OregonFlora: Elatine brachysperma vs. Elatine minima

	Elatine brachysperma	Elatine minima
	short-seed waterwort
Habit	Plants 3–10 cm.
Stems	green; average internode length 6–15 mm.
Leaves	blades obovate or obovate-elliptic, 3–8 mm; petioles average length 0.5–1 mm.
Inflorescences	peduncles straight; ~0.1 mm.
Flowers	sepals 3; petals 3; stamens 3; as long as petals or slightly shorter; carpels 2–4.
Fruits	globose or pressed globose, 2- to 4-locular.
Seeds	10–45, slightly curved to nearly straight, 0.4–0.5 mm; surface pits < 16 per row; length 0.5–nearly 1 × their width.

	Elatine brachysperma	Elatine minima
Distribution	[WildflowerSearch map] [BONAP county map]	[WildflowerSearch map] [BONAP county map]
Discussion	Mudflats near lakes and reservoirs. Flowering Jun–Jul. 1200–1700 m. BR, Owy, ECas. CA, NV, WA; throughout much of western, southern, and central US, Mexico; Argentina. Native. Elatine brachysperma can be distinguished from other Elatine species growing in Oregon by the number of its seed surface pits, which is fewer than 16 per row. In Oregon, this species is critically imperiled, but it is secure in neighboring states (heritage rank: “G5, S1” [Oregon Biodiversity Information Center, 2016]), e.g., in California.
Source	Flora of Oregon, volume 2, page 613 Hamid Razifard, Gordon Tucker, Donald Les
Sibling taxa	E. californica, E. chilensis, E. rubella	E. brachysperma, E. californica, E. chilensis, E. rubella
Web links	Local floras: BC, CA, OR Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local Web sites: Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Elatine minima

short-seed waterwort

Habit

Plants 3–10 cm.

Stems

green; average internode length 6–15 mm.

Leaves

blades obovate or obovate-elliptic, 3–8 mm;

petioles average length 0.5–1 mm.

Inflorescences

peduncles straight; ~0.1 mm.

Flowers

sepals 3;

petals 3;

stamens 3; as long as petals or slightly shorter;

carpels 2–4.

Fruits

globose or pressed globose, 2- to 4-locular.

Seeds

10–45, slightly curved to nearly straight, 0.4–0.5 mm;

surface pits < 16 per row; length 0.5–nearly 1 × their width.

Elatine minima

Distribution

[WildflowerSearch map]

[BONAP county map]

[WildflowerSearch map]

[BONAP county map]

Discussion

Mudflats near lakes and reservoirs. Flowering Jun–Jul. 1200–1700 m. BR, Owy, ECas. CA, NV, WA; throughout much of western, southern, and central US, Mexico; Argentina. Native.

Elatine brachysperma can be distinguished from other Elatine species growing in Oregon by the number of its seed surface pits, which is fewer than 16 per row. In Oregon, this species is critically imperiled, but it is secure in neighboring states (heritage rank: “G5, S1” [Oregon Biodiversity Information Center, 2016]), e.g., in California.

Source

Flora of Oregon, volume 2, page 613
Hamid Razifard, Gordon Tucker, Donald Les

Sibling taxa

E. californica, E. chilensis, E. rubella

E. brachysperma, E. californica, E. chilensis, E. rubella

Web links