The families of flowering plants
Including Bontiaceae Horan., Spielmannieae (Spielmanniaceae) J.G. Agardh
Habit and leaf form. Small trees, or shrubs; resinous, or not resinous. Normal plants (mosty), or switch-plants (the leaves much reduced in Pholidia scoparia). Mesophytic, or xerophytic. Leaves deciduous; minute to small (often), or medium-sized; alternate, or opposite to whorled (rarely); usually spiral; often more or less leathery; petiolate to sessile; non-sheathing; gland-dotted (often), or not gland-dotted (Oftia); simple; epulvinate. Lamina entire. Leaves exstipulate. Lamina margins entire, or crenate, or serrate, or dentate. Leaf development not graminaceous.
Leaf anatomy. The leaf lamina bifacial (nearly always), or dorsiventral (Oftia). Stomata on both surfaces (usually), or mainly confined to one surface (abaxial only in Oftia); anisocytic (usually), or anomocytic (in Eremophila p.p. and Oftia). Hairs present; eglandular and glandular (the former either uniseriate or multicellular and branched; the latter occurring universally, with long to short, several-celled stalk and vertically partitioned head). Lamina with secretory cavities (usually), or without secretory cavities (Oftia). Secretory cavities containing oil, or containing resin; schizogenous (epithelium lined). The mesophyll containing crystals. The crystals druses, or druses and solitary-prismatic. Minor leaf veins without phloem transfer cells (Myoporum).
Axial (stem, wood) anatomy. Young stems cylindrical. Secretory cavities in primary cortex or pith present (usually, epithelium-lined), or absent (Oftia); with resin, or with oil. Cork cambium present; initially superficial. Nodes unilacunar. Primary vascular tissues of Myoporum in a cylinder, without separate bundles; collateral (usually), or bicollateral (Oftia). Internal phloem present (developing at a late stage as small strands, only in Oftia), or absent (usually). Secondary thickening developing from a conventional cambial ring. Primary medullary rays narrow.
The wood diffuse porous. The vessels small; solitary (rarely), or radially paired, or in radial multiples, or clustered, or in tangential arcs. The vessel end-walls simple. The vessels without vestured pits; without spiral thickening. The axial xylem with fibre tracheids (Bontia), or without fibre tracheids; with libriform fibres (usually), or without libriform fibres; without septate fibres. The fibres without spiral thickening. The parenchyma paratracheal (varying from a few cells to complete sheaths around the vessels, rarely confluent or in narrow terminal bands); wood storied, or partially storied (VP, VPI). Tyloses present, or absent.
Reproductive type, pollination. Unisexual flowers absent. Plants hermaphrodite.
Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in inflorescences; when aggregated, in cymes. The ultimate inflorescence units cymose. Inflorescences axillary. Flowers ebracteate; small, or medium-sized; regular to very irregular; when irregular, more or less zygomorphic. The floral irregularity involving the androecium, or involving the perianth and involving the androecium (not the calyx). Flowers 5 merous; cyclic; tetracyclic. Floral receptacle with neither androphore nor gynophore. Free hypanthium absent.
Perianth with distinct calyx and corolla; (9–)10; 2 whorled; isomerous (usually), or anisomerous. Calyx (4–)5; 1 whorled; more or less polysepalous (commonly), or gamosepalous; when gamosepalous, blunt-lobed, or toothed; unequal but not bilabiate (sometimes), or regular; persistent (scarious); accrescent, or non-accrescent; basally imbricate, or open in bud; with the median member posterior. Corolla more or less disguisedly 5; 1 whorled; gamopetalous; imbricate; bilabiate (often, more or less), or regular.
