Hydrophyllaceae

Abstract

Annual, biennial or perennial herbs, subshrubs, shrubs, rarely small trees (Wigandia), often aromatic; primary root usually persistent and developed as strong taproot, sometimes roots tuberous; stems erect, rarely prostrate to ascending, sometimes forming simple or few- to many-branched rhizomes; indumentum usually present and strongly developed on whole plant, usually scabrid to hispid, often densely glandular, sometimes distinct stinging hairs present. Leaves alternate or opposite, basal and/or cauline, exstipulate, lamina linear, narrowly ovate to subcircular, simple to compound, margins entire or variously lobed, sessile to petiolate. Inflorescences terminal or axillary, frondose, bracteose or ebracteose, paraclades monochasial or dichasial, lax or very dense, usually scorpioid and contracted into boragoids, these paraclades present as simple terminal inflorescences or combined into complex thyrsoids, sometimes with extensive accessory paraclades; sometimes inflorescences congested into terminal “heads”, or strongly reduced to axillary or terminal single flowers. Flowers pentamerous, usually hypogynous, bisexual, commonly protandrous; perianth biseriate, sepals united at base or nearly to apex, usually radially symmetrical, sometimes slightly or distinctly unequal with some lobes much larger than others, with or without appendages between the lobes, persistent and usually accrescent in fruit, spreading or closing; corolla sympetalous, mostly campanulate, more rarely rotate or infundibuliform, tube internally often with scales, glands or hair lines near base of each filament; lobes spreading or porrect, rarely reflexed, narrowly triangular to (usually) oblong or subcircular; aestivation usually quincuncial, rarely contorted; stamens epipetalous and antesepalous, inserted at the same or at different heights in corolla tube, anthers included or exserted, free from each other, dorsifixed, dithecous, tetrasporangiate, opening by longitudinal slits; gynoecium 2-carpellate, syncarpous, superior to half-inferior, pubescent, often glandular, usually with basal nectar disk; stylodia 2 or connate into a usually bifid or deeply bifurcate, rarely entire, slender style; stigma punctate or capitate, dry; ovules (1–)4–∞, anatropous, unitegmic, tenuinucellate; placentation parietal or intrusive-parietal. Fruits 1- to many-seeded capsules, 2–4-valved, with loculicidal or loculicidal and septicidal dehiscence, rarely indehiscent. Seeds ovoid, globose or angular, with dark, often reticulate testa, endosperm copious, oily, rarely with elaiosome; embryo small, straight.