Potamogeton pusillus

"Red List Category & Criteria: Least Concern ver 3.1 Year Assessed: 2010 Assessor/s: Zhuang, X. Reviewer/s: Homsombath, K., Bounphanmy, S., Juffe Bignoli, D. & Meng, M. Justification: This is a widespread species which faces no major threat. It is listed as Least Concern. Conservation Actions: No conservation measures in place."

Submerged herb, with stems up to 1 m. Rhizome 0 or poorly developed. Stipular sheaths 6-17 mm, tubular, splitting later. Leaves c.20-40 × 1-2 mm, linear, all submerged, firm and translucent; apex obtuse, with 2 lateral longitudinal veins joining the midrib abruptly near the tip at unequal heights. Lacunar system 0 or sometimes a very narrow dense band flanking the midrib. Spikes usually shorter than leaves; flowers 2-4 per whorl with up to 4 whorls per spike. Drupe 2-2.5 mm, obovoid, smooth; beak short and straight.

pusillus: insignificant, small, weak

"Range Description: This species is widespread throughout the whole world except for Australia, New Zealand and islands in the Pacific and Indian Oceans. Countries - Native: Algeria; Argentina; Botswana; Canada (Alberta, British Columbia, Manitoba, Northwest Territories, Saskatchewan, Yukon); Cape Verde; Chile; China (Anhui, Fujian, Gansu, Hainan, Hebei, Heilongjiang, Henan, Hubei, Hunan, Jiangsu, Jilin, Liaoning, Nei Mongol, Ningxia, Qinghai, Shaanxi, Shanxi, Sichuan, Tibet [or Xizang], Xinjiang, Yunnan, Zhejiang); Congo, The Democratic Republic of the; Costa Rica (Costa Rica (main island)); Cyprus; Ecuador (Ecuador (mainland)); Egypt; Eritrea; Ethiopia; Guatemala; Haiti; Honduras (Honduras (mainland)); Hong Kong; India; Iran, Islamic Republic of; Iraq; Kazakhstan; Kenya; Kyrgyzstan; Libyan Arab Jamahiriya; Macao; Malawi; Mauritania; Mexico; Mongolia; Morocco; Mozambique; Myanmar (Myanmar (mainland)); Namibia (Caprivi Strip, Namibia (main part)); Nepal; Nicaragua (Nicaragua (mainland)); Oman; Pakistan; Palestinian Territory, Occupied; Peru; Philippines; Portugal (Azores, Madeira, Portugal (mainland)); Russian Federation (Altay, Buryatiya, Chita, Irkutsk, Krasnoyarsk, Tuva, West Siberia, Yakutiya); Rwanda; Saudi Arabia; Somalia; Spain (Baleares, Canary Is., Spain (mainland)); Sudan; Swaziland; Taiwan, Province of China; Tajikistan; Tanzania, United Republic of; Turkey; Turkmenistan; Uganda; United States; Uruguay; Uzbekistan; Yemen; Zambia; Zimbabwe"

Oases.

Africa, Europe, Asia, North and South America.

Potamogeton pusillus var. longepedunculatus Hicken:
Argentina (South America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Potamogeton uruguayensis Benn. & Graebn.:
Argentina (South America)
Uruguay (South America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Potamogeton berteroanus Phil.:
Argentina (South America)
Brazil (South America)
Chile (South America)
Uruguay (South America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Potamogeton tenuifolius Raf.:
Chile (South America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Potamogeton pusillus L.:
Afghanistan (Asia)
Burma (Asia)
Honduras (Mesoamerica)
India (Asia)
Japan (Asia)
Kyrgyzstan (Asia)
Kazakhstan (Asia)
Mexico (Mesoamerica)
Nicaragua (Mesoamerica)
North Korea (Asia)
Nepal (Asia)
New Guinea (Asia)
Peru (South America)
Philippines (Asia)
Pakistan (Asia)
Russian Federation (Asia)
South Korea (Asia)
Tajikistan (Asia)
Turkmenistan (Asia)
United States (North America)
Uzbekistan (Asia)
Venezuela (South America)
Caribbean (Caribbean)
Guatemala (Mesoamerica)
French Guiana (South America)
Ecuador (South America)
Costa Rica (Mesoamerica)
Canada (North America)
Belize (Mesoamerica)
Argentina (South America)
Brazil (South America)
China (Asia)
Paraguay (South America)
Uruguay (South America)
Bolivia (South America)
Chile (South America)
Colombia (South America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Potamogeton aschersonii A. Benn.:
Argentina (South America)
Brazil (South America)
Chile (South America)
Colombia (South America)
Ecuador (South America)
Peru (South America)
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Widespread in Africa, Europe, temperate Asia and North America. Less common in tropical America and Asia.

