Dopatrium Buch.-Ham.

Scientific Description

Family Scrophulariaceae.

Habit and leaf form. Shrubs, or herbs. Leaves well developed, or much reduced (often scale-like). Annual; plants with a basal concentration of leaves, or with neither basal nor terminal concentrations of leaves; to 0.3 m high. Hydrophytic, or helophytic, or mesophytic, or xerophytic; when hydrophytic, rooted. Leaves of aquatics emergent; minute to small; opposite; ‘herbaceous’, or leathery, or membranous; sessile; simple; epulvinate. Leaf blades entire; oblong, or elliptic; pinnately veined. Mature leaf blades adaxially glabrous; abaxially glabrous. Leaves without stipules. Leaf blade margins entire, or crenate, or serrate, or dentate. Leaves without a persistent basal meristem. Leaf anatomy. Hydathodes present (occasionally), or absent. Hairs absent; glandular hairs absent. Stem anatomy. Secondary thickening developing from a conventional cambial ring.

Reproductive type, pollination. Fertile flowers hermaphrodite. Unisexual flowers absent. Plants hermaphrodite. Entomophilous.

Inflorescence and flower features. Flowers aggregated in ‘inflorescences’; in racemes. The terminal inflorescence unit cymose, or racemose. Inflorescences terminal; very open, flowers single in bract axils. Flowers pedicellate to subsessile; bracteate; ebracteolate; small; very irregular; zygomorphic; 5 merous; tetracyclic. Free hypanthium absent. Hypogynous disk present. Perianth with distinct calyx and corolla; 10; 2 -whorled; isomerous. Calyx present; 5; 1 -whorled; gamosepalous; lobed. Calyx lobes markedly longer than the tube. Calyx erect; imbricate, or valvate; unequal but not bilabiate, or bilabiate, or regular; persistent; with the median member posterior. Corolla present; 5; 1 -whorled; gamopetalous; lobed; imbricate, or valvate; bilabiate; hairy adaxially; purple, or blue; spurred (sometimes), or not spurred; persistent. Androecium 2, or 4. Androecial members adnate (to the corolla); all equal, or markedly unequal (when staminodes present); free of one another; 1 -whorled. Androecium including staminodes, or exclusively of fertile stamens (apparently). Staminodes when present 2 (minute, clavate); representing the anterior-lateral pair. Stamens 2; remaining included; reduced in number relative to the adjacent perianth; fertile stamens representing the posterior-lateral pair; oppositisepalous. Filaments glabrous. Anthers dehiscing via longitudinal slits; introrse; bilocular (cells separate, parallel, equal, lacking awns); tetrasporangiate. Gynoecium 2 carpelled. The pistil 2 celled. Gynoecium non-petaloid; syncarpous; synstylovarious to eu-syncarpous; superior. Ovary plurilocular; 2 locular. Gynoecium median; stylate. Styles 1; simple; attenuate from the ovary, or from a depression at the top of the ovary; apical; persistent. Stigmas 1; 2 - lobed. Placentation axile, or apical. Ovules 50 per locule (to ‘many’); pendulous to ascending; non-arillate; anatropous, or campylotropous, or hemianatropous.

Fruit and seed features. Fruit non-fleshy; not hairy; dehiscent; a capsule. Capsules loculicidal (the 2 valves remaining attached to the placental column). Fruit 50 seeded (to ‘many’). Seeds endospermic. Endosperm oily. Seeds minute. Cotyledons 2. Embryo straight to curved.

Special features. Corolla tube exceeding the calyx; straight. The upper lip of the corolla incorporating 2 members, the lower 3; (posterior, adaxial) lip of the corolla bilobed (shorter than lower lip). Lower (abaxial) lip of the corolla 3 lobed.

Geography, cytology, number of species. Native of Australia. Not endemic to Australia. Australian states and territories: Western Australia, Northern Territory, and Queensland. Northern Botanical Province.