Lophiosilurus Alexandri Spawning!

[yellowcat]

Where to start, well first a backstory, I bought a pair around 16 months ago @ 3 1/2" & 4", Since then they have grown to 11" and 12" TL. Up until now they shared my 130G tank with my Auchenoglanis Occidentalis- Volta River strain giraffe catfish, originally @ 10" now about 15" TL male fish. Until a couple of weeks ago no issues whatsoever complete harmony. Normal behavior for the "pacman" cats is they stay buried in the gravel, rarely emerge with only clue being a pair of lips level with the gravel to catch guppies presumably. Otherwise only feeding when food items touch their exposed lips like worms and slices of tilapia. Recently they have suddenly become more active than usual, out and about as it were. For some reason the giraffe cat began showing interest in the larger one, nipping at it's tail! At first I wondered why? I should mention that gender identification in these fish cannot be determined by external examination and that they become sexually mature after one year of age. Anyway I have been looking for any clues as to spawning behavior from what little to be found on the subject. In any case I surmised that perhaps some hormonal change in the female, like excretion of spawning pheromones may have been responsible for the G cats response? In any case I couldn't tolerate the tail nipping and removed the G cat to a 40G tank with my B. Villosus, neither are happy about it but no aggression, likely will have to sell the G cat even though a fave fish. A good point for a photo or 2:

As a result if the large fish reaching the 12" mark, I got in touch with the source of my fish and sent the photo above and we both agreed that just from general appearance they look to be a M & F pair. He mentioned that a friend that bought 4 of them had recently noticed "trenching' behavior with his fish, mine have done the same, digging long trenches in the gravel. Days later my fish have been extremely active with voracious appetites taking many nightcrawler worms and filet d'tilapia and a finger or two, at the tank's surface! Another clue may be the ventral area gold pigmentation which is new... OK just reached maximum photo space allowed so will be going to part 2 of this post...

[yellowcat]

Where was I, OK here's a photo of the females belly showing the pigmentation, the male too:

I should mention another behavior, last week the male fish was also nipping at the female's caudal penduncle causing some shredding, now stopped and healing after adding a bit of Melafix:

Last night, signs of the male preparing a nests this photo suggests:

This morning further evidence:

Since this last photo the male seems to have taken over the nest right now, many subtle things occurring, too difficult to describe at the moment, etc. This species have been known to spawn in home aquaria a time or two in the past, I've noted. Since this species has been unavailable for decades until recently, there's little if any, anecdotal information to be found about their spawning behavior in the wild or in captive settings. Much scientific literature exists about induced spawning under laboratory conditions, very involved, complex and admittedly beyond my capability to glean much from it, lacking the vocabulary required, etc. Yeah I'm fresh out of carp pituitary gland extract to further induce their mating instincts and such! At least from much research, I at least know what to look for as far as the male guarding and fanning eggs and to look for an orange sticky cluster of eggs deposited in the nest. For now the male is laying in the nest, the female resting nearby. I have never tried to breed any fish other than guppies, that do it whether you want them too or not. Many on this site regularly breed many, many species of catfish and from reading about everything to encourage spawning such as manipulation of day length, water changes, temperature adjustment, PH changes, bedding substrate, caves, adding extracts, etc. All I can provide is PH around 6.5 and temp of about maybe 77 degrees F. Anyhow, exciting to witness their behaviors, should things progress beyond what's happening so far today, at the very least I would remove all the guppies in the tank just in case there could be fry, but with no expectations at all, happy to share with those with more knowledge than I on the subject. It just occurred to me that so many creatures on this planet have what's called the 'biological clock' and presumably a biological calendar as well, which makes me wonder if that applies to species from the Southern Hemisphere? Well after all, it is Springtime in Brazil!

[bekateen]

Hi Yellowcat,

This is incredible! Congratulations! I hope you get eggs and fry!

