Article © Amanda Parker, uploaded July 26, 2010.
| Acidity | The amount of acid present in a solution, often expressed in terms of pH. | More... |
| Acidosis | Low pH in the blood of a fish (or other animal). May be caused by a sudden drop in aquarium pH (see pH Crash). Can be fatal. | More... |
| Acoustic | Relating to the sense of sound and/or vibration. | More... |
| Adhesive Spawner | A species that lays eggs that stick to a surface. | More... |
| Adipose Fin | A fin on the dorsal surface that is located between the dorsal fin and the caudal fin. The adipose fin is composed of fatty tissue and (rarely) a leading hard ray or a few soft rays as seen in some catfishes such as most Callichthyidae, Loricariidae and the Indian Whiptail catfish, Sisor (Sisoridae). | More... |
| Adult | A fish capable of reproducing successfully. | More... |
| Aeration | The process of passing air through water to exchange gasses. In an aquarium, this may be done withan airpump and airstone or a powerhead. | More... |
| Aerobic | Life requiring free oxygen. | More... |
| aff. | Literally means "affinis." An animal appears related but is different. | More... |
| Agressive mimicry | A form of similarity in which a preadator gains an advantage by taking a resemblance to its prey or a resemblance to a species which its prey does not find a threat. eg.some lepidophage(scale eating)fish do this to get close to their prey. | More... |
| Alarm Substance | Also called Schreckstoff. A compound unique to a group of fishes known as the Ostariophysi (which includes Catfishes).When the skin of an Ostariophysan is damaged, special cells rupture and release Alarm Substance, warningother members of the shoal of imminent danger. | More... |
| Albino | An animal lacking pigmentation causing the animal to appear white. A true albino has red eyes. | More... |
| Alimentary Canal | The complete digestive tract from mouth to anus. | More... |
| Alkalosis | High pH in the blood of a fish (or other animal). Generally caused by a sudden move from water oflow pH to high pH without an acclimitization process. | More... |
| Allele | Alternative forms of genes. Example: For the gene controlling pigmentation, there are two forms: normallypigmented and albino. Also see gene. | More... |
| Amelanism | An animal lacking black pigment. Yellow and red pigments are present. This animal is nota "true" Albino. Also see Leucism and Xanthism. | More... |
| Ammonia | NH3/NH4 ions. Ammonia is the first stage of the breakdown of fish waste, food and plant matter inwater. The odor is very strong and distinctive. Can be converted to nitrite by "good bacteria." See also Nitrogen cycle. | More... |
| Anadromous | Fish who spend their lives in the ocean and migrate to freshwater when it is time to spawn. | More... |
| Anaerobic | Life that does not require free oxygen. | More... |
| Analagous | A structure that resembles another structure in function, but not in form. | More... |
| Anastamosis | The joining of multiple structures into a single network. May apply to anatomy (blood vessels) andgeography (rivers). Plural: Anastamoses. | More... |
| Anoxia | A lack of free oxygen. | More... |
| Anterior | Toward the front. | More... |
| Anthropogenic | Relating to the impact(usually negative) of humans on an environment. | More... |
| Anthropomorphic | Giving human attributes to animals. Example: Bugs Bunny is able to walk like a human being. This isthe Anthropomorphization of an animal. | More... |
| Aquarium | An enclosure, such as a glass tank, outfitted with lifesupport equipment for the purpose ofkeeping underwater animals and plants alive. | More... |
| Armoured | A fish having a protective outer covering such as Scutes, Bony Plates and/or Scales. | More... |
| Aufwuchs | Literally meaning "growth" in German. Non-burrowing organisms that grow on the substrateforming a coating of detritus. | More... |
| Axanthic | An animal lacking yellow pigmentation. The animal will be entirely black. | More... |
| Axillary | From the latin axilla meaning armpit or underarm | More... |
| Backwater | A quiet pool off of a stream. | More... |
| Barbels | Threadlike projections that extend from the corners of the mouth or beneath the chinof catfish. Sometimes called "whiskers." Barbels are covered with taste buds. | More... |
| Batesian mimicry | Similar bright colors or patterns being used as a warning system between unrelated animals but one or more may not be noxious animals. | More... |
| Benthic | Living at the bottom of a lake, river or ocean. | More... |
| Benthopelagic | Capable of living near the bottom, middle and/or upper levels of a lake, river or ocean. | More... |
| Bifurcated | Forked or divided in two parts. Some catfishes have a Bifurcated caudal fin. | More... |
| Biodiversity | The sum total of all living things in an ecosystem. | More... |
| Biofilm | A mix of microorganisms whose cells are adhered to each other on surfaces of the aquarium. | More... |
| Bioload | The demand on lifesupport systems created by aquarium occupants. The more fish there are in an aquarium,the greater the Bioload. | More... |
| Bioregion | A geographical area described in terms of its unique combination of plants, animals, geology, climate and water features, an area defined by natural boundaries and distinct living communities rather than artificial borders. Sometimes called an Ecoregion. | More... |
| Biotope | A portion of an ecosystem with specific conditions and life forms. An aquarium may be setup to reflect a specific Biotope, such as a river from a particular region. | More... |
| Blackwater | A type of soft, tropical water that supports unique plants and animals. Blackwater occurs when tannic acids fromnearby vegetation seep into the water. In an aquarium, bogwood and additives may help acheive this effect. | More... |
