The families of flowering plants.
IncludingOchranthaceae (Lindl.) Endl., Simabaceae Horan. (p.p.)Excluding Tapisciaceae (Pax) Takhtajan
Habit and leaf form. Small trees, or shrubs.Leaves opposite; petiolate; not gland-dotted; without marked odour; ostensibly simple (at least sometimes, in Turpinia), or compound (generally, at least basically); pulvinate; when recognisably compound, unifoliolate (in some Turpinia species?), or ternate (often), or pinnate. Lamina pinnately veined; cross-venulate. Leavesstipulate. Stipules caducous. Lamina margins usually serrate, or dentate.
Leaf anatomy. Mucilaginous epidermis present, or absent. Stomata present; anisocytic. Hairs present; eglandular.
Lamina dorsiventral. The mesophyll containing calcium oxalate crystals. The mesophyll crystals druses. Minor leaf veins without phloem transfer cells (Staphylea).
Stem anatomy. Cork cambium present; initially superficial. Nodes tri-lacunar. Secondary thickening developing from a conventional cambial ring. Xylem with tracheids, or without tracheids; with fibre tracheids; with vessels. Vessel end-walls oblique; scalariform. Wood parenchyma scanty paratracheal.
Reproductive type, pollination. Plants hermaphrodite, or monoecious, or dioecious, or polygamomonoecious.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in racemes, or in panicles. Inflorescences terminal, or axillary; drooping panicles or racemes. Flowers bracteate; small; regular; not resupinate; 5 merous; cyclic. Free hypanthium absent. Hypogynous disk present; intrastaminal.
Perianthwith distinct calyx and corolla; 10; 2 whorled; isomerous; sepaloid and petaloid, or petaloid. Calyx 5 (often petaloid); 1 whorled; more or less polysepalous (never forming a tube); regular; imbricate. Corolla 5; 1 whorled; polypetalous; imbricate; regular.
Androecium 5. Androecial members free of the perianth; all equal; free of one another; 1 whorled. Androecium exclusively of fertile stamens. Stamens 5; isomerous with the perianth; oppositisepalous; alternating with the corolla members; filantherous (the filaments sometimes very flattened). Anthers dorsifixed; versatile; dehiscing via longitudinal slits; introrse; tetrasporangiate. Endothecium developing fibrous thickenings. Anther epidermis persistent. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral. Anther wall initially with one middle layer. Tapetum glandular. Pollen shed as single grains. Pollen grains aperturate; (2–)3 aperturate, or 4–12 aperturate; colporate, or rugate; 2-celled (Staphylea), or 3-celled (Turpinia).
Gynoecium 2–3(–4) carpelled. Carpels reduced in number relative to the perianth. The pistil when syncarpous (i.e. usually), 2–3(–4) celled. Gynoecium apocarpous (Euscaphis), or apocarpous to syncarpous, or syncarpous; eu-apocarpous (Euscaphis only), or semicarpous to eu-syncarpous (the carpels variously partially separate or separating); superior to partly inferior (the base often embedded in the disk). Carpel of the apocarpous Euscaphis stylate; apically stigmatic; (1–)6–12 ovuled. Ovary usually syncarpous and 2–3(–4) locular. Gynoecium stylate. Styles 1, or 2–3(–4); free, or partially joined (sometimes joined distally); attenuate from the ovary, or from a depression at the top of the ovary; apical. Stigmas wet type; papillate; Group IV type. Placentation axile, or basal to axile. Ovules (2–)6–12 per locule; horizontal, or ascending (commonly); biseriate (commonly with two rows in each locule), or superposed; arillate (Euscaphis), or non-arillate; anatropous; bitegmic; crassinucellate. Outer integument contributing to the micropyle. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating; ephemeral. Synergids hooked (with filiform apparatus). Endosperm formation nuclear.
Fruit fleshy, or non-fleshy; in Euscaphis, an aggregate (and sometimes the carpels separating in other genera), or not an aggregate. The fruiting carpel of Euscaphis dehiscent; a follicle. Fruit when syncarpous dehiscent, or a schizocarp (the carpels inflating and opening along their inner sutures, sometimes separating completely, in Staphylea), or indehiscent (in Turpinia). Mericarps when schizocarpic, 2, or 3; comprising follicles (becoming inflated). Fruit when syncarpous a capsule, or a berry, or a drupe (inflated and apically dehiscent in Staphylea, indehiscent and dry to softly fleshy in Turpinia). Seeds copiously endospermic. Endosperm oily. Embryo well differentiated. Cotyledons 2; fleshy, flat or planoconvex. Embryo chlorophyllous (1/1); straight. Micropylenot zigzag.
Seedling.Germination phanerocotylar, or cryptocotylar.
Physiology, biochemistry. Not cyanogenic. Alkaloids present (mostly), or absent. Iridoids not detected. Proanthocyanidins present; cyanidin. Flavonols present; kaempferol and quercetin. Ellagic acid absent (Staphylea). Arbutin absent. Saponins/sapogenins absent. Aluminium accumulation not found. Sugars transported as sucrose, or as sugar alcohols + oligosaccharides + sucrose (in different species of Staphylea).
Geography, cytology. Holarctic, Paleotropical, and Neotropical. Temperate to tropical. Southwest Europe, Eastern Asia, temperate U.S.A., Central America and Northwest South America. X = 13.
Taxonomy.Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Rutiflorae (seemingly misplaced: Gadek et al 1996); Geraniales (? — pending reassignment). Cronquist’s Subclass Rosidae; Sapindales. APG 3 core angiosperms; core eudicot; Superorder Rosanae; malvid; Order Crossosomatales.
Species 60. Genera 5; Euscaphis, Staphylea and Turpinia.