Dictionary of Ichthyology
Brian W. Coad and Don E. McAllister
V
V = 1) abbreviation for ventral (pelvic) fins.
V = 2) abbreviation for vulnerable in the IUCN Categories, q.v.
V = 3) abbreviation for utilised stock (the part, by number, of the fish alive at a given time, which will be caught in the future (Ricker, 1975)).
v = 1) abbreviation for vide, meaning see.
v = 2) abbreviation for visum, meaning seen.
v = 3) abbreviation of volume.
v = 4) abbreviation of varietas, meaning variety.
v = 5) abbreviation of vel, meaning or.
v = 6) versus, in contrast to. Also as vs.
v. et. = abbreviation for vide etiam, meaning see also.
v-cut = an acute, v-shaped cut containing the pin bones (q.v.). The cut is made through a skinned fillet along both sides of the line of the pin bones from the neck towards the tail such that both cuts meet just behind the position of the last pin bone.
vaam = said of a fisherman who catches no fish (Shetland Isles dialect). Also spelled vam, vamm and vaum.
vaarnakle = varnangle.
vaav (noun) = 1) a woollen thread used to tie a bait to an old-fashioned wooden hook or pin (Shetland Isles dialect). Also spelled vav. See also varnangle.
vaav (verb) = 2) to fasten a soft bait on a hook by tying a thread round both (Shetland Isles dialect). Also spelled vav.
vadal = floating close to shore.
vadose = of, relating to, or being water or solutions in the earth's crust above the permanent groundwater level.
vagal lobe = an enlargement in the dorsal medulla oblongata associated with connections of the vagus nerve and, in some species, the glossopharyngeal nerve.
vagile = freely motile; wandering; mobile.
vagility = the tendency of an organism or population to change its distribution with time; the ability to move from place to place.
vagrant = a species that has strayed beyond its natural range but not established reproducing populations.
vagus nerve = the Xth cranial nerve, sensory to pharynx, oesophagus, thoracic and abdominal viscera. innervates pharyngeal musculature, visceral musculature, trunk lateral line, visceral arches behind third, respiratory movement. See cranial nerves.
vain name = nomen vanum.
vaity-kabe = an upright piece of wood fitted on the gunwale of a boat with a tip notch to enable fishing line to run freely (Shetland Isles dialect). See also waith horn.
valiculture = seasonal confinement in natural lagoons as a means of fishery management.
valid = used of an available name or nomenclatural act that is acceptable according to the International Code of Zoological Nomenclature and in the case of name, one which is the correct name of a taxon in an author's taxonomic judgment.
valid name = the correct name for a taxon: a taxon may have several available names, but only one of those names (most frequently the oldest) is the valid name. The valid name is always an available name (q.v.) (the reverse is not always true). An invalid name may be either an available or unavailable name.
valid species = a species that has an existence in the real world and is recognised as such. In opposition to a species thought to be distinct but which does not actually exist, is no longer recognised, or is treated as a synonym.
validated name = a formerly invalid or unavailable name that has been made valid or available by the International Code of Zoological Nomenclature, e.g. by annulment or suppression of senior homonyms or synonyms.
validation = 1) to make valid or available a formerly invalid or unavailable name or invalid nomenclatural act.
validation = 2) confirming the accuracy of ageing methods that use skeletal structures like otolith zones by showing that the zones do refer to age.
valliculture = fish culture in brackish water bodies (valli) based on seasonal migrations in Italy. The valli have a fish weir that separates them from the sea; eels and mullets are common species.
valve, buccal = oral valve (the flap attached just inside the jaws which stop water escaping from the mouth during exhalation, helping to maintain a unidirectional flow. Usually a valve is found just inside the ring of teeth in the jaw).
valve, oral = oral valve; valve, buccal.
valvula (plural valvulae) = a small valve.
valvula (plural valvulae) = any structure preventing a backflow. See valve, buccal.
