"What is that thing? That biological dusting fan? A worm!?"
By some estimates there may be more species of "worms" than insects! Most of the large groups, the phyla of Roundworms (Nematoda), Flatworms (Platyhelminthes) and Segmented Worms (Annelida) are barely known to most of us. The very common and important other "wormy" groups are virtually unknown. We use these organisms consciously as food, to help keep our substrates from compacting and channeling, as filter-feeding "cleaners" in marine reef systems and dook it out with them as disease carrying and causing parasites and competitors.
Why the lack of respect? What is this, another example of species-centricity? Worms are everywhere; in your hair, in the air, in the deepest seas, warmest waters, driest deserts... Doing everything: parasitic, free-living, filter-feeding planktivores, detritivores, ferocious predators, sneaky vacuum cleaners...
Yes, worms are wormy; often slimy, reclusive, mysteriously appearing and disappearing. But they were here first! All major and minor worm groups were on the planet in full force before the Cambrian. They are still critically functioning as aerators, facilitators of decomposition and general energy transfer/recycling and as store houses of food energy and webbing themselves. Let's use this brief article to discuss one phylum of worms often encountered on purpose and accident by marine hobbyists, Polychaete Annelidans:
In the world of zoological taxonomy feather dusters, duster-cluster, bristle, fire, fan, tube...worms are grouped/placed in the Annelida, generally known as the "segmented worms", in reference to their metamerism or segmented appearance.
This segmentation allows for different types of locomotion, several environments. External and internal segmentation is obvious in the body, parapodia (lateral processes), nervous, muscular, excretory and circulatory systems arranged in repetitive placement.
There are three living Classes:
1) Oligochaeta, meaning "few bristles", the ubiquitous "earthworms" that indeed do have small body bristles.
2) Hirudinea, the leeches. All basically parasitic.
The above two are mostly freshwater and terrestrial and differ generally in basic ways in terms of internal anatomy, having permanent gonads...unlike the
3) Polychaeta ("many bristles"), some are downright prickly, are mainly marine. They have a head end (prostomium) with a typical sensory array of tentacles, papillae, eyes... and a posterior segment (pygidium). New sections are added right before the pygidium. What else? longitudinal muscled bands effect motion through contracting against a fluid filled body cavity (coelom). The digestive tract is a more or less straight tube running from the anterior mouth to the posterior anus. Most do have a "closed" circulatory system, blood and a "heart", an anterior dorsal ganglionic mass (brain), lateral nerves in each segment, blah, blah, blah. And they're neat! Some are big (larger than your hand, longer than your fish. And here, fellow pet-fish commandos, I must confess to a certain period of intransigency when even I lived on the public largesse. For a couple of years in grad. school I did "environmental" work sorting and identifying benthic marine invertebrates, principally polychaete worms. My dear cubicle mate actually had a beautiful graphic of a Glycerid polychaete worm with double everted jaws (shades of Aliens I and II & III), multiple eyes and specialized parapodia with a blasphemous label "God is a Polychaete!
There are so many species of polychaetes occurring most everywhere in marine environments with known life "habits" that much can be discerned by collecting, i.d.ing, counting 'em up and measuring now and later to determine "impact" of human or other activity.
So yes, money can be made with life science degrees! My roomie used to do Errantiates and I'd get stuck with the Sedentariates. Hey, what are they!? Glad you asked; back to the story at hand:
Polychaetous Annelids are sub-divided into two sub-classes:
Sedentariate Polychaetes/Featherduster Worms... On Parade!
Family Sabellidae: Fanworms. Non-calcareous tubes produced that they live in, feed from. Filter feeders who retract their tentacular crowns when alerted. Often found attached to dead coral, or in sediment with part of tube exposed. Collected most often in "polluted" harbors in mud/muck. Includes genera: Bispira, Sabellastarte,
Family Serpulidae: Calcareous Tubeworms. Sometimes further divided into worms with spiral tubes (Spirorbidae) and straight (Serpulidae). Produce white, calcareous tubes, often with longitudinal ridges, thickenings, spines. Shape, size of cover (operculum) often useful in determining species. Includes genera: Serpula, Spirobranchus, Protula
Enough of this taxonomic introduction. Did you already know this stuff about these critters? Onto the captive use info.