| Bogwood | Waterlogged wood used for the aquarium. More safely bought at an aquatic retailer, but can be collected from rivers or lakes. Will often leach tannic acid into the aquarium water which can be desirable for certain species, but makes the water appear tea-like. | More... |
| Brackish | Water that has some salt added. This occurs in nature, for example in tidal estuaries | More... |
| Branchial | Of the gills. | More... |
| Breeding | The measures required for a male and female from a certain species to produce offspring. | More... |
| Brine Shrimp | Artemia salina. A common fish food. | More... |
| Brood | A group of offspring that arises from a clutch of eggs. | More... |
| Bubblenest | A nest for females to lay eggs in, built by one or both parents, from secretions and air. | More... |
| Buccal | Of the mouth and/or cheeks. | More... |
| Buoyancy | The ability to float. | More... |
| Bycatch | The accidental capture of species "X" during the targeted capture of species "Y." | More... |
| Carnivore | A species which will primarily eat meat based foods. | More... |
| Casque | Helmet-shaped. | More... |
| Catadromous | Fish who spend their lives in freshwater and migrate to the ocean when it is time to spawn. | More... |
| Caudal | Of the tail. | More... |
| Caudal Fin | The tail fin. | More... |
| Caudal Peduncle | The base of the tail which acts as a "wrist." | More... |
| Cave Spawner | A species that lays eggs in a cave. | More... |
| cf. | Literally means "confer." An animal appears similar to an identified species, but without certainty or confirmation. | More... |
| Channel | The main part of a river. | More... |
| Chelation | A chemical method of binding metals such as iron for use in plant fertilization. | More... |
| Chloramine | A chemical compound commonly added to the domestic water supply as a disinfectant. Chloramineis a combination of ammonia and clorine and is more potent than chlorine alone.Many dechlorinators will also remove Chloramine(make sure to check the label). | More... |
| Chlorine | A chemical commonly added to the domestic water supply as a disinfectant. Chlorine acts as an irritant onfish and also kills "good bacteria." Aerate the water for 24 hours or use a dechlorinating agent to removeit from the water. | More... |
| CITES | An abbreviation for Convention on International Trade in Endangered Species of Wild Flora and Fauna.An agreement among governments to restrict trade in species that are endangered and threatened. | More... |
| Cleithrum | A bow-shaped dermal bone of the pectoral girdle. It extends upward from the pectoral fin base along the posterior margin of the gill cavity. It is typically the first large bone visible on the body posterior to the operculum. | More... |
| CLOFFSCA | "Checklist of Freshwater Fish in South and Central America." A book listing the species found infreshwater in South and Central America, with brief reference to original description, synonyms, distributionand maximum size. The data in this book can also be found in Fishbase. | More... |
| Clutch | A group of eggs laid in the same place at the same time. Many catfishes lay their eggs in clutches. | More... |
| COF | Catalog of Fishes. A list of all species of fish which can be found on-line here. | More... |
| Commercial Extinction | A food fish no longer common enough to be profitable. | More... |
| Common Name | The vernacular name for a species. Common Names may vary by location and/or language and often cause confusion.Different species can have the same Common Name and one species can have several Common Names. | More... |
| Community Fish | Fish that will live with other species of fish and not cause eitherthemselves or their tankmates any trouble. Also can imply the fish will adapt to abroad range of water conditions, although this should not be assumed. | More... |
| Compatibility | The ability of a species to live with others. | More... |
| Compressed | Flattened from side to side. | More... |
| Concave | Curved inward. | More... |
| Condition | To prepare fish for spawning. Example: by feeding particularly nutritious foods. | More... |
| Conductivity | Literally, the measure of electricity through water. For aquarists, this translates into a measurement of which ions such as calcium, hydrogen, sodium, etc. may be present in the water. A very high level of Conductivity could indicate either polluted water or water with too many additives (i.e. plant fertilizers or food). Water with very low Conductivity may be achieved through reverse osmosis filtration, deionization or distillation.Conductivity is measured by an electronic meter, using units of microSeimens/cm. Related to TDS. | More... |
| Congener | One or more species belonging to the same genus. | More... |
| Consanguinity | Relationship by blood or by a common ancestor. (from the Latin consanguinitas) | More... |
| Conspecific | Belonging to the same species. | More... |
| Contaminant | A fishkeeping term in which species "X" in found in a shipment of species "Y." This could be due to Bycatch, ordeliberate/accidental mixing by the fisherman/exporters/importers. | More... |
| Convex | Curved outward. | More... |
| Cool Links | Offramps of interest on the information superhighway. | More... |
| Coprophagy | Coprophagy refers to many kinds of feces eating, including eating feces of other species (heterospecifics), of other individuals (allocoprophagy), or its own (autocoprophagy) ??? those once deposited or taken directly from the anus. | More... |
| Coracoid | The ventral-most paired bone of the pectoral girdle. It attaches antero-dorsally to the cleithrum and ventrally the left and right coracoids attach together. In some catfish, the coracoid has an extended or reduced "posterior process" which can be used for species identification. | More... |
| Cordiform | heart-shaped | More... |
| Courtship | Ritualistic behaviors that occur prior to spawning. | More... |