valvula Bauhini = a ring-shaped structure between the mid-gut and the hind-gut of some fishes; others have none.
valvula cerebelli = a continuation of the base of the cerebellum projecting anteriorly into the area of the posterior floor between the two optic ventricles. Fish with a large valvula cerebelli have a better developed lateral line system.
valvulae = plural of valvula.
vam = vaam.
vamm = vaam.
vam'd = voamd.
van gogh = a gene name for a zebrafish mutation affecting the ear (abnormal ear morphology). See also einstein, half stoned, what's up, rolling stones, among many others.
var. = abbreviation for variety.
variant = any individual or group that deviates from the typical behaviour or anatomy.
variant spelling = different spellings of specific or subspecific names that are deemed to be identical for the purposes of the Principle of Homonymy.
variation = divergence in structure or function not attributable to age, sex or life history stage.
variegated = an irregular pattern of small, dark and pale markings and many dark marks connected.
varietas = variety. Abbreviated as v.
variety = an ambiguous term of classical taxonomy for a heterogeneous group of phenomena including non-genetic variations of the phenotype, morphs, domestic breeds, and geographic races. Before 1961, according to the International Code of Zoological Nomenclature, use of the term "variety" is not to be interpreted as an express statement of either subspecific or infrasubspecific rank and after 1960, a new name published as that of a "variety" is to be regarded as of infrasubspecific rank.
varnangle = a wooden pin used as a hook, lodging cross-wise in the mouth of a fish (Shetland Isles dialect). Also spelled vaarnakle.
vas deferens = a paired structure of the testes carrying sperm when joined as a genital sinus to the exterior between the urinary papilla and the anus.
vasodentine = dentine with branching blood vessels but lacking dentinal tubules, e.g. teeth of Merluccius.
vasp speyr = waster (a fish spear or leister used especially on salmon (Scotland). Also called wester, wasper, waspeir, wausper, wawsper, vauch spear and wasp speir).
vate = a large, box-like trough in which cod livers were placed to render oil (Newfoundland). See also vate and fat.
vate = vat.
vauch = a bank or mound of stones set up in a river as a salmon trap (Scottish dialect).
vauch net = a salmon net used at a vauch, q.v.
vauch spear = waster (a fish spear or leister used especially on salmon (Scotland). Also called wester, wasper, waspeir, wausper, wawsper, wasp speir and vasp speyr).
vaum = vaam.
vav = vaav (1 and 2).
VAV = a ventro-lateral row of photophores running from the pelvic fin insertion to the anal fin origin.
VD link = backstrop link (a triangular steel link with rounded corners on the back of a trawl's otter board. The backstrop is attached here. Also called board link, door sling ring and shearboard link).
VD trawl = Vigneron-Dahl trawl (the usual rig of an otter trawl with long cables that frighten fish toward the net).
vector = an organism which carries or transmits a pathogen. Introductions of fishes to new water bodies may make a fish a vector.
vee = one of the two v-shaped corners of a cod trap next to the door or entrance (Newfoundland). See also back-end vee.
vegaquarian = vegequarian.
vegetal colouration = a general resemblance to vegetation shown by fish concealing themselves from predators or prey.
vegetal pole = opposite to the animal pole on the egg. Later in embryonic development corresponds to the point on the yolk cell furthest from the developing blastodisc.
vegetative fish cover = any live (e.g. algal mats, reed beds, lily pads) or dead (e.g. logs, branches) plant materials that provide cover for fish of varying ages.
vegequarian = a vegetarian who eats fish.
veil = a large mucous sheet, the egg membrane of Lophius, based on its shape.
vel = or. Abbreviated as v.
velar tentacles = short bristled barbels or tentacles which radiate inwards about the mouth from the velum in Amphioxi. Prevent undesirable objects from entering the digestive cavity. Also present in Petromyzontidae at the junction of the pharynx and oesophagus.
velocity = the speed of water flowing in a watercourse.