Androecium (3–)4, or 5. Androecial members adnate (to the corolla tube); all equal, or markedly unequal (mostly); free of one another; 1 whorled. Androecium exclusively of fertile stamens (the upper, posterior member lacking), or including staminodes. Staminodes when present, 1; in the same series as the fertile stamens; representing the posterior median member. Fertile stamens representing the posterior-lateral pair and the anterior-lateral pair. Stamens (3–)4(–5); usually didynamous; reduced in number relative to the adjacent perianth (nearly always), or isomerous with the perianth (rarely); oppositisepalous; alternating with the corolla members. Anthers connivent, or separate from one another; versatile; dehiscing via longitudinal slits, or dehiscing transversely; introrse; unilocular to bilocular (the cells confluent above). Tapetum glandular. Pollen grains aperturate; 2–4 aperturate; colporate (sometimes with two pores per furrow), or rugate; 2-celled.
Gynoecium 2 carpelled. Carpels reduced in number relative to the perianth. The pistil 2 celled, or 3–8 celled. Gynoecium syncarpous; synstylovarious to eu-syncarpous; superior. Ovary 2 locular (but sometimes with secondary segmentation of the locules). Locules secondarily divided by false septa, or without false septa. Gynoecium median; stylate. Styles 1; from a depression at the top of the ovary; apical. Stigmas 1; 1–2 lobed; dry type; papillate; Group II type. Placentation axile, or apical. Ovules (1–)2 per locule (from near the summit), or 4–8 per locule (superposed in pairs), or 1 per locule (per locellus); pendulous; non-arillate; anatropous; unitegmic; tenuinucellate. Endothelium differentiated. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating; persistent. Synergids pear-shaped. Endosperm formation cellular. Endosperm haustoria present; chalazal and micropylar. Embryogeny onagrad.
Fruit fleshy to non-fleshy; indehiscent, or a schizocarp. Mericarps when schizocarpic, 2–10 (? one-seeded); comprising drupelets. Fruit when non-schizocarpic, a drupe. The drupes with separable pyrenes (these one-seeded). Seeds scantily endospermic, or non-endospermic. Cotyledons 2; semi-cylindric. Embryo straight.
Seedling. Germination phanerocotylar.
Physiology, phytochemistry. Cyanogenic, or not cyanogenic. Cynogenic constituents phenylalanine-derived. Alkaloids present, or absent. Verbascosides detected (Eremophila). Iridoids detected; Route II type (+decarb.). Saponins/sapogenins present (rarely), or absent. Proanthocyanidins absent. Flavonols absent. Ellagic acid absent (3 species, 2 genera). Aluminium accumulation not found.
Special distinguishing feature. Lamina tip not abaxially pouched (i.e., not as in Saccifoliaceae).
Geography, cytology. Temperate to tropical. Mainly Australasia and the South Pacific islands, a few in South Africa, Mauritius, Eastern Asia, Hawaii, West Indies. X = 27. Supposed basic chromosome number of family: 27.
Taxonomy. Subclass Dicotyledonae; Tenuinucelli. Dahlgrens Superorder Lamiiflorae; Scrophulariales. Cronquists Subclass Asteridae; Scrophulariales. APG 3 core angiosperms; core eudicot; Superorder Asteranae; lamiid; Order Lamiales (as a synonym of Scrophulariaceae).
Species 90. Genera 4–7; Bontia, Eremophila, Myoporum, Oftia(?), Pholidia, Ranopisoa, Spielmannia (or Scrophulariaceae?).
General remarks. Weakly separable from Scrophulariaceae sensu stricto in terms of these compiled descriptions only via the drupaceous fruits, but supposedly differing also in basic chromosome number.
Illustrations. • Le Maout and Decaisne: Myoporum, Stenochilus. • Myoporum parvifolium: Bot. Mag. 14 (1814). • Myoporum viscosum: Hutchinson. • Eremophila glabra: Bot. Reg. 572, 1821.
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or 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 or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, genera included in each family, and classifications (Dahlgren; Dahlgren, Clifford, and Yeo; Cronquist; APG). See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 24th October 2017. delta-intkey.com/angio’.