Rupture of cells in a solution as a result of a sudden reduction in osmotic pressure. Can cause severe issues in fishes when the chemical composition of the water changes rapidly, e.g., during or following a pH crash.
Glossary: osmotic shock
Glossary: osseus
Composed of, containing, or resembling bone; bony.
Glossary: ossicle
Small bone, especially any of the three small bones in the inner ear of vertebrates.
Glossary: ossification
The natural process of bone formation.
Glossary: ossify
To change into bony or become bony.
Glossary: Ostariophysan
Fish of the superorder Ostariophysi, members of which are characterised by possession of a Weberian apparatus, i.e., the anterior four or five vertebrae are modified as a protective casing for the bony ossicles which connect the inner ear and swim bladder. The order contains such orders as Cypriniformes, Characiformes, Gymnotiformes, and Siluriformes.
Glossary: Osteichthyes
Superclass of fishes possessing bony, as opposed to cartilaginous, skeletons. Also known as bony fishes.
Glossary: osteocranium
The bony part of the skull.
Glossary: osteology
Study of the structure and function of bones.
Glossary: ostracod
Any member of the crustacean class Ostracoda.
Glossary: Ostracoda
Class of crustacean, sometimes referred to as seed shrimp, characterised by possession of a bivalve-like protective carapace. Found in both freshwater and marine environments, and sometimes used as food for small fishes in aquaria.
Glossary: otolith
Calcareous structures contained within the inner ear of most fishes, functioning to provide a sense of balance in a similar way to the inner ear in humans, as well as aiding in hearing. Also known as ear bones, ear stones or statoliths. Accumulate layers of calcium carbonate and gelatinous matrix as a fish ages, these forming […]
Glossary: outcross
The process of outcrossing or offspring resulting from it.
Glossary: outcrossing
A cross between relatively unrelated individuals; the introduction of unrelated genetic material into a breeding line. Often used to raise or maintain genetic diversity.
Glossary: outgroup
In phylogenetics, a group of organisms serving as a reference and comparison to the groups being studied. Opposite of ingroup.
Glossary: ova
Plural of ovum.
Glossary: overstock
To add more fishes to an aquarium than it is capable of maintaining in a biological or physical sense.
Glossary: oviparous
Producing eggs which hatch outside the body, as in most fishes.
Glossary: oviposit
To deposit an egg during a spawning event,
Glossary: ovipositor
Tubular structure used to deposit eggs in some fishes. Formed by an extension of the genital opening and usually concealed but sometimes becomes visible prior to spawning. Also referred to as the genital papilla.
Responsive design
it is a complete malfunctioning horror on iphone and ipad.
10th Nov 2024
Major Changes in New World Cichlid Taxonomy
Reclassification of Genera: Several genera have been reclassified or merged. For example, the genus Cichlasoma has been split into multiple genera, an...
6th Nov 2024
Aphyosemion rectogoense
Many thanks cyprin, the image has now been removed.
31st Oct 2024
Product reviewers wanted
Hello! Very much interested in writing for you, please include me in the info. Thank you for the opportunity!
6th Sep 2020
Product reviewers wanted
I would be interested in reviewing products. Before retiring I was a technical writer and managed a Quality Management Program.
30th Aug 2020