My oddballs - Terrestrial nemerteans and flatworms

[Umbra]

Just spotted 2 more egg sacs, they seem to like to lay them inside the driftwood so getting a picture of them is quite difficult. This is the best I could get without removing the entire lid which I don't like to do because of humidity fluctuations.

 

[Tleilaxu]

Please make videos of your land "worms" hunting down and eating the spiders.

 

[Umbra]

I only feed yellow sac spiders to the Rhynchodemus sylvaticus and only if I find them in the house during winter. Yellow sac spiders are introduced here and are considered by many (including other members of my household) to be a pest so I have no qualms using them as feeders, but I wouldn't take one from outside and use it as a feeder if I have regular feeders on hand. My R. sylvaticus generally get Drosophila and small crickets and I keep the tank stocked with springtails for the juveniles. I do have a few videos of the worms already on the prey but I'll try to get some of the capture as well.

 

[Scythemantis]

I love these, as you probably know. I have the same large Florida species, which actually arrived as a hitch-hiker in one of my tanks, and have a population that comes and goes seasonally in my whip spider's tank. They never seem to attack her, so she's just too large for them, but they clean up her spare crickets and especially love isopods as prey.

I also recently found the largest one I've ever seen growing fat and happy in my back-up isopod colony!

I have however never seen juveniles like you're showing, despite my colony going for years!

 

[Xafron]

So you're the one that posted photos of a worm eating a cricket. I briefly saw it a few days ago and went back to try and find it later so I could learn more. No luck.

I'm strange. I'd pick up a tarantula or scorpion before I touched something as mundane as an earthworm. Something about worms really unsettles me on a level few other living things do. That being said, this fascinates me.

 

[Xafron]

When I was a kid I remember finding a flatworm under a rock in my front yard. Just now googled it. Based on what I remember, it would have been a "hammerhead" flatworm. It was orange and/or yellow with at least one dark brown or black stripe down it's back, maybe a couple stripes. Again, was long enough ago that the details are fuzzy.

 

[Umbra]

@Scythemantis the species you have isn't the Geonemertes that I've been posting pics of, it's actually not a nemertean at all - you have the land planarian Caenoplana sp. Those reproduce via fragmentation which is why you never see juveniles!

@Xafron maggots en masse have the same effect on me, a few and it's just fine but if I see a corpse of some sort full of them....yikes.
Your orange flatworm sounds like Bipalium adventitium, a pretty neat little predator of earthworms.

 

[Umbra]

I managed to capture footage of Geonemertes pelaensis feeding! I apologize for the quality and the vertical orientation, G. pelaensis is negatively phototactic and I didn't want to scare it with direct light. Given the location of the worm in the tank at the time it was easier to capture with a vertical orientation than a horizontal. If I had a second set of hands I could have gotten a better video - hopefully next time I can get a better video.

You can see the proboscis fire out, which ensnares and then injects the cricket with a toxic cocktail via a small stylet. The proboscis is extremely sticky and the venom is fast acting, once captured prey is almost immediately subdued.

I will try to get video footage of Rhynchodemus sylvaticus next!

 

[Tleilaxu]

So what's left when they eat? Amazing video. Hopefully you will be able to record the whole process of hunting to feeding close up.

Now excuse me while I watch it again.... And again....

 

[Umbra]

It's been a while since I've updated this thread, but I have since let the Geonemertes viv grow wild. I have a ton of hatchlings and juveniles of different sizes and I want to disturb them as little as possible. I will be setting up a larger enclosure for another culture of these ribbon worms as the juveniles get a bit larger - they seem very delicate at small sizes.

 

[arachnoherp]

Hey! Im not the only person that keeps predatory land ( and soon aquatic) planaria!

 

[LawnShrimp]

It's like a jungle in there! Nice setup for the little squirmies!

What sort of care is needed for the South American Geoplanidae? I was thinking of obtaining a few of the vibrantly colored species. Do they need a fresh supply of earthworms and snails (I can easily breed leatherleaf slugs and Cepaea) and are they illegal?

 

[Salmonsaladsandwich]

Sometimes at night I see small, very thin black or brown worms up to around 1 inch with tapered heads sticking to the sides of buildings. They're probably flatworms of some sort but I suppose they could be nemerteans. Do they sound familiar? I might be able to take pics of them the next time I see them.

I also see Bipalium adventitium pretty often. A little while back I found a wild one out and about and put an earthworm in front of it, which it promptly wrapped itself around and devoured.

 

[Umbra]

It's like a jungle in there! Nice setup for the little squirmies!

What sort of care is needed for the South American Geoplanidae? I was thinking of obtaining a few of the vibrantly colored species. Do they need a fresh supply of earthworms and snails (I can easily breed leatherleaf slugs and Cepaea) and are they illegal?

Depends on the species. Many Geoplanidae are consumers of gastropods or small arthropods (millipedes and isopods especially) so make sure you figure out what they consume. They can take a few days to weeks to get adjusted enough to accept prey so be patient and offer a wide variety of prey items until you figure out what they like to eat!

Sometimes at night I see small, very thin black or brown worms up to around 1 inch with tapered heads sticking to the sides of buildings. They're probably flatworms of some sort but I suppose they could be nemerteans. Do they sound familiar? I might be able to take pics of them the next time I see them.

I also see Bipalium adventitium pretty often. A little while back I found a wild one out and about and put an earthworm in front of it, which it promptly wrapped itself around and devoured.

The small worms you're seeing with the pointy heads are almost definitely flatworms, to go any further with identification I'd need to know where you're located.

 

[schmiggle]

Since when does MA have wild terrestrial flatworms!? I thought all the species were limited to tropics and subtropics.

 

[LawnShrimp]

I find the species Bipalium pennsylvanicum often around where I live, and recently found a bright orange one under a log. B. penn. can get as big as kewense. Flatworms are just more common, active, and colorful in the tropics.

 

[Umbra]

I'm finally going to revive this thread as I do have some updates. I'm now attempting to culture them in 32 oz deli containers and so far so good - I have a couple egg sacs in one of them. I have several others set up with springtails and dwarf white isopods established in each one. I plan on introducing a few adults to each container and removing them once they lay eggs. At that point, hopefully the young will develop, hatch and have a ready supply of food for the first few weeks of their lives until they get large enough to take crickets. I have observed some scavenging behavior from the adults where one worm will kill a cricket and other worms will slowly congregate and feed.

I have also managed to capture a slightly better video of them feeding - I hope to get a really good video when I set up my next 2 vivariums, one of which I'll showcase in a build thread.

 

[MoranDisciple]

Wow! Never even heard of owning these before but now I really want some. I live in PA so the only ones I have access to are the hammerhead obligate earthworm predators.

 

[mantisfan101]

Awesome specimens, if only I weren’t so afraid of them...

 

[Umbra]

Wow! Never even heard of owning these before but now I really want some. I live in PA so the only ones I have access to are the hammerhead obligate earthworm predators.

Bipalium sp. are interesting captives as well, give them a shot! I've kept one for a bit while I was in Japan, was awesome to watch it eat earthworms. Just make sure to change the substrate after each feeding - paper towel and moss substrate make this a lot easier as they produce a LOT of mucus.

You might also have Rhynchodemus sylvaticus, a small arthropod specialist that I posted earlier in the thread and Microplana terrestris, a generalist predator/scavenger of isopods, millipedes, snails, etc.

Go explore local forests after a period of rain, I find lots on the lower parts of tree trunks - they seem to like to hide under the bark of the conifers here.