PlanetCatfish.com

EDIT: I finally got my first spawn. More information HERE.

Today I obtained from my LFS a group of 6 adult or subadult Microglanis, the kind usually sold as . Looking at colors, I see lots of individual variation. It's difficult for me to imagine that a little fish like this, spread out so widely across Venezuela and Colombia and even into Peru and Brazil, is "all one species." There are no similar described Microglanis from the immediate area, so my thoughts fall to undescribed cryptic species of similar coloration. I tried to get good pics of the pectoral spines today and overall wasn't very successful.

Here are 3 of the 6 fish. Each has a different color pattern on the tail. All of these patterns can be found on the CLOG page of C. iheringi, but of course, that would depend on those fish having been ID'd correctly to start with. And if there are cryptic species, then who knows what people have been sold in the past.

For two of the fish, I've typed characters which I think represent the color pattern, a 3 and a B with the hollows filled in. The 3 pattern was in the original description of M. iheringi. The other three fish which I received but I don't show here all have the "3" pattern on their tails.

Other variations in color pattern are:

• On the dark fishes, the brown/black color band on the caudal peduncle arcs forward and merges with the brown/black saddle below the adipose fin; but on the pale fishes, the two dark bands are clearly separate.
• On the two pale fishes, looking at the dark saddles under the dorsal fin, their anterior margin travels postero-ventrally, whereas in all my other fish, the anterior margine travels almost a direct vertical path.
• There are also dramatic differences in the coloration of the pectoral. pelvic and anal fins as well. The dark fish has bold flecked bands of color on the pectorals and anal, and some flecks on the pelvics, whereas the two pale fish shown here have either no color at all or very sparse, faint flecks in no organized line on these fins.
• The other thing which is odd is the dark base color on the smallest fish. I had read that the fish get darker with age, but my darkest fish are my smallest fish. Personally, I prefer the darker base color. Up close it reminds me of a fine horizontal wood grain.

Although there seems to be differences in caudal fin contour (more-or-less forked, with most-forked in the dark fish), one feature they all have in common is a smaller upper lobe of the caudal fin, with about 9‐10 rays in the upper lobe and 11 or more in the lower lobe.

Microglanis are certainly not "unspawned," but they aren't a commonly spawned fish, so I'm giving them a go.

Cheers, Eric

P.S., the photos are all magnified the same, so each fish is shown in proportionate scale. In all three photos, the field of view is 59 mm, from left to right.

Here's my best attempt so far at their pectoral spine serrations. Clearly the pics are insufficient. Ugh.

Cheers, Eric

Hard work these guys! At least to ID. Do you have any info on their place of origin to add into the mix?

Cheers,

Jools

Hi Jools, no not yet. My suspicion is these come out of either Colombia or Peru, but I can't rule out Brazil. I'll try to get info done the wholesaler. And, yes, I can tell this has been vexxing for a while: http://www.planetcatfish.com/forum/view ... 38&t=33984.

Cheers, Eric

So what the hobby has called M. iherengi for years is an incorrect id. This species is restricted to the Tuy and Valencia drainages of northern Venezuela. These are coastal drainages north of the Andes and it has been decades since any fish were exported from these areas. Several scientific names from these drainages have been incorrectly used in the hobby for a very long time because they were (correctly) applied in old aquarium books. When collecting shifted from Venezuela to Colombia, Brazil, and Peru hobbyists just continued using names like M. iherengi and Farlowella acus even though their fishes were from completely different areas.
I did once in Venezuela collect the actual M. iherengi in Venezuela but have no photos as my backpack was stolen while I was collecting in the creek. My car keys were in the backpack and so I ended up in a four hour stand off with the local villagers. Eventually my keys (but nothing else) were found and I was able to leave. However, during the stand off I had to let the fish go or they would have perished since I could not access anything in my car.
I think there is a good possibility that the coloration differences above could be related to sexual dimorphism.

-Shane

MODERATOR NOTE: More information about this collection trip is found here: Collection locations Microglanis iheringi

Hi Shane,

Thanks for the background. Your point about the type locality of M. iheringi is not lost on me; that's why I said it's difficult to imagine the species would be so widespread.

