Glossostigma Wight & Arn.

Scientific Description

Common name. Mudmats. Family Scrophulariaceae.

Habit and leaf form. Herbs. Annual, or perennial. Leaves basal and cauline. Plants with a basal concentration of leaves, or with neither basal nor terminal concentrations of leaves. Hydrophytic, or helophytic; when hydrophytic, rooted (sometimes forming mats). Leaves of aquatics emergent; minute to small; opposite (or clustered by suppression of internodes); ‘herbaceous’, or leathery, or membranous; petiolate; simple; epulvinate. Leaf blades entire; flat; linear, or obovate, or elliptic; pinnately veined. Mature leaf blades adaxially glabrous, or pubescent; abaxially glabrous, or pubescent. Leaves without stipules. Leaf blade margins entire. Leaves without a persistent basal meristem. Leaf anatomy. Hydathodes present (occasionally), or absent. Hairs present, or 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 solitary; axillary; pedicellate, or sessile; bracteate; ebracteolate; minute to small; very irregular; zygomorphic; 3–5 merous; tetracyclic. Free hypanthium absent. Hypogynous disk present. Perianth with distinct calyx and corolla (though rarely corolla rudimentary); 6–9; 2 -whorled; anisomerous. Calyx present; 3, or 4; 1 -whorled; gamosepalous; lobed. Calyx lobes markedly shorter than the tube. Calyx erect; imbricate, or valvate; campanulate; unequal but not bilabiate; green, or red, or brown; persistent; accrescent. Corolla present; 3–5; 1 -whorled; gamopetalous; lobed; imbricate, or valvate; bilabiate; with contrasting markings; white, or pink, or purple, or blue; not spurred. Androecium 2, or 4. Androecial members adnate (to the corolla); all equal (when only 2), or markedly unequal (when 4 present); free of one another; 1 -whorled. Stamens 2, or 4; becoming exserted, or remaining included; didynamous; reduced in number relative to the adjacent perianth (usually); oppositisepalous. Anthers centrifixed; dehiscing via longitudinal slits; introrse; unilocular (by confluence of 2 cells); tetrasporangiate. Gynoecium 2 carpelled. The pistil 2 celled. Gynoecium non-petaloid; syncarpous; eu-syncarpous; superior. Ovary plurilocular; 2 locular. Gynoecium median; stylate. Styles 1; attenuate from the ovary, or from a depression at the top of the ovary; apical. Stigmas 1; 1 - lobed (a prominent broad flap covering the mouth and anthers, receptive above, when touched quickly jerking back against the upper corolla lip), or 2 - lobed (vestigial second flap at base). 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; dehiscent; a capsule. Capsules loculicidal (with the septum remaining attached to the 2 valves). Fruit 50 seeded (to ‘many’). Seeds endospermic. Endosperm oily. Seeds minute. Cotyledons 2. Embryo straight to curved.

Special features. Corolla tube exceeding the calyx, or not exceeding the calyx; straight. The upper lip of the corolla incorporating 2 members, the lower 3; (posterior, adaxial) lip of the corolla bilobed (rarely reduced). Lower (abaxial) lip of the corolla 3 lobed (rarely reduced).

Geography, cytology, number of species. Native of Australia. Not endemic to Australia. Australian states and territories: Western Australia, South Australia, Northern Territory, Queensland, New South Wales, Victoria, Australian Capital Territory, and Tasmania. Northern Botanical Province and South-West Botanical Province.

Etymology. From the Greek for "tongue" and "stigma".