Acoraceae

Taxonomy

Family name: Acoraceae Martinov

Synonym(s): none

Common name(s): sweet flag family

*Number of genera & species: 1/2

List of genera (GRIN-Global)

Disseminule

fruit

Description

Fruit a berryberry:
an indehiscent, fleshy fruit with one or a few to many seeds. The flesh may be homogenous throughout. Or, if the outer part is hard, firm, or leathery, referred to as an hesperidium. Septa are present in some, and the seeds may be arillate or with a fleshy testa.
, 4–6 mm long, cylindricalcylindrical:
3D shape—a cylinder, with parallel sides and a circular cross-section; tubular or rod-shaped
to trigonoustrigonous:
3D shape—having three faces that meet at distinct angles; triangular in outline
, with 1–5(–9) seeds, enclosed by tepalstepal:
a member of the perianth, when it cannot be differentiated into a calyx and corolla
. Pericarp white, leatheryleathery:
texture—moderately thick, tough, and very pliable
, glabrousglabrous:
without hairs
, smooth. Mesocarp fleshy.

Seeds oblongoblong:
2D shape—much longer than broad with nearly parallel sides, corners are rounded
to ellipsoidellipsoid:
3D shape—elliptic
, triangulartriangular:
2D shape—three relatively straight sides with distinct corners; more angular than teardrop-shaped
in transection, 1.5–4 mm long. Seed coat light brown without mottling or spotting, smooth and bristlybristly:
having bristles or stiff hair or hair-like structures
(A. gramineus) or with small pits or depressions (A. calamus).

Embryo conical (A. gramineus) or linearlinear:
(shape) long, narrow, and uniform in width; (of embryo) embryo is straight and much longer than wide
(A. calamus), straight, green.

Endosperm copious; perisperm present.

Habitat and crop association

Weedy in wetlands or along streams with aggressive spreading by rhizome.

Aquarium & Pond Plants of the World tool includes a description and images of Acorus.

Identification features

Fruit
Type	berryberry: an indehiscent, fleshy fruit with one or a few to many seeds. The flesh may be homogenous throughout. Or, if the outer part is hard, firm, or leathery, referred to as an hesperidium. Septa are present in some, and the seeds may be arillate or with a fleshy testa.
Size range	4–6 mm long
Shape(s)	oblongoblong: 2D shape—much longer than broad with nearly parallel sides, corners are rounded , ovoidovoid: 3D shape—ovate , cuneiformcuneiform: wedge-shaped , trigonoustrigonous: 3D shape—having three faces that meet at distinct angles; triangular in outline
Texture	epicarp–leathery; mesocarp–fleshy
Surface relief	smooth
Color(s)	white or brown
Unique features	Small fleshy berriesberry: an indehiscent, fleshy fruit with one or a few to many seeds. The flesh may be homogenous throughout. Or, if the outer part is hard, firm, or leathery, referred to as an hesperidium. Septa are present in some, and the seeds may be arillate or with a fleshy testa. with persistent tepalstepal: a member of the perianth, when it cannot be differentiated into a calyx and corolla at maturity.
Seed
Size range	1.5–4 mm long
Shape(s)	oblongoblong: 2D shape—much longer than broad with nearly parallel sides, corners are rounded , ellipsoidellipsoid: 3D shape—elliptic , ovoidovoid: 3D shape—ovate
Surface relief	smooth, pittedpitted: surface relief—surface with small depressions in which the areas between the hollows do not take on the appearance of a true reticular net , punctatepunctate: surface relief—dotted with pits or with translucent, sunken glands or with colored dots, similar to pitted
Color(s)	brown
Unique features	Seeds glabrousglabrous: without hairs in A. calamus and bristlybristly: having bristles or stiff hair or hair-like structures in A. gramineus.
Other
Embryo	conicalconical: 3D shape—cone-shaped, with the point of attachment at the broad end or linearlinear: (shape) long, narrow, and uniform in width; (of embryo) embryo is straight and much longer than wide , straight, green, partially fills seed coat
Nutritive tissue	copious perispermperisperm: seed nutritive tissue comparable to the endosperm, but derived from the nucellus (maternal tissue) and endosperm

Distribution

Temperate Northern Hemisphere (North America, Europe, Northern and Central Asia) and tropical Indo-Malaysia.

Distribution map courtesy of Angiosperm Phylogeny Website.

References

Baskin and Baskin 2021Baskin and Baskin 2021:
Baskin C and Baskin J. 2021. Relationship of the lateral embryo (in grasses) to other monocot embryos: A status up-grade. Seed Science Research 31 (3): 199-210. doi:10.1017/S0960258521000209; Bogner 2011Bogner 2011:
Bogner J. 2011. Acoraceae. Flora Malesiana 20: 1-13.; Dahlgren et al. 1985Dahlgren et al. 1985:
Dahlgren RMT, Clifford HT, and Yeo PF. 1985. The families of the monocotyledons: structure, evolution, and taxonomy. Springer-Verlag, Berlin. 520 pp.; Flora of Australia 2021+Flora of Australia 2021+:
Flora of Australia. Australian Biological Resources Study, Canberra. Accessed January 2021–March 2024. URL: http://www.ausflora.org.au; Flora of North America Editorial Committee 1993+Flora of North America Editorial Committee 1993+:
Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico [Online]. 22+ vols. Flora of North America Association, New York and Oxford. Accessed January-March 2024. URL: http://beta.floranorthamerica.org.; Kirkbride et al. 2006Kirkbride et al. 2006:
Kirkbride JH, Jr, Gunn CR, and Dallwitz MJ. 2006. Family guide for fruits and seeds, vers. 1.0. Accessed September 2020-January 2022. URL: https://nt.ars-grin.gov/seedsfruits/keys/frsdfam/index.cfm .; Kubitzki et al. 1990+Kubitzki et al. 1990+:
Kubitzki K et al., eds. 1990+. The families and genera of vascular plants. 7+ vols. Berlin etc.; Le and Xu 2017Le and Xu 2017:
Le C and Xu Z. 2017. Identication and control of common weeds: Volume 3. Springer Nature, Singapore. 944 pp.; Takhtajan 2009Takhtajan 2009:
Takhtajan A. 2009. Flowering plants: Second edition. Springer Nature, Switzerland. 871 pp.; Zhengyi et al. 2004+Zhengyi et al. 2004+:
Zhengyi W, Raven PH, and Deyuan H. 2004+. Flora of China [online]. 25 vols. Science Press, Beijing China & Missouri Botanical Garden, St. Louis USA. Accessed January–March 2024. http://flora.huh.harvard.edu/china/

*The number of genera and species is based on Christenhusz and Byng 2016Christenhusz and Byng 2016:
Christenhusz MJM and Byng JW. 2016. The number of known plant species in the world and its annual increase. Phytotaxa 261 (3): 201-217. https://doi.org/10.11646/phytotaxa.261.3.1, which may differ from the number of genera in GRIN-Global.