#marchantia

This weeks microscopy features Marchantia polymorpha (Marchantiaceae), a species of thallose liverwort! Called the ‘common liverwort’ this species is probably the most well known of thallose liverworts. It is found on every continent except Antarctica and is used as a model organism. It can often be a horticultural weed and is very commonly seen in potted plants at nurseries. Which is exactly where I picked up this specimen. I had bought tubestock of an Acacia specifically for the reproductive Marchantia it contained, not actually for the Acacia.

There’s a few features I wanted to share (and part of why I got soooo excited when I saw this plant).

First off, air pores! These are almost the equivalent of stomata in higher plants. Their function is in gas exchange and they are those pin-prick like features surrounded by a whitish circle.

Next, a gemmae cup! For Marchantia these cups are circular (as opposed to crescent-shaped like in Lunalaria). Gemmae cups house asexually-produced gemmae that disperse via water. You can just make out some of them in the centre here.

Now we have my two favourite photos from the whole shoot. These are archegoniophores, which contain the female sex organs. They're stalked and tall and just stunning. Let's look at their underside.

These are mature sporophytes on the underside of the archegoniophore. They're orange/yellow and actually look like mini flowers or something. You can just make out the feathery fine threads of spores on the first image there. They're gonna go off and make the next generation of Marchantia.

Lastly we have an antheridiophore. These contain the male sex organs. There was only one on the specimen I got but thankfully it worked out, it wasn't too old to get goof photos of.

Marchantia sp. antheridiophores.

Growing in delightful abundance next to the Visitors Centre at the Craters of the Moon. Probably the Common Liverwort Marchantia polymorpha, which is found in damp and sometimes submerged habitats everywhere except Antarctica. Hardy enough to be a horticultural weed, and potentially a problem in caves with artificial light, and frequently the first plant to occupy burned areas.

Dioicous, having separate male and female plants. The umbrella-shaped ones in the top photo are female - male plants have smaller bits. But Marchantia can also spread asexually via gemmae - clumps of cells contained in cup-like structures on the upper surface of the plant until splashed out by rain, or when older parts of the plant die off and the newer branches develop into independent plants.

Have some funky irish lads (submitted by @ash-n-fire)

this is, and i cannot stress this enough, the wildest configuration of the famous common thalloid liverwort species marchantia polymorpha (at least im like….85% sure that’s what it is) ive ever seen. the little weird umbrella-looking things are…..yes, indeed……The Sexy. there are male and female sex umbrellas, with each plant producing only one kind (you won’t find male and female organs on the same plant):

Lebermoose.