The Families of Flowering Plants
The Families of Flowering Plants |
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~ Celastraceae
Habit and leaf form. Herbs. ‘Normal’ plants, or switch-plants. Leaves well developed, or much reduced. Plants succulent, or non-succulent. Annual, or perennial; perennials rhizomatous. Mesophytic, or xerophytic. Leaves alternate; spiral; ‘herbaceous’, or leathery, or fleshy, or membranous; petiolate to sessile; non-sheathing; simple; epulvinate. Lamina entire; linear, or lanceolate, or oblanceolate; one-veined, or pinnately veined. Leaves inconspicuously stipulate. Stipules interpetiolar; scaly (or terete); caducous (usually?), or persistent. Lamina margins entire.
Leaf anatomy. Stomata present; anomocytic.
Lamina dorsiventral, or isobilateral, or centric. The mesophyll without calcium oxalate crystals.
Stem anatomy. Secondary thickening developing from a conventional cambial ring (?). Xylem with fibre tracheids. Vessel end-walls simple.
Reproductive type, pollination. Unisexual flowers absent. Plants hermaphrodite.
Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in ‘inflorescences’; in cymes, or in racemes, or in umbels. The ultimate inflorescence unit cymose, or racemose. Inflorescences racemes or cymes, rarely umbellate. Flowers bracteate; bracteolate (usually, with two bracteoles), or ebracteolate; fragrant (mostly?), or odourless; regular to somewhat irregular. The floral irregularity involving the androecium. Flowers 5 merous; cyclic; tetracyclic. Free hypanthium present. Hypogynous disk present (lining the floral tube).
Perianth with distinct calyx and corolla; 10; 2 whorled; isomerous. Calyx 5; 1 whorled; polysepalous (on the hypanthium), or gamosepalous (towards the base above the hypanthium); regular, or unequal but not bilabiate; imbricate. Corolla 5; 1 whorled; polypetalous, or gamopetalous; imbricate; unequal but not bilabiate, or regular; white, or yellow, or pink, or purple. Petals clawed (the claws free, even when gamopetalous above).
Androecium 5. Androecial members free of the perianth; markedly unequal (usually three long, two short), or all equal (Macgregoria); free of one another; 1 whorled. Androecium exclusively of fertile stamens. Stamens 5; isomerous with the perianth; oppositisepalous; alternating with the corolla members. Anthers dehiscing via longitudinal slits; tetrasporangiate; appendaged (Macgregoria), or unappendaged. The anther appendages apical. Endothecium developing fibrous thickenings. Anther epidermis persistent. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or isobilateral, or decussate. Anther wall initially with one middle layer. Tapetum glandular. Pollen grains aperturate; 3 aperturate; colporate; 3-celled.
Gynoecium (2–)3(–5) carpelled. Carpels reduced in number relative to the perianth to isomerous with the perianth. The pistil (2–)3(–5) celled. Gynoecium syncarpous; synovarious to eu-syncarpous; superior. Ovary (2–)3(–5) locular. Gynoecium stylate. Styles 1, or 2–5; free, or partially joined; attenuate from the ovary, or from a depression at the top of the ovary; apical. Stigmas 2–5. Placentation axile to basal. Ovules 1 per locule; ascending; apotropous; with ventral raphe; anatropous; bitegmic; tenuinucellate. Outer integument contributing to the micropyle. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3 (sometimes multinucleate); proliferating (to form 10–15 cells), or not proliferating. Synergids pear-shaped. Hypostase present. Endosperm formation nuclear. Embryogeny asterad.
Fruit non-fleshy; a schizocarp. Mericarps (2–)3(–5); comprising nutlets, or samaroid. Fruit 2–5 seeded. Seeds endospermic. Endosperm oily. Cotyledons 2. Embryo straight.
Seedling. Germination phanerocotylar.
Physiology, biochemistry. Not cyanogenic. Iridoids not detected. Proanthocyanidins present. Aluminium accumulation not found.
Geography, cytology. Temperate to tropical. Malaysia, Australia, New Zealand. X = 9, 10, 15.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Santaliflorae; Celastrales. Cronquist’s Subclass Rosidae; Celastrales. APG 3 core angiosperms; core eudicot; Superorder Rosanae; fabid; Order Celastrales (as a synonym of Celastraceae).
Species 27. Genera 3; Macgregoria, Stackhousia, Tripterococcus.
Illustrations. • Technical details: Stackhousia, Tripterococcus. • Stackhousia monogyna, habit and inflorescence. • Stackhousia monogyna: Bot. Reg. 1917 (1836).
This description is offered for casual browsing only. We strongly advise against extracting comparative information from it. This is much more easily achieved using the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting specified attributes, summaries of attributes within groups of taxa, geographical distribution, genera included in each family, classifications (Dahlgren; Dahlgren, Clifford, and Yeo; Cronquist; APG), and notes on the APG classification.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 25th November 2009. http://delta-intkey.com’.