velocity barrier = a physical structure, such as a barrier dam or floating weir, built in the tailrace of a hydroelectric powerhouse, which blocks the tailrace from further fish migration to prevent physical injury or migration delay.
velterin = a half-grown cod (Shetland Isles dialect).
velum = 1) a membrane, veil, covering, curtain.
velum = 2) a vertical membrane surrounding the mouth from which the velar tentacles erupt in Amphioxi.
velum = 3) the membrane guarding the opening of the blind pharynx in Petromyzontiformes from which spring the velar tentacles.
velvet disease = gold dust disease (an infectious disease caused by dinoflagellates evidenced by a golden or brownish dusty appearance on the fish skin through mucus production. The fish may show irritability, flashing, respiration difficulties and clamping of the fins. A very contagious and often fatal disease in aquaria. Called velvet disease when Oodinium (or Piscinoodinium), coral fish disease when Amyloodinium and also rust from the appearance).
ven = fin of fish (Newfoundland).
venom = the poison secreted by the venom apparatus of an animal. Venoms are usually a large molecular protein or are in association with a protein which may serve as a carrier, but there may be many exceptions to this generalization.
venom apparatus = the traumagenic device (spine, tooth, etc.), venom gland, and accessory organs directly concerned with the introduction and transmission of a venom.
venomous fishes = those fishes that produce their poisons by means of glandular structures and are equipped with a spine or other traumagenic device to purvey their venoms. The poisons are parenteral toxins, usually large molecules, and are readily destroyed by heat or gastric juices. Also called ichthyacanthotoxic or acanthotoxic fishes.
venomous fishes, treatment of poisoning from = in all cases qualified medical attention should be sought immediately. The following
suggestions give some basic assistance and indicate severity of poisoning and are taken from Halstead (1970):-
1) sting rays including Dasyatidae, Gymnuridae, Mobulidae, Myliobatidae, Potamotrygonidae, Rhinopteridae, and Urolophidae -
irrigate wound with cold seawater, explore wound and remove all pieces of integumentory sheath, after thorough cleansing soak injured part in water as hot
as can be borne without damage for 30-90 minutes. Magnesium sulphate may be added to the water as a mild anaesthetic. Following soaking the wound may be debrided,
cleansed and closed with dermal sutures. Anti-tetanus agents are recommended, antibiotic agents may be required. Intramuscular or intravenous demerol has been
found effective in controlling pain. Primary shock can be treated with the usual measures. Secondary shock from action of venom on the cardiovascular system may
require immediate and vigorous therapy - maintaining cardiovascular tone and preventing complications. Elevation of the injured member is advisable. Do not
use potassium permanganate, ammonia or cryotherapy. Stingrays can be avoided by shuffling one's feet along the bottom.
2) catfish stings including Ariidae, Bagridae, Clariidae, Doradidae, Heteropneustidae, Ictaluridae, Pimelodidae, Plotosidae, Siluridae - treatment is similar to
that for stingray stings, see above.
3) weaverfish stings, Trachinidae - treatment is similar to that for stingray stings, see above. In addition calcium gluconate alleviates pain;
procaine injections may be used for less severe cases; and intravenous meperidine helps relieve severe pain which continues beyond the first hour after injury.
4) scorpionfish stings, Scorpaenidae - punctures should be thoroughly cleansed to remove venom. Bleeding should be encouraged. Soak
injured part in water as hot as can be borne without damage to the tissues for 30-90 minutes. Magnesium sulphate may be used in the water as a mild anaesthetic.
Surgical closure of the wound is not usually required. Anti-tetanus agents are recommended, antibiotic agents may be required. Intramuscular or intravenous
demerol may or may not help control pain. Secondary shock from the venom may require vigorous therapy to maintain cardiovascular tone and avoid complications.