This makes me think of my Pseudopimelodus. I have 1/3 of their tank with a false floor with numerous spawning mops. I've worried that they might be a sand bed spawner. Currently the other 2/3 of their tank is bare bottom with cobblestones. Maybe I need some sand.
Cheers,
Eric

[yellowcat]

Hi Eric, well congratulations may be a bit premature, not ready to hand out cigars just yet! As of this morning both fish have sort of abandoned the nest area for now, just going their separate ways as before. Maybe it's just a trial run for them as one may not be ready. I would think there would be signs with the female's anatomy to show she is gravid, like a swollen belly part to reveal the development of egg sacs ? Again I don't know with this species what to look for. For now at least I've been able to document some things with photos to show their attempted progress with their spawning ritual behavior. Likely no need to set up a nursery tank for now! I shall report on further developments of interest should they occur... Cheers

[yellowcat]

For Eric, sorry, caught up in my own thing and failed to comment on your situation with the B. Villosus as I intended. Since both of us are in uncharted territory with insufficient data available to predict spawning behavior with either species, the need to experiment is surely worthwhile. I suppose the introduction of mops and such is on the assumption that the species in question lays eggs on plants, wood or rocks in the wild as many species do. If not, then one could assume that they are more likely to build nests in sand or gravel as many catfish do. Were that the case and as a practical matter, I would think that perhaps a fine gravel bedding substrate might be preferable to sand if the species lays a cluster of sticky eggs, as gravel could provide better adhesion and better water flow with any existing tank current or from the male fanning the eggs. If nothing else, sand or gravel, giving the fish another choice, couldn't hurt, eh?

[Viktor Jarikov]

Nice writeup and story, Kirk, good job! I am happy for you. Did I miss it or you didn't say which one was the supposed male and female of the two? As for the gcat, I wonder if the pacmans' sudden frequent appearance outside of the gravel triggered the gcat because they can be territorial.

[yellowcat]

Thanks Viktor! I didn't say but the large one is the female. Once the giraffe cat was removed, I sensed that the pacman cats felt more at ease, free to move about as they please. I don't think the pacman's recent emergence triggered the giraffe cat as there have been periods in the last year when they would become active for a few hours or days at a time and no response from the G cat before, other than competing for food in the evening as he likes nightcrawlers and tilapia too. Mr. Volta hasn't otherwise shown much in any way of territorial aggression but since he and his 2 tank mates are still growing, perhaps he may start to feel that tank is becoming too crowded for his liking? I try at times to think like a fish but not very good at it sometimes! If the spawning thing doesn't work out, I may try to re-introduce the giraffe one back into the tank and see how it goes as I really do like him as a pet. As usual, it takes over a year at times for most giraffe cat species to lose their fear and shyness, he's now very personable I must say, we'll see. I don't want to sell him but will if he gives me no choice, I reckon..

[yellowcat]

Update today. More suspicious activity the last 2 days. At one point it seemed they had lost interest but late yesterday the size and depth of the potential nest was enlarged by the male fish. As to Viktor's previous question, I'm assuming the smaller fish is male, it has been the smallest over time, never surpassed the growth of the other. Due to nest preparation activity and nipping the tail of the large one which is common with many species, not to mention overall subtle differences in morphology now that they are larger, hence the conclusion. This morning I observed the female laying directly on top of the male and making a wiggling motion I've never seen before. They commonly will lay on top of one another, seemingly 'cuddling', stacking or what you want to call what these fish often do. This was different. Surely some form of pre-spawn behavior to my mind anyway. It would be nice to have 24 hour video monitoring and a qualified lab assistant to interpret things but it's just a living room aquarium, me and my cat. Watch this space, just in case, eh

[bekateen]

Santa might not be dropping presents, but hopefully your fish do!

