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Bristleworm Factsheet (fwd)

Geoffrey Read Geoffrey.Read at actrix.gen.nz
Sat Apr 27 19:44:38 EST 1996

I picked this up from a Usenet aquaria group. I have not altered it. It's
well-intentioned, and an entertainingly different perspective of our
favourites. However, maybe I'd like to disagree with him in places. As
far as I know Michael Noreen is not an Annelida subscriber. Feedback to
the list please, and to Michael of course. GBR

Bristleworm Factsheet and FAQ.

From: Michael Noreen <ev-michael at nrm.se> 
Date: 1996/04/04

organization: MolSystLab, Naturhistoriska Riksmuseet.

newsgroups: rec.aquaria.marine.reefs
x-mailer: Mozilla 2.01 (Win95; I)

Here's the bristleworm FAQ I promised to write earlier. Suggestions
and corrections eagerly awaited.

The Bristleworm Factsheet and Mini-FAQ v0.91 (4apr96) by Mike Noreen


    About the Author
    Various disclaimers and copyright information

    I. The bristleworm Factsheet
         1. What is a bristleworm?
         2. Sedentary bristleworms.
         3. Errant bristleworms.
         4. The Bad Boys.
         5. The Fireworm (additions welcomed).

    II. The Bristleworm Frequently Asked Question.


So you've set up a reef tank, with lots of live rock, corals, fish and nice
live rock. You sit back to admire your work, when a strange centipede-like
creature suddenly crawls out from under a rock. What is it? Is it
dangerous? Should it be killed? How? Is it Bleach-and-Boil time? Relax. The
cavallery is here with some answers - I give you the Bristleworm Factsheet
and Frequently Asked Questions. Everything you've ever wanted to know about
bristleworms, and then some.


At the time of writing this I'm a biology student, specializing in marine
evertebrate systematics, at Stockholm University. I work at the Molecular
Systematics Laboratory at the National Museum of Natural History in
Stockholm, under dr Ulf Jondelius, one of the worlds foremost authorities
on flatworms.  Aquariums are my hobby, and I've some 20 years experience in
the field, 10 years with reef tanks.

Contacting the author with questions/suggestions/bug reports: email to:
        ev-michael at nrm.se
        or (preferrably)
        radharc at karkis.canit.se


Legal stuff: This text is (c) Mike Noreen, but may be freely reproduced for
non-profit purposes as long as it is not altered in any way and the authors
name is not removed. Commercial use of this text (ie in publications)
require the written consent of the author.

Disclaimer: This text is as accurate as I could make it without getting
_too_ long, but I'm only human, and there will be errors in it. I am not
responsible for any actions or losses or altered mental states resulting
from the reading of this text or following advice given in it.


1. What is a bristleworm?
    The phylum Annelida (ringworms) is divided into three classes: the
Oligocheta (earthworms and their allies (ie tubifex)), the Hirudinea
(leeches), and the Polychaeta (bristleworms). By far the biggest class is
the polychaetes, with over 8000 species in atleast 80 families - and more
species are described every year. Almost all polychaetes live in the sea,
although a few also can be found in freshwater and in moist soil. They are
extremely diverse, ranging in size from 1mm to in excess of two meters in
length, and are abundant in all biotopes in all seas around the world. In
fact, together with crustaceans their role is reminiscent of that of
insects on land, forming the base of the foodweb. Several species, mainly
of Errant polychaetes, are used as fishing bait (ie the sand/lugworm).

>From an aquarists point of view, for purposes of identification,
bristleworms can be crudely divided into Errant and Sedentary species
(please note that this is not systematically correct. This division does
not in any way reflect relationship, but is purely utilitarian).

Sedentary bristleworms stay in one place, are typically tube-builders and
feed by filtering mikroplankton with their often brightly coloured
retractable tentacle crowns. Common in our tanks are for example Peacock
worms pertaining to the family Sabellidae.