5) stonefish (Synanceja) stings - this envenomation is very dangerous. Prompt immersion in hot water is recommended. Injection of emetine
hydrochloride into the wound has been found of value (0.5-1.0 ml of solution of 1 g of emetine hydrochloride per ml), apparently having an antagonistic action
against the venom and relieving the pain. Injections of 0.1 to 0.5 ml of 5% potassium permanganate and congo red have also been recommended. 2 ml of the
Australian anti-venom is recommended. Initially intramuscularly, but if the case is severe the intravenous route may be used. If symptoms persist another 2 ml
may be used. This anti-venom has been used with encouraging results with Scorpaena stings and is recommended for serious types of scorpionfish stings that do not
otherwise respond to treatment. Anti-venom is available from the Commonwealth Serum Laboratories, Melbourne, Australia
6) toadfish stings, Batrachoididae - treatment as for scorpionfish stings, see above.
7) rabbitfish, Siganidae, and surgeonfish, Acanthuridae, stings - treatment is similar to scorpionfish stings, see above.
venom pore = the opening of the poison gland behind the pectoral fin in certain Ictaluridae (Noturus).
vent = 1) the posterior opening of the intestine, gonads and kidney ducts in front of the anal fin.
vent = 2) geothermal vent (a vent of hot, mineral-rich water on the ocean floor, usually near spreading oceanic ridges or subduction zones, with an associated fauna including fishes).
venter = relating to the underside, the abdomen. See also ventrum.
venterohyal = ventral hypohyal, see hyoid arch.
ventrad = toward the underside; ventral to.
ventral = pertaining to the lower surface or abdomen, opposite to the back or dorsal side.
ventral adipose fin = a fin before the anal fin on the belly.
ventral aorta = artery from the heart (the bulbus arteriosus) to the aortic arches, q.v.
ventral disk = sucker formed by the pelvic fins.
ventral adipose fin = a fin before the anal fin on the belly.
ventral fin fold = the lower finfold.
ventral fin marsupium = the name applied to the brood-pouch in Solenostomidae. It is a pouch formed by the pelvic fins, provided with many long filaments, and found only in the female.
ventral fins = the paired fins other than the pectoral fins (placed right behind the gill slit); may be located behind, below or in front of the pectoral fins. Sometimes lacking. Also called pelvic fins.
ventral photophores = a row of light organs along the abdomen on either side of the midventral line between the ventral and anal fins in Myctophidae. Abbreviated VO.
ventral rib = one of the ribs surrounding and protecting the viscera and articulating with the parapophyses of the vertebrae. Also called pleural or pleuroperitoneal ribs.
ventral stripe = a series of melanophores just ventral to the myotomes.
ventrčche = the region of the abdomen of tunas where the muscles are divided into lamella separated by fatty inclusions (France). Only applied to Thunnidae.
ventresca = belly strips of albacore cooked in brine and packed with olive oil in barrels or cans (Italy), cf. tarantello from bluefin tuna.
ventricle = 1) a heart chamber collecting blood from the atrium and delivering it to the conus arteriosus and mediating the second, major component of the heart beat. The ventricle is a thick and muscular chamber with a small opening into the bulbus arteriosus.
ventricle = 2) a fluid-filled brain cavity, one of a series of expanded parts of the central canal, q.v The two lobes of the telencephalon contain the two anteriormost ventricles, the diencephalon contains the third ventricle, an optic ventricle forms the interior of each of the mesencephalic lobes, and dorsal half of the myelenocephalon contains the fourth ventricle.
ventriculo-bulbar valve = one of the valves at the junction of the ventricle and bulbus arteriosus in the heart, q.v.
ventrohyal = ventral hypohyal (the hypohyal is the one or two deep, endochondral bones in the hyoid arch between the ceratohyal and the glossohyal. Articulates dorsally with the ceratohyal and ventrally with the basihyal. Lepisosteus has only one while Gadus has two, the dorsal hypohyal or dorsohyal and the ventral hypohyal or ventrohyal).