Good luck!
Eric

[yellowcat]

Update, well it didn't happen beyond the behaviors that ensued for a few weeks, mostly nest building, excavation at one end of the tank and both spending time there, then doing the same at the other end of the tank. I was looking for any evidence of a gravid female (assuming the larger fish is female) but no sighting of any unusual bulges to indicate egg production. Here's a nest pic:

After spending time in or near the nest's for a few weeks, it seems they have lost interest and have resumed normal past behaviors, laying atop one another or locating apart in various spots and only partially burying up in the gravel rather than fully so as when they shared the tank with the giraffe cat.
What has been most remarkable is their aggressive to actually violent breeding behavior during the last few months! Now when opening the tank lid they rise up from the gravel to skimming the surface waiting to be fed, when offering strips of tilapia fillet they will rip them from my fingers with violent snaps of their jaws sucking in huge gulps of air in the process, even sticking their head above the water to get their food! I only feed them every other night when they both will consume a whole 6" tilapia fillet between them and still want more. They also will eat frozen silverside minnows, other cut fish and nightcrawlers of course but quit feeding them as those big earthworms are now around $10 a dozen and wouldn't last for a single feeding anymore.
Their growth rate has increased dramatically since I started this post last December when they were @ 12" long, now they have grown to 14" and 15" respectively!
I wish it weren't so as I'd hoped to keep them for longer but at this rate of growth I'll have to consider selling them in the next few months I'm afraid.
Some observations with the species, first they seem to have poor eyesight or rather seem to be nearsighted but with small eyes facing upward limits their perspective. They will react to food presented above them whilst on the bottom but don't react much visually in other ways. Also unlike many other catfish, they are less responsive to finding food items by sense of smell in the water or by coming in contact with their skin or fins. If they strike at a slice of fish and miss it, they won't go back down to the bottom to find it, preferring to wait for more from above. Of course if I leave the food on the gravel they will eat it if they happen to run into it but don't actively search for it.
When they were juveniles I had to feed them with a pvc feeding tube and placing the food within an inch or two of their face or they would ignore my offerings.
I have kept many dozens of catfish species for decades but this species is the most unusual and unique of all of them, not only in appearance but behaviors that range from one extreme to the other, amazing fish overall!
Among the may photos I've taken of these fish I also have many videos of their feeding sessions, with posting some in mind, but I being tech-challenged and new to editing an/or posting videos online, workin on making that happen...

Wide bodies...

Best Friends:

All for now...

[Viktor Jarikov]

Awesome stuff, Kirk, as always. Thank you!

[bekateen]

Spectacular!

Cheers,
Eric

[Koltsix]

Hi Yellowcat, awesome to read your updates. Been awhile since you and I have spoken about our Pacmans. The potential possibility of them spawning for you is awesome. I look forward to hearing updates.

It's also nice to see yours have assumed behavior similar to mine. With the exception of breeding behavior and some other minor differences. Mine for a long time now have shown begging behavior and like yours snap at the surface in anticipation breaking the surface. Greedily snatching anything offered. They still take readily eat Kens meat wafers as well as shrimp stuffed with pellets and nightcrawlers. Mine however will actively seek out food that has bypassed them that falls to the bottom. They do prioritize food falling from overhead but when I stop, they will actively search the bottom. Mine do seem to have a good sense of smell and touch though. Opening the hood doesn't cause any reaction it starts immediately after food introduction. I first throw in floating pellets for my Ompok and Ossubtus Xinguensis which instantly cause them to stir and shoot to the surface and they actively find the floating food.

Thank you for the great info and observations.

[yellowcat]

Hi Koltsix, thanks for your comments and observations as well, good to compare notes about keeping these fish with so few in captivity. Nice that your fish show similar feeding behaviors to mine. I got in touch with the vendor where I got them when mine started showing possible pre-spawn behavior and he said a friend has 4 of them and they were moving gravel around in an unusual fashion around the same time, so maybe a seasonal thing? Perhaps differences in their feeding and/or breeding behavior is influenced by the existence of other tank mates or in my case the lack of same other than a few dozen nervous guppies. Things did change after they had the tank to themselves. One other observation is their ability to sense time, I feed all my catfish around 10PM every other night. On non feeding nights these fish stay relatively inactive but if it's a feeding night, around 10 o'clock
they become active and start moving around in anticipation somehow knowing what's up. That they might adjust to a daily/nightly routine as do cats & dogs is one thing but that they can sense and anticipate their off night feeding time is remarkable, if that's what's going on...
from last night, dem belly full