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Synonyms: Thoaceae J. Agardh, nom. inval.
Common name: Gnetum Family.
Number of genera 1. Number of species 28.
Gymnosperm.
Disseminule a cone, or a seed.
Cones
Cone fleshy; an arcesthida when fleshy (mimics a drupe with pink fleshy or corky outer layer (from perianth) & seed with bony testa. Spjut families: Gnetaceae & Cupressaceae (Juniperus).).
Seeds
Aril absent. Seed larger than minute; oblong, or 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 absent. Testa present; with fleshy or leathery layer over hard layer (with thin layer below); tight; shiny; surface unsmooth; surface with merged raised features; surface longitudinally striate; 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; brown (all shades) (assumed); bony (best?); not becoming mucilaginous when wetted; surrounding food reserve. Endosperm copious; without fatty acid containing cyclopropene; without apical lobes; without chlorophyll; without isodiametric faceted surface; without odor.
Embryo differentiated from food reserve; well developed; 1 per seed (only matures, but several when immature); partially filling testa (with food reserve); 1 times the length of food reserve; at one end of seed not extending into a depression or cup; axile and centric; linear (nearly); straight; parallel to seed length; with cotyledons gradually connected to hypocotyl-radicle; without coleorhiza; without simmondsin; without stomata; not green; with 2 or more cotyledons. Cotyledons 2; well developed; 0.75 times length of embryo; somewhat to significantly wider than hypocotyl-radicle; 1.2 times wider than hypocotyl-radicle; not concealing hypocotyl-radicle; not foliaceous; thin; flat; smooth; with apices entire; with margins separate; basally entire; equal in size; not punctate dotted. Hypocotyl-radicle moderately developed; straight; not thickened.
Distribution
Pantropical. New World, Old World. South America, Africa, Asia Minor, southeastern Asia, Australia.
Weed information
No USA noxious weeds.
Listed seeds
No ASOA or ISTA listed seeds.
Accepted genera
Gnetum L.
References specific to this family
Cronquist page 0 (not present).
General references
Gunn, C.R., J.H. Wiersema, C.A. Ritchie, and J.H. Kirkbride, Jr. 1992 and amendments. Families and genera of Spermatophytes recognized by the Agricultural Research Service. Techn. Bull. U.S.D.A. 1796:1–500, Kubitzki, K. 1990. Gnetatae with the single living order Gnetales. In: Kubitzki, K., ed., The families and genera of vascular plants, vol. 1, pp. 378–391. Springer-Verlag, Berlin, Mabberley, D.J. 1987. The plant-book, 706 p. Cambridge University Press, Cambridge, Martin, A.C. 1946. The comparative internal morphology of seeds. Amer. Midl. Naturalist 36:513–660, Spjut, R.W. 1994. A systematic treatment of fruit types. Mem. New York Bot. Gard. 70:1–182.
Illustrations
Acceptable arcesthida and seed illustrations. Disseminule illustration(s): "cone", or seed, or embryo. Illustrated "cone": arcesthida. "Cone" illustration(s): Kubitzki in Kramer & Green, Roosmalen, LeMaout & Decaisne. Seed illustration(s): Karen. Embryo illustration(s): Karen, LeMaout & Decaisne, Martin. Karen's plate number and taxon (taxa): 413: Gnetum scandens Roxb. (A-B).
• Seed. 1 of 3. Gnetum scandens Roxb.: seed. • Embryo. 2 of 3. Gnetum scandens Roxb.: embryos. • Embryo. 3 of 3. Gnetum scandens Roxb.: embryo.
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’.