| Crepuscular | A species which is normally active in the half light of dusk and dawn. | More... |
| Crustaceans | A mainly aquatic group of animals that has a hard outer skeleton for protection. Included inthis group are shrimp, lobster, crab and barnacles. | More... |
| Cyanobacteria | Small and usually unicellular bacteria that are aquatic and photosynthetic. Distinction of having the oldest known fossil records. | More... |
| Cyclops | A type of copepod rangeing in size from 1-3 mm., often used live or frozen as fish food. Called a Cyclops because of the single eye spot. | More... |
| Daphnia | A type of water flea which is used as a fish food. | More... |
| Deionization | A process where water is filtered through ion-exchange resins. | More... |
| Dentition | The arrangement of teeth. | More... |
| Depressed | Flattened from top to bottom. | More... |
| Dermal | Something that is located in, derived from or related to the skin. | More... |
| Detritus | Also called mulm. Uneaten food, dead plant matter and faeces which accumulates at the bottom ofa fish tank. Detritus is full of nutrients and promotes the growth of unwanted algae. | More... |
| Dimorphic | Having two or more forms. Often, male and female catfish of the same species are quite distinct in appearance.Such species are said to be sexually dimorphic. | More... |
| Distal | Away from a point of reference, usually the center of the body. Opposite: proximal. | More... |
| Distilled Water | Water with nothing in it except dissolved gasses. This is the purest type of filtered water. | More... |
| Distribution | An indication of how widespread or abundant a species is. | More... |
| Dither Fish | A fish or group of fish added to a tank that help other tank occupants feel safe and come out of hiding. | More... |
| Diurnal | Happening during the day, or daily. | More... |
| Dorsal | Of the back. | More... |
| Dorsum | With fish this refers to the upper side of the head or body. | More... |
| Earthworm | Common Earthworms are sometimes used as a fish food. | More... |
| Ecoregion | A geographical area described in terms of its unique combination of plants, animals, geology, climate and water features, an area defined by natural boundaries and distinct living communities rather than artificial borders. Sometimes called a Bioregion. | More... |
| Ectotherm | A species whose body temperature is determined by its surroundings, i.e. "cold-blooded." | More... |
| Electrogenic Organ | An organ present in some fishes that generates an electrical current to locate food and/or prey. | More... |
| Electroreceptive Organ | An organ present in some fishes that allows for "listening" to electrical signals. | More... |
| Emarginate | Slightly indented. | More... |
| Endangered Species | An animal or plant that is very close to extinction. | More... |
| Endemic | A species restricted or contained in a specific area. | More... |
| Epibenthic | Living on the surface of the bottom in a body of water. | More... |
| Epiphytic | Plants (bolbitis, Anubias, Java Fern, etc.) that are not inserted in a substrate but are attached to surfaces. | More... |
| Erectile | Used to describe spines that can be raised and often locked into place. | More... |
| Estuary | A type of ecosystem that occurs when a river runs into the ocean. An Estuary will have variablesaline levels. | More... |
| Etymology | The origin or meaning of a word. | More... |
| Euryhaline | Life capable of tolerating a wide range of salinities. | More... |
| Euthanasia | The practice of ending a life in a manner which relieves pain and suffering. | More... |
| Evaporation | Conversion from a liquid state to a gaseous state. | More... |
| Evaporative Concentration | The process where dissolved substances become stronger when water evaporates. Example: Betweenwater changes in an aquarium, water will evaporate causing waste products (nitrites, nitrates, etc.)to become more intense. This is called Evaporative Concentration. | More... |
| Evertible | The ability to turn inside-out. | More... |
| Evolution | The historical development of species, in which genetic traits may be transferred over generations vianatural selection. | More... |
| F0 | An original set of parents in a breeding program. May also refer to a wild-caught fish kept in captivity. | More... |
| F1 | The first filial generation. May also refer to the first children of a particular set of wild-caught parents (F0).All children of the F0 parents will be considered F1. | More... |
| F2 | The second filial generation. May also refer to the "grandchildren" of a particular set of wild-caught parents (F0).All "grandchildren" of the F0 parents will be considered F2. | More... |
| Falcate | Sickle-shaped, curved and tapering to a point. | More... |
| Family | A taxonomic grouping between Order and Genus. A group of related Genera. | More... |
| Fecund | A species with a high reproductive rate. | More... |
| Fecundity | The potential rate of reproduction of a species. | More... |
| Feeding | Advice on what this species eats. See Carnivore,Limnivore and Omnivore. | More... |
| Fertilization | The process where a female reproductive cell and a male reproductive cell successfully join to form offspring. | More... |
| Filamentous | Having thin, thread-like projections. | More... |
| Filter | Any device that maintains water quality. The common types are power (or hang-on-back),canister and internal. For more information, see this article. | More... |
| Finfold | A "full-body" fin in a larval fish that will develop into the the dorsal, caudal and anal fins of an adult fish. | More... |
| FishBase | Universal computerized databases of fishes available here. | More... |
| Fishless cycling | Cycling is the procedure where an aquarium, and in particular it's filtration system, builds up "beneficial/good bacteria". The fishless part refers to using a source of ammonia other than fish, to avoid the fish being exposed to ammonia and nitrite levels unnecessarily. See also Nitrogen cycle. | More... |