ventrolateral = the region between the ventral and lateral surfaces; the lower side of the body.
ventronasal photophore = the light organ in front of the eye below the nostrils in Myctophidae. Abbreviated VN.
ventrum = the underside of the body, the belly. See also venter.
venture = adventure (a commercial fishing enterprise).
venturi filter = a protein skimmer, q.v., with a cylindrical body used to draw air through a rapid current of water.
venulose = full of venules or small veins; having a structure patterned like a group of small veins, e.g. used to describe an area of the flank behind the gill opening in Thryssa mystax (Engraulidae).
verandah net = a net designed to trap leaping fish with a vertical component as a barrier and a verandah or floating component (sometimes a trammel net) to catch the fish as they try to leap over the barrier. The barrier can be set in a straight line or in an open circle shape, or may be set from two boats to encircle a school.
vere = the true.
vermicide = any chemical used to kill or expel intestinal worms. See also vermifuge.
vermiculation = a worm-like marking, e.g. one of a series of wavy markings on the back of such fishes as the brook trout, Salvelinus fontinalis.
vermiform = worm-shaped.
vermifuge = an agent that kills or expels intestinal worms. See also vermicide.
vermivore = a feeder on worms and worm-like animals.
vernacular name = the name of a taxon in any language other than the language of zoological nomenclature; vernacular names have no status in zoological nomenclature, except certain family-group names (which were later latinized and generally accepted by zoologists interested in the group). Also called popular name, common name. Some efforts have been made in ichthyology in North America to stabilise a single name for each species as scientific names are dynamic and can change as understanding or relationships change.
vernal = pertaining to spring.
vernal pond = a pond occurring for a short period in the spring.
vernal-autumnal pond = a pond containing water in the spring, drying up in the summer, and filling up with water in the autumn.
verrucate = having wart-like prominences.
verrucose = covered with small dermal warts or having a rough surface.
verrucous = verrucose.
versatile = capable of being turned either way.
verso = any even numbered page of a book, on the left. Opposite of recto.
vertebra (plural vertebrae) = bony or cartilaginous elements surrounding the notochord or replacing it and often protecting the spinal cord and caudal vein. Vertebrae are composed of a centrum formed from two pleurocentra and two intercentra or parts of these elements, a neural arch formed by the interdorsal and basidorsal of each side, a neural spine fused to the neural arch, a haemal arch formed from the fusion of the interventral and basiventral, and a haemal spine fused to the haemal arch. Petromyzontidae lack centra and have a persistent notochord. Elasmobranchii have a centrum with a notochord core surrounded by a ring of cartilage (chordacentrum) to which the neural and haemal arches (arcocentra) attach and an outer ring of cartilage (autocentrum) interrupted by the arches. The cartilage becomes calcified (cyclospondylous, q.v., asterospondylous, q.v., tectospondylous, q.v.).
vertebra amphiclica (plural vertebrę amphiclicę) = amphicoelous vertebra (biconcave vertebrae, having both ends hollowed out, the condition in Elasmobranchii, Amia and most Teleostomi except Lepisosteus (also spelled amphicelous)).
vertebrę amphiclicę = plural of vertebra amphiclica.
vertebra aspondyla (plural vertebrę aspondylę) = aspondylous vertebra (a vertebra lacking a centrum although neural and haemal arches are well-developed, e.g. in Cyclostomata, Holocephali, Dipnoi, Acipenseridae).
vertebrę aspondylę = plural of vertebra aspondyla.
vertebra asterospondyla (plural vertebrę asterospondylę) = asterospondylous vertebra (a type of vertebra with radiating, star-like calcifications extending to the chordacentrum and autocentrum, e.g. in some Elasmobranchii).
vertebrę asterospondylę = plural of vertebra asterospondyla.
