The families of flowering plants
Habit and leaf form. Weak, straggling coastal shrubs (to 150 cm high). Plants succulent. Xerophytic. Leaves small; opposite; flat, or terete (flat above, convex below); fleshy; subsessile to sessile; slightly connate; strong-scented; simple. Lamina entire; linear, or oblong, or obovate. Leaves exstipulate (ostensibly), or stipulate (interpretable as such, in that each leaf bears an ephemeral, glandular pair within its briefly clasping base). Stipules represented by glands; caducous. Vegetative buds not scaly.
Leaf anatomy. The leaf lamina bifacial to centric (adaxially grooved and stem-clasping at the base, sub-cylindrical in the middle, and cylindrical towards the tip). Stomata paracytic. Hairs absent (or scarce). The mesophyll containing crystals. The crystals druses and solitary-prismatic.
Axial (stem, wood) anatomy. Young stems tetragonal. Cork cambium present; initially deep-seated (inside the bundles of pericyclic fibres). Primary vascular tissues comprising a ring of bundles to comprising two or more rings of bundles (with a ring of 3–5 bundles corresponding with the angles of the stem, and a single but smaller bundle on either side); collateral. Internal phloem absent. Cortical bundles present (the two small ones, which are not leaf traces). Secondary thickening absent, or developing from a conventional cambial ring (?). Primary medullary rays wide.
The vessel end-walls horizontal to oblique; simple. The vessels with vestured pits. The axial xylem with fibre tracheids. Included phloem absent. The wood partially storied (VPI).
Reproductive type, pollination. Plants monoecious, or dioecious. Gynoecium of male flowers vestigial, or absent.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in inflorescences; in spikes. The ultimate inflorescence units racemose. Inflorescences axillary; conical, strobiloid spikes with flowers in four ranks. Flowers bracteate (the bracts cochleariform and imbricate in male inflorescences, smaller and partially incorporated in the fleshy female spike); small; those of of male plants somewhat irregular to very irregular; male flowers zygomorphic. The floral irregularity of male flowers involving the perianth. Flowers (male) 4 merous; male flowers cyclic. Free hypanthium absent. Hypogynous disk absent.
Perianth with distinct calyx and corolla (in male flowers), or absent (in female flowers, where the lower bracts are united); of male flowers 2 whorled. Calyx of male flowers 1 whorled; gamosepalous; blunt-lobed; cupuliform, or campanulate; bilabiate. Corolla of male flowers 4; 1 whorled; polypetalous, or gamopetalous (the claws more or less united); regular. Petals clawed.
Androecium of male flowers 4. Androecial members free of the perianth; all equal; free of one another; 1 whorled. Androecium exclusively of fertile stamens. Stamens 4; isomerous with the perianth; oppositisepalous (at least, alternating with the corolla). Anthers dorsifixed; versatile; dehiscing via longitudinal slits; introrse; tetrasporangiate; briefly appendaged. The anther appendages apical (by short extension of the connective). Endothecium developing fibrous thickenings. Anther wall initially with more than one middle layer. Pollen grains aperturate; 3(–4) aperturate; colporate, or rugate (colporoidate or ruporoidate); 2-celled.
Gynoecium of female flowers 2 carpelled (but secondarily partitioned from each carpel midrib). The pistil 4 celled. Gynoecium syncarpous; synstylovarious; superior (but the 810 gynoecia of adjoining flowers coherent, and adherent to the bract bases). Ovary 2 locular (but these sesondarily partitioned). Locules secondarily divided by false septa. Ovary sessile. Gynoecium non-stylate. Stigmas 2 (sessile). Placentation basal. Ovules 1 per locule; funicled; ascending; anatropous.
Fruit fleshy; indehiscent; a drupe. The drupes with separable pyrenes (four). Gynoecia of adjoining flowers combining to form a multiple fruit. The multiple fruits coalescing. Seeds non-endospermic. Embryo well differentiated. Cotyledons 2; fleshy. Embryo straight.
Seedling. Germination phanerocotylar.
Physiology, phytochemistry. C3. C3 physiology recorded directly in Batis. Mustard-oils present. Not cyanogenic. Alkaloids absent (one species). Iridoids not detected. Betalains absent. Proanthocyanidins absent. Ellagic acid absent. Sieve-tube plastids S-type.
Geography, cytology. Paleotropical, Neotropical, and Australian. Tropical. Pacific, West Indies, north coastal South America, central America to Florida, New Guinea, Queensland. N = 9.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgrens Superorder Violiflorae (? - or Caryophylliflorae); Capparales. Cronquists Subclass Dilleniidae; Batales. APG 3 core angiosperms; core eudicot; Superorder Rosanae; malvid; Order Brassicales.
Species 2. Genera 1; only genus, Batis.
Illustrations. • Technical details: Batis. • Batis argillicola: Van Royen, Fl. Malesiana 5 (1955).
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: 12th September 2017. delta-intkey.com/angio’.