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Common name: Pentastemona Family.
Number of genera 1. Number of species 2 (Pentastemona egregria (Schott) Steenis & P. sumatrana Steenis).
Angiosperm. Liliopsida.
Disseminule an intact or entire fruit.
Fruits
Pistil(s) compound; 1; 1-pistillate; with carpels united. Fruit pericarpium; simple; berry (-like); berry without central placental mass; without persistent central column; not within accessory organ(s); many-seeded; many; 3-carpellate; with carpels united; with carpels remaining united at maturity; with carpels not radiating at maturity; with carpels remaining connected at style; without sterile carpels; not sulcate; in transection terete; apex not beaked; wall membranaceous; indehiscent. Epicarp durable; glabrous (without hairs); without armature; with wing(s), or without wing(s); 12-winged; with wing(s) lateral; without apical respiratory hole. Funiculus short; short without seed bearing hooks (retinacula); not persisting in fruit after seed shed.
Seeds
Aril present; a true aril, or an arillike structure (not sure which one); well developed; fleshy; of funicular origin; basal and marginal; does not aid in seed explusion from fruit; fleshy; winged-blatter; lobed. Arillike structure falling with seed an arillode (vesicular). Seed larger than minute; less than 1 mm long, or 1 to less than 5 mm long; 0.9–1.5 mm long; circular; in transection terete; not bowl shaped; not nutlike; without winglike beak; without caudate appendage(s); at maturity with food reserves; with endosperm; without canavanine. Sarcotesta present (transparent); fleshy. Testa present; without markedly different marginal tissue; with fleshy or leathery layer over hard layer; shiny; surface unsmooth; surface with merged raised features; surface 10–13 faint ridged; without crease or line separating cotyledons from hypocotyl-radicle; without notch along margin where cotyledons from hypocotyl-radicle tip approach each other; without glands; without bristles; glabrous; without wings; without collar; without operculum; colored; monochrome; not becoming mucilaginous when wetted; surrounding food reserve. Raphe inconspicuous. Endosperm copious; with starch; with lipids; without fatty acid containing cyclopropene; without apical lobes; without chlorophyll; without isodiametric faceted surface; without odor.
Embryo differentiated from food reserve; rudimentary; 1 per seed; partially filling testa (with food reserve); 0.2 times the length of food reserve; at one end of seed not extending into a depression or cup; miniature; dwarf, or micro; straight; parallel to seed length; surrounding endosperm; with cotyledons gradually connected to hypocotyl-radicle; without coleoptile; without coleorhiza; without simmondsin; without stomata; not green; with 1 cotyledon. Cotyledons one and not modified into scutellum; not circinately coiled.
Distribution
Old World. Southeastern Asia.
Notes
Steenis (1982): Seed "with rather thick transparent sarcotesta though which the ribbed endocarp shimmers through". [He obviously meant testa not endocarp.] Steenis futher noted that the fruit could have entire wings in P. sumatrana, or have "short often antler-like branched, hair-like emergences" in P. egregia. [The latter character is not scored, the former character is scored.].
Weed information
No USA noxious weeds.
Listed seeds
No ASOA or ISTA listed seeds.
Accepted genera
Pentastemona Steenis
References specific to this family
Cronquist page 1224 (Cronquist & Mabberley have in Stemonaceae). Duyfjes, B.E.E. 1992. Formal description of the family Pentastemonaceae with some additional notes on Pentastemonaceae and Stemonaceae. Blumea 36:551–552; Steenis, C.G.G.J. van. 1982. Pentastemona, a new 5-merous genus of monocotyledons from North Sumatra (Stemonaceae). Blumea 28:151–163; Bouman, F. & N. Devente. 1992. A comparison of the structure of ovules and seeds in Stemona (Stemonaceae) and Pentastemona (Pentastemonaceae). Blumea 36:501–514.
Illustrations
Acceptable fruit and seed illustrations. Disseminule illustration(s): fruit, or seed. Fruit illustration(s): Steenis (1982). Seed illustration(s): Steenis (1982).
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or 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, and distributions of character states within any set of taxa. See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘J.H. Kirkbride, Jr., C.R. Gunn, and M.J. Dallwitz. 2000 onwards. Family guide for fruits and seeds: descriptions, illustrations, identification, and information retrieval. Version: 12th April 2021. delta-intkey.com’.