Pests

Oenone Fulgida - A predatory worm

melev — Sun, 17 Oct 2021 18:59:18 +0000

Oenone Fulgida - A predatory worm

You don't want this baddie in your reef

melev Sun, 10/17/2021 - 21:59

In 2008, during a late night flashlight reef expedition, I discovered something new and somewhat alarming. When the light shone on the critter in question, it could be described as a bright orange worm. As soon as the worm sensed the light, it retracted with lightning speed deep into the rockwork's crevices, completely out of sight.

Unsure of its identification, it is still a pest that needs to be removed from the reef aquarium. By relating my experience, I hope to help you learn what it looks like, how it acts, and how to remove it. Here is my story:

When adding new snails to my reef, it is easier for me to put a bunch of them in a jar and place the jar on the substrate. That night, the snails will emerge, using the jar's surfaces as a purchase for their feet. Climbing out, they quickly spread into the reef. While checking on them well after lights out, that is when I saw this bright orange worm stretching fully into the jar from its hold in the rockwork. It was probably 4" or more into the jar, and about 1/8" thick. The unfortunate few snails that were still in the jar were already long gone.

This worm exudes a type of toxic paralyzing ooze both for attack and defense. As it spreads this ooze ahead of itself, it stuns or kills its quarry, which it can then eat. This same ooze doesn't dissolve in the flow, but gives the worm a slippery cocoon to retract within as it snaps back into the rockwork. This is no Peanut Worm; it moves much faster when spooked.

Now that I saw the worm as well as its response time, I had come up with a way to remove it. Additionally, whenever we find a pest, odds are there are more of the same lurking in the system. Carefully studying the rock and substrate, I discovered a few of these worms. I know for a fact that they will eat astrea snails as well as small T. maxima clams. They may even eat LPS polyps, although I've not actually caught them in the process - that's just a theory on my part at the moment (this article will be updated as more information is collected). In a tank with no snails or molluscs, they can survive on other food and even detritus. In other words, they can live in the system and become an obvious predator later when the conditions are target-rich.

What has worked best is to turn off all the flow in the tank first. In this way, I can look down through the surface of my dark reef now that the ripples are gone. Carefully shining the flashlight beam at a nearby area, I make it a point not to let the light cast on the worm directly. Under the dim lighting, the worm doesn't feel threatened and continues to go about its business. Using some 8" forceps (giant stainless steel tweezers from many online vendors), I carefully lowered them down until the two tines are broaching the worm. Keeping your hand steady is key. Quickly squeeze the forceps together and don't let go. The worm will try to retract as soon as it senses contact. While grasping the forceps, pull the worm steadily from its hole. The slime works in your favor in this case, as the worm has no traction and slides out completely. The worm may stretch out to 14" or more during your tug-of-war (okay, that's an exaggeration but you did tug it out, right?) but its normal shape seems to be around 8" - 9". The pinched area may bleed. If you pull too hard, you'll break off a segment. Ideally, break off the head so it can't survive; tails can heal and regrow. It is possible to miss since the worm is quick and your forceps may snag on small bits of substrate or rock, leaving just enough gap for the worm to slip through and away. Check back 30 minutes later or the next night and you may find it in the same general area.

Oenone fulgida seems unaffected to be out in the air rather than water

Oenone fulgida's slime appears to be a toxin or paralytic to its prey

Oenone fulgida's slime can be a path for the worm to travel through

It's a creepy creature, and looks a little like an aquatic millipede. The first one I captured was put in a Salifert test beaker for observation and pictures. Surprisingly, the worm emerged from the water and was willing to crawl out and across my counter top. I spent some time observing it, and noted it has a ton of legs for locomotion, unlike the cilia that we see on Bristleworms. The head has two eye dots and a snout that looks like a platypus bill. As it stretched out of the water, the ooze it created was readily visible. I believe the gel is what allows this worm to exist out of water, as it can travel within it. Each time the worm pulls together tightly, that's when more of the gel-like substance appears. You can see it in the slideshow below. Check out the specimen working across the sink's drain!

I never touched this worm, nor did I smell it or taste its ooze. My assumption that it is toxic is based upon the fact that the snails didn't try to escape their untimely end. They were either smothered or paralyzed in place, which allowed the worm to eat them.

Each night, I'd carefully study the rock for any signs of the bright orange worm. Since they are nocturnal, that's the time they are active. If I saw a hint of orange, I'd focus my attention in the surrounding area for further sightings since they tend to be 8" or longer. That doesn't mean they can't start off smaller, it just means I never saw any until they were quite large. I removed at least six from my system over a six month period. You may discover a strange sandy-tube on the sandbed moving in the flow, that was my clue that the worm had been there and had used it as a source of travel to its destination. They were discovered both in my 280g reef, my 20g angled tank, but not in my sump or suncoral tank. I did find two on the kitchen tile, dried up and dead. I'm not sure how they ended up down there, unless they were clinging to my canopy when I removed it and placed it on the floor. I saw one retract into a small rock covered with zoanthids, which I pulled out of my tank. I chipped away rock from the underside until I could snag it with the forceps to tug it out. I used toothpicks to block alternate exits so it would have no other choices. I was determined to remove it.

