water liverwort

(Marchantia aquatica)

Conservation Status
water liverwort
Photo by Kelsey
  IUCN Red List

not listed

     
  NatureServe

NNR - Unranked

     
  Minnesota

not listed

     
           
           
           
           
           
           
           
 
Description
 
 

Water liverwort is one of the largest liverworts. It is found across North America and in Europe. It is found in permanently moist and intermittently wet areas in partial sun to medium shade. It grows on moist or wet soil in swamps, calcareous fens, wet meadows, cliffs, springs, disturbed areas, and recently burned areas. It often forms colonies of overlapping plants, sometimes creating extensive mats. The colonies are sometimes composed of all male or all female plants. It can be a pest if allowed to invade a greenhouse.

The vegetative body is a flat, lobed, ¾ to 4 long, ¼ to 4 wide plant body (thallus). The cells of a thallus are not differentiated into organs. It has no stem, leaves, vascular system, or true roots. The lobes are 1½ to 2 long, ¼ to ½ wide, up to 1 16 (1.5 mm) thick at the base, and thinner near the tip. The bases of adjacent lobes often merge together. The margins are wavy, untoothed, and green, not reddish or purplish. It has a dark, midrib-like furrow that is uninterrupted and conspicuous. It is not a true midrib because the thallus has no vasular tissue. The upper surface is bright green, opaque, and hairless. There are no scales on the upper surface. It is densely patterned with faintly indented, diamond-shaped areas (areolae). Each areola has a single, tiny, white-rimmed pore in the center. The areolae are very small and barely visible to the naked eye. The pores require a 10x hand lens to see. The underside of the thallus is very different. It is covered with colorless scales and has numerous large bundles of root-like filaments (rhizoids). Long wiry rhizoids attach the plant to the soil. Short, peg-like rhizoids absorb water. The plants is not aromatic, even when crushed.

Liverworts reproduce both sexually and asexually. The asexual reproductive structure of water liverwort is a splash cup (gemma cup) that is produced on the upper surface of the thallus. Gemma cups are almost always present and are produced on both male and female plants. The cups are green, circular, and shallow. Each cup has a few egg-shaped, 1 32 (1 mm) long gemma. The gemmae are dispersed when they are splashed out by raindrops. Each gemma can produce one or two plants if it lands on soil.

The male sexual reproductive structure (antheridiophore) is a short stalk topped with a flat disk that contains the male reproductive organ (antheridia). The stalk is to 13 16 long, purplish, and hairless. The disk resembles a flattened umbrella. It is flat and has 6 or 8 rounded lobes. Each lobe has a warty, purplish or grayish band of spores that radiates out from the center. The margins of the disk are translucent.

The female reproductive structure (archegoniophore) is umbrella-shaped. It consists of 8 to 11 narrow, green lobes radiating from the top of naked, purplish, 1½ to 2 long stalk. The lobes droop downwards, and the margins of the lobes are turned downwards. The underside of the lobe is lined with ovaries.

 
     
 

Height

 
 

Prostrate: ¾ to 4 long

 
     
 

Similar Species

 
 

Marchantia is the only genus of complex thalloid liverworts that creates cup-like gemmae.

Snakeskin liverwort (Conocephalum conicum) areolae are much larger and conspicuous, clearly visible without magnification. They give the thallus a snakeskin-like appearance. It does not produce gemma cups. The raised area around each pore is clearly visible without magnification, though to see the pore itself requires a 20x hand lens. When crushed, it is strongly aromatic. The archegoniophore is rarely produced and is cone-shaped, not umbrella-shaped.

Common liverwort (Marchantia polymorpha) is much more common. The dark, midrib-like furrow is incomplete and looks spotty.

 
     
 
Habitat
 
 

Moist or intermittently wet. Swamps, calcareous fens, wet meadows, cliffs, springs, disturbed areas, recently burned areas, and greenhouses. Partial sun to medium shade.

 
     
 
Ecology
 
 

Sporulation

 
 

July

 
     
 

Pests and Diseases

 
 

 

 
     
 
Use
 
 

 

 
     
 
Distribution
 
 

Distribution Map

 

Sources

24, 29.

 
  7/4/2023      
         
 

Nativity

 
 

Native

 
         
 

Occurrence

 
 

Uncommon

 
         
 
Taxonomy
 
  Kingdom Plantae (green algae and land plants)  
  Subkingdom Viridiplantae (green plants)  
  Infrakingdom Streptophyta (land plants and green algae)  
  Superdivision Embryophyta (land plants)  
  Division Marchantiophyta (liverworts)  
  Class Marchantiopsida (complex thalloid liverworts)  
  Subclass Marchantiidae  
 

Order

Marchantiales (complex thallose liverworts)  
 

Family

Marchantiaceae  
 

Genus

Marchantia  
       
 

It is likely that the species Marchantia polymorpha evolved from a hybrid between Marchantia alpestris and Marchantia aquatica. M. aquatica has a prominent and uninterrupted black longitudinal line in the middle of each thallus. M. alpestris lacks this line. M. polymorpha, the most common, is intermediate between the other two.

Some authorities consider M. alpestris and M. aquatica to be varieties of M. polymorpha, but this is not widely accepted. World Flora Online recognizes M. aquatica. ITIS considers M. aquatica to be a synonym of M. polymorpha. GBIF considers M. aquatica to be a synonym of M. polymorpha ssp. polymorpha.

 
       
 

Subordinate Taxa

 
 

 

 
       
 

Synonyms

 
 

Marchantia polymorpha var. aquatica

 
       
 

Common Names

 
 

water liverwort

 

 

 

 

 

 

 

 

 

Glossary

Gemma

In mosses and liverworts: A vegetative, reproductive cell or mass of cells that detaches from the parent and can develop into a new individual. Plural: gemmae.

 

Rhizoid

A filament arising from the lower stem of a moss, liverwort, or alga that anchors it to a substrate.

 

Thallus

In lichens: The vegetative body of a lichen composed of both the alga and the fungus. In liverworts: a flat, relatively undifferentiated plant body. Plural: thalli.

 
 
Visitor Photos
 
           
 

Share your photo of this plant.

 
  This button not working for you?
Simply email us at info@MinnesotaSeasons.com.
Attach one or more photos and, if you like, a caption.
 
 

Kelsey

 
 

I have females now too

 
    water liverwort      
           
 

this grows in my moss garden

 
    water liverwort      
           
 
MinnesotaSeasons.com Photos
 
 

 

 
           

 

Camera

     
 
Slideshows
 
 
     
     

 

slideshow

       
 
Visitor Videos
 
       
 

Share your video of this plant.

 
  This button not working for you?
Simply email us at info@MinnesotaSeasons.com.
Attach a video, a YouTube link, or a cloud storage link.
 
 

 

 
     
     
       
       
 
Other Videos
 
     
     
     

 

Camcorder

 
 
Visitor Sightings
 
           
 

Report a sighting of this plant.

 
  This button not working for you?
Simply email us at info@MinnesotaSeasons.com.
Be sure to include a location.
 
  Kelsey
6/17/2019

Location: Mound, MN

I have females now too

water liverwort  
  Kelsey
4/28/2019

Location: Mound, MN

this grows in my moss garden

water liverwort  
           
 
MinnesotaSeasons.com Sightings
 
 

 

 

 

 

Binoculars

 

Created:

Last Updated:

© MinnesotaSeasons.com. All rights reserved.

About Us

Privacy Policy

Contact Us