The Families of Flowering Plants
The Families of Flowering Plants |
|
~ Geraniaceae, rather than Oxalidaceae
Habit and leaf form. Stemless herbs. Perennial (with a thick taproot); with a basal aggregation of leaves. Leaves alternate; spiral; simple. Lamina dissected; pinnatifid. Leaves exstipulate.
Stem anatomy. Sieve-tube plastids S-type.
Reproductive type, pollination. Fertile flowers hermaphrodite. Plants hermaphrodite.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in cymes. The ultimate inflorescence unit cymose. Inflorescences radical, pedunculate or epedunculate 1–9-flowered cymes. Flowers regular; 5 merous; cyclic; polycyclic. Floral receptacle developing a gynophore (the gynoecium attached to a central column). Free hypanthium absent.
Perianth with distinct calyx and corolla; 10; 2 whorled; isomerous. Calyx 5; 1 whorled; polysepalous; regular; persistent; strongly imbricate. Corolla 5; 1 whorled; polypetalous; contorted.
Androecium 15. Androecial members free of the perianth; free of one another; 3 whorled. Androecium exclusively of fertile stamens. Stamens 15; triplostemonous; filantherous (the filaments subulate, persistent). Anthers dorsifixed; dehiscing via longitudinal slits; introrse. Pollen grains aperturate; 3 aperturate; colporate.
Gynoecium 5 carpelled. Carpels isomerous with the perianth. The pistil 5 celled. Gynoecium syncarpous; eu-syncarpous; superior. Ovary 5 locular (and five lobed); stipitate. Gynoecium stylate (the style filiform). Styles 1; apical. Stigmas 1; capitate. Placentation axile. Ovules 20–50 per locule (‘many’); biseriate; non-arillate; anatropous to campylotropous (becoming campylotropous after fertilization, via a bulge from the inner integument on the raphal side — cf. Geraniaceae); bitegmic; crassinucellate. Outer integument contributing to the micropyle. Hypostase present. Endosperm formation ab initio nuclear, or cellular (subsequently, commencing around the embryo).
Fruit non-fleshy; tardily dehiscent; a capsule. Capsules irregularly loculicidal (unlike the specialized structure of typical of Geraniaceae). Seeds scantily endospermic. Embryo well differentiated. Embryo coiled (‘cochlear’). Micropyle zigzag.
Geography, cytology. Neotropical. Andes.
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Rutiflorae; Geraniales (?). Cronquist’s Subclass Rosidae; Geraniales. APG 3 core angiosperms; core eudicot; Superorder Rosanae; malvid; Order Geraniales (as a synonym of Geraniaceae).
Species 8. Genera 1; only genus, Hypseocharis.
Boesewinkel (1988) shows that the embyology and seed structure resemble Geraniaceae rather than Oxalidaceae or Linaceae.
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’.