| Flashing | When a fish "scratches" on objects in the aquarium. This may be due to an irritation, such as an external parasite. | More... |
| Fluviatile | Existing in or about rivers or streams. | More... |
| Fork Length | abbr. FL The distance from the tip of the snout to the fork of the tail. | More... |
| Fractional Spawner | Eggs are released a few at a time over a number of days as opposed to all at once. | More... |
| Freshwater | Characterized by having low concentrations of dissolved salts and other total dissolved solids as opposed to seawater and brackish water. Also sometimes called "sweet water". | More... |
| Fry | Another term for a larvae or juvenile fish. | More... |
| Furniture | The way to decorate a tank. Also see Bogwood and Substrate. | More... |
| Fusiform | Tapered on both ends. Cigar-shaped. | More... |
| Gene | A region of DNA that determines a trait of an organism. There are two copies of each gene in an organism.One is inherited from the mother. The other is inherited from the father. Also see allele. | More... |
| Genera | Plural of Genus. | More... |
| General Remarks | Notes of interest on a species. | More... |
| Genital Papilla | In some fishes, a tube extending from the genital pore, behind the anus. | More... |
| Genus | A taxonomic grouping between Family and Species. A group of related Species. | More... |
| Gestation | The time between fertilization and hatching. | More... |
| GFCI | An abbreviation for "Ground Fault Circuit Interrupter." A type of electrical outlet that opens the circuit whenexcess amperage is detected. A safety device more commonly used in the United States and installed inindividual electrical outlets. Also see RCD. | More... |
| GH | An abbreviation for Gesamthärte, literally meaning "Total Hardness" in German. A laboratory standard formeasuring the concentration of calcium and magnesium ions in water. | More... |
| Gills | Respiratory organs of fish. | More... |
| Gland | An organ in the body that synthesizes a substance. | More... |
| Gonads | Reproductive organs. Ovaries in females. Testes in males. | More... |
| Gonopodium | The modified anal fin of a Livebearer male used to deliver sperm to the female's vent. | More... |
| GPD | Gallons per day. | More... |
| Gravid | Referring to a female full with eggs. | More... |
| Grazing | Method of feeding in which a fish feeds on the biofilm which grows on surfaces in the water. | More... |
| Green water | Suspended microscopic algae giving an overall green appearance to a container of water. | More... |
| Gustatory | Relating to the sense of taste. | More... |
| Habitat | Where a species lives. | More... |
| Hardness | The amount of calcium and magnesium ions in water. May be measured in ppm (parts per million)or mg/l (milligrams per liter). Hard water has more than 200 ppm. Soft water has less than 100 ppm. | More... |
| Head Length | Abbr. HL. The distance from the tip of the snout to the end of the operculum. | More... |
| Herbivore | A species which will primarily eat vegetable based foods. Herbivores may also eat small amounts of meat based food. | More... |
| Heterospecific | From a different species. | More... |
| Hierarchy | Social structure within a group of fishes. | More... |
| Hits | A simple counter of how often a particular data sheet, image or article has been viewed. | More... |
| Holotype | The single specimen (or part of a specimen in the case of fossil taxa) designatedas the name-bearing type of the species. | More... |
| Homologous | A structure that resembles another structure in form, but not in function. | More... |
| Hospital Tank | Also called a Quarantine Tank. A tank set up to hold fish that need medical treatment and/or isolation. | More... |
| Husbandry | Seeing to the overall care and welfare of an animal. | More... |
| Hyaline | In ichthyology the term usage denotes a type of colorless, transparent substance. | More... |
| Hybrid | Offspring who have two distinctly different species as parents. | More... |
| Hybridogenesis | It occurs in some animals that are hybrids between species. | More... |
| Hydra | A genus of simple fresh-water, predatory animals possessing radial symmetry belonging to the phylum Cnidaria and the class Hydrozoa. | More... |
| Hyperoxia | The actual oxygen concentration is higher than the oxygen concentration of water fully equilibrated with air. | More... |
| Hypogean | Living or occurring under the earth's surface. | More... |
| Hypoxia | The actual oxygen concentration is lower than the oxygen concentration of water fully equilibrated with air. | More... |
| Ichthyology | The scientific study of fishes. | More... |
| Ichthyotoxic | Poisonous to fish. | More... |
| ICZN | An abbreviation for "International Commission on Zoological Nomenclature." The governing body that sets thestandards for naming plants and animals. The standards may be found here. | More... |
| Identification | What to look for when trying to find out what type of species you are looking at. | More... |
| Immunity | The ability of an organism to overcome a pathogen. | More... |
| Inbreeding | When close relatives mate. Examples: A mother with a son. A father with a daughter. A brother with a sister.This is generally considered bad breeding practice as it reduces genetic variability and increases the risk ofdeformities. Inbreeding may be used to create specific traits, such as long fins or color morphs (albinos). | More... |
| Indigenous | Native, but not endemic. Also see Native and Endemic. | More... |
| Inferior | Directed downward. In Icthyology, also refers to a mouth directed downward. | More... |
| Infusoria | Miscellaneous microorganisms found in detritus. When properly cultured, Infusoria make an excellent fry food. | More... |
| Inorganic | A chemical compound which is not carbon-hydrogen based. | More... |
