Spirogardnera Stauffer

Scientific Description

Family Santalaceae.

Habit and leaf form. Shrubs. More or less ‘normal’ plants, or switch-plants; with the principal photosynthesizing function transferred to stems. Leaves well developed, or much reduced. Plants with roots, or rootless; partially parasitic. On roots of the host, or on aerial parts of the host. Young stems cylindrical (branchlets). Stem internodes solid. Mesophytic, or xerophytic. Leaves alternate; ‘herbaceous’, or membranous, or modified into spines; petiolate to sessile; gland-dotted, or not gland-dotted; aromatic, or without marked odour; simple; pulvinate. Leaf blades entire; linear; one-veined, or pinnately veined. Leaves without stipules. Leaf blade margins entire. Leaf anatomy. Hairs absent. Extra-floral nectaries absent. Stem anatomy. Secondary thickening developing from a conventional cambial ring.

Reproductive type, pollination. Fertile flowers hermaphrodite. Unisexual flowers absent. Plants hermaphrodite.

Inflorescence and flower features. Flowers aggregated in ‘inflorescences’; in spikes (or spike-like), or in fascicles (or small clusters). The terminal inflorescence unit cymose, or racemose. Inflorescences terminal; inflorescences twisted. Flowers pedicellate (very short); bracteate (C), or ebracteate (A); ebracteolate; small; regular; (4–)5 merous; cyclic; tricyclic. Free hypanthium present, or absent; KPB describe the floral tube in the Santalaceae but without reference to Spirogardnera. Perianth sepaline; (4–)5; 1 -whorled; free, or joined; sepaloid, or petaloid; white, or red; fleshy, or non-fleshy; persistent. Calyx (‘calycode’) (4–)5; 1 -whorled; gamosepalous; valvate; regular; white, or red (turning red); fleshy, or non-fleshy; persistent. Calyx lobes triangular. Androecial members definite in number. Androecium 4–5. Androecial members free of the perianth, or adnate; all equal; free of one another; 1 -whorled. Androecium exclusively of fertile stamens. Stamens (4–)5; all more or less similar in shape; isomerous with the perianth; oppositisepalous (opposite the perianth lobes and at their bases). Anthers dorsifixed (A), or basifixed (L); dehiscing via longitudinal slits; introrse; bilocular; tetrasporangiate. Gynoecium (4–)5 carpelled. The pistil 1 celled. Carpels reduced in number relative to the perianth to isomerous with the perianth. Gynoecium syncarpous; synstylovarious, or eu-syncarpous; inferior. Ovary unilocular; 1 locular (at least above). Epigynous disk present. Gynoecium stylate. Styles 1; apical. Stigmas 1; 5 - lobed; capitate (or lobed). Placentation basal, or free central. Ovules differentiated to not differentiated; in the single cavity 3–5; pendulous; hemianatropous to anatropous.

Fruit and seed features. Fruit fleshy, or non-fleshy; indehiscent; a drupe, or a nut; (4–)5 seeded. Seeds endospermic. Endosperm oily, or not oily. Seeds without a testa. Cotyledons 2.

Etymology. From the Greek for "anything twisted or coiled" and Charles Austin Gardner (1896–1970), government botanist, Western Australia; the plant was named for C. A. Gardner but, as another genus Gardneria existed, the prefix was added on account of the spiral arrangement of the inflorescence.