The other species which suffers from the "it's the only name we know" syndrome is , which has for decades been the go-to label for almost all unidentifiable Microglanis from Peru to Guyana to Amazonian Brazil and down to inland Argentina and Uruguay. But that species is a coastal Brazilian species, somewhat like M. iheringi is from coastal Venezuela.

In my opinion, more unsettling is not the mistaken use of M. iheringi by hobbyists, but the published papers by scientists who use Colombian specimens to clarify the description of M. iheringi. Also, well known scientists have identified museum specimens from Colombia and Peru and Brazil as M. iheringi. It seems pretty clear we need more or new type material for the original M. iheringi and genetically testable samples for someone to properly characterize the inland populations from the coastal M. iheringi.

As for your last point on sexual dimorphism, that would be great if it proves true. There are very few notations in the more recently described species (and none in the old descriptions) of male-female differences, other than girth and genital papilla shape. I don't recall color pattern being one, but it's not unusual in other species so ... yeah I'd like to confirm that if true. Relevant to this point, both male female Microglanis collected from the rio Uruguay in Argentina have the dark wood-grained complexion.

I've got the original and revised descriptions of all Microglanis except M. ater. I haven't finished going through them all, but I'm working on them to extract diagnostic features and color pattern info for the clogs. Wish me luck; I don't expect it's a small task. It's what stirred my interest in this group in the first place and led me to get some after all these years of seeing them in my LFS's and passing them over.

Cheers, Eric

"In my opinion, more unsettling is not the mistaken use of M. iheringi by hobbyists, but the published papers by scientists who use Colombian specimens to clarify the description of M. iheringi. <facepalm emoticon>."

Yeah, I'll keep to myself the number of scientists I have seen grab an old TFH book to make an identification... Online resources have probably all but stopped this practice, but in the field, an old book may be all that is at hand.

I kept the same, or a similar, sp in a group of six for several years. They were in a ten gallon tank with several inches of leaf litter (oak and maple) and a sponge filter. My hope was that some eggs might make it in such a set up. I hit them with rain water every few months but never found any fry or eggs. If I were to try again I would try a false floor or maybe an uplift tube in a small cave to a specimen container.

-Shane

Shane wrote: ↑27 Sep 2020, 19:24I kept the same, or a similar, sp in a group of six for several years. They were in a ten gallon tank with several inches of leaf litter (oak and maple) and a sponge filter. My hope was that some eggs might make it in such a set up. I hit them with rain water every few months but never found any fry or eggs. If I were to try again I would try a false floor or maybe an uplift tube in a small cave to a specimen container.

Thanks again Shane. My plan is similar. I plan to decorate their tank with oak and magnolia leaves, pinned under piles of Manzanita twigs, with a few tight clusters of small (1") flat cobblestones, all on a thin (1/4" or less) layer of pool filter sand as a base. Hopefully eggs and fry will be protected in the crevices between the stones.

First, though, I want to get the adults in better condition. IMHO, they look healthy now, but certainly not "fat and sassy."

Also, trying to arrange a trip later this week to the importer of these specimens, to find more individuals of the different color patterns, on the off-chance that I have two or even three spp. in this group of six.

Cheers, Eric

I went back to the source of my first six Microglanis and picked through the tank and selected 12 more. Some are big, over 50 mm SL! Some are dark and "wood-grained" (as I call the pattern) and some are bright yellow.

Also, the seller showed me the import sheet they came in from Colombia as ! Not ! Surprise?
One was very faded. Maybe same species??? Since there was only one pale fish, I saw no benefit to buying it, whether same species or not.

Also at least one I bought has a subcutaneous parasite. How do I treat this?

Thanks in advance,
Eric

It's likely everything in the catelog as M. iheringi is whatever you have and that the M. sp. 'venezuela' is M. i heringi. Just another one of those puzzles I had slated to have solved by the time I hit retirement.

Jools

My go to for parasite treatment of wild caught fishes has always been a formalin dip. However, I have no idea if it would impact a subcutaneous parasite. Maybe quarantine that animal separately and observe it.
-Shane

Jools,
I have two Venezuelan books with purported pictures of M. iherengi but have been hesitant to cite them as the books offer no specific collection location for the fish. That said, both photos show a darkly-colored pattern like the fish in the catelog as sp Venezuela.
-Shane

Shane wrote: ↑03 Oct 2020, 12:25My go to for parasite treatment of wild caught fishes has always been a formalin dip. However, I have no idea if it would impact a subcutaneous parasite. Maybe quarantine that animal separately and observe it.