| Insectivore | Species that eats insects as its main diet. | More... |
| Interopercle | One of a series of bones which makes up the Operculum. | More... |
| Introduced | Describing a species that humans have released into a particular area. | More... |
| Invasive | An introduced species of plant or animal that causes damage to an ecosystem. | More... |
| Invertebrate | An animal without a backbone. | More... |
| IUCN | International Union for Conservation of Nature. An organisation started in 1948 to support and coordinate conservation efforts all over the world. In particular, they publish a list of species showing how endangered they are in the IUCN Red List. | More... |
| IUCN Red List | A list from IUCN of species and their status from a conservation perspective, ranging from Least Concern to Extinct. The list is searchable on http://www.iucnredlist.org/. The IUCN red list is the basis for the CITES trading restrictions. | More... |
| Junior Synonym | The later established of two synonyms. A Senior Synonym has priority over a Junior Synonym. | More... |
| Juvenile | The post-larval stage of a fish where much differentiation and change occurs. | More... |
| Keel | A narrow, hard ridge. | More... |
| KH | An abbreviation for Karbonathärte, literally meaning "Carbonate Hardness" in German. A laboratory standard formeasuring the concentration of calcium and magnesium carbonates in water. | More... |
| Krill | The common name given to the order Euphausiacea of shrimp-like marine crustaceans and available frozen as aquarium fish food. | More... |
| Labyrinth Organ | Also called Accessory Breathing Organ. A lung-like apparatus found in certain fishes which allows them to breath air. | More... |
| Lacustrine | Of lakes. | More... |
| Larva | The state a fish after it has hatched but before it is free-swimming. | More... |
| Lateral | Of the side(s). | More... |
| Lateral Line | A sensory canal (which branches into pores) that runs through the body of a fish. The lateral linecan vary in length depending on the species. The lateral line is very important in detecting changes in pressure. | More... |
| Lectotype | A name-bearing type designated from a syntype series. This is done if the syntypesconsist of more than one species and the identity of the species in question needsto be fixed. A lectotype has the same status as a holotype/neotype. The rest of the syntype seriesbecome paralectotypes and have no name-bearing status. | More... |
| Lentic | Of still inland waters. Examples: swamps, ponds and lakes. | More... |
| Lepidophage | A specialized feeding behaviour where a fish feeds exclusively on, or at least primarily, fish scales. | More... |
| Leucism | An animal with white pigmentation, but normal eye color. This animal is not a "true" Albino.Also see Amelanism, Axanthic and Xanthism. | More... |
| LFS | Abbreviation for Local Fish Store. | More... |
| Limnivore | Literally eating "mud-based" foods. Fish that feed on Aufwuchs or biofilm. Examples of Limnivores includeAncistrus, Baryancistrus, Chaetostoma and Hypostomus species. | More... |
| Lipbrooder | A fish that "sits" on fertilized eggs with its mouth as a form of parental care. A Lipbrooder willcarry the clutch of eggs with him until they are ready to hatch. Example: Loricaria spp. | More... |
| Lotic | Of running water. Examples: Rivers, streams and creeks. | More... |
| Lunate | Crescent-shaped. | More... |
| Lutino | An animal lacking black pigment. Yellow and red pigments are present. This animal has red eyes. Also see Albino , Leucism and Xanthism. | More... |
| Mandible | The lower jaw. | More... |
| Maxilla | The upper jaw. | More... |
| Maxillary Barbels | Barbels on the upper jaw. | More... |
| Melanin | Pigment (brown or black) found in skin or hair. | More... |
| Melanism | An overload of melanin causing an animal to become completely dark. | More... |
| Mental Barbels | Barbels on the chin. | More... |
| Meristics | Countable traits that can be used to describe a particular species of fish, or used to identify an unknown species. | More... |
| Metabolic Rate | The speed at which an organism converts food into energy and waste. | More... |
| Metabolism | The biochemical process in which an organism converts food into energy and waste. | More... |
| Milt | Fish sperm. | More... |
| Mimicry | The ability of a species to imitate another's behavior or appearance. Some species may imitate an inanimateobject, such as a leaf or a branch to blend in with the background and avoid predation. | More... |
| Monophyletic | Having a single common ancestor. | More... |
| Monotypic | Referring to a genus or family that contains a single species. | More... |
| Morph | A variation or a different form. Example: longer fins or a different color on the same species. | More... |
| Morphology | The scientific study of the structure and form of organisms. | More... |
| Mouthbrooder | A fish that carries the eggs and sometimes the larvae in its mouth. The eggs may be carried by the femaleor the male, depending on the species. Phyllonemus typus from Lake Tanganyika is uniques among catfishes in thatthe parents share Mouthbrooding responsibilities. With Arius graeffei from the South Pacific, the malecan carry up to 120 eggs in his mouth for 6 to 8 weeks. | More... |
| Mucus | A protective layer that functions to protect against infectious agents such as fungi, bacteria and viruses. | More... |
| Mullerian mimicry | Similar bright colors or patterns being used as a warning system between unrelated dangerous or noxious animals. | More... |
| Mulm | Fish wastes and other solid matter that accumulates in the aquarium. | More... |
| Naked | Referring to a fish without scales. | More... |
| Nape | The area on the back between the head and the dorsal fin. | More... |
| Nasal Barbels | Barbels on the nose. | More... |
| Native | Describing a species that occurs naturally in a particular area. | More... |
