| | Family guide for fruits and seeds |
Synonyms: Marathraceae Dumort.; Philocrenaceae Bong.; Tristichaceae Willis
Common name: Riverweed Family.
Number of genera 48. Number of species 275.
Angiosperm. Magnoliopsida.
Disseminule a dehisced fruit, or an intact or entire fruit, or a seed.
Fruits
Pistil(s) compound; 1; 1-pistillate; with carpels united. Fruit pericarpium; simple, or schizocarp; capsule; coccarium; septicidal capsule, or septifragal capsule (of authors, but not Spjut); capsule not inflated; capsule without operculum; without persistent central column; not within accessory organ(s); more than 1 but less than 10-seeded to many-seeded; 2-seeded (to many); less than 1 cm long; (02.8-)03.5–0.42; (1–)2(–3)-carpellate; with carpels united; with carpels remaining united at maturity; without sterile carpels; not sulcate; in transection terete; apex not beaked; indehiscent, or dehiscent (Farmeria). Dehiscent unit seed(s). Dehiscent at apex; and shedding seeds; without replum. Epicarp durable; glabrous (without hairs); without armature; not smooth; ribbed (6–14 longitudinally); without wing(s); without apical respiratory hole. Endocarp present; not separating from exocarp; thin; not splitting into 1-seeded pyrenes; smooth; without wing; without operculum; without secretory cavities; without mechanism for seedling escape; without grooves; without longitudinal ridges. Funiculus short; short without seed bearing hooks (retinacula); not persisting in fruit after seed shed.
Seeds
Aril absent. Seed larger than minute; less than 1 mm long; 0.25–0.27 mm long; elliptic, or obovate, or circular (sub); in transection compressed; not bowl shaped; not nutlike; without winglike beak; without caudate appendage(s); at maturity without food reserves; without canavanine. Sarcotesta absent. Testa present; without markedly different marginal tissue; without fleshy or leathery layer over hard layer; surface unsmooth; surface with merged raised features; surface reticulate; 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; "dark"; membranous; becoming mucilaginous when wetted; surrounding embryo. Hilum punctate.
Embryo differentiated from food reserve; well developed; 1 per seed; completely filling testa (no food reserve); 1 times the length of food reserve; at one end of seed not extending into a depression or cup; straight; without coleorhiza; without simmondsin; with cotyledons containing oils; without stomata; not green; with 2 or more cotyledons. Cotyledons 2; moderately thick; equal in size, or unequal in size; more or less unequal; not punctate dotted. Hypocotyl-radicle small; not thickened.
Distribution
Cosmopolitan. New World, Old World. North America, Middle America, South America, Europe, Africa, Asia Major, Asia Minor, southeastern Asia, Australia, Oceania.
Notes
Classify, according to Spjut, the indehiscent fruit of Farmeria with 2 equal valves (caducous and deciduous) each with 3 or 5 ribs or 6–14 ribs. Fruit slightly protruding beyond spathilla.
Weed information
No USA noxious weeds.
Listed seeds
No ASOA or ISTA listed seeds.
Accepted genera
Angolaea Wedd. -- Apinagia Tul. -- Blandowia Willd. -- Butumia G. Taylor -- Castelnavia Tul. & Wedd. -- Ceratolacis (Tul.) Wedd. -- Cladopus H. Möller -- Crenias Spreng. -- Dalzellia Wight -- Devillea Tul. & Wedd. -- Dicraeanthus Engl. -- Diplobryum C. Cusset -- Djinga C. Cusset -- Endocaulos C. Cusset -- Farmeria Willis ex Trimen -- Hanseniella C. Cusset -- Hydrobryopsis Engl. -- Hydrobryum Endl. -- Indotristicha P. Royen -- Jenmaniella Engl. -- Ledermanniella Engl. -- Leiothylax Warm. -- Letestuella G. Taylor -- Lonchostephus Tul. -- Lophogyne Tul. -- Macarenia P. Royen -- Macropodiella Engl. -- Maferria C. Cusset -- Malaccotristicha C. Cusset & G. Cusset -- Marathrum Bonpl. -- Monostylis Tul. -- Mourera Aubl. -- Oserya Tul. & Wedd. -- Paleodicraeia C. Cusset -- Podostemum Michx. -- Polypleurum (Tul.) Warm. -- Rhyncholacis Tul. -- Saxicolella Engl. -- Sphaerothylax Bisch. ex O. Krauss -- Stonesia G. Taylor -- Synstylis C. Cusset -- Thelethylax C. Cusset -- Torrenticola Domin -- Tristicha Thouars -- Tulasneantha P. Royen -- Vanroyenella A. Novelo & Philbrick -- Weddellina Tul. -- Wettsteiniola Suess. -- Willisia Warm. -- Winklerella Engl. -- Zehnderia C. Cusset -- Zeylanidium (Tul.) Engl.
References specific to this family
Cronquist page 612. Royen, P. van. 1951. The Podostemaceae of the New World. Part I. Meded. Bot. Mus. Herb. Rijks. Univ. Utrecht 107:1–151, pls. 1–16; Royen, P. van. 1953. The Podostemonaceae of the New World. II. Acta Bot. Neerl. 2:1–21; Royen, P. van. 1954. The Podostemonaceae of the New World. III. Acta Bot. Neerl. 3:215–263; Novelo R., A. & C.T. Philbrick. 1993. Vanroyenella: A new genus of Podostemaceae from Jalisco, Mexico. Syst. Bot. 18:64–67.
General references
Corner, E.J.H. 1976. The seeds of Dicots, esp. vol. 2. Cambridge University Press, New York, Cronquist, A. 1981. An integrated system of classification of flowering plants, 1,262 p. Columbia University Press, New York, Engler, A. and K. Prantl. 1924 and onward. Die Natürlichen Pflanzenfamilimien. W. Engelman, Leipzig, Goldberg, A. 1986 (dicots) and 1989 (monocots). Classification, evolution, and phylogeny of the familes of Dicotyledons. Smithsonian Contr. Bot. 58 for dicots (314 pp.) and 71 for monocots (74 pp.). [Goldberg's illustrations are reproduced from older publications and these should be consulted], 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, Hooker, J.D. 1873 and forward. Icones Plantarum. William & Norgate, London. (plate number cited in text within [ ]), Spjut, R.W. 1994. A systematic treatment of fruit types. Mem. New York Bot. Gard. 70:1–182.
Illustrations
Poor fruit and seed illustrations. Cronquist has no illustration. Disseminule illustration(s): fruit, or seed, or embryo. Fruit illustration(s): Engler & Prantl, Hooker [2356], Novelo R. & Philbrick (1993), Royen (1954). Seed illustration(s): Engler & Prantl, Novelo R. & Philbrick (1993). Embryo illustration(s): Engler & Prantl.
• Fruit. 1 of 8. Mourera fluviatilis Aubl.: fruit. • Seed. 2 of 8. Mourera fluviatilis Aubl.: seeds. • Fruit. 3 of 8. Tulasneantha monadelpha (Bong.) P. Royen: fruit with calyx. • Seed. 4 of 3. Tulasneantha monadelpha (Bong.) P. Royen: seed. • Fruit. 5 of 8. Weddellina squamulosa Tul.: fruit. • Seed. 6 of 8. Weddellina squamulosa Tul.: fruits with seeds. • Seed. 7 of 8. Weddellina squamulosa Tul.: seeds. • Embryo. 8 of 8. Tulasneantha monadelpha (Bong.) P. Royen: poorly differentiated 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’.