They're in QT now.

I've seen something like this before in channel catfishes. If that case, the parasite used catfishes as one host in a two- host cycle: the catfish would have to be eaten by a bird or other predator for the parasite to complete its life cycle and reinfect other fishes. So if this is the same, leaving it alone won't harm the rest of the tank, but it won't help this fish.

Should I be concerned when medicating these fish that the bumblebees are smooth skinned fishes and not armored? Will they be more sensitive to meds?

Thanks, Eric

I'd bevery cerefull with medicating catfish. All of them.

Bas Pels wrote: ↑03 Oct 2020, 18:18I'd be very cerefull with medicating catfish. All of them.

With the possible exception of methylene blue (which I use rarely and only for fungusing eggs), I've found all the medications I mentioned above are very safe with all the corys and plecos I've ever kept. But until last week, I've never owned any , or any other soft-skinned catfishes. So they are a total unknown to me in terms of how sensitive they are to medications.

If the parasite is the kind I described, requiring two hosts to complete its life cycle, I'm inclined to leave it alone and just pray it doesn't kill the individual infected fish. If it can't spread to other fish, the rest of my group is fine. But if it is a different parasite which might spread within the tank to other fish, then I'd like to treat the tank.

Ironically, I saw one other specimen at the LFS that had the same infection and I intentionally left that fish at the store. But on this fish I bought, I didn't notice the parasite until after I got home.

Cheers, Eric

Love these mini cats. I have one in a 55g so I never get to see it.

I have used the formalin dip on, literally, thousands of wild caught fishes with no observed negative impact. Several people recommend dips as long as 30-60 minutes. I have found that even 5 minutes (with very sensitive fishes) is enough that you can watch external parasites drop from their host.
-Shane

Thanks Shane.

Cheers, Eric

Put together a video of all the fish on arrival.

Cheers, Eric

Microglanis poecilus? South American Bumblebee Catfish

EDIT: After reviewing the photos of the fish shown below, I measured the dimensions of the container in which they were photographed. I underestimated its size, which was in fact nearly 4" internally. Therefore I've edited the SL sizes mentioned below to reflect accurate size measurements. The fish were in face nearly twice as long as I'd originally written. The current SL values are the correct SL values.

Shane wrote: ↑27 Sep 2020, 14:12I think there is a good possibility that the coloration differences above could be related to sexual dimorphism.

-Shane

Hi Shane,

Following up on this, perhaps yes, but not what I was expecting. A few days ago I sorted my 18 specimens. Sadly, I found only 17, with one unaccounted for in the tank of 12. Maybe it's still in the tank; I don't know.

Of the 17, four are clearly of the dark wood-grained variety, with two showing obviously swollen abdomens so I suspect females (and the other two slender... so if males, then not sexual dimorphism unless we're proposing sneaker males). These fish are all about 40-47mm SL, with clearly bilobed tails, and they have a similar U-shaped brown saddle below the dorsal fin. [for reference, the container they are photographed in is 95mm across internally] Next, seven share the yellow body color or nearly so. These fish are longer, about 45-60+mm SL I estimate; the longest is at least 65mm SL. These fish have caudal fins which vary from emarginate to gently bilobed; and the brown mark below the dorsal fin is more of a ventroposterior slanting trapezoid, more narrow on the base with the posterior edge nearly vertical, than a U-shaped saddle. They also all share conspicuous yellow "teardrops" lateral to each eye. Although two are slightly more girthy than the rest, overall all are slender (either all males, or some females immature included). Finally, there were 6 which I could not sort easily. They are all small, about 45mm SL. Their caudal fin margins are bilobed, but to varying degrees, and their body colors are more-or-less dark yellow or wood-grained (one is yellow with bold brown spots - I imagine these spots more as blemishes on the yellow pattern rather than a unique color motif unto itself); finally, the brown area below the dorsal fin tends to be more the diagonal trapezoid than the U-shape. All of these are slender to slightly girthy; none are overtly rotund like the two small dark wood-grained fish.

Videos of all three groups are currently posted on Facebook. Later, I'll combine the videos and upload to YouTube for sharing here.