You want these spiffy worms in your marine system, reef? Sure you do. They're generally hardy, easy to keep, interesting and gorgeously beautiful! Besides, they're cheap (relatively for marine livestock) and maybe even free, gratis with "live rock". You can buy or possibly collect them yourself. These families are worldwide in shallow tropical to temperate seas. What to look for? First of all, vital signs! Are their crowns in evidence most of the time? Do they quickly respond to motion, shade, touch by complete retraction? For "leather" and sandy type tube worms is the tube complete? That is, is the base end closed, the outer margin clean and the body of the tube not torn? If possible get worms with a good portion of the rock, etc. they were attached to/with.
How do the other specimens offered appear? Both Serpulid and Sabellids bear a pair of large mucus-producing pads that rotate and lay down a mucous coating on the inner surface of the tube, building and re-building the upper lip much like a rope-pottery making technique in healthy specimens.
The general co-factor questions apply> What are they feeding? How often? How? What is the specific gravity of the system water the specimens are in? How long have they had them? Where are they from? Such worms hail from the Philippines, Hawaii, Mexico, Florida, California... I shy on the side of buying "newer" stock; to avoid the detrimental effects of probable starving since collection.
Tube and Fan worms do fine in high quality natural and synthetic water of low to medium organic load (aging), any given reasonable range of temperature. Higher salinities are appreciated as per most invertebrates kept.
Vigorous water movement is helpful for aeration, excretion, circulation of food items... Placing them in a couple of inches of fine silica or coral sand, or betwixt rock/coral rubble is generally acceptable.
Territoriality is a non-question as long as sufficient food, circulation and gaseous exchange is available.
Introduction/acclimation is similarly simple. If avoidable, do not lift specimens from the water into the air. The water supports their bodies and trapped gas can be a problem.
Predator/prey relations: some invertebrates and fishes can and may eat your worms. Wrasses, some basses, triggers, shrimps, crabs et al. will try out most anything as you know. Healthy worms are quick to pull back into their tubes, but... Oh and they themselves will greedily filter out any particle, plant, animal or mineral of appropriate size which brings us to
Foods & Feeding:
Daily to a few times weekly offering of live (brine shrimp nauplii, rotifers...) or prepared foods (store bought or home-made) is recommended. Clam "juice", other "meaty" foods frappe'ed in a blender or smooshed with spoons or other tools applied in the general area (with a syringe, turkey baster device...) with most all particulate filtration switched off for the duration (@ an hour?). Other times and places I've plugged appropriate set-ups for intended such systems, including the use of timers or temporary switches to cut down on fouling from feeding...
A very nice examination of the structure and behavior of feeding in these two families can be found in most invertebrate zoology texts. See Barnes below.
Those faithful readers of these wanna be formula survey pieces might have noticed an oversight re repro. Nay, twas intentional. These worms have bizarre and varied modes. As a boy in the P.I. I was familiar with a practice of collecting certain "native" marine foods with baskets, timing our efforts with the tides and lighting. Some time later, it's dawned on me we were collecting (and eating) epitokes of polychaete worms. Believe me, I'm not making this up; some species basically break in half, the rear portion forming it's own "head", swims off and reproduces in the upper water column.
Tubiculous or tube-bearing polychaete worms are common fixtures in most shallow water marine environments. They make for colorful, hardy captive material when selected and collected appropriately.
One word of caution re collecting your own. Avoid intertidal specimens. These generally fare poorly in constantly submersed conditions.
Marine Hitchhiker/Critter ID (Maughmer, Toonen, Tompkins)
Barnes, Robert D., 1974. Invertebrate Zoology. W. B. Saunders.
Kaufman, Les, 1973. Worms. Marine Aquarist 4 (4), 1973.
Maier, Robert von, 1991. Bristle Worms. Discover Diving. Sept./Oct. 1991
Mancini, Alessandro, 1990. Tropical Tubeworms in the Marine Aquarium. FAMA 8/90.
Schlais, James F., 1981. Bristle Power. FAMA 1/81.
Walls, Jerry G., 1980. Tubeworms. TFH 3/80
To: Errantiate (i.e. Non-tubiculous) Polychaetes (many known to hobbyists as "Bristleworms"