Making New Friends

Rhodobryum ontariense (Kindb.) Paris
Photographer Blanka Shaw

If you are familiar with mosses from the eastern United States you may know the moss Rhodobryum. The rose moss, pictured on the right. It is a large, easily recognized, and charismatic moss that grows in forests. And I am in agreement with its name. It does look like a rose with many lush, green petals. 

So when I came across the moss below you could imagine that my initial reaction was that it looks like Rhodobryum, which is close but not correct. Rhodobryum does not live in California. It lives in the central and eastern US. It is Roellobryon. Rhodobryum, Roellobryon. You see where the confusion could arise. Not only in the name, but in the similarity of the plants.

Roellobryon roellii

One of the main features that distinguishes Roellobryon are the rugose leaves. This was a new term for me so I turned to my handy moss glossary and here is what it said about rugose. 

"rugose - (1) strongly wavy, wrinkled, or undulate crosswise (compare with undulate, somewhat wavy in one direction, corrugate, regularly or evenly wavy, folded, or wrinkled in one direction, striate, marked with lined or ridges length-wise, plicate, pleated, folded, or furrowed length-wise, and sulcate, strongly grooved, furrowed or folded lengthwise), (2) wrinkled in all dimensions." Malcolm & Malcolm 2006

Malcolm & Malcolm 2006

The photo that is included with the definition does a really good job of illustrating  the wrinkly nature of the leaves. Unfortunately the specimen that I was looking at was not very wrinkly at all when viewed under the compound microscope. The wrinkles that I did see looked to me just from the leaf being squashed under the cover slip. Not nearly as many wrinkles as shown here. But that happens. Variation across/among individuals. Biology is messy like that. Alternatively it may be that the rugose nature of the leaves is more visible on the dried samples, rather than wet ones under the microscope. 

I always enjoy making new species friends and this one was especially fun to meet. Keep an eye out for them when you are in California forests. They like to hang out on the humus underneath trees and shrubs. You never know when you might bump into Roellobryon. 

Roellobryon roellii