicidal.

Seed: Seed morphology is diverse, from globular to flattened, and occasionally aril. The seed coat usually contains phytomelan (phytomelanin), one of the defining characteristics of the order, a black pigment present in the seed coat, creating a dark crust.

Chromosomes: Chromosome size varies widely, from 1.2 to 18 microns in length, karyotype bimodal or trimodal. The basic chromosome number is also very variable (X = 2, 6, 7, 10, 15, 17, etc..).