vertebra cyclospondyla (plural vertebrę cyclospondylę) cyclospondylous vertebra (vertebra consisting of calcified rings around the notochord in Elasmobranchii and Holocephali. The calcification extends only to the chordacentrum or notochordal sheath, the arches are cartilaginous).
vertebrę cyclospondylę = plural of vertebra cyclospondyla.
vertebra diplospondyla (plural vertebrę diplospondylę) = diplospondylous vertebra (the double vertebrae formed when the anterior and posterior elements (sclerotomes) have not fused, e.g. caudal vertebrae of Amia. Two types of centra are present, a precentrum lacking neural and haemal arches and a postcentrum having these arches).
vertebrę diplospondylę = plural of vertebra diplospondyla.
vertebra dissospondyla (plural vertebrę dyssospondylę) = dyssospondylous vertebra (vertebra in Amia, Lepisosteidae and Acipenseridae where the pleurocentrum, intercentrum, basidorsal, basiventral, interdorsal and interventral all ossify but remain independent in the embryonic and juvenile stages. Some elements fuse later and form vertebrae with two centra in the caudal region and typical vertebrae anteriorly).
vertebrę dyssospondylę = plural of vertebra dissospondyla.
vertebra holospondyla (plural vertebrę holospondylę) = holospondylous vertebra (a vertebra with a single-disk centrum, formed of a single bone with all elements (arches, spines) fused, e.g. Dipterus, Scaumenacia (Dipnoi), Teleostei).
vertebrę holospondylę = plural of vertebra holospondyla.
vertebra opisthoclica (plural vertebrę opisthoclicę) = opisthocoelous vertebra (vertebral centra which are concave posteriorly and convex anteriorly. e.g. in Lepisosteidae).
vertebrę opisthoclicę = plural of vertebra opisthoclica.
vertebra polyspondyla (plural vertebrę polyspondylę) = polyspondylous vertebra (vertebra showing polyspondyly, the notochord surrounded by many serially arranged calcified rays, in effect having several centra e.g. Chimaera has 5-9 centra, Amia has 2 in the caudal region).
vertebrę polyspondylę = plural of vertebra polyspondyla.
vertebra pręuralis (plural vertebrę pręurales) = preural vertebra (one of a series of vertebrae preceding the ural vertebrae and distinguished by lacking hypurals. They precede the bifurcation of the caudal artery. Called PU1, PU2, etc counted anteriorly from the first ural vertebra).
vertebrę pręurales = plural of vertebra pręuralis.
vertebra tectospondyla (plural vertebrę tectospondylę) = tectospondylous vertebra (vertebral centra (and arches) with several concentric ossifications instead of just one, extending to the chordacentrum, arcocentrum and autocentrum. Found in skates and rays).
vertebrę tectospondylę = plural of vertebra tectospondyla.
vertebra uralis (plural vertebrę urales) = ural vertebra (one of the vertebrae to which hypural bones are attached).
vertebrę urales = plural of vertebra uralis.
vertebrae = plural of vertebra.
vertebral column = the vertebrae from the skull to the caudal fin, protecting the spinal cord and haemal artery and forming an attachment for muscles used in swimming.
vertebral counts = usually all the vertebrae are counted. If sutures are present in the urostyle, the indicated elements are counted. When sutures are absent the urostyle (if present) is usually counted as one vertebra. Vertebral counts may be separated into abdominal (precaudal or prehaemal) and caudal (haemal) vertebrae. The first caudal vertebra has a definite haemal spine and is the first vertebra to enclose the caudal vein (although there may be complete haemal arches not enclosing the caudal vein). In some older works the vertebral count is given as a fraction, the abdominal vertebrae forming the numerator, the caudal the denominator. In Ostariophysi (Cypriniformes and Siluriformes) the vertebrae in the Weberian apparatus are included. Some authors also count prethoracic vertebrae separately.
vertex = top of the head; highest point of the skull.
vertical blood vessel = last vertical blood vessel (the most posterior blood vessel extending from the dorsal aorta to the nephros and used as a reference point in anguilliform larval descriptions).