| Necropsy | Autopsy performed on an animal. | More... |
| Necrosis | The death of cells in a part of the body. | More... |
| Neoteny | A condition where juvenile characteristics extend into adulthood. | More... |
| Neotype | A name-bearing designation subsequent to the original description. Neotypes have the same statusas holotypes, and are designated to replace holotypes when they are lost and the identity ofthe species in question is in doubt. | More... |
| Neutral | Water which has a pH of 7.0 at a temperature of 20° Celsius. The point where the concentrationof an acid and an alkali are equal. | More... |
| Nitrate | NO3 ions. Nitrate is the "final" stage of waste breakdown in water. It is mildly poisonousto fish but some will survive in water with levels as high as 100 ppm,although this is not recommended. (See Nitrogen cycle) | More... |
| Nitrite | NO2 ions. Nitrite is VERY poisonous to fish since it prevents oxygen uptake, among other things. Afterammonia is broken down in the aquarium by "good bacteria," Nitrite is the byproduct(see ammonia).Nitrite can also be broken down further by "good bacteria." | More... |
| Nitrogen cycle | The process where the fish waste in form of ammonia is converted to nitrite and then nitrate. This process takes place in the filter, with the help of beneficial bacteria. | More... |
| Nocturnal | Happening during the night or nightly. | More... |
| Nomenclature | The system of scientifically naming plants and animals. | More... |
| Nominal Taxa | A taxon which is denoted by an available name. Example: Homo Sapien. | More... |
| Nuchal | Of the nape. | More... |
| Nuchal Shield | A bony plate between the back of the head and the dorsal fin. | More... |
| Obligate | Forced to do something to stay alive, i.e. obligate parasite cannot survive without a host. | More... |
| Ocellus | Colored marking on a fish that resembles an eye, plural is ocelli. | More... |
| Odontodes | Bristlelike structures on the surface of certain catfishes. | More... |
| Offsite Resources | Places other than Planet Catfish with useful information on a certain species. | More... |
| Olfactory | Relating to the sense of smell. | More... |
| Omnivore | A species which will eat both vegetable and meat based foods. | More... |
| Ontogeny | The entire sequence of events involved in the development of an individual organism. | More... |
| Oocyte | An egg cell. | More... |
| Oophagy | The eating of eggs, usually (but not necessarily) as a major portion of an animal's diet. | More... |
| Opercular spine | Spine projecting from the operculum (gill cover). | More... |
| Operculum | A bony flap located behind the head, on each side of the body, which protects the gills. | More... |
| Organic | A chemical compound which is carbon-hydrogen based. | More... |
| Osmoregulation | An organism's ability to maintain the proper balance of water and salts. | More... |
| Osmotic Pressure | The force that moves water across a semi-permeable membrane. | More... |
| Osteology | The study of the structure and development of bones. | More... |
| Ostracoda | A class of small crustaceans usually less than 1 millimeter in length. Also called seed shrimp. | More... |
| Other Parameters | Also see General Remarks. May include water hardness, conductivity, water movement, seasonal variations andwater specific husbandry difficulties. | More... |
| Otophysans | This group comprises much of the world's Freshwater fish diversity and includes carps, loaches,characins, electric (knife) fishes and catfishes. Also see Weberian Apparatus. | More... |
| Outcrossing | Adding new blood from an unrelated source. Outcrossing is used in conjunction with other inbreeding practices toto try to reduce the problems associated with less genetic diversity. | More... |
| Oviparous | A fish which lays eggs that are fertilized, develop and hatch outside the body. | More... |
| Oxbow | A "U"-shaped lake that occurs when a section of river, stream or tributary is cutoff from the main section and isolated. Also applies to a type of river thathas many "U"-shaped meanders in its course. | More... |
| Paedomorphism | The retention of juvenile characteristics into adulthood | More... |
| Paired Fins | A term used to indicate the fins that come in pairs on a fish, i.e. the pectoral and ventral fins. | More... |
| Parasite | Organism that is living in another with no benefit to its host and is dependant on this host for survival. | More... |
| Paratype | Additional specimens used in the original description of a species. Strictly speaking, a paratype hasno name-bearing status (and is no different from any other specimen of that species). | More... |
| Parthenogenetic | A fish that reproduces without fertilization, the sperm induces development of the egg but there is no exchange of genes. | More... |
| Parturation | Giving birth. | More... |
| Pathogen | Virus, bateria or other microorganism that causes disease or illness to its host. | More... |
| Pathognomonic | Characteristic or diagnostic of a specific disease. | More... |
| Pectoral | Of the chest. | More... |
| Pectoral Girdle | A set of bones which supports the pectoral fin. | More... |
| Pelagic | Living at the middle and/or upper levels or a lake, river or ocean. | More... |
| Pelvic | Of the pelvis or hip area. | More... |
| Periphyton | Microscopic plants and animals which attach and grow on substrate. Also see Aufwuchs. | More... |
| pH | Literally pondus Hydrogeni. The measure of a liquid's acidity or alkalinity. pH is measured from 0.0 (very acidic) to 14.0(very alkaline) with 7.0 being neutral. This measurement is logarithmic, meaning any change is significant. A suddenchange in pH will cause a great deal of stress, or may even lead to the death of a fish. | More... |
| pH Crash | Rapid lowering of pH in an aquarium due to lack of buffering capacity (see Hardness). | More... |
