Hippuris

Scientific name

Hippuris L.

Common names

mares-tail

Family

Plantaginaceae

Similar genera

Ceratophyllum, Hydrotriche, Myriophyllum

Native distribution

Northern Hemisphere

Species cultivated

Hippuris vulgaris L.

Adventive distribution

none

Weed status

occasionally considered weedy in its native range due to overgrowth blocking waterways

Habit

submersedsubmersed:
see submerged
and emergentemergent:
(adj) (syn. emersed) with parts raised out of the water; extending up out of the water
attached stem plantstem plant:
(n) (a term used in the aquarium and pond plant trade) having an elongate stem (as opposed to a compact stem)

Brief description

Perennial. Creeping rhizomerhizome:
(n) an underground stem, usually growing horizontally, from which both roots and shoots emerge directly; the thick, above-ground stem of ferns
with erect leafy stems. Leaves equally spaced along stem in whorls of 8-15, sessilesessile:
(adj) attached directly, without a stalk
, obovateobovate:
(adj) ovate, with the narrow end at the base
to linear, entireentire:
(adj) having a continuous margin that is not toothed or lobed
. Flowers sessilesessile:
(adj) attached directly, without a stalk
or subsessile, axillaryaxillary:
(adj) in, of, or produced from an axil
, either bisexualbisexual:
(adj) having both male and female sexual reproductive structures on one individual or in one flower
, unisexualunisexual:
(adj) (of a flower) with either stamens (male) or pistils (female) but not both; consisting of only male or female flowers
or sterilesterile:
(adj) lacking male and/or female reproductive parts; not producing fruit, seed, pollen, spores, etc.
; sepals and petals greatly reduced to rim above ovaryovary:
(n) a hollow organ at the base of the carpel of a flower in which ovules are produced
. Dispersal by seed in ‘nuts’ and stem fragments.

Natural habitat

swamps, ponds, and lakes

Additional comments

Two species are known. Hippuris vulgaris is cultivated for ponds and is highly variable geographically. Previously placed in its own monotypicmonotypic:
(adj) represented by a single example (species)
family, recent molecular studies have shown H. vulgaris is more accurately placed in Plantaginaceae.