The Families of Flowering Plants
The Families of Flowering Plants | |
Including Ophiraceae Reichb., Ophiriaceae Arn.
Habit and leaf form. Ericoid shrubs. Xerophytic. Leaves opposite (decussate); rolled; leathery; simple. Lamina entire; linear, or lanceolate. Leaves exstipulate (but the opposite bases connected on either side by transverse ridges). Lamina margins strongly revolute.
Leaf anatomy. Stomata present; anomocytic.
Lamina dorsiventral.
Stem anatomy. Cork cambium present; initially superficial. Nodes tri-lacunar. Secondary thickening developing from a conventional cambial ring. Xylem with tracheids; with vessels. Vessel end-walls oblique; scalariform. Wood parenchyma scanty, diffuse.
Root anatomy. Lateral roots without a conspicuous endodermis.
Reproductive type, pollination. Plants hermaphrodite.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in cymes. The fruiting inflorescences conelike. The terminal inflorescence unit cymose. Inflorescences axillary; small, axillary, often villous 3-flowered dichasia, or many-flowered compound dichasia. Flowers bracteate; minute (sessile); regular; cyclic. Free hypanthium absent.
Perianth sepaline (apetalous according to Cronquist 1981); 4 (cf. Cronquist, but interpreted by Fagerlind (1947) as K2 bracteiform plus 2 vestigial, C 2+2 diagonally disposed and valvate); 1 whorled, or 4 whorled (depending on interpretation). Calyx 4 (by either interpretation, as applied to the calyx of Cronquist or the corolla of Fagerlind); 1 whorled (Cronquist), or 2 whorled (under Fagerlind’s interpretation); polysepalous (small); valvate.
Androecium 8. Androecial members free of the perianth and adnate (the antesepalous members slightly adnate to the base of the sepals); markedly unequal (the antesepalous members somewhat longer); free of one another; 2 whorled. Androecium exclusively of fertile stamens. Stamens 8; diplostemonous; alternisepalous (if the ostensible calyx is actually corolla, cf. Fagerlind), or oppositisepalous; filantherous (liguliform, laterally compressed). Anthers adnate (to the distal part of the filament); becoming inverted during development, their morphological bases ostensibly apical in the mature stamens; dehiscing via longitudinal slits; ostensibly extrorse (as a result of ontogenetic inversion). Pollen shed as single grains. Pollen grains aperturate; 3 aperturate; colporate.
Gynoecium 2 carpelled. Carpels isomerous with the perianth. The pistil 1 celled, or 2 celled. Gynoecium syncarpous; eu-syncarpous; inferior. Ovary 2 locular (at least initially, but with an ephemeral partition, and subsequently becoming unilocular). Epigynous disk present (annular, hairy). Gynoecium stylate. Styles 1; apical. Stigmas 1; 1 lobed, or 2 lobed. Placentation apical. Ovules 1 per locule; pendulous; anatropous; unitegmic; tenuinucellate. Endothelium differentiated. Embryo-sac development Polygonum-type. Endosperm formation cellular. Endosperm haustoria present; chalazal and micropylar.
Fruit non-fleshy; dehiscent; achene-like, or a drupe. Gynoecia of adjoining flowers combining to form a multiple fruit (the compact cluster representing each inflorescence resembling a cupressaceous cone). The multiple fruits more or less coalescing. Dispersal unit the inflorescence. Fruit (the true fruit) 1 seeded. Seeds endospermic. Endosperm oily. Cotyledons 2. Embryo straight (long, cylindrical).
Physiology, biochemistry. Iridoids not detected.
Geography, cytology. Cape. Temperate to sub-tropical. South Africa.
Taxonomy. Subclass Dicotyledonae; Tenuinucelli (?). Dahlgren’s Superorder Rosiflorae; Cunoniales (?). Cronquist’s Subclass Dilleniidae; Ericales. APG (1998) Eudicot; core Eudicot; Asterid; unassigned to Euasterid I or Euasterid II; Cornales. Species 5. Genera 2; only genera, Grubbia, Strobilocarpus.
Not yet seen: Fagerlind (1947). Sv. Bot. Tidskr. 41, 315–320.
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: 10th April 2008. http://delta-intkey.com’.