The families of flowering plants
Including Hirtellaceae Nak., Hirtellaceae Horan (p.p.).
Habit and leaf form. Trees and shrubs; leptocaul. Leaves alternate; spiral; petiolate; non-sheathing; simple. Lamina entire; pinnately veined; cross-venulate. Leaves stipulate.
General anatomy. Plants with silica bodies, or without silica bodies.
Leaf anatomy. The leaf lamina dorsiventral, or bifacial (the whole mesophyll usually comprising palisade). Epidermis containing silica bodies (often), or without silica bodies. Mucilaginous epidermis present (often), or absent. Stomata paracytic. Adaxial hypodermis often present. Lamina with secretory cavities, or without secretory cavities. The mesophyll with sclerenchymatous idioblasts (sometimes, in the form of fibre-like spicular cells), or without sclerenchymatous idioblasts. Minor leaf veins without phloem transfer cells (Moquilea (= Licanea)).
Axial (stem, wood) anatomy. Cork cambium present; initially superficial. Primary vascular tissues in a cylinder, without separate bundles; collateral. Internal phloem absent. Cortical bundles absent. Medullary bundles absent. Secondary thickening developing from a conventional cambial ring. Primary medullary rays narrow (exclusively or predominantly uniseriate).
The vessel end-walls simple. The axial xylem with tracheids. The parenchyma apotracheal. Included phloem absent.
Reproductive type, pollination. Plants hermaphrodite, or andromonoecious, or gynomonoecious.
Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in inflorescences; when aggregated, in cymes, or in racemes. The ultimate inflorescence units cymose, or racemose. Inflorescences terminal, or axillary; simple or compound racemes, or (e.g. Parinari) cymes. Flowers small; very irregular. The floral irregularity involving the perianth and involving the androecium. Flowers cyclic, or partially acyclic. The androecium acyclic. Free hypanthium present (tubular).
Perianth with distinct calyx and corolla, or sepaline (rarely, the corolla absent); (5–)6–10; 1 whorled (rarely), or 2 whorled; isomerous, or anisomerous. Calyx 5; 1 whorled; gamosepalous; unequal but not bilabiate (sometimes saccate at the base); imbricate; with the median member posterior. Corolla when present, 1–5; 1 whorled; polypetalous (inserted at the mouth of the hypanthium tube); imbricate; more or less unequal but not bilabiate. Petals shortly clawed.
Androecium (2–)8–20(–300). Androecial members branched (from trunk bundles?), or unbranched; free of the perianth (but inserted with the corolla at the mouth of the hypanthium); often markedly unequal (those on the side opposite the larger calyx segments often larger); free of one another, or coherent; when coherent 1 adelphous, or 3–20 adelphous (? connate, or joined into groups). Androecium exclusively of fertile stamens, or including staminodes. Stamens (2–)8–30(–300); isomerous with the perianth to polystemonous. Anthers dorsifixed (below the midline); versatile; dehiscing via longitudinal slits; introrse. Pollen grains aperturate; 3(–4) aperturate; colpate, or colporate.
Gynoecium 1–3 carpelled (two members usually more or less reduced, the developed member then simulating G1 and excentrically situated in the hypanthium). The pistil 1–3 celled. Gynoecium monomerous, or syncarpous; of one carpel (at least ostensibly), or synstylovarious to eu-syncarpous; superior. Carpel stylate; with a gynobasic style; 2 ovuled (but the one locule is occasionally subdivided, to look like two one-ovulate locules). Placentation basal. Ovary 1(–3) locular. Locules secondarily divided by false septa (sometimes), or without false septa. Gynoecium stylate. Styles 1; gynobasic. Stigmas 1 lobed, or 3 lobed. Placentation basal. Ovules 2 per locule (sometimes one per locellus); ascending; collateral, or over the carpel surface (?).
Fruit fleshy. The fruiting carpel indehiscent; drupaceous (with bony endocarp). Fruit 1 seeded. Seeds non-endospermic. Embryo well differentiated. Cotyledons 2 (commonly thickened).
Seedling. Germination cryptocotylar.
Physiology, phytochemistry. Sugars transported as sucrose (in Licania and Parinari). Not cyanogenic. Alkaloids absent. Iridoids not detected. Saponins/sapogenins absent. Proanthocyanidins present; cyanidin, or delphinidin. Flavonols present; kaempferol, quercetin, and myricetin, or quercetin and myricetin, or kaempferol and quercetin. Ellagic acid absent (3 genera).
Geography, cytology. Mostly tropical, sub-tropical. Widespread-tropical. X = 10, 11.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgrens Superorder Rosiflorae; Rosales. Cronquists Subclass Rosidae; Rosales. APG 3 core angiosperms; core eudicot; Superorder Rosanae; fabid; Order Malpighiales.
Species 400. Genera 17; Acioa, Atuna, Bafodeya, Chrysobalanus, Coupeia, Dactyladenia, Exellodendron, Grangeria, Hirtella, Hunga, Kostermanthus, Licania, Magnistipula, Maranthes, Neocarya, Parastemon, Parinari.
Illustrations. • Technical details: Parinarium (Thonner). • Chrysobalanus icaco and Grangeria borbonica: Nat. Pflanzenfam. III (1894), with Stylobasium.
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: 19th October 2016. delta-intkey.com’.