Glossary
Terminology Description
Terminology Description
Abdomen Belly
Abdominal Pertaining to the belly
Absolute abundance Absolute abundance is the total number of a kind of fish in the population. This is rarely known, but usually estimated from relative abundance, although other methods may be used
Absolute recruitment The number of fish grow into the catchable size range in a unit of time (usually a year)
Actinosts A series of bones at the base of the pectoral rays
Acuminate Tapering gradually to a point
Acute Sharp, pointed
Adelphophagous A mode of feeding where an embryo feeds on other embryos within the uterus of the female
Adipose Fatty
Adipose fin A small fleshy fin which lacks fin rays
Adnate Joined together
Adpressed Pressed against the body
Aestivate To be inactive during warm dry periods
Airbladder Buoyancy organ possessed by most bony fishes and also called as swim bladder
Alimentary canal The passage through which food passes, starting at the mouth and ending at the anus
Anal Pertaining to the anus
Anal fin The fin on the median line behind the vent
Anal fin origin The most anterior point of the anal fin base
Ankylosed Grown firmly together
Anterior Relating to the front portion
Antrose Turned forward
Anus The external opening of the intestine, the vent
Artisan Someone who practices a craft as a livelihood
Artisan fishing A small scale commercial or subsistence fishing practices
Asperity Roughness of surface
Asymetrical Without symmetry
Attenuate Tapering to a point
Axillary Process an enlarged, pointed scale projecting from the insertion of the pectoral or pelvic fin
Bait fish Are small fish caught for use as bait to attract large predatory fishes
Barbels Fleshy whisker like extensions, usually under the mouth
Basal Pertaining to the base
Biconcave tail Outer and inner fin rays longer giving a double concave shape (same as double emarginated)
Bicuspid Having two cusps or points
Bifid Cleft in two
Bifurcate Forked or divided into two parts or branches
Blotch Pigmented spot with an indistinct outline or shape
Branchial Pertaining to the gills
Branchial aperture The gill opening
Fish Branchiostegals, Branchiostegal ray(s) Bony rays supporting the gill membranes behind the lower jaw
Bristle A stiff hair like projection
Buckler A bony shield
Bycatch Species other than the target species that are caught incidentally in a trawl
Canines Conical teeth which are longer than other teeth
Caniniform shaped Like a canine tooth, conical in form
Carapace A horny or bony covering encasing the body
Carinate Keeled, having a ridge along the middle line
Caruncle A fleshy outgrowth
Catadromous "Catadromous" species, spawn in the ocean but live part of their lives in fresh water
Caudal Pertaining to the tail
Caudal fin The tail fin
Caudal peduncle Region of the body between end of anal fin and base of caudal fin
Choroid fissure Line of juncture of invaginating borders of the optic cup
Choroid tissue An undifferentiated mass of unpigmented tissue adhering to the ventral surface of the eye
Chromatophore A modified dermal cell that contains pigment and gives the fish its colour
Ciliated Fringed with eyelash like projections
Cirri Small, thin appendages often subdivided into branches
Cleithrum A prominent bone of pectoral girdle
Coalesced Grown together
Cohort Those individuals of a stock born in the same spawning season
Compressed Flattened laterally
Confluent Joined together
Conical Cone shaped, with a cylindrical base and a pointed tip
Corselet A scaly covering behind the pectorals of some fishes
Countershading body Colouration which is dark above and lighter below
Crenulate Having the edge slightly scalloped
Ctenoid Rough edged
Cusp A pointed or rounded projection on the chewing surface of a tooth
Cutaneous Pertaining to the skin
Cycloid Smooth edged
Deciduous Easily removed / rubbed off, temporary, falling off
Demersal Living on or near the sea bed
Demersal egg An egg which remains on the bottom either free or attached to the substratum
Dendritic Resembling a tree or shrub
Dentate With tooth like projections
Depressed Flattened from top to bottom
Dermal Pertaining to the skin
Dewlap A fold of loose skin
Diadromous Species which undertakes spawning migration from ocean to river or vice versa.
