Dysphaniaceae (Pax) Pax
~ Amaranthaceae, Chenopodiaceae
Habit and leaf form. Small, prostrate herbs. ‘Normal’ plants. Annual to perennial; with neither basal nor terminal aggregations of leaves. Mesophytic, or xerophytic. Leaves small; alternate; petiolate; non-sheathing; simple; epulvinate. Lamina entire. Leaves exstipulate. Lamina margins entire, or crenate. Leaves without a persistent basal meristem.
Leaf anatomy. Stomata present; diacytic (?).
Stem anatomy. Secondary thickening developing from a conventional cambial ring, or anomalous; when anomalous, via concentric cambia. Sieve-tube plastids P-type; type III (c, without a crystal, cf. Chenopodiaceae).
Reproductive type, pollination. Plants gynomonoecious, or monoecious, or polygamomonoecious (?).
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in fascicles and in spikes. Inflorescences terminal, or axillary; fasciculate, or crowded and spicate. Flowers minute. Hypogynous disk absent.
Perianth sepaline; (1–)3–4; free, or joined (basally); 1 whorled; accrescent. Calyx (if perianth so interpreted) (1–)3–4; polysepalous, or gamosepalous (basally); persistent; accrescent (surrounding the fruit, becoming winged); valvate.
Androecium 1(–2). Androecial members free of the perianth; free of one another (exserted); 1 whorled. Androecium exclusively of fertile stamens. Stamens 1, or 2; reduced in number relative to the adjacent perianth to isomerous with the perianth; oppositisepalous. Anthers introrse. Pollen grains aperturate; 13–50 aperturate (?); (poly) foraminate.
Gynoecium (2–)3 carpelled. The pistil 1 celled. Gynoecium syncarpous; synovarious, or synstylovarious; superior. Ovary 1 locular. Styles 1, or 2; apical. Ovules in the single cavity 1; non-arillate; hemianatropous (?).
Fruit non-fleshy; indehiscent; a nut (surrounded by the broadly winged perianth). Seeds non-endospermic (?). Perisperm present (?). Embryo well differentiated. Embryo curved (‘circular, surrounding the endosperm’).
Seedling. Germination phanerocotylar.
Physiology, biochemistry. Anatomy non-C4 type (Dysphania).
Geography, cytology. Australia.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Caryophylliflorae; Caryophyllales. Cronquist’s Subclass Caryophyllidae; Caryophyllales. APG (1998) Eudicot; core Eudicot; neither Rosid nor Asterid; Caryophyllales (as a synonym of Amaranthaceae). Species 5. Genera 1; only genus, Dysphania.
Cite this publication as: ‘L. Watson and M. J. Dallwitz (1992 onwards). The Families of Flowering Plants: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 14th December 2000. http://biodiversity.uno.edu/delta/’. Dallwitz (1980), Dallwitz, Paine and Zurcher (1993, 1995, 2000), and Watson and Dallwitz (1991) should also be cited (see References).