If you are losing clams or a lot of snails - more than you can credit to aggressive hermits - you too may have one ore more of these worms. Don't panic or rip your reef apart in search of these worms, just start hunting them down and extracting them. That's what I opted to do and will continue to do if I encounter more in the future. They are kind of neat to observe and I suppose someone out there would be happy to keep one in a species-only tank, feeding it snails on a weekly basis.

So what is it? I've contacted three difference sources and here are some of the guesses.

Genus: Oenonidae or Halla
Family: Glycerid or Phyllodocid
Species: Oenone fulgida

The only way to know for sure is to capture one and ship it to a worm expert. But I'm pretty certain I have the right identification in this blog.

Reef Blog

That's surprising...

melev — Sat, 13 Jan 2018 18:42:32 +0000

That's surprising... melev Sat, 01/13/2018 - 21:42

Sometimes we may notice tiny pockets of air building up in the area where the sand touches the glass. Occasionally you'll see worms, or pods, or just an empty tiny cavern to peer at, but this time I saw something different. This is a typical view, captured with my iPhone:

But now that it caught my eye, I bent closer to get a good look. And I discovered valonia growing under the sandbed. That's somewhat hilarious to me. Spock loves eating it, so now I want to say she's hoarding it like a hamster in her bedding. hahaha I'll have to unearth it so she can devour it.

Never seen anything like it. Have you?

Reef Blog

A pest I've not seen in a long time: red bugs

melev — Wed, 10 Jan 2018 23:32:58 +0000

A pest I've not seen in a long time: red bugs melev Thu, 01/11/2018 - 02:32

While taking a picture of the blue tort acropora that was recently mounted to the aquascape, I spotted something on the coral that I didn't want to see. To know for sure, I took a few more pictures with a couple of different lenses, trying to capture the exact spot I'd seen the first time. It turned out to be real, I found two red bugs in my reef today.

I've not dealt with them since 2006 ( http://www.melevsreef.com/articles/red-bugs-no-more ), and my next thought was how far spread are these into my reef? I took pictures of a number of SPS, and studied each image carefully for any sign of them. The good news is, I only found those on the blue tort so far.

While my pictures of these aren't as good as a different photographer I admire, my images show their yellow bodies with the tell-tale red head area. Here are the other SPS I photographed. All of these appear to be clean.

A buddy contacted me saying he has some Interceptor on hand, which would be the simplest solution. I do have a pair of Yellow Coris wrasses in my reef and now that the blue tort is affixed out in the open rather than hidden in a hole in the rockwork, they should be able to get to any and devour them. The question is just how many are in my corals? Just the two I found, or are there more?

Reef Blog

Wed, 02/07/2007 - 03:06

melev — Mon, 05 Feb 2007 23:06:00 +0000

Wed, 02/07/2007 - 03:06 melev Tue, 02/06/2007 - 02:06

A few things have occurred in the past few weeks while the Blogger software wasn't working properly. Now that it seems to be working again, here's the recap:

On Jan 18, we had a real day of snow here in Ft Worth. It was enough to put a 1" blanket of white stuff on my home and property, but it didn't last long. The city suffered from ice due to very cold nights, making driving hazardous. Many people didn't know how to deal with 'black ice' and over 200 wrecks were reported in one 24 hour period. My part of town was mentioned on the news repeatedly, encouraging people to avoid driving if possible.

On Jan 19, I removed a huge flatworm from one overflow of my tank.

It was shipped to a lab in California in case they could learn anything from it. It definitely was a mollusk eater.

On Jan 27, DFWMAS hosted Next Wave, and 103 people attended. We had an excellent time listening to the four speakers share their knowledge with us.

Extreme Corals set up a tank to display their livestock, including stuff from ORA.

Sandy Shoupe spoke about the tiny critters in our sandbeds.

One club member won this 75g RR tank.

Several sponsors sent goodies that were raffled off to the lucky ones.

I picked up three new corals that day.

And a few days later, I got one more coral.

On Jan 30th, I cleaned out and reset up the Calcium Reactor with new media.

On Jan 31st, I went crazy and took a ton of pictures. As this entry is getting pretty long, here is a link to the images in my thread on ReefCentral.com

Reef Blog

What's a whelk?

melev — Wed, 19 May 2004 18:33:00 +0000

What's a whelk? melev Wed, 05/19/2004 - 22:33

What is the difference between a Whelk and a Nassarius snail? Here's an image below. The creature on the left is a Nassarius, the one on the right is a whelk. Btw, whelks get much larger, while Nassarius don't.

If you look at the texture of their snouts, there is a specific pattern tatooed onto the flesh of the Whelk. Also, the whelk has a protective shell on its tail that it uses to seal itself in its shell when in danger. This gives it a water tight seal.

Whelks don't travel too quickly, ime. However, Nassarius glide across the sand very very quickly, moving on a large foot that allows it to move forward effortlessly.