Dimorphic Body shape and colour varies between the sexes
Disc The flattened head and body of fishes
Distal Remote from the point of attachment
Dorsal Pertaining to the back
Dorsal fin Fin on dorsal side
Dorsal fin origin Anterior most point of the dorsal fin base
Dorsum The upper surface of the head or body
Egg survey A systematic and scientific estimation of the abundance of eggs in an area, through sampling at the bottom or in the water column with appropriate devices
Electrocyte A cell that generates electricity
Elongate Extended, drawn out
Emarginate With the margin slightly hollowed
Endemic Restricted to a particular region
Epibenthic Referring to organisms living on the bottom surface
Epipelagic Referring to organisms living in the region between surface and 200 m depth
Erectile Capable of being raised or erected, often referring to spines
Esca The lure or "bait" on the end of the illicium of some anglerfishes and relatives
Estuarine Living in estuaries
Eye diameter (ED) Horizontal distance across the midline of pigmented region of the eye
Falcate Scythe shaped, long, narrow and curved
Falcate tail Tail fin shaped like a sickle, deeply concave, with the middle rays much shorter than the anterior or posterior rays
Falciform Curved like a scythe
Fecundity The number of eggs a fish produces each reproductive cycle
Filament A slender or thread like structure
Filiform Thread like
Fimbriate Fringed at the margin
Fin length Length of the longest soft ray of designated fin
Finfold Medial fold of integument that extends along body of developing fishes and from which medial fins arise
Finlet A small fin, positioned behind the dorsal or anal fins, that is supported by a ray or rays
Fishery Fishery is characterised by the species caught, the fishing gear used and the area of operation. It may involve capture of wild fish or rising of fish through aquaculture
Fishing fleet An aggregation of fishing vessels of a particular country or particular gear
Fishing vessel a vessel (provide assistance to other fishing vessels such as supply, storage, refrigeration, transportation or processing) normally used for harvesting living aquatic resources
Fishmeal A fish based protein rich animal feed product
Fleshy tail Tail with fleshy knob
Flexion Bending upward of the notochord tip as part of the process of caudal fin formation
Flexion larva Development stage beginning with flexion of notochord and ending with hypural bones assuming a vertical position
Fluviatile Living in rivers
Fork length The length of a fish as measured from the tip of the snout to the fork of the caudal fin
Free rear tips (of fins) The posterior tip of fin closest to the most posterior point of fin base
Frontal ridge A ridge running along the top of the head along the midline
Furcate Forked
Fusiform Tapering towards both ends
Gametes Eggs and sperm
Gas bladder Membranous, gas filled organ located between the kidneys and alimentary canal in teleost fishes
Gill arches The bony arches in which gills are attached
Gill cover Bony flap that covers the gills, the operculum
Gill filaments A series of projections along the posterior edge of the gill arch, the site of gas exchange
Gill membranes Membranes covering the gill openings, attached to the branchiostegals
Gill opening Opening behind each operculum, leading to the gills
Gill rakers A series of appendages along the anterior edges of the gill arches
Gill Organs for breathing the air contained in water
Glossohyal Tongue bone of fish
Gonads Sexual organs which produces eggs or sperm
Gonopodium Modification of anal fin in some male fishes used to transfer reproductive products to the female
Gravid Sexually ripe
Gular Region behind the chin and between the sides of lower jaw
Head length (HL) Distance from snout tip to the most posterior point of opercular margin
Head width Transverse distance between margins at the widest area of the head
Homology Similarity of features based on common evolutionary descent
Hyaline Translucent or transparent
Hyperostosis A condition resulting in enlargement of areas of bone
Hypural Joint the joint between the caudal fin and the last of the vertebrae
Hypural plate The flattened bony plate at the posterior end of the vertebral column, formed from parts of the posterior vertebrae
Ichthyocide A substance used to kill (and usually collect) fishes
Ichthyoplankton Fish eggs and larvae floating on the surface of water
Illicium A fishing rod like appendage on the head of frog fish
Imbricate Overlapping
Incipient fin ray Early stage in fin ray development (unossified thickening in finfold articulating with the fin base)
Incised With a notched margin (often referring to fin membranes)
Incisors The front or cutting teeth
Inferior Pertaining to the lower side (usually of the head)
Interdorsal Between the dorsal fins
Interorbital The space between the orbits
Intromittent A structure to facilitate sperm transfer in some internally fertilizing species
Iris lappet A fleshy flap or lobe like structure in the eye (may be short and rounded, simple or multiply branched)
Isthmus The fleshy projection of the body separating the gill openings
Jugostegalia Basket like structure of over lapping free branchiostegal rays used as support for the extended branchial region in some eels.
