The Families of Flowering Plants
The Families of Flowering Plants | |
~ Pedaliaceae
Habit and leaf form. Aquatic herbs. Perennial; rhizomatous. Hydrophytic; rooted (with creeping rhizome and floating stems). Leaves submerged and floating. Heterophyllous (the lower leaves narrow, oblong, remotely serrate, the floating leaves broad, deltoid-rotundate, crenate). Leaves opposite; simple. Lamina entire. Leaves exstipulate. Lamina margins crenate (floating), or serrate (submerged).
Leaf anatomy. Hydathodes present (in the indentations of the blade margins). Stomata when present, anomocytic.
Stem anatomy. Vessel end-walls simple.
Reproductive type, pollination. Unisexual flowers absent. Plants hermaphrodite.
Inflorescence, floral, fruit and seed morphology. Flowers solitary (chasmogamous floating and cleistogamous submerged); axillary (usually only one developed at each node despite the opposite leaves); very irregular; zygomorphic. The floral irregularity involving the perianth and involving the androecium. Flowers cyclic; tetracyclic. Free hypanthium absent.
Perianth with distinct calyx and corolla; 10; 2 whorled; isomerous. Calyx 5; 1 whorled; polysepalous; persistent; imbricate; with the median member posterior. Corolla 5; 1 whorled; gamopetalous; imbricate; slightly bilabiate (with two upper and three lower lobes, the upper lip exterior).
Androecium 4. Androecial members adnate (to the corolla); free of one another; 1 whorled. Androecium including staminodes. Staminodes 2; in the same series as the fertile stamens; representing the anterior-lateral pair (anticolous). Fertile stamens representing the posterior-lateral pair (latero-posterior). Stamens 2; reduced in number relative to the adjacent perianth; oppositisepalous; alternating with the corolla members; filantherous (the filaments filiform). Anthers borne on a large, peltate connective, included. Pollen grains aperturate; 3 aperturate; colporate (colporoidate, the oroids provided with operculoid membranes).
Gynoecium 2 carpelled. Carpels reduced in number relative to the perianth. The pistil 2 celled. Gynoecium syncarpous; synstylovarious to eu-syncarpous; inferior. Ovary 2 locular. Locules without ‘false septa’. Gynoecium median; stylate. Styles 1; apical. Stigmas unequally 2 lobed. Placentation axile to apical. Ovules 2 per locule (in the posterior locule only, the anterior abortive and empty); pendulous; anatropous; unitegmic; tenuinucellate. Endosperm formation cellular.
Fruit non-fleshy; indehiscent; a nut (conspicuously appendaged). Dispersal unit crowned with five spreading, rigid appendages below the calyx, three elongate, slender and uncinate, the other two short, subulate and spinose. Fruit 1 seeded. Seeds thinly endospermic. Embryo straight.
Geography, cytology. Holarctic. Temperate to tropical. Eastern Asia.
Taxonomy. Subclass Dicotyledonae; Tenuinucelli. Dahlgren’s Superorder Lamiiflorae; Scrophulariales. Cronquist’s Subclass Asteridae; Scrophulariales. APG 3 core angiosperms; core eudicot; Superorder Asteranae; lamiid; Order Lamiales (as a synonym of Pedaliaceae).
Species 2. Genera 1; only genus, Trapella.
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 specified attributes, summaries of attributes within groups of taxa, geographical distribution, genera included in each family, classifications (Dahlgren; Dahlgren, Clifford, and Yeo; Cronquist; APG), and notes on the APG classification.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 25th November 2009. http://delta-intkey.com’.