Callitriche

Scientific name

Callitriche L.

Common names

starwort

Family

Plantaginaceae

Similar genera

Chamaegigas, Didiplis, Elatine, Micranthemum, Microcarpaea, Potamogeton

Native distribution

cosmopolitancosmopolitan:
(adj) essentially worldwide in distribution

Species cultivated

Callitriche heterophylla Pursh

C. palustris L.

C. stagnalis Scop.

C. verna L. [synonym of C. stagnalis Scop.]

Adventive distribution

cosmopolitan cosmopolitan:
(adj) essentially worldwide in distribution
distribution makes determination of new introductions difficult

Weed status

rarely weedy in rice crops

Habit

submersed, floating, delicate stem plant

Brief description

Annual or perennialperennial:
(adj) (of a plant) having a life cycle of more than two years
. Stems elongate when submersedsubmersed:
see submerged
or compact when emersedemersed:
see emergent
. Leaves oppositeopposite:
(adj) (of leaves) two leaves per node; in pairs on opposite sides of an axis
, decussatedecussate:
(adj) arranged along stem in pairs, with each pair at right angles to the pairs above and below
, in a terminalterminal:
(adj) at the apex
rosetterosette:
(n) a radiating cluster of leaves, usually close to the ground at the base of a plant
when floating, sessilesessile:
(adj) attached directly, without a stalk
; leaf bladeblade:
(n) (syn. lamina) the flat, expanded part of a leaf, frond, or petal (excluding, e.g., the petiole)
linear to oblongoblong:
(adj) two to four times longer than wide, with +/- parallel sides
to spathulatespathulate:
(adj) (or spatulate) spoon-shaped
, only midveinmidvein:
(n) the primary, usually central vein of a leaf or leaflet
prominent; apexapex:
(n) the point farthest from the point of attachment; the tip (often pointed)
often (unequally) notched; marginmargin:
(n) edge; rim
entireentire:
(adj) having a continuous margin that is not toothed or lobed
. Flowers minute, solitary, axillaryaxillary:
(adj) in, of, or produced from an axil
, unisexualunisexual:
(adj) (of a flower) with either stamens (male) or pistils (female) but not both; consisting of only male or female flowers
; petals and sepals absent; male flower with a single stamenstamen:
(n) the male reproductive organ in a flower, consisting of a pollen-bearing anther and a filament
as an elongate filamentfilament:
(n) the stalk of the stamen, which supports the anther
with reniformreniform:
(adj) kidney-shaped
antheranther:
(n) the pollen-producing, apical part of the stamen
; female flower with 2 elongate styles. Dispersal by stem fragments or seed.

Natural habitat

lakes, ponds, and slow flowing rivers

Additional comments

Callitriche is comprised of 63 species distributed worldwide. Some species have been used as indicators of water quality as they may be sensitive to pollutants and aggressive competition from introduced plants.