Moss names and taxonomy

Electrified Cat-tail Moss

For some moss enthusiasts, a term like Rhytidiadelphus triquetrus may as well read Τι στον κόσμο είναι αυτή η λέξη. It is the nine-syllable name of a moss, more easily skimmed over than translated, and far too technical and not especially useful for the lay person. However, a name like "Electrified Cat-tail moss" or "Big Shaggy Moss" would intrigue and inform — and perhaps entertain — the enthusiast, who would then know something about the size and possible shape of the moss.

Calliergon cordifolium - heart-leaved spear moss
Courtesy Koen Vandekerckhove

The bryologist, on the other hand, finds the Greek and Latin terms in moss names perfectly descriptive of things such as the growth habit, leaf formation around the stem, leaf color, or shape of the sporophyte or its parts. Calliergon cordifolium, for example, describes the heart-leaved spear moss. Climacium dendroides describes a tree-like moss.

Calliergon cordifolium
 Courtesy Michael Lüth

Moss naming conventions
In the world of bryology, only a handful of the 15,000* mosses have a common name, a few of which can be found at World of Mosses and Mosses, Lichens, and Liverworts of the Northwoods - Species Index.

Mosses are referred to by their Latin names at the genus and species level (a binomial). The bryologist or scientist who first describes the genus or species gets to names it.  There are instances, as with Bryoandersonia illecebra, in which the person naming the moss honored someone, in this case bryologist Lewis Anderson, but had to "Latinize" his name to fit conventions.

Any abbreviation after the genus or species name, as in Mnium thomsonii Schimp., indicates the person who first described the moss, in this case Wilhelm Phillipe Schimper, a French bryologist and paleobotanist (1808-1880). If a name appears in parenthesis, it is because his or her choice of family or genus or even species convention has since been modified by other scientists.

Taxonomy
Taxonomy is the science dealing with the description, identification, naming, and classification of organisms. There are a few biological classification systems, including:

• Linnean* — classified in a ranked hierarchy (list) based on structural similarities, developed before scientists understood that organisms evolved
• Evolutionary (or Darwinian) — grouped by how organisms are related through evolution and overall similarity
• Cladistic — grouped by an ancestor organism and all its descendents, as in a family tree of life

Linnean Classification
The USDA and the Natural Resources Conservation Service host a handy plant database where mosses are listed (classified) at every rank of the Linnean system.  An example is Bryum caespiticium, or sidewalk moss.

• Kingdom  Plantae – Plants
• Phylum (or Division)  Bryophyta – Mosses
• Subdivision  Musci
• Class  Bryopsida – True mosses
• Subclass  Bryidae
• Order  Bryales
• Family  Bryaceae
• Genus  Bryum Hedw. – bryum moss
• Species  Bryum caespiticium Hedw. – dry calcareous bryum moss

Mnemonic devices abound to help the novice remember the hierarchy of  

Kingdom, Phylum, Class, Order, Family, Genus, Species:

Kind Professors Can't Often Fail Good Students
King Phillip Came Over For George's Sake
Kings Play Chess on Fuzzy Green Squares
Keen Paleontologists Can Only Find Great Specimens 
Kiss Pigs Carefully Or Face Grimy Smiles
Kids Picking Cacti On Fridays Get Stuck
Keep Peeling Cold Onions For Good Smells 

Evolutionary and Cladistic Classification

Source: Wikipedia

A more modern classification systems look like a tree of life (as opposed to a ranked list), as depicted in this image by Ernst Haeckel (1834–1919).  This is the Tree of Life from Generelle Morphologie der Organismen (1866) with three kingdoms: Plantae, Protista and Animalia.


A cladogram is a diagram which shows ancestral relations between organisms (see below).  Mosses are found in the plants clade.

Source: Wikipedia

Carl von Linné, by Alexander Roslin, 1775.

*Who was Carl Linneaus?

According to Wikipedia, Carl von Linné, later given the more Latin surname "Linnaeus," was a Swedish botanist, physician, and zoologist, who laid the foundations for the modern scheme of binomial nomenclature. He is known as the father of modern taxonomy, and is also considered one of the fathers of modern ecology.







 *Counts vary, depending on the source, from 9,000 to 22,000.

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 Read about the shrinking number of fungus and lichen taxonomists in the UK:
"The Fungus Among Us Multiplies As Mycological Taxonomists Wither" Wall Street Journal, September 7, 2011