Errant bristleworms actively move about in search of food, which may be
other small vertebrates, algae, corals or almost any organic matter
depending on species. Errant bristleworms usually resemble centipedes in
general appearance, and have strong jaws.

Bristleworms normally reproduce sexually, usually with planktonic larvae.
Only about 30 out of 8000 species reproduce asexually by fission.

2. Sedentary bristleworms. 

These guys are common and usually welcome inhabitants in reef tanks.
Roughly they can be divided into two different types: those with fan-like
feeding apparatuses and those with tentacle-like feeding apparatuses
(again not a systematically correct division, but useful for
identification). They all feed on small organic particles and detritus,
and are totally harmless to other inhabitants in the tank. They all have a
burrow or tube which they withdraw into when they feel threatened. A lot
of animals, evertebrates as well as fish, feed on them.

        Sedentary with fan-like feeding apparatus:
                a) Peacock worms (any species belonging to the family
                Sabellidae). Recognisable by their soft, leathery, tubes
                made of mud and mucus. Worms of this family are often sold
                in petshops. They require good quality water to thrive, but
                are not photosynthetic. They occasionally scare their
                owners by shedding their brightly coloured crown of
                tentacles - don't worry, it grows back. However, if the
                worm leaves its tube it's dying and should be removed (and
                water parameters should be checked). They sometimes
                reproduce in aquaria, but not so to become a problem.

                b) Christmas tree worms and allies (several families, ie
                Spirorbidae, Serpulidae). Very similar to Peacock worms,
                but living in limestone tubes and sometimes burrowing in
                limestone (the familiar Fan worms of living rock). Of
                particular interest are the Serpulidae and Spirorbidae
                families, which may have sudden population explosions in
                the tank. Serpulids are bigger than Spirorbids, and live in
                irregularly shaped tubes, while the Spirorbid tubes are
                small, white, tightly coiled spirals (spiral less than 1cm,
                often just a few mm, from side to side). They may
                proliferate to the point that they become a nuisance,
                clogging tubing and covering the glass, but usually these
                explosions are over as quickly as they started.

       Sedentary with tentacle-like feeding apparatus:
                Here we find a bunch of worms sometimes difficult to even
                identify as worms. Common in reef tanks are the Spaghetti
                worms and Sand Mason worms belonging to the family
                Terebellidae. They hide their bodies (which are quite
                large) in cracks in/under stones, and all that's visible
                are the numerous, sometimes 30cm long, narrow, transparent
                tentacles. The tentacles work as conveyor belts, bringing
                detritus to the worm on which it feeds. Other extremely
                common but rarely noticed worms belong to the family
                Spionidae. They are small, burrow in limestone (and snail
                shells), and all that's visible of them are two short

3. Errant bristleworms.
    The real problem childs in tanks. They are ugly, move in an unnerving
manner, can pack nasty poisonous bites and/or poisonous bristles, and may
eat things the aquarist would not like them to eat. In general appearance
they resemble centipedes (although the 'legs' are not true legs, and they
are not related to centipedes), and are always present in all tanks with
live rock or live sand. They are of varying colour, size and disposition,
and a great number of families and even greater number of species are found
in aquaria. It is very common for errant polychaetes to be opportunists -
eating algae, scavenging, or killing small evertebrates as they find it.
Despite their omnivorous habits the vast majority of species are totally
harmless in a reef tank. A very few species may, however, cause problems.

4. The Bad Boys. 
Errant bristleworms cause problems in two ways: either by becoming so big
that they can attack things they normally would not be able to harm (ie
fish or aquarists fingers), or by being predators/parasites on valuable
inhabitants in the aquarium.

    Bad because of size: Basically a bristleworm larger than, say,
    two-three inches can deliver painful bites, and conceivably kill fish,
    shrimp etc.  Some species also have poisonous bites, and although I've
    never heard of anyone dying of bristleworm-bite, there's no doubt they
    could seriously inconvenience a sensitive person (normally a bite from
    a poisonous species, ie a Glycera, is comparable to the sting of a
    wasp). Use caution (and/or tweezers) when dealing with a large worm.

