Common Fish Names Beginning With O

Astronotus ocellatus - Oscar
Red Oscar. Einar Haraldsson

Read about a variety of fish, from the polka dotted Ocellated Synodontis to the snakehead, that begin with the letter O.

Common Fish Names That Begin With O

  • Obese Synodontis - Synodontis obesus: Synodontis catfish originate from the rivers and lakes of Central and West Africa. They are scavengers and will roam around the bottom of the tank. Use fine sand as a substrate for these catfish because they have very sensitive whiskers (called "barbels"). Sharp gravel and large substrates can tear their whiskers which might lead infection. Their barbels are used to smell food which they can locate far away, even wedged in corners or stuck under rocks.
  • Obliquidens Hap - Haplochromis obliquidens: The adult makes exhibits yellow coloring with a red blotch near the gill cover. They also have "egg" spots on the anal fin. Females, however, are a dull gray. When these pairs spawn, they are very fertile and make terrific parents. Females can live with the fry for months without issue.
  • Obscure Snakehead - Parachanna obscura:  This medium-sized fish is carnivorous. Its elongated body is tapered on both ends and is covered in scales. The long head looks like a snake (giving the fish its name) and it's also covered with scales a bit larger than those on the body.
  • Ocellated Freshwater Stingray - The fish originates in Brazil, Uruguay, and Paraguay and grows up to 39 inches long. The Ocellated Freshwater Stingray is a fish appropriate for a specialist fishkeeper with a species tank.
  • Ocellated Laprologus - Lamprologus ocellatus: This adorable little cichlid with a big personality is a popular fish among hobbyists. It displays a cute habit of burying itself in a shell in self-defense. Unware fishkeepers are subject to a sharp nip from an Ocellatus who thinks you're invading its territory.
  • Ocellated Loach - Acanthocobitis urophthalmus: This fish comes from Sri Lanka's fast flowing streams and requires a tank that simulates this environment. It likes high oxygen content, a good current, bogwood and stone décor, along with fine gravel or sand substrate. This peaceful  Loach lives on the bottom and likes tank mates of its own kind. It cohabitates well fish of a similar size that likes the same conditions, such as Zebra Danios.
  • Ocellated Shell-Dweller - Neolamprologus kungweensis: This territorial fish that will aggressively defend its shell and nearby area. Tank mate options include small rock dwellers and fish that will reside in other areas of the aquarium.
  • Ocellated Synodontis - Synodontis ocelli fern: The Ocellated Synodontis is eye catching with its polka dots. It's easy to care for and a perfect fish for beginners. It does need a large 50-gallon tank, though, and since the young are pH sensitive, it's best to start off with adult fish.

More Fish That Begin With the Letter "O"

  • Odynea Pimelodid Catfish - Pimelodella chagresi odynea
  • One-Gilled Swamp Eel - Ophisternon bengalense
  • One-Lined Pencilfish - Nannobrycon unifasciatus
  • One-Spot Synodontis - Synodontis notatus
  • Opaline Gourami - Trichogaster trichopterus
  • Orange Chromide - Etroplus maculatus
  • Orange-Finned Loach - Botia modesta
  • Orange-Lined Cichlid - Melanochromis joanjohnsonae
  • Oriental Snakehead - Channa orientalis
  • Ornate Bichir - Polypterus ornatipinnis
  • Ornate Ctenopoma - Ctenopoma ansorgii
  • Ornate Fin Nipper - Ichthyborus ornatus
  • Ornate Pimelodus - Pimelodus ornatus
  • Oscar - Astronotus ocellatus
  • Otocinclus - Otocinclus affinis
  • Oxeye Herring - Megalops cyprinoldes
  • Ozola Barb - Barilius barna

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