Jugular Pertaining to the throat
Juvenile Developmental stage from attainment of full external meristic complements and loss of temporary specializations for pelagic life to sexual maturity
Juxtaposed Placed near together
Labial Pertaining to the lips
Labial furrows Shallow grooves around the lips
Labial papillae Small fleshy projections around the lips
Lacrymal, lachrymal Anterior bone of infraorbital series (frequently overlaps the maxilla when the mouth is closed)
Lanceolate Spear shaped, gradually tapering toward the extremity
Larva Developmental stage between hatching (or birth) and attainment of full external meristic complements (fins and scales) and loss of temporary specializations for pelagic life
Larval teeth A little exerted spines on the premaxilla or dentary
Lateral At or toward the side
Lateral line A series of muciferous tubes forming a raised line along the side of body
Longitudinal series (scales) The number of scale rows above the lateral line from the first pored lateral line scale to the caudal fin base
Lunate Shaped like a crescent moon, with long upper and lower lobes
Lyosphaera stage A specialized pelagic juvenile stage in the genus Chilomycterus, where elongate papillae develop but these fail to form spines.
Mandible The lower jaw
Maxilla, Maxillary The upper jaw
Median fins Fins located on the median line of the fish (dorsal, anal and caudal fins)
Mediolateral Between the middle and the sides
Melanin A black pigment
Melanophores Melanin bearing cells (frequently capable of expansions and contractions which change their size and shape)
Mesocoracoid A bone of the pectoral arch or shoulder girdle
Mesopelagic Fishes that live in the mesopelagic zone
Midwater fishes Fishes that live in the midwater (well below the surface and well above the seabed)
Molars Blunt and rounded grinding teeth
Morphology Form and structure of an organism
Mouthwidth The gape transverse distance between corners of the mouth
Muciferous Producing or containing mucous or slime
Myosepta Connective tissue partitions separating adjacent myomeres
Myotomes Serial muscle bundles of the body
Nape Upper surface of the body behind the head and before the dorsal fin
Nasal Pertaining to the nostrils
Nasoral Between the nostrils and mouth
Nictitating membrane An inner eyelid
Notochord Longitudinal supporting axis of body which is eventually replaced as a support by the vertebral column in teleostean fishes
Notochord length Straight line distance from tip of snout to posterior tip of notochord
Nuchal Pertaining to the nape
Obsolete Faintly marked, scarcely evident
Obtuse Blunt
Occipital Pertaining to the posterior part of the skull
Ocellus An eye like spot
Ocular Pertaining to the eye
Oesophagus The gullet
Olfactory organs The organs used for smelling, commonly beneath the nostrils
Olfactory pit A shallow depression on the snout from which olfactory organ develops
Opercular Pertaining to the operculum
Opercular spine Spine projecting from the operculum
Opercule, operculum The bony flap that covers the gills
Orbit The eye socket
Osseus Bony
Ossicle A bony plate
Otic capsule Sensory anlage from which the ear develops
Otolith Calcareous structures in the ear capsules of bony fishes
Ovate Egg shaped
Oviparous Species that produces eggs hatched outside of the body
Palate Roof of the mouth
Palatines Bones on each side of the palate Papilla (papillae) a small fleshy projection(s)
Papillose Covered with papillae
Pectoral Pertaining to the breast
Pectoral bud Swelling at site of future pectoral fin
Pectoral fins The anterior or uppermost of the paired fins
Pectoral girdle The bones to which the pectoral fin attached
Pelagic Living on or in the open seas
Pelagic egg Egg which floats freely in the water column
Pelagic juvenile Pre settlement juvenile of a species that is benthic or reef associated as an adult
Pelvic bud Swelling at site of future pelvic (ventral)
Pelvic fins Paired fins behind or below the pectoral fins
Pelvic girdle The bones to which the ventral fins are attached
Peritoneum The membrane lining the abdominal cavity
Pharyngeal bones Bones behind the gills in the oesophagus or gullet
Pharyngeal teeth Teeth within the pharynx
Pharynx The back part of the throat in which the gill slits open
Photophore A circular light producing organ on the surface of a fish
Piscivorous An organism that feeds upon fishes
Planktivore An animal with a diet that consists mainly of plankton
Postanal myomeres Myomeres posterior to the posterior margin of the anus
Posterior Towards the hind end of the fish
Postflexion larva Developmental stage from formation of the caudal fin to attainment of full external meristic complements and loss of temporary specializations for pelagic life
Postorbital Behind the eye
Pre dorsal fin length Distance from tip of snout along the midline to the origin of dorsal fin
Pre gas bladder length Distance from the tip of the snout along the midline to the anterior edge of gas bladder
Pre pelvic fin length Distance from the tip of snout along the midline to the origin of the pelvic fin
Preanal length (PAL) Distance from the tip of the snout along the midline to the posterior edge of the anus
Precaudal Anterior to the tail portion
Preflexion larva Developmental stage beginning at hatching and ending at the start of upward flexion of the notochord
Prehensile Adapted for holding such as the tail of a seahorse
Premaxillaries Two bones forming the front portion of the upper jaw
Preocular spine Spine positioned above and in front of the eye
Preopercle preoperculum Bone between the cheek and the gill cover
Preopercular spine Spine projecting from the preopercule
Preorbital Area under and in front of the eyes
Protractile Capable of extending forward
Protrusible Capable of extending forward often referring to the jaws of fishes
Proximal Nearest
Pseudobranchiae Small gills developed on the inner side of gill cover
Pseudoclasper Stiff ossified lobes or prongs in the tip of intromittent organ
Pterygiophore An internal cartilage or bone that supports a median fin ray or spine
Ramus One branch or one half of the jaw
Ray A jointed rod which supports a fin.
