frenum
A connecting or restraining membrane, such as that connecting the tongue to the base of the mouth.
Used in 17 profiles
Ichthyological terms, not general ones.
A connecting or restraining membrane, such as that connecting the tongue to the base of the mouth.
Used in 17 profiles
Method of differentiating bacterial species into groups based on the structure of their cell walls, using a particular, violet-coloured, staining technique.
Bony process extending posteriorly from the pectoral girdle, above the base of the pectoral fin. Present only in certain fishes.
Used in 8 profiles
Ridgelike structure located on the ventral surface, caudal peduncle or caudal fin base in certain fishes.
Used in 35 profiles
SI base unit of thermodynamic temperature, equal in magnitude to the degree Celsius.
Used in 5 profiles
Bony process or plate at the base of the first ( unbranched ) and second ( first branched ) ray of the pectoral-fin in most male specimens of the family Cobitidae. It is also known as 'Canestrini's scale'.
Used in 24 profiles
The number of more-or-less vertically-arranged scale rows present between the upper end of the gill opening and the caudal fin base. Sometimes referred to as vertical scale rows and used in meristic counts when the lateral line is absent, incompletely pored or otherwise difficult to distinguish.
Used in 9 profiles
Located or orientated on the side towards the base or bottom.
Used in 1 profile
Physical character based on measurement, e.g. standard length.
Used in 5 profiles
Branch of taxonomy concerned with the application of scientific names to taxa, based on a particular classification scheme and in accordance with agreed international rules and conventions.
Used in 5 profiles
A nomenclatural concept denoted by an available name used in an original description, and based, actually or potentially, upon its name-bearing type but having no defined taxonomic boundaries. Often used when the precise definition of a species or genus is unclear, such as when a name may refer to more than one taxon and is therefore in need of clarification.
Used in 33 profiles
Elongate bone located in the base of the skull in many vertebrate organisms.
Used in 7 profiles
In zoological nomenclature, a specimen other than the holotype upon which a description is based, i.e., each specimen of a type series other than the holotype.
Used in 9 profiles
Species concept based on the evolutionary relationships among organisms, specifically using common ancestry and shared evolutionary history to define species. Under this concept a species is essentially the smallest group of organisms that share a common ancestor and can be distinguished from other such groups via phylogenetic analyses. Each such grouping constitutes a distinct branch on an evolutionary tree. Subspecies tend not to be recognised and it is generally less restrictive than the biological species concept. Often abbreviated to PSC.
Used in 1 profile
The study of evolutionary relatedness among species or other groups of organisms. May be based on morphology, molecular data, or both.
Used in 3 profiles
The evolutionary development and history of a species or other taxonomic group. May be based on morphology, molecular data, or both.
Used in 52 profiles
In cladistics, a character or trait shared by two or more taxonomic groups but derived from a remote or much earlier common ancestral form and therefore cannot be used to define a clade. Also known as an ancestral state and generally appears at the base level of a cladogram.
Used in 2 profiles
The distance between the dorsal fin insertion/origin and caudal fin base.
Used in 2 profiles
Form of niche differentiation by which two species partition (divide) a resource based on behavioral or morphological variation in order to ensure their mutual survival by reducing competition.
Used in 11 profiles
Wedge-shaped; a bone at the base of the skull; of or relating to the sphenoid bone.