| Phenotype | The charactaristics of an organism based on genetic inheritance. Examples: In humans, eye-colour (blue or brown).In fish, long fins or short fins. | More... |
| Photoperiod | The amount of light in a day, either natural or artificial. | More... |
| Phototaxis | The movement of an organism or a cell toward or away from a source of light. | More... |
| Pigmentation | The substance that gives a plant or animal its color. | More... |
| Pinnate | Feather-like. | More... |
| Piscivore | A species which eats exclusively or, at least primarily, fish. | More... |
| Planaria | A flatworm that often sets up residence in an aquarium and is considered a nuisance. | More... |
| Pore | An anatomical structure-a very small opening on the surface of the skin | More... |
| Posterior | Toward the rear. | More... |
| Potamodromous | Fish who migrate completely in freshwater to spawn. | More... |
| PPB | Parts Per Billion. | More... |
| PPM | Parts Per Million. | More... |
| PPT | Parts Per Thousand. | More... |
| Predator | An animal that survives by capturing and eating other animals. | More... |
| Pronunciation | The correct way to say a word. | More... |
| Protrusible | A mouth that can be extended. Some catfishes have a Protrusible mouth to catch prey. | More... |
| Proximal | Toward a point of reference, usually the center of the body. Opposite: distal. | More... |
| Psammophile | A sand-loving organism | More... |
| Psammophilous | The ability to inhabit sandy areas. | More... |
| Quarantine | Compulsory isolation, typically to contain the spread of something considered dangerous. | More... |
| Ray | A rod-like support structure for the fin. | More... |
| RCD | Residual Current Device, a device that protects humans from current by isolating (breaking) the circuit, when there is a fault in the electrical circuit. See also GFCI. | More... |
| Reference | Where the original description of the species was published. With this, a (scientific/university) library can find theoriginal discription. May also contain further reading on points raised in the page. | More... |
| Registered Keeper | The "My Cats" registered keeper facility allows members of the forum to register that they own a particular species, and record how they are keeping the fish. | More... |
| Respiration | Process of passing gaseous nutrients to the blood. | More... |
| Reticulate | Forming a mesh-like pattern. | More... |
| Reverse Osmosis | Also called RO Filtration. A method of filtration where the water is forced across a semi-permeablemembrane. The most common type of membrane is made of Thin Composite Film (TFC). Thismethod is between 94-99% effective in laboratory conditions. Cellulose Tri-Acetate (CTA) membranes are lesseffective and less common. Low water pressure and exceedingly poor water quality will reduce thelifespan of an RO membrane. The typical layout of a filter is a 1 or 5 micron pre-filter, followedby a carbon block pre-filter and then the RO membrane. | More... |
| Revision | (Taxonomy) To re-examine a species, genus or family to correct mistakes/inconsistancies and possiblymake changes to the status of described taxa. | More... |
| Rheophilic | Species that love moving water. | More... |
| Rheotaxis | Response of an organism to face towards or sometimes away from a current of water. | More... |
| Rictal Barbels | Barbels extending from the corner of the mouth. | More... |
| Rictus | The corner of the mouth. | More... |
| Riffle | A rocky part of a stream with fast-moving water. | More... |
| Rift Lake | A lake formed by volcanic activity which produces a split in the landscape. Over time, thisis then filled by rainwater and/or rivers producing a lake. Fish from Rift LakesTanganyika, Malawi and Victoria in Africa are commonly imported. | More... |
| Riverine | Of rivers. | More... |
| Rostrum | Snout. | More... |
| Rugose | Rough or wrinkled. | More... |
| Saddle | A patch of color that starts at the midline of the body and extends down the sides. | More... |
| Salinity | A measure of dissolved salts in water. | More... |
| School | Generally the same as schoal, but it is sometimes used to mean a closer shoal where all the fish havethe same orientation. Example: the fish forming patterns in the Disney/Pixar feature film Finding Nemo.Also more often associated with Marine fish rather than Freshwater varieties. | More... |
| Scientific Name | Latin-based nomenclature used by scientists to identify a species. A species may only have oneScientific Name to eliminate confusion. | More... |
| Scutes | Bony plates on the surface of the skin. Unlike scales, scutes cannot be easily removed from the skin. | More... |
| Seine | A net used to encircle fish. | More... |
| Semilunar | Half-moon shaped. Also see Lunate. | More... |
| Senior Synonym | The earlier established of two or more synonyms. A Senior Synonym has priority over a Junior Synonym. | More... |
| Serrae | A row of small spines or recurved points along the pectoral or dorsal spine. | More... |
| Sessile | To be attached at the base. Also, a fish that is sedentary. | More... |
| Sexing | How to differentiate a male from a female of a certain species. | More... |
| Shoal | A group of fish, usually all of the same species, that swim together as a group. | More... |
| Size | The likely maximum length of a fish in SL. Normally, this is the largest formally recorded size of an individual, where data is less available, this is based on the largest seen. See Standard Length and Total Length. | More... |
| Snout | The nose area. Also see Rostrum. | More... |
| sp. | Abbreviation of Species in singular form (so only one species). | More... |
| Spawning | Eggs and sperm released or deposited, usually into water, by aquatic animals. | More... |
| Species | Basic unit of classification in taxonomy. One or more species that are considered to have the same evolutionary ancestor are grouped in the same Genus. | More... |
