''Crassula aquatica'' is a
succulent plant
In botany, succulent plants, also known as succulents, are plants with parts that are thickened, fleshy, and engorged, usually to retain water in arid climates or soil conditions. The word ''succulent'' comes from the Latin word ''sucus'', meanin ...
known by the common names water pygmyweed,
common pygmyweed and just pigmyweed.
It is an
annual plant
An annual plant is a plant that completes its life cycle, from germination to the production of seeds, within one growing season, and then dies. Globally, 6% of all plant species and 15% of herbaceous plants (excluding trees and shrubs) are ...
of
salt marsh
A salt marsh, saltmarsh or salting, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open saltwater or brackish water that is regularly flooded by the tides. I ...
es,
vernal pool
Vernal pools, also called vernal ponds or ephemeral pools, are seasonal pools of water that provide habitat for distinctive plants and animals. They are considered to be a distinctive type of wetland usually devoid of fish, and thus allow the saf ...
s, wetlands, and other fresh to brackish water bodies. It is at least partially
aquatic
Aquatic means relating to water; living in or near water or taking place in water; does not include groundwater, as "aquatic" implies an environment where plants and animals live.
Aquatic(s) may also refer to:
* Aquatic animal, either vertebrate ...
, living in areas which are submersed much of the time. It also lives along muddy banks and in tidally-active areas of
estuaries
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environm ...
.
Description
''Crassula aquatica'' is a small plant forming thin mats or small patches on mud and sand, and growing more erect when exposed to open air for longer periods. The flesh of the plant is greenish-yellow to bright red or purplish. The tiny fleshy pointed leaves are only a few millimeters long.
A flower grows on a short stalk from the intersection of each oppositely-arranged pair of leaves. The flower is only about two millimeters long and wide. The fruit is a minute
follicle containing several seeds.
Distribution and habitat
This plant is widespread across North America and Eurasia. It is an
annual plant
An annual plant is a plant that completes its life cycle, from germination to the production of seeds, within one growing season, and then dies. Globally, 6% of all plant species and 15% of herbaceous plants (excluding trees and shrubs) are ...
of
salt marsh
A salt marsh, saltmarsh or salting, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open saltwater or brackish water that is regularly flooded by the tides. I ...
es,
vernal pool
Vernal pools, also called vernal ponds or ephemeral pools, are seasonal pools of water that provide habitat for distinctive plants and animals. They are considered to be a distinctive type of wetland usually devoid of fish, and thus allow the saf ...
s, wetlands, and other fresh to brackish water bodies. It is at least partially
aquatic
Aquatic means relating to water; living in or near water or taking place in water; does not include groundwater, as "aquatic" implies an environment where plants and animals live.
Aquatic(s) may also refer to:
* Aquatic animal, either vertebrate ...
, living in areas which are submersed much of the time. It also lives along muddy banks and in tidally-active areas of
estuaries
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environm ...
.
Conservation
It is listed as a vulnerable species in
Newfoundland and Labrador
Newfoundland and Labrador is the easternmost province of Canada, in the country's Atlantic region. The province comprises the island of Newfoundland and the continental region of Labrador, having a total size of . As of 2025 the populatio ...
. Cavan Allen rediscovered ''Crassula aquatica'' in Maryland in 2012 after it had been last seen in that state in 1950.
[https://nmnh.typepad.com/the_plant_press/2014/03/more-than-a-pygmy-discovery.html Allen Cavan and Wesley Knapp. 2014. More Than a ‘Pygmy’ Discovery. Plant Press Vol. 17 (Number 1)]
References
External links
Jepson Manual Treatment - ''Crassula aquatica''''Crassula aquatica'' - U.C. Photo gallery
aquatica
Aquatic plants
Flora of Northern America
Flora of Europe
Flora of Asia
Plants described in 1753
Taxa named by Carl Linnaeus
{{Crassulaceae-stub