The families of flowering plants
The families of flowering plants | |
~ Hernandiaceae
Habit and leaf form. Small trees, or shrubs, or lianas. Self supporting, or climbing. Mesophytic. Leaves alternate; petiolate; non-sheathing; simple. Lamina dissected, or entire; when dissected, palmatifid; palmately veined; cross-venulate. Leaves exstipulate; without a persistent basal meristem.
Leaf anatomy. Stomata anomocytic.
Adaxial hypodermis present. Lamina dorsiventral; without secretory cavities. Cystoliths present. The mesophyll with spherical etherial oil cells.
Stem anatomy. Secretory cavities absent. Nodes unilacunar (with two traces). Primary vascular tissue in a cylinder, without separate bundles. Secondary thickening developing from a conventional cambial ring. Xylem with fibre tracheids. Wood parenchyma paratracheal. Sieve-tube plastids P-type; type I (b).
Reproductive type, pollination. Plants andromonoecious, or polygamomonoecious.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in cymes, in corymbs, and in panicles. The ultimate inflorescence unit cymose. Inflorescences dense thyrses. Flowers cyclic. Free hypanthium absent.
Perianth sepaline; (4–)8 (male flowers), or 2 (bisexual flowers); joined; 1 whorled. Calyx (if the perianth be so interpreted) (4–)8 (male flowers), or 2 (or at least, 2-lobed, in bisexual flowers); gamosepalous; persistent; in bisexual flowers accrescent (and winged); imbricate (in male flowers).
Androecium 3–5, or 6–9 (when staminodes present). Androecial members free of the perianth; free of one another; 1 whorled, or 2 whorled. Androecium exclusively of fertile stamens, or including staminodes (these sometimes present in male as well as in bisexual flowers). Staminodes when present, 3–7. Stamens 3–5. Anthers basifixed; dehiscing by longitudinal valves; latrorse. Pollen grains nonaperturate; 2-celled (in both genera).
Gynoecium 1 carpelled. The pistil 1 celled. Gynoecium monomerous; of one carpel; inferior. Carpel 1 ovuled. Placentation marginal.
Fruit non-fleshy. The fruiting carpel indehiscent (winged via the persistent, accrescent lobes of the perianth). Seeds non-endospermic. Cotyledons 2 (leafy, convolute).
Physiology, biochemistry. Alkaloids present. Aluminium accumulation not found.
Geography, cytology. Sub-tropical to tropical. Pantropical and subtropical.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Magnoliiflorae; Laurales. Cronquist’s Subclass Magnoliidae; Laurales. APG 3 core angiosperms; Superorder Magnolianae; Order unassigned to Order (formerly regarded as a synonym of Hernandiaceae, i.e. Laurales).
Species 22. Genera 2; Gyrocarpus, Sparattanthelium.
Illustrations. • Technical details: Gyrocarpus, Sparattanthelium.
This description is offered for casual browsing only. We strongly advise against extracting comparative information from it. This is much more easily achieved using 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).
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 December 2012. http://delta-intkey.com’.