For now, I've sorted the seven yellow fish in one tank and combined the ten smaller fish in another. But if these are a single species, I would predict at this time that the males are long and yellow, and the females short and brown. I would not have expected the males to be so much larger than females.

This is so perplexing and intriguing to me. I need a student to help me run genetic tests on these to establish similarity and sexes. Or, the two extremes just need to breed without the other present. Ugh.

Cheers, Eric

P.S., side-note: All the fish, regardless of size or color or caudal fin shape, have a smaller upper caudal than lower, with about 7-8 soft rays above and 8-11 below (I'm vague here only because I don't know the convention for counting caudal fin rays ‐ at the upper and lower margins, when do you stop counting? Do you include or exclude the soft rays which terminate almost immediately? I think there are 7 dorsal principle rays and maybe 9 ventral principle rays).

Your observations and photos make the differences even more mysterious (as in more of a mystery) but are fantastic and add to our knowledge. Certainly another possibility is two very similar spp collected side by side. Farlowella mariaelenae and F. Vittata were imported in mixed batches for decades before the hobby figured out they were two different spp.
-Shane

Shane wrote: ↑23 Nov 2020, 11:57Your observations and photos make the differences even more mysterious (as in more of a mystery) but are fantastic and add to our knowledge.
-Shane

Thanks. Hopefully I'll be able to shine more light on this over time.

Shane wrote: ↑23 Nov 2020, 11:57Certainly another possibility is two very similar spp collected side by side. Farlowella mariaelenae and F. Vittata were imported in mixed batches for decades before the hobby figured out they were two different spp.

Ha! Apparently we haven't gotten much smarter. Three times in the last six months I've been in different LFS offering both F. vittata and F. mariaelenae comingled as common twig cats. Now that I know what to look for, I can't help but check every time I see them.

Cheers, Eric

Forgot to mention, one individual has an atypical caudal fin, which I would guess is a developmental aberration. This individual is smaller and darker, but clearly doesn't have the bilobed fin of the other small fish. It has the correct number of fin rays in the lower lobe, but too few fin rays in the upper lobe. Ugh, maybe all one variable species with a plastic tail?

Never mind, I'll stop going on till I have something of substance.

Cheers, Eric

Taxonomy update - there is no way my fish are . After studying the single photo we have on record and comparing it to the original illustration by Eigenmann, I've come to the conclusion that Microglanis poecilus must look more like than the fish I have or that we have on the CLOG for . Specifically, what I'm looking at on Eigenmann's illustration and the photo of M. poecilus is the brown saddle area under the dorsal. In both of these illustrations, as also seen in M. pataxo, there is a distinct and prominant pale yellow bar extending upward from below into the brown saddle area, essentially pointing antero-dorsally towards the base of the dorsal fin spine but not reaching the dorsal fin spine. This creates a brown arch effect on the fish's flank below the dorsal, and when viewed from above, this looks a bit like a large brown >< drawn longitudinally across the back, centered right at the base of the dorsal spine (which is further marked by a small pale spot). In all of my fish, and in the photos of M. iheringi here, the brown saddle area (regardless of shape) is a solid block of brown, with no intervening yellow uplift.

I've been staring at these drawings and photos for almost two months, and this huge difference only hit me now. As we say in one American TV commercial, "Wow, I coulda had a V-8!"

Cheers, Eric

Compare these photos:

• M. poecilus, dorsal view (Eigenmann, 1912)
  
• M. pataxo, dorsal view (Sarmento-Soares et al., 2006)
  
• M. poecilus, side view
  
• M. pataxo, side view (Sarmento-Soares et al., 2006)
  
• M. pataxo, side view
  

Off topic, (1) for lack of a better place to put it, and (2) because the value of this might be total mulm (substitute less polite word meaning similar material), below is a diagram which I've adapted from the Sarmento-Soares et al (2006) paper to imagine what might look like. I've been struggling to find a photo or illustration of M. ater (we have none, and the original description by Ahl (1936) lacked a picture). So I lifted one of the diagrams from the 2006 paper, modified certain body proportions to match those dimensions listed by Ahl and modified the color scheme to fit Ahl's description.

Ahl, 1936 wrote:Beschreibungen dreier neuer Welse aus Brasilien.
Von Ernst Ahl.
(Zoologisches Museum Berlin.)
Eingeg. 14. Juli 1936.

