Interesting behaviours of Spatuloricaria

[Fallen_Leaves16]

Figured it was probably worthwhile to put some info down in a thread.

Most Spatuloricaria tend to prefer to lift or turn over objects with their mouth while foraging for food; oftentimes I'll see large caquetae "picking up" leaves (I imagine their papillose lips aid them in that endeavour) and setting them aside; they have the strength to move fairly heavy (80g+) rocks, too, though they mostly just shift those a bit. I do think that providing them the opportunity to browse about in this manner is a rather nice means of enrichment.
Their bite force is insane as well- I watched a particularly large female caquetae simply destroy a large ramshorn snail (albeit one with a somewhat thin shell) as if it were paper; I have no doubt that a bite from one would be capable of inflicting some damage on a fish, if they were ever inclined to hunt. Almost reminds me of Leporacanthicus, with the sharp, pronounced dentition.
I once found them completely devoid of colour; they were an awfully bright shade of semi-translucent white. Turns out the filters malfunctioned many hours prior, and I just didn't realize it. The fish were almost completely immobile, and only gradually regained their colour after two hours of the filters being replaced. I assume they're incredibly sensitive to hypoxic conditions, which does make sense, but the reaction to the conditions was rather unexpected.

I will try to get and/or upload pictures later.

[Kirin]

It is no doubt interesting from a behavioral aspect. These fishes are clear carnivores, morphologically and from the few ecological studies. Carnivorous species I've noticed generally have very mobile jaws but there are exceptions where jaws are reduced. There is a slight exception with some of the Peckoltia group but if they do in fact feed on seeds more there might be some shared morphology to manipulate them if you don't have the pharyngeal jaws to crunch them. From memory Lujan et al. (2011) hypothesized the jaw morphology of Spatuloricaria to be getting invertebrates out of small crevices. Which might well be the case but in stores they spend a lot of time on the substrate and are much more adapted at dealing with a substrate then Scobinancistrus, Leporacanthicus etc.
I think they are some what an intermediate as while dealing with the substrate but like Scobinancistrus they do have reasonably strong jaws so like you have noticed they are dealing with molluscs which is a tricky task. Fishes are usually either crushers or extractors for molluscs. Scobinancistrus and Leporacanthicus seem to be largely extractors. Loricariinae well depends on the taxa.
I would experiment with different snails though and keep an eye out for fragments. Malaysian trumpets and you'd be surprised.

[Fallen_Leaves16]

It is no doubt interesting from a behavioral aspect. These fishes are clear carnivores, morphologically and from the few ecological studies. Carnivorous species I've noticed generally have very mobile jaws but there are exceptions where jaws are reduced. There is a slight exception with some of the Peckoltia group but if they do in fact feed on seeds more there might be some shared morphology to manipulate them if you don't have the pharyngeal jaws to crunch them. From memory Lujan et al. (2011) hypothesized the jaw morphology of Spatuloricaria to be getting invertebrates out of small crevices. Which might well be the case but in stores they spend a lot of time on the substrate and are much more adapted at dealing with a substrate then Scobinancistrus, Leporacanthicus etc.
I think they are some what an intermediate as while dealing with the substrate but like Scobinancistrus they do have reasonably strong jaws so like you have noticed they are dealing with molluscs which is a tricky task. Fishes are usually either crushers or extractors for molluscs. Scobinancistrus and Leporacanthicus seem to be largely extractors. Loricariinae well depends on the taxa.
I would experiment with different snails though and keep an eye out for fragments. Malaysian trumpets and you'd be surprised.

Thanks! I probably should grab some Malaysian trumpets sometime.
My water's awfully soft, and snails typically do poorly; I think the ramshorn the Spatuloricaria crunched into pieces had a particularly brittle shell.
I would think that they inhabit rocky, fast-flowing streams with a predominantly sandy substrate in situ; Spatuloricaria caquetae do tend to mouth sand often and seem fairly adept at digging and shuffling sand around, in addition to moving around rocks and suchlike. Well, the adults do, at least; I actually don't think I remember seeing juveniles do that much at all. The moving rocks and digging thing, I mean.
They do have surprisingly mobile jaws. I even found a thread on PC some number of years old where a person claimed to have been bitten by a Spatuloricaria.

[Kirin]

If you're concerned about the water hardness many Ampullariidae, apple snails are found in softer waters, they seem to be much more omnivorous so maybe are one of the many who get their calcium more from their diet.
Maybe there is an ontogenetic change in their diets, it's never been studied in Loricariidae but for many I can't see reasons for it as they aren't that gape limited.
Catfishes can be such angry fishes it seems so wouldn't be surprised if one could bite it wouldn't. I've only had mostly scratches from Loricariids but have had cuts from Aspredinid pectoral fins.

