Snakeskin liverwort is common and easily recognized. The thallus (main body) looks like large, flattened, irregular, overlapping straps. The surface is covered with polygon-shaped air pores, giving it a bubbly appearance similar to snakeskin. There is a pale dot in the center of each air pore. The edges of the thallus are wavy and tend to curve downward. If you scratch the surface of this liverwort, you may notice a distinctive spicy scent, and that aroma is one of the key ID features.
The antheridia (sperm-producing structures) are fairly obscure and look like warty spots on the top of the thallus, near the outer tips; they develop and shed sperm in the fall. The next spring, the fertilized archegonia (egg-producing structures) are quite noticeable, resembling small mushrooms with conical heads (Conocephalum means “conehead”). The archegonia are supported on a light green, watery stalk and are short-lived. Antheridia and archegonia usually are formed on separate individual plants.
Snakeskin liverwort is a good example of a thallose, or thalloid liverwort. These are the form of liverworts most people are familiar with. They look like green ribbons or scales that grow flat against a surface, typically branching in a Y-shaped pattern. There are no clearly defined stems or leaves.
Liverworts, like mosses, are land plants that do not have a vascular system. This lack of veinlike tubes to conduct moisture and nutrients throughout the plant limits them to a small size. They produce spores instead of seeds. Their form of reproduction usually requires them to be in wet or moist places.
Learn more about liverworts on their group page.
Similar species: Missouri has about 19 genera, in 12 families, of thallose liverworts. Snakeskin liverwort is one of the most common.
The other most common thallose species is umbrella liverwort, Marchantia polymorpha. Unlike snakeskin liverwort, its thallus turns up at the edges; the netlike pattern on the upper surface is less deeply indented and less noticeable; it commonly has cuplike gemmae on the upper surface (while snakeskin liverwort lacks gemmae cups); the antheridia are stalked, with a flat, circular top with lobed or deeply scalloped edges (not sessile and wartlike). The archegonia look like small mushrooms at first, but at maturity they open to produce fingerlike projections radiating from the central stalk (looking like tiny palm trees). In addition to damp, shady areas in nature, it is also fairly common in gardens and greenhouses.
Thallus width: about ½–¾ inch; length to about 6 inches.
Statewide.
Habitat and Conservation
Found on very moist soil or rocks, in rather shady areas, often in the splash zone of creeks, near springs, and at the bases of cool, moist cliffs. Compared to the similar umbrella liverwort, snakeskin liverwort is more often found in natural settings, while umbrella liverwort often lives in disturbed habitats and greenhouses.
Status
One of the most common and recognizable liverworts in Missouri.
Taxonomically, this liverwort was long called Conocephalum conicum, but researchers determined that in Europe, C. conicum was actually two different species, C. conicum and the wide-ranging (Holarctic) C. salebrosum. The latter is what occurs in North America. C. conicum lives in Europe but apparently does not occur here.
The new species name, salebrosum, created in 2005, means rugged, rough, or uneven. It apparently refers to the bumpier, more uneven, less shiny surface texture of the thallus in species C. salebrosum compared to the smoother, shinier surface of species C. conicum.
Life Cycle
The liverworts we usually see are only one part of a two-part life cycle. This conspicuous part of the cycle, called the gametophyte (gamete-bearing plant), produces sexual reproductive structures: sperm-bearing male structures called antheridia (singular antheridium) and egg-bearing female structures called archegonia (singular archegonium). In snakeskin liverwort, the antheridia and archegonia usually occur on separate plants. Also, the sperm are not enclosed in pollen grains; they must swim through water to reach the archegonia.
The united sperm and egg develop into the second part of the life cycle, the sporophyte (spore-producing plant). The sporophyte develops within the archegonium and eventually pushes beyond it. The sporophyte develops a capsule in which spores form. When the sporophyte is mature, it sheds spores into the environment to develop into new gametophytes.
Asexual (vegetative) reproduction is very common in liverworts. As the gametophyte grows and branches, older parts die off and the branches continue as new plants. They can easily grow by cuttings, too. Floods can distribute fragments of liverworts downstream, creating new colonies.
Human Connections
Snakeskin liverwort is strange and beautiful. It and the ferns and mosses that share its cool, streamside habitats make those places inviting for heat-weary Missourians in midsummer.
Globally, some liverworts have been used medicinally. The names “liverwort” and “hepatic” both came from the antique and outdated belief that they could be used to treat liver ailments, based solely on the liverlike shape of the plants. Meanwhile, modern researchers have studied extracts of snakeskin liverwort for possible antibiotic use.
Now is a great time to learn about liverworts and mosses, because there is so much information available online. Before the Internet, you needed access to heavy reference manuals and scholarly journals, whose pictures were limited by publishers’ budgets. Today, photographs abound, and information is available at all skill levels.
Ecosystem Connections
Along streams, snakeskin liverwort and its mossy compatriots help to bind soils and prevent erosion. They provide hiding places — a miniature habitat — for numerous types of insects, earthworms, snails, mites, springtails, water bears, and other tiny animals to live. Shrews, salamanders, frogs, tiny snakes, and other insectivores hunt for a variety of small animals in these microhabitats.
This is apparently one of the liverworts whose spores are large enough to be distributed, to some degree, by insects, springtails, and maybe even shrews and mice.
Mosses, liverworts, hornworts, and lichens seem rather similar, but these organisms are in very different groups. Mosses, liverworts, and hornworts are small, low plants usually found in damp habitats. Unlike more familiar plants, they lack veinlike structures and do not produce flowers or seeds — instead, they produce spores. Meanwhile, lichens are not plants at all: they are a collection of different fungi that have photosynthetic algae living within their tissues.