Family Thymelaeaceae
Thymelaeaceae Juss.Including Daphnoideae (Daphnaceae) Vent., Phalerieae (Phaleriaceae) Meissn.Excluding Aquilariaceae, Gonystylaceae Habit and leaf form. Shrubs (most), or shrubs, or lianas (rarely), or herbs (rarely). Plants non-succulent. Self supporting (usually), or climbing. Mesophytic, or xerophytic. Leaves small to medium-sized; alternate, or opposite, or whorled; commonly spiral; flat, or rolled; ‘herbaceous’, or leathery (sometimes ericoid); petiolate to sessile; gland-dotted, or not gland-dotted; simple. Lamina entire; pinnately veined; cross-venulate. Leaves exstipulate; without a persistent basal meristem. General anatomy. Plants with ‘crystal sand’, or without ‘crystal sand’. Leaf anatomy. Mucilaginous epidermis present. Stomata anomocytic, or cyclocytic. Adaxial hypodermis present (of mucilaginous cells, in Daphne), or absent. Lamina dorsiventral, or isobilateral, or centric. The mesophyll with sclerencymatous idioblasts, or without sclerenchymatous idioblasts. Minor leaf veins without phloem transfer cells (Daphne, Pimelea). Stem anatomy. Cork cambium present; initially superficial. Nodes unilacunar. Primary vascular tissue bicollateral, or centrifugal. Internal phloem present (in nearly all the genera), or absent (e.g. Drapetes). Secondary thickening developing from a conventional cambial ring, or anomalous; when anomalous, via concentric cambia (Wikstroemia), or from a single cambial ring. ‘Included’ phloem present (commonly), or absent. Xylem with fibre tracheids; with libriform fibres, or without libriform fibres; with vessels. Vessel end-walls simple. Vessels with vestured pits (usually), or without vestured pits (then vestures confined to fibre pits, e.g. in Dirca, Daphne, Wikstroemia). Wood parenchyma paratracheal (and often with terminal bands). Reproductive type, pollination. Plants hermaphrodite, or monoecious, or dioecious, or gynodioecious (with much variation in Pimelea). Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in ‘inflorescences’; in racemes, or in heads, or in fascicles. The ultimate inflorescence unit racemose. Inflorescences racemes or heads, very condensed; with involucral bracts (often), or without involucral bracts; pseudanthial, or not pseudanthial. Flowers bracteolate, or ebracteolate; regular to somewhat irregular; 4–5 merous; cyclic. Floral receptacle with neither androphore nor gynophore; markedly hollowed (often forming a deep tube of leafy consistency). Free hypanthium nearly always conspicuously present (but ‘more or less absent’ in Synandrodaphne). Hypogynous disk present, or absent; when present, of separate members, or annular. Perianth with distinct calyx and corolla, or sepaline (the corolla sometimes missing or interpretable as staminodes, then the ‘calyx’ commonly more or less petaloid); 4–5, or 8–10, or 11–17; 2 whorled, or 1 whorled; isomerous, or anisomerous. Calyx 4–5; 1 whorled; gamosepalous (usually, variously laciniate or represented by lobes on the hypanthium), or polysepalous (rarely); unequal but not bilabiate, or regular; (tube) persistent; imbricate. Corolla when present, (3–)4–5(–12) (scale-like); 1 whorled; not appendiculate; polypetalous (inserted on the hypanthial tube or at its mouth); imbricate. Androecium 2 (rarely — Pimelea), or 4–5, or 8, or 10, or 11–100 (usually the same number as the calyx lobes, sometimes double them or ‘many’). Androecial members branched (?), or unbranched; free of the perianth (at the mouth of the hypanthium), or adnate (to ‘calyx tube’); free of one another; 1 whorled (when 4–5), or 2 whorled (when 8 or 10). Androecium exclusively of fertile stamens, or including staminodes (depending on interpretation). Staminodes if so interpreted, 3–12; petaloid (the scalelike ‘petals’ being interpretable as staminodes). Stamens 2, or 4, or 5, or 8, or 10, or 11–35; reduced in number relative to the adjacent perianth (rarely), or isomerous with the perianth, or diplostemonous, or polystemonous; oppositisepalous (when one whorled), or alternisepalous (when 2 whorled?); filantherous, or with sessile anthers. Anthers dehiscing via longitudinal slits; introrse; tetrasporangiate. Endothecium developing fibrous thickenings. Anther epidermis persistent. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or isobilateral. Anther wall initially with one middle layer, or initially with more than one middle layer (1 or 2); of the ‘monocot’ type. Tapetum glandular. Pollen grains aperturate; (3–)4–30 aperturate (to ‘many’); (oligo- to poly-) foraminate; 3-celled (in 5 genera). Gynoecium 2–5(–12) carpelled. Carpels isomerous with the perianth, or reduced in number relative to the perianth, or increased in number relative to the perianth. The pistil 1 celled, or 2–5 celled. Gynoecium syncarpous (but occasionally pseudomonomerous when G2); eu-syncarpous; superior. Ovary 1 locular (occasionally, when G2), or 2–5 locular, or 2 locular. Gynoecium non-stylate, or stylate. Styles 1 (the simple style sometimes with small ‘parastyles’ at the base); apical, or lateral. Stigmas dry type; papillate; Group II type. Placentation when unilocular parietal, or apical; when plurilocular (i.e.usually) axile, or apical. Ovules in the single cavity when unilocular, 1; 1 per locule; pendulous; epitropous; with ventral raphe; arillate (or carunculate); anatropous, or hemianatropous; bitegmic; crassinucellate. Outer integument not contributing to the micropyle. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; proliferating (usually, forming up to 30 or more cells), or not proliferating. Synergids hooked (sometimes with filiform apparatus). Hypostase usually present. Endosperm formation nuclear. Embryogeny asterad. Fruit fleshy, or non-fleshy; indehiscent; achene-like, or a berry, or a drupe. Seeds endospermic, or non-endospermic; with a testa. Cotyledons 2. Embryo achlorophyllous (2/3); straight. Seedling. Germination phanerocotylar, or cryptocotylar. Physiology, biochemistry. Not cyanogenic. Alkaloids present, or absent. Iridoids not detected. Proanthocyanidins absent (mostly), or present; cyanidin (in one Daphne sample). Flavonols present, or absent; quercetin, or kaempferol and quercetin. Ellagic acid absent (5 species, 2 genera). Arbutin absent. Aluminium accumulation not found. Sugars transported as sucrose (in Daphne). C3. C3 physiology recorded directly in Thymelaea. Anatomy non-C4 type (Daphne, Dendrostelleria, Thymelaea). Geography, cytology. Temperate to tropical. Very widespread, tropical to temperate - more diverse in the Southern hemisphere. X often = 9. Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Malviflorae; Thymelaeales. Cronquist’s Subclass Rosidae; Myrtales. APG 3 core angiosperms; core eudicot; Superorder Rosanae; malvid; Order Malvales. Species 500. Genera 44; Aetoxylon, Amyxa, Arnhemia, Atemnosiphon, Craterosiphon, Cryptadenia, Dais, Daphne, Daphnemorpha, Daphnopsis, Deltaria, Diarthron, Dicranolepis, Dirca, Drapetes, Edgeworthia, Enkleia, Eriosolena, Funifera, Gnidia, Goodallia, Jedda, Kelleria, Lachnaea, Lagetta, Lasiadenia, Lasiosiphon, Lethedon, Linodendron, Linostoma, Lophostoma, Oreodendron, Ovidia, Passerina, Peddiea, Phaleria, Pimelea, Rhamnoneuron, Schoenobiblus, Stellera, Stephanodaphne, Struthiola, Synandrodaphne, Synaptolepis, Thecanthes, Thymelaea, Wikstroemia. Gonystylaceae are excluded with good reason. Economic uses, etc. Cultivated ornamental shrubs from Daphne, Dais, Dirca (leatherwood), Pimelea (rice flower), etc.; incense, from Wikstroemia; bark fibre for paper from Daphne, Edgeworthia, Thymelaea, etc. Illustrations. |
Support our developers