Die nachstehend als neu beschriebenen Welse befanden sieh unter Sendungen, die dem Zoologischen Museum Berlin von den Herren ARNOLD, Hamburg, und SCHOLZE und POETZSCHKE, Berlin, zur Bestimmung zugesandt worden sind. Ich möchte nicht versäumen, auch an dieser Stelle den genannten Herren für das schöne übersandte Material bestens zu danken.

Microgianis ater sp. nov.

Körperhöhe 32/3 mal in der Körperlänge, Kopflänge 31/2 mal. Kopf etwas breiter als lang, flach; Schnauze abgerundet; Auge 32/3 mal in der Schnauzenlänge, 71/2 mal in der Kopflänge, 31/2 mal in der Interorbitalbreite; Maxillarbartel so lang wie der Mentalbartel, nicht bis zum Anfang des Pectoralstachels reichend; Postmentalbartel noch kürzer; Maul breit, der Winkel vor dem Auge; beide Kiefer vorne gleich lang; vordere Nasenlöcher deutlich tubulär; Zahngruppen des Prämaxillare ohne rückwärts vorspringende Winkel. Dorsale I 6, ihr Abstand von der Schnauzenspitze 23/5 mal in der Körperlänge; der Stachel etwas über 1/2 der Kopflänge. Anale 14, abgerundet. Basis der Dorsalen, Analen und Fettflosse etwa gleich lang. Pectoralstachel stark, mit großen Zähnen entlang dem ganzen Rande an beiden Seiten, die der Innenseite bedeutend größer als die der Außenseite; die Zähne des äußeren Randes nach hinten, die des inneren Randes nach vorne gebogen. Ventralen direkt hinter dem letzten Strahl der Dorsalen, gerade den Anfang der Analen erreichend. Caudale nicht sehr tief gegabelt, der untere Lappen etwas größer und länger als der obere, etwas kürzer als der Kopf.

Grundfärbung (in Alkohol) schwarz, Bauch grauweiß; ein sehr undeutliches, eben nur angedeutetes, wenig helleres Band über den Nacken von Pectorale zu Pectorale, ein ebensolches, ebenfalls nur schwach angedeutetes Band hinter der Dorsalen; ein heller Fleck vor der Fettflosse in der Mitte des Rückens. Alle Flossen schwarz, die Dorsale mit einem weißen Fleck in ihrer Mitte nahe dem hinteren Rande, die Caudale mit breiter, weißer Querbinde in der Mitte und mit weißem Endsaum.

Totallänge 81 mm.
Mittelbrazilien.

Ein Exemplar. 81 mm Totallänge, von Mittelbrasilien (JOH. PAUL ARNOLD, Hamburg. G.; die neue Art unterscheidet sich von den wenigen bekannten Arten der Gattung auffällig durch die höhere Anzahl der Strahlen in der Analen (14 gegenüber 9-11) und durch die Färbung.

Ahl, 1936 wrote:Descriptions of three new catfish from Brazil.
By Ernst Ahl.
(Zoological Museum Berlin.)
entered July 14, 1936.

The catfish described below as new were among the consignments sent to the Zoological Museum Berlin by Messrs. ARNOLD, Hamburg, and SCHOLZE and POETZSCHKE, Berlin, for identification. At this point I would like to thank the gentlemen mentioned very much for the beautiful material they sent.

Microglanis ater spec. nov.

Body height 32/3 times the body length, head length 31/2 times. Head slightly wider than long, flat; Rounded snout; Eye 32/3 times the length of the snout, 71/2 times the length of the head, 31/2 times the interorbital width; Maxillary barbel as long as the mental barbel, not reaching to the beginning of the pectoral spine; Postmental barbel even shorter; Mouth wide, the corner in front of the eye; both front jaws of equal length; anterior nostrils clearly tubular; Groups of premaxillary teeth without backward protruding angles.

Dorsal I 6, its distance from the tip of the snout 23/5 times the length of the body; the spine a little over 1/2 the length of the head. Anal 14, rounded. Base of the dorsal, anal and adipose fin about the same length. Pectoral spine strong, with large serrations <Zähnen> all along the margin on both sides, those on the inside considerably larger than those on the outside; the serrations <Zähnen> of the outer edge bent backwards, those of the inner edge bent forward. Ventral just behind the last ray of the dorsal, just reaching the beginning of the anal. Caudal not forked very deeply, the lower lobe slightly larger and longer than the upper, slightly shorter than the head.

