Juncaginaceae

Taxonomy

Family name: Juncaginaceae L. Richard

Synonym(s): Lilaeaceae Dumort., nom. cons.; Triglochinaceae Bercht. & J. Presl

Common name(s): arrow-grass family

*Number of genera/species: 3/34

List of genera records in GRIN-Global

Disseminule

fruit

Description

Fruit an acheneachene:
a dry, indehiscent, one-seeded fruit, with seed attached to pericarp at a single point, derived from a single, superior, simple or compound, one-loculed ovary
, single or aggregated into a schizocarpschizocarp:
usually dry fruit splitting between two or more locules to form distinct, indehiscent, usually one seeded segments; fruit derived from a single, superior or inferior, compound ovary; compare to mericarp
, 1.5–8.5 mm long, globoseglobose:
3D shape—more or less spherical
to angularangular:
2D shape—having sides that meet at acute or obtuse angles  
, tereteterete:
approximately circular in cross section; width and thickness approximately equal
, angledangular:
2D shape—having sides that meet at acute or obtuse angles  
, or compressedcompressed:
flattened; in grasses, used to denote compression (not necessarily flattened) either laterally or dorsiventrally
in transection, sometimes beakedbeak:
a usually firm, terminal appendage, sometimes tapered
with persistent stylestyle:
in a flower, the narrow and elongated part of the pistil between the stigma and the ovary; sometimes persisting in fruit
(Tetronicum), with one seed. Pericarppericarp:
fruit wall or fruit coat
brown, dulldull:
reflecting only a low proportion of incident light, with no apparent sheen
, leatheryleathery:
texture—moderately thick, tough, and very pliable
, smooth, ribbedribbed:
surface relief—wide, prominent, linear ridges that are generally rounded and longitudinally situated on the surface
, rarely with apicalapical:
at or pertaining to the end of the seed or fruit distal from its point of attachment (i.e., base)
hooks or hornshorn:
a straight or curved, slenderly conic or conoidal protrusion, resembling an animal horn
.

Triglochin species except for T. scilloides have three sterilesterile:
lacking male and/or female reproductive parts; also, not producing fruit or seed
carpels that alternate with three fertile carpels, which at maturity break up into three one-seeded mericarpsmericarp:
a one-seeded section (carpel) of a schizocarp, as in Apiaceae fruits (compare schizocarp)
(achenesachene:
a dry, indehiscent, one-seeded fruit, with seed attached to pericarp at a single point, derived from a single, superior, simple or compound, one-loculed ovary
) attached at the apexapex:
the point farthest from the point of attachment, or the "tip" of an organ
. Triglochin scilloides achenesachene:
a dry, indehiscent, one-seeded fruit, with seed attached to pericarp at a single point, derived from a single, superior, simple or compound, one-loculed ovary
are flattened to angularangular:
2D shape—having sides that meet at acute or obtuse angles  
and three-winged.

Seeds linearlinear:
(shape) long, narrow, and uniform in width; (of embryo) embryo is straight and much longer than wide
, oblongoblong:
2D shape—much longer than broad with nearly parallel sides, corners are rounded
, or ovoidovoid:
3D shape—ovate
, tereteterete:
approximately circular in cross section; width and thickness approximately equal
in transection. Seed coat brown.

Embryo well developed, linearlinear:
(shape) long, narrow, and uniform in width; (of embryo) embryo is straight and much longer than wide
, straight or bentbent:
(of embryo) embryo is bent at an acute, V-shaped angle with the ends close together and generally thick cotyledons
, completely filling seed coat, with a massive cotyledoncotyledon:
a primary leaf of the embryo
, a laterallateral:
(of embryo) embryo lies along the side of the seed, generally towards one end; of, at, or from the side; in grasses, can refer to the sides adjacent to the dorsal and ventral sides
stem tip, and terminal radicleradicle:
the embryonic root of the embryo
.

Endosperm lacking.

Habitat and crop association

Aquarium & Pond Plants of the World tool includes descriptions and images of Triglochin.

