Glossary of Terms Used Within This Web Site

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aff. affinis, to species you know are distinct, but closely related.
Allotype* A term, not regulated by the Code, for a designated specimen of opposite sex to the holotype.
Anal Fin The median, unpaired, ventrally located fin that lies behind the anus, usually on the posterior half of the fish. (126) See chart for details.
Benthopelagic Living and feeding near the bottom as well as in midwaters or near the surface. Feeding on benthic as well as free swimming organisms. Many freshwater fish are opportunistic feeders that forage on the bottom as well as in midwater and near the surface
Benthic Dwelling on, or relating to, the bottom of a body of water; living on the bottom of the ocean and feeding on benthic organisms
Biotope An area of relatively uniform environmental conditions, occupied by a given plant community and its associated animal community. ~ EUNIS
Body Depth This measurement usually taken as the greatest distance from the dorsal midline to the ventral midline of the body (greatest depth of body). However, in some works this depth is measured at the origin of pectoral fins, pelvic fins and first anal fin. (126) See chart for details.
Caudal Fin Often called the tail fin, it provides the main power for forward movement in fish. It may be square or slightly indented to deeply forked. (126) See chart for details.
Caudal Peduncle The narrow part of the body between the posterior ends of the dorsal and anal fins and the base of the caudal fin. (126) See chart for details.
cf. confer, to species you supose to be same.
Cotype* A term not recognized by the Code, formerly used for either syntype or paratype, but that should not now be used in zoological nomenclature.
Dorsal Fin A median fin along the back which is supported by rays. There may be two or more dorsal fins, in which case the most anterior one is designated the first. (126) See chart for details.
Fin Rays The supporting bony elements of fins, including spines and soft rays; all fin-supports are rays, whether segmented, unsegmented or spinous, but sometimes the term ray is used to denote soft rays only. (126) See chart for details.
Genotype* A term not recognized by the Code, formerly used for type species, but that should not now be used in zoological nomenclature.
Head Specialized anterior part of an animal on which the mouth and major sensory organs are located; part other than the body (snout to the posterior gill opening in fish). (126) See chart for details.
Holotype* A single specimen designated as the name-bearing type of a species or subspecies when it was established, or the single specimen on which such a taxon was based when no type was specified.
Lateral Line The lateral line consists of a series of scales, each modified by a pore, which connects with a system of canals containing sensory cells and nerve fibers. It runs in a semi line from the gills to the tail fin. It can easily seen in fish as a band of darker looking scales running along the side. The Lateral line has shown to be a very important sensory organ in fish. It can detect minute electrical currents in the aquarium water. It can also function as a kind of echo location process that helps the fish identify its surroundings. (130) See chart for details.
Lectotype* A syntype designated as the single name-bearing type specimen subsequent to the establishment of a nominal species or subspecies.
Morphometric Measurement of external forms. See chart for details.
Name-bearing type* The type genus, type species, holotype, lectotype, series of syntypes (which, together, form the name-bearing type), neotype, type slide, or hapantotype, that provides the objective standard of reference whereby the application of the name of a taxon can be determined.
Nape The part of the back that extends from the margin of the skull to the dorsal-fin origin; also, the region of the head above and behind the eyes. (126) See chart for details.
Neotype* The single specimen designated as the name-bearing type of a nominal species or subspecies for which no holotype, or lectotype, or syntype(s), or prior neotype, is believed to exist.
New combination When a species is transferred to a different genus for the first time
Nomen nudum A name that does not fulfill the criteria set by the International Code of Zoological Nomenclature as a legally described scientific name and therefore cannot be used unless it is subsequently proposed correctly
Operculum Bony gill cover; comprised of four bones: opercle, preopercle, interopercle and subopercle. (126) See chart for details.
Paralectotype* Each specimen of a former syntype series remaining after the designation of a lectotype.
Paratype* Each specimen of a type series other than the holotype.
Pectoral Fins The fin usually found on each side of the body behind the gill opening; this pair of fins is found on the lower parts of the body in primitive forms of fish; corresponding to the forelimbs of higher vertebrates; united to form the disc in most rays. (126) See chart for details.
Pelvic Fins See Ventral Fins.
Soft Ray A segmented fin ray which is composed of two closely joined lateral elements. It is nearly always flexible and often branched. (126)
Snout The part of the head in front of the eye; the distance from the eye to the anterior tip of the head above the upper jaw (normally the upper lip). (126) See chart for details.
Spine A sharp projecting point; if referring to fins, a stiff unsegmented, undivided and unbranched element supporting a fin. (126)
Standard Length (SL) The length of a fish from the front of the upper lip to the posterior end of the vertebral column (the last element has a broadened hypural plate forming the bony support for the caudal fin rays). In small dead fish, the end point is detected by bending the caudal fin to one side. In fishery work, as a result of the use of the measuring board, standard-, fork- and total length are taken from the most anterior part of the head. (126) See chart for details.
Synonymy A section of a systematic presentation about an organism that lists all of the names that have been used for the organism including
synonyms, new combinations, misidentifications, etc. In some cases this section may include only true synonyms
Syntype* Each specimen of a type series from which neither a holotype nor a lectotype has been designated.
Topotype* A term, not regulated by the Code, for a specimen originating from the type locality of the species or subspecies to which it is thought to belong, whether or not the specimen is part of the type series.
Total Length (TL) The length of a fish measured from the front of the jaw which is most anterior to the end of the longest caudal ray when the rays are squeezed together, but excluding the caudal filaments. (126) See chart for details.
Type* A term used alone, or forming part of a compound term, to denote a particular kind of specimen or taxon.
Type horizon* The geological stratum from which the name-bearing type of a nominal species or subspecies was collected.
Type locality* The geographical place of capture or collection of the name-bearing type of a nominal species or subspecies. If the name-bearing type was captured or collected after being transported by boat, vehicle, aircraft, or other human or mechanical means, the type locality is the place from which it, or its wild progenitor, began its unnatural journey.
Type series* The series of specimens that either constitutes the name-bearing type (syntypes) of a nominal species or subspecies or from which the name-bearing type has been or may be designated.
Type species A species that has been selected as the standard bearer of a genus or subgenus
Type specimen* A term used in previous editions of the Code for holotype, lectotype, or neotype; also used generally for any specimen of the type series.
Type genus A genus that has been selected as the standard bearer of a tribe, family, or superfamily and provides the stem of the family-group
Ventral Toward the lower part of the body; on or towards the lower surface (the underside) of the fish; the opposite of dorsal. (126) See chart for details
Ventral Fins Pair of fins corresponding to the hind limbs of higher vertebrates; these vary in position from well behind the pectoral-fin base, to below it, to distinctly before it, their progression forward in general paralleling the advancement of their bearers up the evolutionary ladder to more specialized levels. (126) See chart for details.

* From International Code of Zoological Nomenclature