Retrose Turned backward
Rostrum A projecting snout or beak
Rugose Rough
Scalation Pertains to the pattern/ arrangement/ presence of scales
Scute Any external horny or bony plate
Serrate Notched like a saw
Setae Bristles or hairs
Sexual dimorphism Differences in physical appearance between the sexes
Snout length (SnL) Horizontal distance from the tip of snout to the anterior margin of pigmented region of the eye
Soft dorsal Posterior part of dorsal fin composed of jointed rays
Soft rays Bilaterally paired, usually segmented fin supports
Spatulate Shovel like having a broad, flat and rounded shape
Spawning The production or depositing of large quantities of eggs in water
Spine A sharp projecting point
Spine length Straight line distance of a fin or body spine from base to tip.
Spinous, spiniform, spinate Spine like or composed of spines
Spiracles Respiratory openings behind the eyes in sharks and rays
Standard length (SL) Length of a fish measured from the tip of snout to posterior extremity of hypural plate (the expanded bones at the end of the backbone that support the caudal fin)
Submarginal Almost at the edge
Suborbital Below the eye
Suborbital stay A bony, often spine bearing, ridge below the eye
Superior Above or on the upper surface
Supracleithrum Bone forming a connection between back of skull and pectoral girdle
Supralateral Above the side
Supramaxillary A supplemental bone lying along the upper edge of the maxillary
Supraocular Positioned above the eye
Supraorbital Above the eye
Supraorbital tentacle A flap or filament of skin positioned above the eye
Suprascapular A bone uniting the shoulder girdle with skull
Suture Line of union of two bones or plates
Swim bladder A sac filled with gas, lying beneath the backbone
Symbiosis Used to describe any association between two organisms
Symphysis Point of junction of two sides of the jaw
Symmetrical Similarly arranged on both sides
Tail The portion of body posterior to the anus.
Teleost A large group containing most of the bony fishes
Terminal At the end
Tessellated Marked with little checks or squares, like tiles
Thoracic Pertaining to the chest
Thorax Chest region, just behind the head
Total length (TL) Length from the tip of the snout to the tip of the tail
Transverse Crosswise
Tricuspid With three cusps or points
Trilobate With three lobes
Truncate Terminating abruptly, as if cut off square
Trunk Region between head and anus or between last gill slit and vent
Tubercle A small, usually hard excrescence or lump
Tubiform, Tubuliform Resembling a tube
Tympanum Area of enlarged scales behind the gill opening that can be vibrated to produce sound, in triggerfishes and filefishes
Undulated Waved uniform of one colour
Urogenital papilla A papilla through which urinary waste and gametes leave the body
Vent The external opening of alimentary canal, the anus
Vent to anal fin length Straight line distance from posterior edge of the vent (anus) to anterior origin of the anal fin or anal fin anlage
Ventral Pertaining to the abdominal or lower surface
Ventral fins Paired fins behind or below the pectoral fins
Vertebrae The bones of spinal column
Vestigial Reduced or very poorly developed
Villiform teeth Small, slender teeth forming velvety bands
Viviparous Species that gives birth to live young
Vomer A bone forming the front part of the mouth roof
Vomerine teeth Teeth on the vomer
Fish Xanthism (xanthic, xanthochroism) An unusual colour variety in which the normal colouration of a fish is largely replaced by yellow pigments
Yolk sac A bag like ventral extension of the primitive gut containing the yolk
Yolk sac larva Developmental stage beginning with hatching and ending with exhaustion of yolk reserves and characterized by presence of a yolk sac