vertical classification = grouping of ancestral and descendant stages of a phyletic line into a single taxon. Compare horizontal classification, q.v.
vertical distribution = upward and downward dispersion, location or arrangement as of fish in a water column.
vertical fins = the dorsal, caudal and anal fins (as opposed to the paired fins). Also called median fins.
vertical incubator = a larval incubator unit which allows water to flow upward so that high densities of eggs and larvae with any nutrients can be raised in a small space. There is usually some form of filtration at the base to absorb incoming suspended particles.
vertical integration = an aquaculture facility or a fishery that has wide control over all aspects of the process that grows or catches fishes and delivers them to consumers.
vertical jigging = in angling, lowering a lure to the bottom and then lifting it and allowing it to fall again, varying the depth until fish are located.
vertical migration = the upward and downward movement of fish in a lake or the ocean. Movement is usually into surface waters at night to feed and into deeper waters to avoid predators during the day.
vertical mixing = circulation of water from the surface to the depths in a lake and vice versa occurring naturally in temperate lakes in spring and autumn.
vertical scale disease = dropsy (a swelling of the fish's body usually caused by bacterial infection, and also by viral infection, osmoregulatory problems, a flagellate protozoan (Hexamita), aggravated by poor environmental conditions. Serous fluid accumulates in any body cavity. Other symptoms are lethargy, gasping, increased respiration, colour loss, skin ulceration and exophthalmia. Also called pinecone disease (and vertical scale disease) because the scales stick out, and ascites).
vertical slot fish passage = this fishway is similar to a pool-and-weir ladder except that each dam has a narrow slot in it near the channel wall. The channel allows fish to swim upstream without having to leap over the dam wall. This type of passage handles seasonal fluctuation in water levels quite well. See also DeNiel fishway, pool-and-weir ladder and rock-ramp fishway.
vertical transmission = disease spread from parent to offspring via gametes or embryos, cf. horizontal transmission.
very high output light = an aquarium fluorescent light giving a higher intensity light than normal bulbs. Used for reef systems which require strong light.
vesica piscis = 1) fish bladder (a figure composed of two equal and symmetrically placed circular arcs).
vesica piscis = 2) literally "vessel of the fish", the Christian symbol, a stylised fish. Of pre-Christian origin since it is formed from the intersection of two circles as noted above, a pythagorean symbol of the intersection of the world of the divine with the world of matter. The length-height ratio of the vesica piscis, as expressed by Pythagoras is 153:265, a mystical number known as "the measure of the fish". In the Gospel of John, where Jesus helps his disciples to catch fish, Jesus catches exactly 153 fish. This biblical story is thought to be a coded reference to the vesica piscis. Also associated with the goddess Venus.
vesica piscis = 3) an ovoidal frame much used in the 12th century, especially in painted windows, to surround pictures of the Virgin Mary and Jesus Christ. It is meant to represent a fish, from the anagram ICHTHUS.
vesicula seminalis = seminal vesicles (the enlarged lower end of the genital duct which is secretory in nature and completes the formation of the spermatophores and stores them. The so-called "seminal vesicles" of teleosts (Blennioidea, Gobioidea) are misnamed and do not store sperm. Siluriformes have seminal vesicles).
vesiculate = thin and bladder-like.
vespertine = of or relating to the evening; active or spawning in the evening.
vessel = a boat, ship or other craft that is equipped and used for fishing or in support of such activity with a capacity of 5 net tons or more. Also used for any object with room for one or more persons and as such would include everything from a canoe to a ship.
vessel catch limit = a limit on the quantity each individual vessel can land per trip or short period of time such as a day or week.
vessel class = commercial fishing vessels are classified according to their gross registered tons of displacement, e.g. vessel class 2 is 5-50 tons, 3 is 51-150 tons, 4 is 151-500 tons.
vessel fishery cure = the process of salting fish (usually cod) on board ship.
