Family Neuradaceae

Neuradaceae J.G. Agardh

Habit and leaf form. Densely pubescent prostrate herbs (with sympodial stems). Plants non-succulent. Annual. Leaves alternate; simple. Lamina dissected, or entire; when deeply dissected, pinnatifid (or pinnately lobed). Leaves stipulate and exstipulate. Lamina margins when the leaf not deeply dissected, serrate, or dentate.

Leaf anatomy. Stomata present; anomocytic.

Stem anatomy. Cortical bundles absent. Medullary bundles absent. Internal phloem absent. Secondary thickening developing from a conventional cambial ring, or absent (?). Vessel end-walls simple. Vessels without vestured pits.

Reproductive type, pollination. Plants hermaphrodite.

Inflorescence, floral, fruit and seed morphology. Flowers solitary (upturned, on horizontally spreading, seemingly axillary peduncles); regular; 5 merous; cyclic; pentacyclic. Free hypanthium present.

Perianth with distinct calyx and corolla; 10; 2 whorled; isomerous. Calyx 5; 1 whorled; polysepalous; regular; valvate. Epicalyx present (sometimes, of five bracteoles), or absent. Corolla 5; 1 whorled; polypetalous; imbricate, or contorted.

Androecium 10. Androecial members free of the perianth (borne on the slightly prolonged hypanthium); free of one another; 2 whorled (5+5). Androecium exclusively of fertile stamens. Stamens 10; diplostemonous; both alternating with and opposite the corolla members; filantherous (the filaments subulate, persistent). Anthers dorsifixed; versatile; dehiscing via longitudinal slits; introrse; tetrasporangiate. Pollen shed as single grains. Pollen grains aperturate; (6–)8 aperturate; uniquely aperturate, being bipolar with (3–4 pores at each end; 2-celled.

Gynoecium 10 carpelled (by dedoublement from five?). Carpels increased in number relative to the perianth. The pistil if other than apocarpous, (6–)10 celled. Gynoecium monomerous to syncarpous; semicarpous, or synovarious (the carpels dorsally adnate to the hypanthium, but ventrally free); partly inferior to inferior. Ovary if regarded as syncarpous, (6–)10 locular (with 2–4 of the locules on the side towards the peduncle more or less reduced, or their ovules abortive). Gynoecium stylate. Styles (3–)6–10; free (becoming indurated). Stigmas (3–)6–10; capitate. Placentation axile to apical. Ovules 1 per locule; pendulous; apotropous; non-arillate; anatropous; bitegmic; crassinucellate.

Fruit non-fleshy. The fruiting carpel (if the individual carpels are viewed as separate units) dehiscent; a follicle (one-seeded). Fruit (viewing it as a syncarp) dehiscent; a capsule (with ventrally dehiscent carpels — i.e., representing one-seeded follicles sunk in the hardened receptacle and associated structures). Seeds non-endospermic. Perisperm absent. Embryo well differentiated. Cotyledons 2.

Seedling. Germination phanerocotylar.

Geography, cytology. Holarctic and Paleotropical. Temperate to sub-tropical. Mediterranean to India. N = 6.

Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Rosiflorae; Rosales. Cronquist’s Subclass Rosidae; Rosales. APG 3 core angiosperms; core eudicot; Superorder Rosanae; malvid; Order Malvales.

Species 10. Genera 3; Grielum, Neurada, Neuradopsis.