Basic color (in alcohol) black, belly gray-white; a very indistinct, barely visible <eben nur angedeutetes>, slightly lighter band over the neck from pectoral to pectoral, a similar, also only weakly indicated band behind the dorsal; a light spot in front of the adipose fin in the middle of the back. All fins are black, the dorsal with a white spot in the middle near the posterior margin, the caudal with a wide, white transverse band in the middle and a white border.

Total length 81 mm.
Central Brazil.

One example, 81 mm total length, from Central Brazil (JOH. PAUL ARNOLD, Hamburg. G.); the new species differs from the few known species of the genus conspicuously in the higher number of rays in the anal (14 compared to 9-11) and in the color.

What I've done here, based on the body proportions, is used a 2006 schematic of and altered the color pattern to match Ahl, then made the following body modifications (by estimates):

• Altered dorsal spine length
• Reduced indentation of caudal fin margin
• Filled in complete vertical dark bar on caudal fin

• Original M. nigripinnis diagram (Sarmento-Soares et al., 2006):
  
• My imagination of M. ater, based on Ahl, 1936:

  

It is but coincidence that I selected M. nigripinnis as the diagram on which to base my drawing, but fortune shined upon me. After creating my drawing, I happened to look at the original description of M. nigripinnis, and there I found this:

Bizerril & Perez-Neto, 1992 wrote:A new pimelodid catfish of the genus Microglanis, collected in a stream at the State of Rio de Janeiro, Brazil, is described. It is similar to M. ater, from Central Brazil, differing mainly in having less anal fin rays and a longer dorsal spine. Ecological notes are included.

Similar to M. ater from central Brazil. Both forms are easily distinguished from all other Microglanis species by their colour pattern, with most of the body black, except for two paler bands, and with the pectoral, ventral, anal, adipose and dorsal fins almost completely black. The new species differs from M. ater mainly in the number of anal fin rays (12 vs 15) and in having a longer dorsal spine (1.52 to 1.75 vs 2.4 in predorsal length).

I did not attempt to alter then number of anal fin rays (since they are not accurately marked in the original M. nigripinnis drawing anyway). But otherwise, this was the best drawing to start with... Who knew? God's grace was with me in figure selection, I guess.

Cheers, Eric

I dug up an old thread (M. iheringi) here where you all discussed the identity of .

That took me back to a paper I already have, the 1946 Review of Microglanis by Gomes, and in there I found a photo of the holotype of . It's very similar to (although I'm not ready to say the same as) the big yellow bumblebees I have.

Cheers, Eric

Also, here is the "Microglanis iheringi" as drawn by Mees (1978). Note that his specimens were collected in Colombia, Cano San Miguel, tributary of the Rio Guatiquia, upper part of the Rio Meta.

Perhaps his fish come from near where my fish originate. I marked up the drawing to reflect the similarity with my yellow fish. Note in my mark-up I also added a dotted line from the black arc on the dorsal fin towards the black slanting bar on the body. I highlight this because on my big fish, the alignment is incomplete (as it also is on the drawing here-the two lines don't line up). But in my smaller fish, the body bar reaches further anterior, so that the fin arc blends into the body's dark slanting bar more precisely.

We need safe passage to Venezuela...

Cheers, Eric

What about the small Microglanis that come mixed in with the large species? Might the large wish with the solid yellow base color be (or M. cf. iheringi) and the smaller fish with the woody base color be ?

Until today, the uniqueness of the two species is isolating, relative to so many other species with the upside down U pattern below the dorsal fin (as contrast to the solid brown mark on the fish I have).

Cheers, Eric

Eric,
At issue here is trying to match your specimens to already described spp when we know that there are no described spp of the genus from the two most common exportation localities (Colombian llanos and Colombian Amazon).
Mees' fish above may be imported given the locality but it is also most certainly not iheringi. This is one of those groups of catfish that, once someone properly digs in and starts comparing material in collections, is going to result in dozens of new descriptions.
-Shane

Thanks Shane. Yes you're right I am trying to do exactly that. Ugh.

Cheers, Eric