The Families of Flowering Plants
The Families of Flowering Plants | |
~ Triuridaceae
Habit and leaf form. Slender achlorophyllous, leafless herbs (with simple stems). Leaves absent. Plants with roots; saprophytic. Perennial; rhizomatous.
Stem anatomy. Secondary thickening presumably absent.
Reproductive type, pollination. Plants hermaphrodite.
Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’. The ultimate inflorescence unit cymose (sympodial). Inflorescences terminal; lax, racemelike but sympodial, the flowers spiralled, the pedicels long and ascending. Flowers bracteate (the bracts small, trilobed); ebracteolate; small (4–5 mm in diameter); regular (but with very peculiar organization, the androecium inserted internally to the carpels); uniquely organized, with the stamens inserted internally to the gynoecium; more or less 3 merous; probably partially acyclic. Probably the gynoecium acyclic. Floral receptacle centrally depressed, with the carpels surrounding the stamens outside the depression. Perigone tube present (short).
Perianth of ‘tepals’; (4–)6 (the members acuminate to caudate tips); joined; without spots.
Androecium (2–)3(–4). Androecial members free of the perianth; all equal; free of one another; 1 whorled. Androecium exclusively of fertile stamens. Stamens (2–)3(–4) (inserted on the side of the receptacular depression, persistent); very shortly filantherous (the anthers about 0.3 mm long, the filaments about 0.1 mm). Anthers dorsifixed to basifixed (‘sub-basifixed’); dehiscing via longitudinal slits (the locules dehiscing by a single, common slit); introrse; bilocular; seemingly bisporangiate. Endothecium developing fibrous thickenings. The endothecial thickenings probably girdling. Anther epidermis persistent. Anther wall initially with one middle layer. Pollen grains nonaperturate (and intectate); verrucate; 3-celled.
Gynoecium (50–)60–80 carpelled. Carpels increased in number relative to the perianth. Gynoecium apocarpous; eu-apocarpous (the carpels densely papillose); superior. Carpel stylate; with a lateral style (the styles persistent); 1 ovuled. Placentation basal. Ovules anatropous; bitegmic. Outer integument not contributing to the micropyle. Endosperm formation nuclear.
Fruit non-fleshy; an aggregate. The fruiting carpel indehiscent; an achene. Seeds endospermic; ellipsoid with reticulate ornamentation, distally thickened, with a short basal projection. Embryo rudimentary at the time of seed release, or weakly differentiated.
Geography, cytology. Neotropical. Tropical. Mexico.
Taxonomy. Subclass Monocotyledonae. Dahlgren et al. Superorder supposedly Triuridiflorae; supposedly Triuridales (nearest to Triuridaceae, judging from attempting to ‘identify’ this description using INTKEY — assuming that the ‘flower’ is not a contracted inflorescence). APG 3 core angiosperms; Superorder Lilianae; non-commelinid Monocot; Order Pandanales (as a synonym of Triuridaceae).
Species 1. Genera 1; only genus, Lacandonia.
Data encoded from the original, deficient description and fairly unsatisfactory illustrations: Martinez and Ramos (1989), Máquez-Gusmán et al. (1989).
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’.