[Jools]

Are there many gut analysis papers for this genus? I wonder what they are digging into in the wild. I figured larger insect larvae, but it could be snails or as wild as crustaceans. Do you think they are finding food in the substrate or in the "nooks and crannies" of a hardscape?

My only experience of these in nature is

Spatuloricaria tiura

in the Xingu. They were on leaf litter in about 2m of water, I didn't see them feed.

@corywally has bred these, I wonder what he thinks.

Cheers,

Jools

[CoryWally]

Hi, yes I bred Spatuloricaria cf. puganensis a few times, around 5-7 years ago and raised dozens of youngsters to adulthood. They were never particularly fussy about their preferred food, although daphnia and live worms (bloodworm and blackworm) were well received. If I recall, their first spawning was shortly after a live-food feed. There are write-ups in the Catfish Study Group Journal which are free to view on the website catfishstudygroup.org.

Cheers,
Mark.

[Fallen_Leaves16]

I don't think there's any studies on gut analysis of Spatuloricaria (or many studies on Spatuloricaria at all) out there at the moment. Hopefully that'll change sometime, though given how some species seem somewhat difficult to collect, it seems mildly doubtful. There are mentions of them being "known insectivores", and consumers of macroinvertebrates, so there's that, at least.
My Spatuloricaria (tuira, caquetae) do not venture onto the hardscape (several smooth, flat rocks, large pieces of bark), and in fact appear to stay as far away from it as possible, sticking to open ground with the rocks and some sand.
I recently added a bunch of random rocks from a local creek, of various size and texture.
They have been overturning the rocks and exploring the various crevices between them with their mouths. Very interesting behaviour; I regret not providing a varied substrate sooner.
I partially buried some bloodworm cubes, and stacked rocks around them to watch them forage; a large caquetae decided to dig its way to the cubes by digging under and around the largest rock. They are very skillfull manipulators of sand and small rocks; the way they roll large pebbles and use their mouth to dig makes the rearranging behaviour of many cichlids seem crude in comparison.
I have not seen the tuira interact much with leaf litter, interestingly enough. They seem far more comfortable searching between small rocks and sifting through sand.
Both are very aggressive with how they attack food, particularly the tuira. As soon as they detect a nearby food item, they rapidly pounce on it and seize it with their mouths.
I tried feeding more ramshorns to them. Turns out they're much more inclined to try and pull large snails from their shell than trying to crush them first; they still seem to try and break the shell via brute force with smaller snails, though. For larger snails, they immediately flip it so the opening points upwards, and gnaw at the opening, simultaneously chipping off small pieces of the edge, in an attempt to get at the meat. Once they snag the edge of the operculum with their teeth, they try to pull and pry the snail out. They're not particularly good at it, and typically give up after a few minutes (if they try mouthing it for more than a few seconds), but it does seem to work every now and then. I don't think the majority of their diet revolves around mollusc flesh; the way they hunt seems too much unlike what I would expect from a snail eater.

Hi, yes I bred Spatuloricaria cf. puganensis a few times, around 5-7 years ago and raised dozens of youngsters to adulthood. They were never particularly fussy about their preferred food, although daphnia and live worms (bloodworm and blackworm) were well received. If I recall, their first spawning was shortly after a live-food feed. There are write-ups in the Catfish Study Group Journal which are free to view on the website catfishstudygroup.org.

Cheers,
Mark.

Can't believe I forgot I read your articles on C. puganensis some years ago; it completely slipped my mind. They were rather nice write-ups; very informative. Makes me want to try my hand at spawning S. caquetae someday. You mentioned MTS disappearing from your Spatuloricaria tank- did you see any empty shells or shell fragments?

[Kirin]

Are there many gut analysis papers for this genus? I wonder what they are digging into in the wild. I figured larger insect larvae, but it could be snails or as wild as crustaceans. Do you think they are finding food in the substrate or in the "nooks and crannies" of a hardscape?

My only experience of these in nature is

Spatuloricaria tiura

in the Xingu. They were on leaf litter in about 2m of water, I didn't see them feed.

@corywally has bred these, I wonder what he thinks.

Cheers,

Jools

As far as I know I've not seen one but I can double check but it doesn't seem so. The theory in Lujan et al. (2011) is extracting food from crevices. Their morphology is convergent to Scobinancistrus and Leporacanthicus who are definitely prizing their food from something. I do find it a bit odd their head and jaw shape is so vastly different from those who do interact more closely with the substrate e.g. Pseudohemiodon, Loricaria.