Also, the feeler or eye stalks appear to be longer on the Nassarius snails, when you compare the Whelk's extended appendages.

Lastly, the shell. Of all the whelks I've caught, ever one of them looked like this one, with the darker coloration with whitish patches. In the past 48 hours, I've caught 7 total. They are all trapped in a box in the sump, awaying my decision. They can be super small or quite large, depending on age and growth.

Reef Blog

New zoas; hunting pests still

melev — Sun, 28 Dec 2003 21:42:00 +0000

New zoas; hunting pests still melev Mon, 12/29/2003 - 00:42

I added a few new zoos from a local reefer's tank last night. Most of the zoanthids haven't opened up yet, for various reasons. Mostly because my hermit crabs are checking out the new guys and that causes the polyps to remain closed. Some very light pink ones have fallen off their perch twice, so I couldn't get a good picture of those either.

These are the prettiest ones of the ones I got, and they were open today.

New Zoanthids. They are the size of a pencil eraser or smaller.

I'm still scouring the 55g for whelks, and found another nine last night. Look at how small they are. Newly captured. Even during the hunt, they were climbing right out of that cup!

A friend brought over two new corals. A Fungia baby that is about the size of a penny, and a Favite that wasn't doing well under his PC lighting. The Fungia (or Plate Coral) was fluffed up today, extending short feeder tentacles. The Favite (or Moon Coral) will have to adapt to the new conditions and hopefully grow healthy again. It has some recession in the tissue and the edges of the coral look lost, but the main section shows promise. My clean up crew should pick off all the bits of algae that are growing on the skeleton base where the tissue receeded.

Reef Blog

Is this Mithrax crab a problem or not?

melev — Fri, 26 Dec 2003 14:13:00 +0000

Is this Mithrax crab a problem or not? melev Fri, 12/26/2003 - 17:13

I was amazed that I caught this guy last night. I was about to do a coral dip to save the coral, and who happened to be hanging out on the backside? ;)

I put him in a small dish trying to decide whether to listen to the advice of those that opposed this pretty guy, and he hung on the edge of the dish for at least 15 minutes out of water.

Finally I dropped him into my refugium for now.

In a dish: Black Mithrax crab

Out of water:

In my refugium:

Note the shape of the claw in this pictures.

A crab in the hand is worth two in the reef?

In other news, the coral I dipped last night seems to be suffering from "brown jelly disease" and I was advised to dip it in Lugol's solution. (10 to 20 drops Lugols per Liter tank water; from 30 minutes to several hours). I pulled it out of the tank and put it in to a bowl, then using a turkey baster I endeavored to blast away the browned tissue. I expected it to come right off, exposing white skeleton, but it didn't come off. I left this coral in the dip for just over 2 hours, circulating the water with the turkey baster every 15 minutes. It is back in my tank now and I'm hoping it will recover. I did break off all the dead branches in this colony to improve circulation through the coral.

Reef Blog

Kalkwasser - be cautious even after rinsing area

melev — Sat, 22 Nov 2003 19:19:02 +0000

Kalkwasser - be cautious even after rinsing area melev Sat, 11/22/2003 - 22:19

Word to the wise: Be very careful with kalkwasser in your main tank. I mixed up a paste of pickling lime to kill one large aiptasia. I drew this mixture up into a syringe, pulled the rock out of the tank and proceeded to inject the vile beast until it resembled black tar. Then I rinsed the spot with another syringe of water.

What I didn't know is that the rock was very porous, and a lot of the kalkpaste was still contained within. After replacing the rock into its former position, the current blew the solution directly into the two gonioporas to the right of that rock. Both were badly burned, completely melting the tissue to the stony base in several spots. I was heartbroken, since these are very tough corals to care for in the first place.

Here is a picture of the purple goni before this occured. It doesn't look good and I have a feeling it won't recover. The green goni looks better, but you can tell it's missing quite a few polyps when it is fully extended.

Reef Blog

Those snails did what?

melev — Sun, 12 Oct 2003 19:45:12 +0000

Those snails did what? melev Sun, 10/12/2003 - 23:45

A very sad occurance.... I had a beautiful baby gold Maxima clam shipped to me from a friend in another state, which I carefully acclimated to my tank for a couple of hours. I placed this 1.5" clam on an empty shell in the center of the rockwork in my 55g under MH lighting.

I watched it closely for a few hours, until the lights went out. The next morning when I got up, I checked on the clam, and it was gone from its spot. I saw it on the DSB, covered with Whelks! I've seen these snails in my tank for over a year, and they never caused any trouble with a single thing, so I figured they were good as a part of the clean up crew. Apparently, their favorite meal is clam!!!!!! I quickly pulled the clam out, but it was way too late and only a strip of the mantle was left.

All the whelks I could find have been pulled out of the tank and put in a FO tank or the refugium. The worst part is that I was trusted with this clam, because the previous owner felt I'd take very good care of it. It is heartbreaking when things like this occur. :(

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