The Bug Mosses - Buxbaumia sp.

This was one of the interesting mosses that we saw on the Bioblitz a couple of weeks ago. It is a member of the genus Buxbaumia and is most likely Buxbaumia aphylla. There are 4 species in this genus that can be found in North America and this is the only species one of the four that has been found in Connecticut. If you are hiking just a little further north in Massachusetts you might run into both B. aphylla and B. minakatae. The way to tell these two apart are by the following sporophyte features, which are mature in the springtime.

Buxbaumia aphylla
- Capsule glossy/shiny
- Capsule with a ridge separating the Upper side from the Lower

Buxbaumia minakatae
- Capsule dull
- No ridge. Upper and Lower sides gradually merge.

The shiny capsule can be better seen on the second photo. It looks pretty dull in the first, but I think that is just the lighting. Both of the photos show the lighter upper side of the capsule that is bordered by a ridge that separates it from the lower side.

The common name for mosses in the genus Buxbaumia is the bug moss. This name refers to the off-kilter (asymmetrical) sporophyte capsule that kind of resembles a bug.

Another fact of note about members of Buxbaumia is that they have a very reduced gametophyte. They never form a leafy plant. Instead they have persistent protonema, which consists of thin filaments that may remind you of algae, if only you could see them. These protonema do produce sex organs (antheridia and archegonia). Add a little water to the mix and a sporophyte is produced via sexual reproduction. Since there is no leafy gametophyte for Buxbaumia the sporophytes appear to be sticking out of the bare soil as you can see in the photo below. Most mosses have a persistent gametophyte that is large and the sporophyte stays attached to it through its life. Since it lacks this feature this makes Buxbaumia a bit of an odd-ball.


If you have ever seen insects displayed in a natural history collection or museum they are mounted on pins stuck through their body and then poked into the bottom of a lined box. That is what I think the Buxbaumia sporophytes resemble. Specifically, they remind me of stink bugs, which one of my former office-mates studied for his dissertation. Keep your eyes peeled for this cool moss the next time you are out walking. They are a nice little find.