Achariaceae Harms
Excluding currently about a dozen genera long referred to Flacourticeae (q.v.)
Habit and leaf form. Shrubs, or herbs; non-laticiferous and without coloured juice. Herbs with a basal aggregation of leaves, or with neither basal nor terminal aggregations of leaves. Self supporting (or stemless), or climbing. Leaves alternate; non-sheathing; simple. Lamina dissected (lobed), or entire; sometimes acicular. Leaves exstipulate. Lamina margins crenate, or serrate.
Stem anatomy. Cork cambium present; initially superficial. Vessel end-walls mostly simple.
Reproductive type, pollination. Fertile flowers functionally male and functionally female. Plants monoecious. Gynoecium of male flowers absent. |
Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in ‘inflorescences’ (few flowered); in fascicles and in racemes. The ultimate inflorescence unit (when determinable) racemose. Inflorescences few flowered, in fascicles or racemes. Flowers small to medium-sized; regular; 3–5 merous.
Perianth with distinct calyx and corolla; 6–10; 2 whorled. Calyx 3–5; 1 whorled; gamosepalous (at the base). Calyx lobes markedly longer than the tube. Calyx open in bud. Corolla 3–5; 1 whorled; gamopetalous. Degree of gamopetaly 0.75 (with a campanulate tube). Corolla valvate; regular.
Androecium in male flowers, 6–10. Androecial members adnate; markedly unequal (the staminodes shorter); free of one another; 2 whorled. Androecium of male flowers including staminodes. Staminodes 3–5 (short, fleshy); internal to the fertile stamens. Stamens 3–5; inserted near the base of the corolla tube, or midway down the corolla tube to in the throat of the corolla tube; isomerous with the perianth; oppositisepalous (the fertile members alternating with the petals). Anthers basifixed (the connective broadly expanded); non-versatile; dehiscing via longitudinal slits; introrse. Pollen grains aperturate; 3 aperturate; colporate.
Gynoecium in female flowers 3–5 carpelled. The pistil 1 celled. Gynoecium syncarpous; synovarious to synstylovarious; superior. Ovary 1 locular; sessile. Styles attenuate from the ovary; apical; shorter than the ovary. Stigmas 3–5. Placentation parietal (with 3–5 placentas). Ovules in the single cavity 3–20; arillate.
Fruit non-fleshy; dehiscent. Dispersal unit the seed. Seeds endospermic. Embryo well differentiated. Cotyledons 2. Embryo straight; small.
Physiology, biochemistry. Aluminium accumulation not found.
Geography, cytology. Paleotropical and Cape. South Africa.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Violiflorae; Violales. Cronquist’s Subclass Dilleniidae; Violales. APG (1998) Eudicot; core Eudicot; Rosid; Eurosid I. APG 3 (2009) Order: Malpighiales.
Species 3. Genera 3; Acharia, Ceratiosicyos, Guthriea.
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