A Few Botanical Details for the Non-Botanist on how to tell the difference between a Moss and a Liverwort.

How can you tell if a plant is a moss or a liverwort?

Some liverworts like those belonging to the Marchantia family are quite distinctive, and most people would think they know what a moss looks like, because many of them have spikey leaves.

But there are exceptions to every rule and there are some which require microscopic examination, or the use of a hand-lens, to tell whether it is a moss or a liverwort. Also, to tell one species of moss from another, or one species of liverwort from another, using a microscope is often the only way.

1. Have a close look at the leaves - with a hand lens or a microscope (up to 100X will do fine). If you can see what looks like a vein or "nerve", then it is probably a moss. But some mosses have a very short nerve, just to be tricky. And then there are some liverworts, belonging to the Pallavicinaceae family, which have midribs ("nerve").

2. Have a close look at the edge of the leaf. If it has lobes, or very fine points (cilia), it is a liverwort. Mosses can have very fine serrations, but not lobes. (However there are a couple of NZ mosses which have cilia.)

3. Look at the main leaves - if they are nerveless and arranged in two rows, the plant is probably a liverwort. The plant to the right is a liverwort (Plagiochila banksii) - no leaf nerves, the leaves have fine points and are arranged in two rows.

This plant to the right (Achrophyllum dentatum) is a moss. It's leaves look like they are flattened into two rows, but in fact they are spirally arranged around the stem. Its leaves also have a short nerve, which you need a microscope to see.

And then you find plants like the Pallavicinia species and it's relatives Symphogyna species, who have a "nerve" in their leaves.

But they are liverworts. Confused??

4. Another difference between mosses and liverworts is with the sporophytes.

Probably everyone who has seen a moss plant has also noticed little things that look like a seed pod on a stalk sticking out above the leaves. That thing is a "sporophyte", a part of the life cycle of all mosses and liverworts.

If you find a "mossy" plant with what looks like a "seed pod" (known as a capsule) on a "stalk" (seta) then have a closer look at both the capsule and the seta.

Moss capsules open at the end to let the spores out, and when you look closely (with some magnifying device) you can see teeth around the opening.

Mosses also have a strong green or brown seta.

Liverwort capsules split along the sides, often into 4 parts, to spread the spores.

When you look at the seta of liverworts they are thin, white or translucent, and quite weak.

The problem with using sporophytes as an identification aid is that they are only visible for certain times of the year, mainly spring and early summer.

The liverwort sporophytes are usually around only for a few weeks.

For more sporophyte shots, look here

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