Catfish of the Month Right September 1999

Olga Cory - Corydoras simulatus   Weitzman & Nijssen, 1970

Article © Ian Fuller, uploaded September 01, 1999.

Once more we have a featured Corydoras and, more importantly, once more it is introduced to us by cory guru, Ian Fuller. My thanks to Ian for the article this month as it allows me to concentrate on writing other things such as Grooms wedding speeches.... I digress, back to the fish, Ian?

Corydoras simulatus is a long snouted species, growing to around 70 millimetres often referred to as saddle snouted because of its concave snout shape. It was given its name because of the similarity of its colour pattern to the smaller rounded nose species Corydoras metae Eigenmann, 1914. Both species come from the Rio Meta in the Meta province of Colombia. Corydoras simulatus also display variability in its colour pattern, with two distinct colour forms known, which are often present within single populations. The classic pattern shows a plain tan coloured body with a narrow black band extending from the base of the dorsal fin along the ridge of the back and down across the caudal peduncle. The colour pattern of the less frequently seen variants show an additional dark, often intense, black triangular blotch along the centre of the body. Both variants also have a black vertical eye mask.

For a number of years the specimens of Corydoras simulatus showing the large triangular body blotch were thought to be another similar looking, also variable, species from the Amapa region of eastern Brazil, namely Corydoras amapaensis Nijssen, 1972. Fortunately this colour form of Corydoras amapaensis is quite rare in the hobby and the identification problem does not often arise. Where these species differ visually is in the base body colour and in body depth. The body colour of Corydoras amapaensis tend to be lighter with a silvery appearance, the depth is also considerably shallower.

Corydoras simulatus is an undemanding species and will tolerate a wide range of water conditions, however extremes should be avoided and any changes made should be gradual, with the exception of temperature when attempts to trigger spawning activity are made. The typical temperature drop made during water changes will often induce spawning activity; in fact this is one of the few long nosed species that has been successfully bred under aquarium conditions on a fairly regular basis. The species is best kept in a tank having a fine sand substrate in which it will often be seen burying head first, almost up to its eyes in its search for food particles. Other tank furnishings are a matter of personal taste, but the addition of some live plants, bog wood and a little leaf litter and will afford the fish with more natural surroundings.

The dietary requirements of this species are typical for the genus and in nature would consist of small insect larvae, crustaceans, worms and micro organisms found in the bio-film, which forms on submerged rocks, tree roots and fallen branches. In aquaria they will accept most commercially prepared flake, tablet and granular foods, However to keep them in the best of health their diet should be varied and where possible include live offerings such as Daphnia, blood worm, tubifex and chopped earth worms.

Down Cat-eLog Data Sheet
Scientific Name Corydoras simulatus  Weitzman & Nijssen, 1970
Common Name Olga Cory
Type Locality Río Ocoá near Puerto López, 4°06'N, 72°57'W, R. Meta system, Meta, Colombia.
Pronunciation kor ee doh rass (lineage one).
Etymology Cory = helmet, doras = skin. In this case it was incorrectly used to mean armour (cuirasse) instead of skin in allusion to the dual rows of plates that run along the flanks of this genus. This specific epithet literally means imitation(simulatus=imitation, copy), in reference to its similarity to Corydoras metae.
Down Species Information
Size 49mm or 1.9" SL. Find near, nearer or same sized spp.
Identification Corydoras are identified by their twin rows of armour plates along the flanks and by having fewer than 10 dorsal fin rays. They are most commonly confused with the other genera in the sub-family, namely Brochis, Scleromystax and Aspidoras.

A long snouted species, having a tan coloured body with a black band along the ridge of the back from the base of the dorsal to and across the caudal peduncle. There is also a black vertical eye mask.
Sexing Sexing Corydoradinae catfishes
General Remarks This species is one of only four which posses a third pair of rictal barbels, these are only small and can only be seen when the larger outer barbels are in a forward position.
Down Habitat Information
Distribution South America: Upper Meta River in Colombia.
Orinoco, Middle Orinoco, Meta, Upper Meta (click on these areas to find other species found there)

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IUCN Red List Category Vulnerable, range map and more is available on the IUCN species page. Last assessed 2020.
pH 6.2 - 6.4
Temperature 20.0-25.0°C or 68-77°F (Show species within this range)
Down Husbandry Information
Feeding Will accept most commercial flake, tablet and granular foods. Small crustaceans, worms and insect larvae form the basis of their natural diet and where ever possible should be offered as and when available.
Furniture Fine smooth grained sand substrate.
Compatibility Peaceful, but may become aggressive to own kind during mating season.
Suggested Tankmates Any non-boisterous fish.
Breeding C. simulatus were spawned in a fish house in the U.K. where the heating was turned off at the end of April and back on again towards the end of September. This resulted in a 24 hour temperature variation of between 8 and 10 °F. Weekly water changes were made as normal, no extra cooling was needed to trigger the spawning. When the fish were ready they followed the normal Cory 'T' formation mating clinches and spawned. A single female produced 150 1.5mm diameter light amber eggs. These were placed on the tank sides and in the spawning mops. Spawning mops should be provided as the fish appeared to prefer these to Java Moss.
Breeding Reports There is but a single breeding report, read it here.
Down Further Information
Reference Beaufortia v. 18 (no. 233), pp 126, Figs. 4, 6d.
Registered Keepers Keeping this species? Why not .
There are 25 registered keepers, view all "my cats" data.
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There are 8 records of this fish being seen, view them all.
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Last Update 2020 Oct 22 04:38 (species record created: 1999 Sep 01 11:22)

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