| Speciose | Usually referring to a family or genus that has a large number of species. | More... |
| Spine | A hard ray. | More... |
| Spinelet | A locking mechanism found at the base of the Dorsal Spine. It holds the Dorsal Fin erect. | More... |
| spp. | Plural of sp. Example: There are more than one dozen described Panaque spp. | More... |
| Standard Length | Abbr. SL The distance from the tip of the snout to the base of the tail. To put it another way, the length of the fish excluding the caudal fin. | More... |
| Strip | The removal of eggs and sperm for artificial breeding also to remove eggs or young from the buccal cavity of mouthbrooding fish. | More... |
| Sub-Adult | A young fish similar in appearance to an adult, but not yet capable of reproducing. | More... |
| Subcutaneous | Beneath the skin. | More... |
| Substrate | Material used to cover the aquarium floor. Examples: gravel or sand. | More... |
| Subterminal | A mouth position between inferior and terminal. A lot of catfishes have Subterminal mouths. | More... |
| Superior | Directed upwards. In Icthyology, also refers to a mouth that is directed upwards. | More... |
| Supraoccipital | The median bone at the upper end of the cranium. | More... |
| Symbiotic | A mutually beneficial relationship between two different organisms. | More... |
| Sympatric | A situation in which two or more species live in the same general habitat but may not coexist together. (See also Syntopic). | More... |
| Synonym | In general, another name for the same thing. In zoology, each of two (or more) different names forthe same taxon or taxonomic entity. | More... |
| Syntopic | A situation in which two or more species co-exist in the same habitat at the same time. (See also Sympatric). | More... |
| Syntype | Multiple specimens designated as name-bearing types. Each syntype has equal status as a name-bearingtype as its fellow syntypes. | More... |
| T-Position | The manner in which some Corydoradine catfishes breed. So named because the breeding pair look as ifthey are forming the letter "T." Also see More... | |
| Tankbuster | A fish that grows too large for the average home aquarium. | More... |
| Tautonomy | A taxonomic designation, such as Hara hara, in which the genus and species names are the same, commonly used in zoology but no longer in botany. | More... |
| Taxon | A group or groups of populations that are related. A Taxon has charactaristics which separate it fromother populations. Plural: Taxa | More... |
| Taxonomy | The theory and practice of classifying organisms. | More... |
| TDS | Total Dissolved Solids. A way to calculate water quality by measuring organic and inorganicsubstances present. Total Dissolved Solids may be measured in the laboratory or, moreconveniently, by electronic meter, using mg/l(milligrams per liter). Similar to Conductivity. | More... |
| Teleost | A bony fish. | More... |
| Temperature | The range of warmth a species can tolerate, noted in both degrees Celsius and Fahrenheit. | More... |
| Terminal | Literally an end. In Icthyology, also refers to a mouth directed forwards, i.e. at the tip of the Snout (rostrum). | More... |
| Topotype | Specimens collected from the type locality (where the holotype/syntypes were collected) subsequent tothe original description. Topotypes have no name-bearing status (although they are useful as potential neotypesshould the holotype be lost.) | More... |
| Total Length | Abbr. TL The distance from the tip of the snout to the tip of the tail. | More... |
| Toxin | Poisonous substance produced by living cells or organisms. | More... |
| Troglobitic | A reference to any creature having a cave-dwelling mode of life. | More... |
| Troglomorphic | Morphological characters that are adaptions to living in the constant darkness of caves. | More... |
| Trophic Level | A stage in the food chain a species occupies. Example: A big fish eats the small fish, which in turneats an even smaller fish. | More... |
| Truncate | With a straight edge; square cut. | More... |
| Tubercules | Small skin growths that appear on the head and sometimes body of sexually mature fish,normally the male. | More... |
| Tubifex | Tubificid worms may be used as fish food. They may be fed freeze-dried, frozen or live.Care must be taken when feeding live Tubifex Worms as they are notorious for carrying disease. If too many arereleased into the aquarium, they will establish themselves in the substrate and detrimentally impact water quality. | More... |
| Turbid | Water clouded by suspended particulate matter. | More... |
| Type Locality | The place where the Holotype specimen used to describe a species was found. | More... |
| Ventral | Of the underside. | More... |
| Ventral Fin Basket | A clamping of the ventral fins by the female of some Corydoradine catfishes so that she may carryfertilized eggs. Also see T-Position. | More... |
| Vermiculation | A wavy, worm-like or network pattern. | More... |
| Villiform Teeth | Fine, long teeth that are crowded together. This gives the appearance of a patch of velvet. | More... |
| Vomer | The bone on the palate, i.e. the "roof of the mouth." | More... |
| Weberian Apparatus | The modified first four or five vertebrae that connect the dorsal wall of the swimbladderto the inner ear. This increases sensitivity to sound. The Weberian Apparatus is present in agroup called Otophysi. | More... |
| Xanthism | An animal which is yellow or golden in color. This may happen in nature or through selective breeding. | More... |
| Xylophagy | A term used in ecology to describe the habits of an herbivorous animal whose diet consists primarily (often solely) of wood. | More... |
| Yolk Sac | A pouch containing nutrients for a newly hatched larva. | More... |
| Zoonosis | A disease which can be transmitted from an animal to a human. | More... |
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