    Bad because it's a specialized predator/parasite: Actually very few
    bristleworms are parasites, and none on vertebrates, so the fish are
    safe (except for very large very hungry predatory worms). Some species
    do eat corals, and may cause problems. The most known coral-eating
    species is the Fireworm.

5. The Fireworm (additions welcomed):
The Fireworms are a group of coral-eating worms from the Caribbean, common
in shallow waters. In general appearance a fireworm is fat, fatter than an
earthworm, reddish-brown, with prominent tufts of white-to-green bristles.
They can multiply rapidly, and can in a short time kill all corals in a
tank. They have gotten their names from having poisoned bristles, which
cause skin irritation. Handle with care.  Various methods have been
suggested to remove Fireworms. These include:  commercially sold traps,
mechanical removal with tweezers, putting something tasty (ie shrimp meat)
in old nylon stockings in the tank overnight. The worms become entangled in
the nylon, and can be removed in the morning. If I sound somewhat vague on
fireworms, that's because I've never even seen an actual fireworm.


Q: My peacock worm has left it's tube. What's happening?
A: It's dying. Remove it before it rots. Its death may be a sign of poor
water quality.

Q: My peacock worm has lost its head! Is it dying?
A: Nope. It's just shed its old worn tentacle crown. A new crown will grow

Q: How much light does my peacock/christmas tree/fan worm require?
A: None. It's a filter feeder - it's not photosynthetic.

Q: How should I place my peacock/christmas tree/fan worm?
A: They like moderate current. They dislike too strong current.

Q: I've found this centipede-like worm in my tank - is it dangerous?!
A: With 99.9% probability not, unless it's more than 2-3 inches in length
OR very fat, reddish brown, with white or greenish bristles, and there's
live rock from he Gulf/Caribbean in the tank. Remember: there are ALWAYS
bristleworms in ALL tanks with live rock, and they're nearly always

Q: I've got one/several 'bad' bristleworms in the tank - how do I kill
A: Four ways:   *Get a commercial bristleworm trap. Not all work
                *Pluck them out/cut them in two with tweezers. If divided
                in two it will NOT grow back into two worms, although the
                head end MAY sometimes grow a new tail. *Put something
                tasty, ie shrimp or mussel meat, in a nylon stocking, and
                place on the bottom of the tank over night. Bristleworms
                who try to eat the meat become entangled in the nylon, and
                can be disposed of in the morning. *Get a bristleworm
                predator, ie an Arrow crab. Problem is that they don't know
                that you want to keep some bristleworms, like the
                Peacock/Christmas tree worms, but eat all worms.

Q: Why not kill the worms by boiling the live rock, or with cupper
sulphate, or with fresh water, or with bleach?
A: Because all of the above are guaranteed to kill the beneficial bacteria
in the live rock, which is the reason one keeps live rock to begin with.
You might aswell throw the live rock/sand away as try the above. Chemical
control of bristleworms is basically only an option in fish-only tanks.

Q: What's this hard, white, organism that's growing on the glass of the
A: If it's a tightly coiled spiral its the tube of a Spirorbid, else
probably a Serpulid, bristleworm. Harmless filterfeeders, but may go
through population explosions. Usually they disappear as the tank ages.

Q: There's weird _long_ translucent tentacles coming out of my live rock!
What is it? 
A: It's the tentacles of a detritus-feeding Terebellid
bristleworm. Totally harmless, quite long-lived, and extremely ugly, even
for a bristleworm, should you ever see the actual worm (which is probably
the size of your thumb!).

Q: There's lots of small parasitic bristleworms all over my soft corals! 
A: Take out the coral, and mechanically remove all the worms by washing
the coral in salt water. Repeat as necessary.

Q:My tank has been set up for several years, and I've now found
bristleworms. Should I be worried?
A: No. If they've caused no damage after a year, chances are they never


MVH: Mike Noreen    Internet: radharc at karkis.canit.se
                        FIDO: 2:201/411.14


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