Identification features

Fruit
Type	acheneachene: a dry, indehiscent, one-seeded fruit, with seed attached to pericarp at a single point, derived from a single, superior, simple or compound, one-loculed ovary
Size range	1.5–8.5 mm long
Shape(s)	ellipsoidellipsoid: 3D shape—elliptic , cylindricalcylindrical: 3D shape—a cylinder, with parallel sides and a circular cross-section; tubular or rod-shaped , trigonoustrigonous: 3D shape—having three faces that meet at distinct angles; triangular in outline , globoseglobose: 3D shape—more or less spherical , lanceoloidlanceoloid: 3D shape—lanceolate , oblateoblate: depressed globose , cylindricalcylindrical: 3D shape—a cylinder, with parallel sides and a circular cross-section; tubular or rod-shaped , angularangular: 2D shape—having sides that meet at acute or obtuse angles   , linearlinear: (shape) long, narrow, and uniform in width; (of embryo) embryo is straight and much longer than wide , ovoidovoid: 3D shape—ovate
Texture	leatheryleathery: texture—moderately thick, tough, and very pliable
Surface relief	ribbedribbed: surface relief—wide, prominent, linear ridges that are generally rounded and longitudinally situated on the surface or with hookswith hooks: bristles or spines with curved or backwards pointing tips, or with secondary bristles along their length or hornshorn: a straight or curved, slenderly conic or conoidal protrusion, resembling an animal horn
Color(s)	brown
Unique features	Variously shaped, leatheryleathery: texture—moderately thick, tough, and very pliable , smooth or ribbedribbed: surface relief—wide, prominent, linear ridges that are generally rounded and longitudinally situated on the surface achenesachene: a dry, indehiscent, one-seeded fruit, with seed attached to pericarp at a single point, derived from a single, superior, simple or compound, one-loculed ovary , rarely with apicalapical: at or pertaining to the end of the seed or fruit distal from its point of attachment (i.e., base) hooks or hornshorn: a straight or curved, slenderly conic or conoidal protrusion, resembling an animal horn .
Seed
Shape(s)	linearlinear: (shape) long, narrow, and uniform in width; (of embryo) embryo is straight and much longer than wide , oblongoblong: 2D shape—much longer than broad with nearly parallel sides, corners are rounded , or ovoidovoid: 3D shape—ovate
Color(s)	brown
Other
Embryo	well developed, linearlinear: (shape) long, narrow, and uniform in width; (of embryo) embryo is straight and much longer than wide , straight or bentbent: (of embryo) embryo is bent at an acute, V-shaped angle with the ends close together and generally thick cotyledons , completely filling seed coat, with a massive cotyledoncotyledon: a primary leaf of the embryo , a laterallateral: (of embryo) embryo lies along the side of the seed, generally towards one end; of, at, or from the side; in grasses, can refer to the sides adjacent to the dorsal and ventral sides stem tip, and terminal radicleradicle: the embryonic root of the embryo
Nutritive tissue	endosperm lacking

Distribution

Worldwide.

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; 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; 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.; Stevenson and Loconte 1995Stevenson and Loconte 1995:
Stevenson DW and Loconte H. 1995. A cladistic analysis of monocot families. In: Rudall PJ, Cribb PJ, Cutler DF, and Humphries CJ, eds. Monocotyledons: Systematics and Evolution. Royal Botanic Gardens, Kew.; Tutin et al. 1964–1980Tutin et al. 1964–1980:
Tutin TG, Burges NA, Chater AO, Edmondson JR, Heywood VH, Moore DM, Valentine DH, Walters SM, and Webb DA (eds.) 1964–1980. Flora Europaea. 5 vols. Cambridge University Press, Cambridge UK. 2,524 pp.; Watson and Dallwitz 1992+Watson and Dallwitz 1992+:
Watson L and Dallwitz MJ. 1992+. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 6th Accessed September 2020-September 2022. URL: delta-intkey.com

*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.