Loranthaceae Juss.
Including Dendrophthoaceae Van Tiegh., Dendrophthoraceae Dostál, Elytranthaceae Van Tiegh., Gaiadendraceae Van Tiegh., Lepidariaceae Van Tiegh., Nuytsiaceae Van Tiegh., Porosectaceae Dulac, Psittacanthaceae Nak., Treubaniaceae Van Tiegh., Treubellaceae Van Tiegh.
Excluding Eremolepidaceae
Habit and leaf form. Trees (Nuytsia), or lianas (a few), or shrubs (mostly ‘shrublets’). ‘Normal’ plants, or switch-plants (occasionally); switch forms with the principal photosynthesizing function transferred to stems. Leaves well developed, or much reduced (rarely). Plants rootless (in the normal sense), or with roots (but with haustoria rather than root-hairs, e.g. Nuytsia?); more or less succulent (in Nuytsia), or non-succulent; partially parasitic (with haustoria which often induce gall-like growth of hosts). On aerial parts of the host (mostly), or on roots of the host (a few). Stem growth conspicuously sympodial. Mesophytic, or xerophytic. Leaves evergreen; usually opposite; leathery (usually), or fleshy, or membranous (rarely); edgewise to the stem, or with ‘normal’ orientation; simple. Lamina entire; one-veined, or pinnately veined, or parallel-veined. Leaves exstipulate. Lamina margins entire. Leaves without a persistent basal meristem.
Leaf anatomy. Lamina dorsiventral, or isobilateral.
Stem anatomy. Cork cambium present; initially superficial. Nodes unilacunar. Internal phloem absent. Secondary thickening developing from a conventional cambial ring, or anomalous; when anomalous, via concentric cambia (Nuytsia). ‘Included’ phloem absent. Xylem with fibre tracheids, or without fibre tracheids; with libriform fibres, or without libriform fibres; with vessels. Vessel end-walls simple. Wood partially storied (VPI); parenchyma apotracheal, or apotracheal and paratracheal (typically predominantly apotracheal).
Reproductive type, pollination. Plants hermaphrodite (nearly always), or monoecious (Nuytsia, where the central flower of each triplet is female, the laterals male). Entomophilous, or ornithophilous.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in cymes, in racemes, in spikes, in fascicles, and in umbels. The terminal inflorescence unit cymose (the flowers often in threes). Inflorescences dichasial, the dichasia sometimes resembling racemes, spikes, umbels etc.. Flowers bracteolate (the two bracteoles adnate to form a ‘calyculus’ external to the calyx); regular to somewhat irregular. The floral irregularity involving the perianth. Flowers cyclic; tetracyclic. Floral receptacle markedly hollowed. Free hypanthium absent.
Perianth with distinct calyx and corolla, or petaline (the calyx much reduced, often to a mere rim), or absent (sometimes, in Amyema?); 3–9; 2 whorled, or 1 whorled (with the calyx obsolete). Calyx 1 whorled; gamosepalous (reduced to a lobed or toothed cup or rim); entire, or lobulate, or blunt-lobed, or toothed; regular; persistent; open in bud. Corolla (3–)5–6(–9); 1 whorled; polypetalous, or gamopetalous; valvate; often tubular (the tube often bent and split down one side); unequal but not bilabiate, or bilabiate, or regular; often yellow, or orange, or red.
Androecium (3–)5–6(–9) (as many as C). Androecial members adnate (to the corolla); free of one another; 1 whorled. Androecium exclusively of fertile stamens. Stamens (3–)5–6(–9); isomerous with the perianth; alternisepalous; opposite the corolla members. Anthers dehiscing via longitudinal slits; introrse; bisporangiate, or tetrasporangiate. Endothecium developing fibrous thickenings (usually), or not developing fibrous thickenings (Lepeostegeres). Anther epidermis degenerating. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or decussate. Anther wall initially with one middle layer, or initially with more than one middle layer; of the ‘monocot’ type. Pollen grains aperturate (usually), or nonaperturate (Atkinsonia); 3(–4) aperturate; colpate; 2-celled.
Gynoecium 3 carpelled, or 4 carpelled. The pistil 1 celled. Gynoecium syncarpous; synstylovarious, or eu-syncarpous; inferior. Ovary 1 locular. Placentation basal. Ovules not differentiated; in the single cavity 4–12; sessile; non-arillate; not clearly differentiated from the placenta; without integuments; without obvious nucellus. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating. Synergids hooked (with filiform apparatus). Endosperm formation cellular. Embryogeny piperad.
Fruit fleshy (usually), or non-fleshy (rarely, e.g. Nuytsia); indehiscent; usually a berry, or a drupe (the fleshy part being receptacular), or a nut (Nuytsia). Seeds copiously endospermic. Endosperm oily. Seeds covered with viscous material; without a testa. Embryo well differentiated. Cotyledons 2, or 1 (often becoming fused). Embryo chlorophyllous (2/2). Polyembryony recorded.
Seedling. Germination phanerocotylar, or cryptocotylar.
Physiology, biochemistry. Not cyanogenic. Alkaloids present, or absent. Iridoids not detected. Proanthocyanidins present; cyanidin. Flavonols present; kaempferol and quercetin. Ellagic acid present (Nuytsia). Saponins/sapogenins absent. Aluminium accumulation not found.
Geography, cytology. Temperate to tropical. Pantropical and warm (especially South) temperate. X = 8–12.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Santaliflorae; Santalales. Cronquist’s Subclass Rosidae; Santalales. APG (1998) Eudicot; core Eudicot; neither Rosid nor Asterid; Santalales. Species 940. Genera about 70; Actinanthella, Aetanthus, Agelanthus, Alepis, Amyema, Amylotheca, Atkinsonia, Bakerella, Baratranthus, Benthamina, Berhautia, Cecarria, Cladocolea, Cyne, Dactyliophora, Decaisnina, Dendropemon, Dendropthoe, Desmaria, Diplatia, Distrianthes, Elytranthe, Emelianthe, Englerina, Erianthemum, Gaiadendron, Globimetula, Helicanthes, Helixanthera, Ileostylus, Ixocactus, Kingella, Lampas, Lepeostegeres, Lepidaria, Ligaria, Loranthus, Loxanthera, Lysiana, Macrosolen, Moquiniella, Muellerina, Notanthera, Nuytsia, Oliverella, Oncella, Oncocalyx, Oryctanthus, Oryctina, Panamanthus, Papuanthes, Pedistylis, Peraxilla, Phragmanthera, Phthirusa, Plicosepalus, Psittacanthus, Scurrula, Septulina, Socratina, Sogerianthe, Spragueanella, Struthanthus, Tapinanthus, Taxillus, Tetradyas, Thaumasianthes, Tolypanthus, Trilepidea, Tripodanthus, Tristerix, Trithecanthera, Tupeia, Vanwykia.
Illustrations. • Technical details (Loranthus). • Technical details (Loranthus, Struthanthus). • Technical details (Loranthus).
Cite this publication as: ‘L. Watson and M. J. Dallwitz (1992 onwards). The Families of Flowering Plants: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 14th December 2000. http://biodiversity.uno.edu/delta/’. Dallwitz (1980), Dallwitz, Paine and Zurcher (1993, 1995, 2000), and Watson and Dallwitz (1991) should also be cited (see References).
