Nuytsia G.Don

Scientific Description

Common name. Christmas Trees. Family Loranthaceae.

Habit and leaf form. Trees (small), or ‘arborescent’; evergreen. Leaves well developed, or much reduced (lower leaves of new shoots reduced to scales). Plants with roots (but these haustorial); partially parasitic. On roots of the host. Stem internodes solid (ass.). Stem growth conspicuously sympodial. Mesophytic, or xerophytic. Leaves alternate, or opposite (displaced), or whorled (rarely); somewhat fleshy, or leathery; sessile; edgewise to the stem, or with ‘normal’ orientation; simple. Leaf blades entire; linear (usually), or ovate; pinnately veined (penninerved); attenuate at the base. Leaves without stipules. Leaf blade margins entire. Leaves without a persistent basal meristem. Leaf anatomy. Hairs absent. Extra-floral nectaries absent (ass.). Stem anatomy. Secondary thickening anomalous; via concentric cambia.

Reproductive type, pollination. Fertile flowers functionally male and functionally female. Unisexual flowers present. Plants monoecious. The unisexual flowers not conspicuously in separate aggregates. Entomophilous, or ornithophilous.

Inflorescence and flower features. Flowers aggregated in ‘inflorescences’; in racemes. The terminal inflorescence unit cymose. Inflorescences terminal; inflorescence axis angular, raceme made of up to 50 pedunculate 3-flowered clusters, each with the central flower female and the lateral flowers male. Flowers pedicellate, or sessile; bracteate (1 under each flower, triangular, decurrent and persistent). Bracts persistent. Flowers bracteolate (2 close under each flower); regular to somewhat irregular. The floral asymmetry involving the perianth. Flowers cyclic. Floral receptacle markedly hollowed. Free hypanthium present (B); calyx tube adnate to the ovary. Perianth with distinct calyx and corolla; 3–9; 2 -whorled, or 1 -whorled. Calyx present (PBC), or vestigial (A); 2–4 (main lobes, unequal); 1 -whorled; gamosepalous; irregularly blunt-lobed, or toothed (6, unequal); open in bud; regular; persistent. Corolla present; 6–8; 1 -whorled; polypetalous; valvate; unequal but not bilabiate, or bilabiate, or regular; yellow (golden), or orange (to bright). Petals linear. Corolla members entire (ass.). Fertile stamens present, or absent. Androecial members definite in number. Androecium 6–8. Androecial members adnate (to the corolla); markedly unequal; free of one another (ass.); 1 -whorled. Androecium exclusively of fertile stamens. Stamens 6–8; all more or less similar in shape (ass.); isomerous with the perianth; alternisepalous (epipetalous, near base). Anthers dorsifixed; versatile; dehiscing via longitudinal slits; introrse; bilocular (at maturity), or four locular; bisporangiate, or tetrasporangiate. Gynoecium 3 carpelled, or 4 carpelled. The pistil 1 celled. Gynoecium syncarpous; synstylovarious, or eu-syncarpous; inferior. Ovary unilocular; 1 locular. Gynoecium stylate. Styles 1. Stigmas 1. Ovules not differentiated; in the single cavity 4–12; several; sessile; ascending; non-arillate; not clearly differentiated from the placenta.

Fruit and seed features. Fruit non-fleshy; indehiscent; a drupe, or a nut; 1 seeded. Seeds copiously endospermic. Endosperm oily. Seeds covered with viscous material; without a testa. Embryo well differentiated. Cotyledons 2, or 1.

Etymology. After Pieter Nuyts (?1600-?33), a member of the council of the Dutch East Indies who sailed along the south and west coasts of Australia in Gulde Zeepard 1627 and named the land Pieter Nuyts Land.