Resedaceae Martinov

Scientific Description

Common name. Mignonette Family.

Habit and leaf form. Herbs (mostly), or shrubs (a few). Annual, or biennial, or perennial; plants with a basal concentration of leaves, or with neither basal nor terminal concentrations of leaves. Mesophytic, or xerophytic. Leaves alternate; spiral; petiolate to sessile; non-sheathing; simple; epulvinate. Leaf blades dissected (sometimes deeply so), or entire; when dissected pinnatifid, or palmately lobed (sometimes trifid); one-veined, or pinnately veined. Leaves with stipules. Stipules intrapetiolar; free of one another; represented by glands. Leaves without a persistent basal meristem. Stem anatomy. Nodes unilacunar. Secondary thickening absent, or developing from a conventional cambial ring.

Reproductive type, pollination. Fertile flowers hermaphrodite, or functionally male. Unisexual flowers present (rarely), or absent. Plants hermaphrodite (usually), or androdioecious (sometimes, by abortion, in Ochradenus).

Inflorescence and flower features. Flowers aggregated in ‘inflorescences’; in racemes and in spikes. The terminal inflorescence unit racemose. Inflorescences racemes and spikes. Flowers bracteate; ebracteolate; small to medium-sized; very irregular. The floral asymmetry involving the perianth and involving the androecium. Floral receptacle developing an androphore (usually, with the extra-staminal disk more strongly developed posticously), or with neither androphore nor gynophore. Free hypanthium absent. Perianth with distinct calyx and corolla, or sepaline (petals sometimes lacking); (4–)12(–16); 2 -whorled (usually), or 1 -whorled; anisomerous (often), or isomerous (sometimes?). Calyx (4–)6(–8); 1 -whorled; polysepalous, or gamosepalous (sometimes more or less connate below); imbricate (slightly), or valvate; unequal but not bilabiate (sometimes), or regular; persistent. Corolla when present, (2–)6(–8); 1 -whorled; polypetalous (usually), or gamopetalous (rarely connate); valvate, or with open aestivation; with the outer members usually progressively smaller and with fewer appendages; white, or yellow; persistent, or deciduous. Petals clawed (usually, broadly so, with scalelike appendages). Corolla members fringed, or deeply bifid (at least the innermost largest, usually). Fertile stamens present, or absent (female flowers). Androecium 3–50 (or more — the number very indefinite). Androecial sequence determinable, or not determinable. Androecial members theoretically maturing centrifugally; free of the perianth; markedly unequal (the posterior members usually shorter), or all equal; free of one another (usually), or coherent; in Oligomeris, 1 - adelphous. Androecium exclusively of fertile stamens. Stamens 3–50 (or more); isomerous with the perianth to polystemonous. Anthers dehiscing via longitudinal slits; introrse; tetrasporangiate. Fertile gynoecium present, or absent (male flowers). Gynoecium (2–)3–6(–7) carpelled. The pistil 1 celled. Gynoecium apocarpous to syncarpous; eu-apocarpous (Sesamoides), or semicarpous (Caylusea), or synovarious (usually); superior. Carpel in Sesamoides and Caylusea incompletely closed; in Sesamoides 1(–2) ovuled. Placentation in Sesamoides basal. Ovary unilocular; usually syncarpous and 1 locular. The ‘odd’ carpel posterior. Gynoecium non-stylate. Stigmas (2–)3–6(–7); commissural, or dorsal to the carpels and commissural; dry type; non-papillate; Group II type. Placentation parietal (usually), or basal (Caylusia). Ovules in the single cavity 5–100 (‘few to many’); pendulous, or ascending; with ventral raphe; arillate, or non-arillate; hemianatropous, or campylotropous.

Fruit and seed features. Fruit fleshy, or non-fleshy; an aggregate (sometimes, the carpels spreading), or not an aggregate. The fruiting carpel of Sesamoides a follicle. Fruit indehiscent; capsular-indehiscent (but apically open), or a berry. Seeds more or less non-endospermic; reniform. Embryo well differentiated; chlorophyllous (2 species of Reseda); curved, or bent. Seedling. Germination phanerocotylar.

Physiology, biochemistry. Mustard-oils present. Aluminium accumulation not found. Photosynthetic pathway: C₃.

Special features. The young, syncarpous unilocular gynoecium and later the capsule open (usually), or gynoecium and fruit not as in Resedaceae.

Geography, cytology, number of species. World distribution: Southwest Eurasia, Mediterranean, North Africa and Middle East, South Africa, Southwest U.S.A. and Mexico. X = 6–15. 70 species.