It’s not uncommon for readers, friends, andfriends-of-friends-of-friendstosend me an email asking me to identify whatever plant they just bought or
got in a trade. Usually I am happy to help
them out if I can—and I can almost always
at least point to the right genus, if not a
There is, however, a major exception to
that, and that exception is something of an
aquatic plant identifier’s four letter word:
Now I love mosses as much as the
next hobbyist. They’re versatile, easy to
grow, and can spruce up even the most
haphazard of tank layouts just by virtue of
their presence. Mosses are a great feature in
any tank, “planted” or otherwise. It’s just
that being asked to identify them always
makes me feel as if I’m letting people down.
Why is that? As I recently wrote to
the last person to ask me for a moss ID,
it’s nearly impossible to distinguish moss
species without access to a microscope at
the least—info on their growth patterns
can suggest a possible ID, but those
growth habits vary with different growing
Mosses are a bit different from other
plants in the first place—they (along with
their cousins, liverworts and hornworts—
no relation to the vascular aquarium plants
in the genus Ceratophyllum, also called
hornworts) have their own dedicated
field of study, called bryology; they are
mainly distinguished based on microscopic
characteristics (i.e., leaf tips, the shapes and
sizes of spores, cellular structure, etc.) and/
or DNA analysis. Unlike vascular plants,
which have different types of tissues and
structures to enable functions like nutrient
transport and the control of water loss, the
nonvascular mosses have fewer types of
tissues and a very narrow list of structures.
Add all that to the fact that most common
aquarium mosses are close relatives within
a mere handful of genera (and as a result
have similar microscopic characteristics)
and it’s pretty much blind guessing unless
your plant came directly from a reputable
horticulturist or you happen to have a good
microscope, some herbarium specimens,
and/or a DNA sequencer lying around.
Will the Real
Please Stand Up?
The largest grouping of mosses in the
hobby hails from the family Hypnaceae.
This family includes the two very closely
related genera Taxiphyllum and Vesicularia,
from which hail the ubiquitous Java moss
(T. cf. barbieri) and popular Singapore
moss (V. dubyana). Other fairly well-known
representatives include Taiwan moss (T. cf.
alternans), peacock moss (Taxiphyllum sp.),
flame moss (Taxiphyllum sp.), Christmas
moss (V. montagnei), and weeping moss (V.
ferrei). Rarer species include erect moss (V.
reticulata) and mini Taiwan moss, currently
the hobby’s sole representative from the
Interestingly, you will find many older
references that list Java moss as V. dubyana.
That was long thought to be the correct
name until a comparison with herbarium
specimens led to a tentative ID as T.
cf. barbieri (note that the abreviation of
“cf.” in a binomial name indicates that
the ID of the following name is not
absolutely confirmed, usually due to a
lack of seed/spore samples where plant
names are concerned). This identification
remains tentative because the Java moss
Mystery Mosses: An ID Conundrum (Or, “Why
Amanda Can’t Tell You What Moss That Is”)
Amanda Wenger is a lifelong hobbyist who
inherited a love of aquaria from her father,
when he gifted her with her first fish at age
two. A decade and a half later, she started
putting plants in the fish tanks and was
hooked. Today, she lives in Connecticut,
where she’s the current President of the CT
Aquatic Plant Enthusiasts (CAPE) and,
with the assistance of her family, maintains
a well-planted fishroom and a hobby-sized
greenhouse filled with aquatic plants.
She’s also part of the moderating staff at
AquaticPlantCentral.com. Aside from the
aquarium hobby, Amanda is a professional
illustrator and graphic designer with a soft
spot for wildlife illustration.