Article © Julian Dignall, uploaded October 02, 2015.

The classic British pantomime has several mandatory elements: garish costumes, guest celebrities, slapstick comedy and cross-dressing actors to name a few. The majority of the audience know the plot. It also has, perhaps as its most memorable feature, audience participation. Chief amongst these is the "Oh, yes it is!" and "Oh, no it isn't!" device. This, thankfully more the other features of pantomime, is a phrase we often read and hear when discussing the identification of Corydoras catfish.

When discussing the "true" identification of a particular species online, discussion can indeed quickly drop in to pure Pantomime. Protagonists often forget to include why they have a particular viewpoint and little is achieved or agreed. This is usually because you have someone who's made the point countless times before over a decade or two, because the majority of the audience knows the plot and because at least one person does not. The experienced respondent eventually tires of repeating the story, the poor newbie is bewildered why their question is met with, at best, diffidence.

I suspect history will record that this will be the curse of micro blogging. That seemingly infinite iteration of common questions drives the helpfulness out of the helpful and misinformation will rule because the knowledgeable will have long worn out their keyboards. This is why persistent sites, like PlanetCatfish, are important. While it would be arrogant to claim one source of the truth, it can at least present a consistent and reasoned view. And a view that you and your search engine of choice can find a week, month or decade after it was established.

This is perhaps the longest intro to a catfish of the month to date, but it is relevant because despite a lot of good work and improvement, you can still see the name Corydoras julii attached to fish for sale. The chances are this is incorrect. However, we all have a different view of what "the chances are" means. I don't mean one in a hundred. I mean, in a lifetime of looking at catfishes, then only seeing this fish three times for sale and one of those was in Brazil, the fishes country of origin. Not because they are rare, but because trade routes, fish collectors and other economic forces just mean that that C. julii is not collected, exported and thus kept very often at all. And, it is hard to be sure.

The fish labelled as C. julii is always C. trilineatus. Virtually always. Some folks buy lottery tickets thinking they've got a chance of winning, of course they have a chance. But it is infinitesimal. The same goes for C. julii. Except that if you win the lottery, you will have a lot of money. If you have C. julii then you have a cory with more or less the same financial value as C. trilineatus. Those seeking the cool, have hit the jackpot. By most other measures, there is little gain.

Distance between C. trilineatus and C. julii type localities

Although visually similar, the source areas of the two species are approximately 2720 km or 1690 miles apart and differ in being the upper Amazon main channel towards the west (C. trilineatus) and the C. julii, the Brazilian lowland species found to the east of the continent.

Corydoras julii was described in 1906. It first appeared in aquarium hobby literature in the 60's which is where the problem appears to have started. Between then and now the situation has improved. Twenty years ago, you always saw these fishes mislabelled. Now, it only happens some of the time depending on the country where they are found for sale in the main.

We should not be surprised. Corys that look quite a lot like Corydoras elegans are widespread in the northern half of the continent, C. paleatus has several similar relatives in the south. Corydoras aeneus, as we traditionally know it, is everywhere. Corydoras trilineatus is exported from the upper Amazon, export routes out of Peruvian Iquitos and Colombian Leticia supply the global aquarium trade. It is from eastern Brazil, specifically a creek that flows into the Rio Parnaíba south of the town of Alto Parnaíba, that we see Corydoras julii. The creek was unnamed in the description but because of the co-ordinates given therein, I think it is called the Brejo Chapda.

C. julii is, otherwise a classic round-headed Cory that is easy to keep. Perhaps it should be kept a touch warmer than congeners but it does not require the warm water of, for example, a classic discus aquarium. It has been bred in the aquarium and in terms of husbandry is without exception, a regular Cory.

Copyright information for the images used in this article can be found on the species' full Cat-eLog page.

Cat-eLog Data Sheet
Scientific Name	Hoplisoma julii  Steindachner, 1906
Common Names	Julii Cory Almindelig Leopardpansermalle (Denmark), Julli Cory, Leopard Cory, Panzerwels (Germany)
Type Locality	Creek into R. Parnaíba near Alto Parnaíba (= Victoria), 9°08'S, 45°56'W, Brazil.
Synonym(s)	Corydoras julii
Pronunciation	hop lee so mah - JOOL ee eye
Etymology	This species was named to honour a man, but this man remains a mystery.
Articles	- Shane's World Species An English translation of the description of Corydoras julii
Species Information
Size	52mm or 2" SL. Find near, nearer or same sized spp.
Identification	Often you will see fish for sale as Corydoras julii but they are actually Corydoras trilineatus. So, if you bought as fish as julii, it's almost certainly C. trilineatus from the upper Amazon. The real C. julii will turn up from time to time as although it originates from the upper Parnaiba system in the lower Amazon drainage, it is found in the Rio Para where commercial fish collectors operate. Telling them apart without locality information is actually quite hard as some C. trilineatus can show the spotted head pattern traditionally associated solely with C. julii, C. julii appears also to have a shorter horizontal mid body stripe not reaching half way along the body.
Sexing	Females bigger and fuller bodied.
Habitat Information
Distribution	South America: Lower Amazon River and coastal rivers in northeastern Brazil. Piauí Rivers, Parnaíba (click on these areas to find other species found there) Login to view the map.
IUCN Red List Category	Not Evaluated
Temperature	23.0-26.0°C or 73.4-78.8°F (Show species within this range)
Husbandry Information
Breeding	Unreported.
Breeding Reports	There are 6 breeding reports, read them all here.
Further Information
Reference	Anzeiger der Kaiserlichen Akademie der Wissenschaften, Mathematisch-Naturwissenschaftlichen Classe v. 43, pp 480.
Registered Keepers	There are 167 registered keepers, view all "my cats" data.
Wishlists	Love this species? Click the heart to add it to your wish list. There are 5 wishes to keep this species, see who wants what.
Spotters	Spotted this species somewhere? Click the binoculars! There are 49 records of this fish being seen, view them all.
Forum BBCode
	Search for H. julii
	Look up H. julii on AquaticRepublic.com
	Look up H. julii on Fishbase
	Look up H. julii on Encyclopedia of Life
	Look up H. julii on Global Biodiversity Information Facility
	LFS label creator ARN ref:1.1.1580.378
Last Update	2024 Jun 14 11:17 (species record created: 2015 Oct 02 12:07)

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