This species is widespread throughout the whole world except for Australia, New Zealand and islands in the Pacific and Indian Oceans.

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

United States

Origin: Unknown/Undetermined

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

Distribution: Europe, temperate Asia, Africa and N. America.

Europe, Afriea, temperate Asia, N. Ameriea.

Aquatic, perennating with axillary winter-buds. Stem filiform, c. (0.5-) 1 mm broad, branched. Leaves submerged, sessile, linear, 1-2 mm broad, tip tapering or rounded, 3(-5)-veined, midrib without lacunae. Stipules free, 6-8 mm long, 2 mm broad, ovate, acute, entire, membranous, tubular towards the base. Peduncles 1.2-3 cm long; spikes 5 mm long, few flowered, with 2-4, distant whorls. Perianth segments 1-1.5 mm long, 1-2 mm broad, broadly obtuse. Fruitlets c. 2 mm long, 1-1.5 mm broad, obovoid.

2100-3000 m

Rhizomes absent. Cauline stems terete to slightly compressed, without spots, 18--150 cm; glands present on at least some nodes, green, gold, brown, or rarely white, to 0.5 mm diam. Turions common, soft, lateral or terminal, 0.9--3.2 cm ´ 0.3--1.8 mm, soft; leaves ± 2-ranked; outer leaves 1--3 per side, base not corrugate, apex subulate to obtuse; inner leaves rolled into hardened fusiform structure. Leaves submersed, ± spirally arranged, sessile, delicate to coarse; stipules persistent, inconspicuous, connate or convolute, free from base of blade, brown to green or white, not ligulate, 0.31--0.92 cm, rarely appearing fibrous, not shredding at tip, apex obtuse; blade pale green to olive-green, rarely somewhat reddish, linear, not arcuate, 0.9--6.5 cm ´ 0.2--2.5 mm, base slightly tapering, without basal lobes, not clasping, margins entire, not crispate, apex not hoodlike, subulate to obtuse, lacunae absent or present, in 0--5 rows each side of midrib; veins 1--3(--5). Inflorescences unbranched, submersed or emersed; peduncles not dimorphic, axillary or terminal, erect, rarely recurved, filiform to slightly clavate, 0.5--6.2(--6.6) cm; spikes not dimorphic, capitate to cylindric, 1.5--10.1 mm. Fruits sessile, green to brown, ovoid to obovoid, turgid to concave, not abaxially or laterally keeled, 1.5--2.2 ´ 1.2--1.6 mm; beak erect, 0.1--0.6; sides without basal tubercles; embryo with less than 1 full spiral.

"Habitat and Ecology: It occurs in standing or slow-flowing water in a wide range of habitats, including sheltered lakes and reservoirs, ponds, rivers, streams, canals and ditches. Systems: Freshwater List of Habitats: 5, 5.1, 5.4, 5.7, 15, 15.2, 15.8, 15.9"

Habitat and Ecology

Systems

• Freshwater

Depth range based on 2 specimens in 1 taxon.

Environmental ranges
  Depth range (m): 2 - 2
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

Fl. Per.: June July.

The following is a representative barcode sequence, the centroid of all available sequences for this species.

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 14
Specimens with Barcodes: 24
Species With Barcodes: 1

"Red List Category & Criteria: Least Concern ver 3.1 Year Assessed: 2010 Assessor/s: Zhuang, X. Reviewer/s: Homsombath, K., Bounphanmy, S., Juffe Bignoli, D. & Meng, M. Justification: This is a widespread species which faces no major threat. It is listed as Least Concern. Conservation Actions: No conservation measures in place."

Year Assessed

Assessor/s

Reviewer/s

Contributor/s

Justification

Canada

Rounded National Status Rank: N5 - Secure

United States

Rounded National Status Rank: NNR - Unranked

Rounded Global Status Rank: G5 - Secure

"Population: No population information on this species. However, it is a common species which colonizes a wide variety of freshwater habitats. Population Trend: Unknown"

Population

Population Trend

Major Threats

Conservation Actions