The Families of Flowering Plants
The Families of Flowering Plants | |
Including Drimyaceae Van Tiegh., Takhtajaniaceae (J. Leroy) J. Leroy
Habit and leaf form. Trees and shrubs; bearing essential oils. Mesophytic. Leaves alternate; spiral (rarely subverticillate); ‘herbaceous’, or leathery; petiolate; non-sheathing; gland-dotted; aromatic; simple; epulvinate. Lamina entire; pinnately veined; cross-venulate. Leaves exstipulate. Lamina margins entire. Leaves without a persistent basal meristem.
Leaf anatomy. Stomata paracytic. Hairs absent.
Lamina dorsiventral. The mesophyll with spherical etherial oil cells; with sclerencymatous idioblasts. Minor leaf veins without phloem transfer cells (Drimys). Vessels absent.
Stem anatomy. Cork cambium present; initially superficial. Nodes bilacunar (with three traces, according to Lammers et al. 1986), or tri-lacunar (?). Internal phloem absent. Secondary thickening developing from a conventional cambial ring. ‘Included’ phloem absent. Xylem presumably with tracheids; without vessels. Wood parenchyma apotracheal (diffuse or in fine lines, sometimes terminal). Sieve-tube plastids S-type.
Reproductive type, pollination. Plants hermaphrodite, or monoecious, or polygamomonoecious. Pollination anemophilous, or entomophilous.
Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in ‘inflorescences’; in cymes and in fascicles. The ultimate inflorescence unit cymose. Inflorescences cymes or fascicles. Flowers medium-sized; calyptrate, or not calyptrate; regular to somewhat irregular; cyclic (?); pentacyclic to polycyclic. Free hypanthium absent. Hypogynous disk absent.
Perianth with distinct calyx and corolla; (4–)7–50 (to ‘many’); 2–4 whorled; isomerous, or anisomerous. Calyx 2–4(–6); 1 whorled; polysepalous, or gamosepalous (then the sepals basally connate or totally concrescent); unequal but not bilabiate, or regular; not persistent; calyptrate, or not calyptrate; valvate. Corolla (2–)5–50; 1–3 whorled; polypetalous, or partially gamopetalous (the outer whorl sometimes joined); imbricate; unequal but not bilabiate, or regular.
Androecium 15–100 (to ‘many’). Androecial members maturing centrifugally (but initiated centripetally); free of the perianth; free of one another; 2–5 whorled. Androecium exclusively of fertile stamens. Stamens 15–100; laminar (often), or filantherous. Anthers adnate; non-versatile; dehiscing via longitudinal slits; extrorse, or latrorse, or introrse (sometimes the ‘sides’ of the thecae directed apically); tetrasporangiate. Endothecium developing fibrous thickenings. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or isobilateral, or decussate. Anther wall initially with more than one middle layer (2 to 4); of the ‘basic’ type. Tapetum amoeboid, or glandular. Pollen shed in aggregates, or shed as single grains; usually in tetrads. Pollen grains aperturate; 1 aperturate; ulcerate; 2-celled.
Gynoecium (1–)3–20 carpelled (in one whorl). The pistil when other than apocarpous, 1 celled, or 2–20 celled. Gynoecium monomerous, or apocarpous, or syncarpous; of one carpel (sometimes), or eu-apocarpous, or semicarpous, or synovarious (i.e. carpels free, or partly or wholly connate); superior. Carpel (when monomeric/apocarpous) fully closed, or incompletely closed; non-stylate, or stylate; with a longitudinal stigmatic surface, or apically stigmatic; 1–100 ovuled (to ‘many’). Placentation marginal, or dispersed. Ovary (when more or less syncarpous) 2–20 locular. Stigmas 2–20; wet type; papillate; Group III type. Placentation when syncarpous, axile. Ovules 1–50 per locule; non-arillate; anatropous; bitegmic; crassinucellate. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating; persistent. Synergids hooked (with filiform apparatus). Endosperm formation cellular.
Fruit fleshy, or non-fleshy; an aggregate, or not an aggregate. The fruiting carpels when compound coalescing into a secondary syncarp, or not coalescing. The fruiting carpel dehiscent, or indehiscent; a follicle, or baccate. Fruit when syncarpous dehiscent, or indehiscent; a capsule, or a berry. Seeds copiously endospermic. Endosperm not ruminate; oily. Embryo well differentiated (but very small).
Seedling. Germination phanerocotylar.
Physiology, biochemistry. Cyanogenic, or not cyanogenic. Alkaloids present, or absent. Iridoids not detected. Proanthocyanidins present; cyanidin. Flavonols present; quercetin. Ellagic acid absent. Anatomy non-C4 type.
Geography, cytology. Temperate to tropical. Malaysia to the Pacific, Eastern Australia, New Zealand, Central and South America. X = 13, 43.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Magnoliiflorae; Magnoliales. Cronquist’s Subclass Magnoliidae; Magnoliales. APG 3 Order Canellales.
Species 120. Genera 9; Drimys, Belliolum, Bubbia, Exospermum, Pseudowintera, Takhtajania, Tasmannia, Tetrathalamus, Zygogynum.
Illustrations. • Technical details: Drimys.
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’.
