Furry Diary

Not furry, but we like them anyway.

Similis Corydoras

Corydoras similis Hieronimus, 1991; listed by FishBase as Hoplisoma simile

Also called Smudge spot cory, Similis cory, Hoplisoma simile (current name in FishBase)

SpeciesShort profile

From Rio Madeira basin in Brazil, South America, where it lives in small tributaries, creeks, pools and seasonally flooded forest.12

A friendly guide, not veterinary advice. For anything about your pet's health, ask your vet.

At a glance the quick version

Length3.8 to 6 cm21
Sizesmall
Very peaceful community fish
Distinctive blue tail-root smudge
Busy, sociable bottom forager
1

Looks how to spot one

Armoured catfish (bony plates, no scales)

A small, compact bottom-dweller protected by rows of bony plates instead of scales, with sensitive barbels around the mouth for searching the substrate. Its signature mark is a dusky bluish smudge on the tail root just in front of the tail fin, which is the easiest way to tell it apart from look-alike spotted corys. Females are usually a little larger and noticeably broader in the body than males.1

Coloursbluish smudge on the caudal peduncle (tail root)1

Personality what they are like

Gentle and easygoing, it gets along with most small, calm tankmates and spends its day sifting the bottom with its group. It grows bolder and more active when kept with plenty of its own kind.1

Daily activity how busy a day looks

Active by day along the bottom, constantly foraging; a stretch of open soft sand lets it root about naturally.1

Grooming and care the hands-on bits

Appreciates clean, stable water, so regular partial water changes and good filtration suit it well. A soft sand substrate helps it forage comfortably with its barbels.1

Home where they are happiest

For a small group, a tank of at least about 45 x 30 x 30 cm (roughly 40 litres) is suggested, though bigger is better. Aim for 21 to 27 C, pH roughly 5.6 to 7.0 and soft to moderately hard water (0 to 12 dGH); FishBase lists a wider tolerance of pH 6.0 to 8.0 and 22 to 26 C.12

Food basics what goes in the bowl

An omnivore. Offer good sinking pellets or tablets as the staple, with live or frozen extras such as daphnia, brine shrimp and bloodworm.1

Company who they like around

A shoaling fish best kept in a group of at least six. Good companions include small tetras, rasboras, gouramis, dwarf cichlids and other peaceful catfish.1

The story where it all began

This cory was formally described by Hieronimus in 1991 from the Madeira drainage of Brazil. It belongs to a large group of spotted Corydoras that look very alike at first glance, and recent taxonomic work has moved it into the genus Hoplisoma.12

Fun facts for the dinner table

  1. 1

    It can gulp air at the surface and absorb oxygen from it, a handy extra when water gets low in oxygen.2

  2. 2

    At first glance it is easily mixed up with several other spotted corys such as C. guapore and C. caudimaculatus; the bluish tail-root smudge is the giveaway.1

  3. 3

    Spawning follows the usual cory routine: eggs are stuck to the aquarium glass and hatch in roughly three to five days.1

  4. 4

    FishBase rates its resilience as high, with populations able to double in under 15 months.2

Recognised by the official bits

IUCN Red List
Least Concern (assessed 7 November 2018)2
Taxonomy
Described by Hieronimus in 1991; FishBase now places it in the genus Hoplisoma as H. simile2
Family
Callichthyidae (armoured catfishes), order Siluriformes1

The care rhythm Furry Diary remembers it for you

A typical home-care rhythm for a Similis Corydoras. It is our own starting plan, not a vet's advice, and you can change every line in the app.

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Owner questions the things everyone asks

How often should I feed my Similis Corydoras?

Feed small amounts once or twice a day. Furry Diary's starting plan suggests daily feeding. Watch that all food is eaten within a few minutes to keep water clean.1 Furry Diary plan

What does a Similis Corydoras eat, and what should it never eat?

It's an omnivore that enjoys sinking pellets or tablets as a staple, plus live or frozen treats like daphnia, brine shrimp and bloodworm. Avoid any food that is too large or floats, as it feeds at the bottom.1

How much space does a Similis Corydoras need?

For a small group, a tank of at least 45 x 30 x 30 cm (roughly 40 litres) is suggested, though bigger is better. A soft sand substrate helps it forage comfortably.1

What temperature, light or water does a Similis Corydoras need?

Aim for 21 to 27°C, pH roughly 5.6 to 7.0 and soft to moderately hard water (0 to 12 dGH). It appreciates clean, stable water with good filtration.12

How often should I clean a Similis Corydoras's home?

Furry Diary's starting plan suggests a weekly 25% water change, weekly glass cleaning, and a monthly filter rinse in old tank water. Regular partial water changes keep it healthy. Furry Diary plan

Can a Similis Corydoras live with others?

Yes, it's gentle and easygoing, best kept in a group of at least six. Good companions include small tetras, rasboras, gouramis, dwarf cichlids and other peaceful catfish.1

How long does a Similis Corydoras live?

Lifespan varies depending on care and environment. For specific details, please ask a good breeder or an exotic-pet vet.

Can I handle a Similis Corydoras?

It's best not to handle this fish; it has sensitive barbels and bony plates. Use a soft net if you need to move it, and always keep it in water.1

Written from the sources on this page, a few checked guides (VCA, ASPCA, RSPCA) and Furry Diary's own starting care plan. A friendly guide, not a vet's advice.

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Where this comes from

Every breed page shows where each fact comes from. If we got something wrong, sorry, we are pet people, not a science magazine. Tell us at support@furrydiary.app and we will fix it.

  1. Seriously Fish: Corydoras similis seriouslyfish.comused for origin, habitat, size, care, behaviour, dimorphism, breeding, similar species
  2. FishBase: Hoplisoma simile (Smudge spot cory) fishbase.seused for taxonomy, describer, size, water parameters, IUCN, air breathing
  3. VCA Animal Hospitals: Feeding times and frequency for your dog vcahospitals.comused for owner questions
  4. ASPCA: Dog grooming tips aspca.orgused for owner questions
  5. ASPCA: Cat grooming tips aspca.orgused for owner questions
  6. ASPCA: People foods to avoid feeding your pets aspca.orgused for owner questions
  7. RSPCA: What to feed your rabbit rspca.org.ukused for owner questions

Checked 2026-09-30. Text is written in our own words from these sources.