vessel monitoring system = a system for tracking fishing vessels electronically using satellites. Abbreviated as VMS. Also called a black box.
vestibule = a chamber leading into other cavities or passages, e.g. of the inner ear, of the utriculus, sacculus, lagena. Space within the oral hood of Amphioxi.
vestige (noun) = rudimentary or degenerate structures that have degenerated during evolution or ontogeny. A remnant of a structure that functioned earlier in development or evolution of the species.
vestigial (adjective) = rudimentary, degenerate; said of structures that have degenerated during evolution or ontogeny.
vexillifer larva = an elongate, planktonic, pre-adult stage of most, perhaps all, Carapidae characterized by a long, filamentous, usually ornamented dorsal appendage, the vexillum.
vexillum = a long dorsal appendage in larvae (vexillifer larvae) of Carapidae and Pyramodontidae. Commences as a small pigmented thickening on the front end of the dorsal fin, changes to a small papilla, then to a soft forked projection and finally a long-lobed complex structure. The appendage degenerates when the larva assumes a benthic mode of life. It is composed of bilaterally paired, segmented components, each of which contains a proximal and a distal element.
VHS = abbreviation for viral haemorrhagic septicaemia.
viable population = a population of fish in a state that maintains its vigor and its potential for evolutionary change.
vial = a small, round and straight-sided glass or plastic container used for storing smaller museum specimens or parts thereof; submerged in a larger glass jar filled with preservative in the case of fish so the contents do not dry up.
Vibert box = a box in which fish eggs are placed prior to burial in gravel for the purposes of hatching. Hatching success is apparently less for eggs in the boxes than those buried directly in the gravel.
vibriosis = an acute systemic bacterial disease caused by Vibrio anguillarum or other Vibrio spp., often in spring in juvenile anadromous salmonids after transfer to sea water in an aquaculture facility. Symptoms include ulcers, haemorrhaging, rapid breathing, dropsy, skin lesions, popeye and lethargy. Antibiotics are needed for treatment.
vibsanine = vibsanine A is a plant piscicide from the leaves of Viburnum awabuki (Caprifoliaceae), used in Okinawa, Japan. Other piscicidal plant chemicals include callicarpone, huratoxin, ichthyothereol, inophyllolide, juglone, justicidin, maingayic acid, and rotenone, all q.v.
vicar = 1) one of a pair or more of forms that are closely related and ecologically equivalent but separated by a geographical barrier. See vicarious species.
vicar = 2) the priest or cleric in charge of a parish. In the nineteenth century especially, often devoted to natural history.
vicariance = the presence of closely-related taxa or biota in different geographical areas; these have been separated by a natural barrier, a vicariant event, e.g. the rise of a mountain range isolating drainages.
vicariant = one of two or more closely related taxa isolated by a barrier.
vicarious fishes = those presumably non-diadromous freshwater representatives of partly or primarily marine groups, e.g. Siniperca, Lota, Plagioscion, freshwater Ariidae, Plotosidae, Apogonidae, Atherinidae and Syngnathidae; landlocked or non-diadromous Galaxiidae.
vicarious species = vicar.
vice = in place of.
vice-admiral = historically, the master of the second English fishing vessel to reach a harbour in Newfoundland, having certain privileges for the season under the fishing admiral (q.v.).
vide = see.
vide etiam = see also. Abbreviated as v. et.
videlicet = namely. Abbreviated as viz.
view = the appearance or aspect of a bone or other anatomical feature when viewed from a specific position.
Vigneron-Dahl trawl = the usual rig of an otter trawl with long cables that frighten fish toward the net.
village pond = a small pond, either natural or artificial and usually within a village, and occasionally used for fish culture.
villi = plural of villus.
villiform = crowded into coarse velvety bands or patches.
villiform teeth = fine, long, crowded teeth in a patch or band having the appearance of velvet.
villosa = short hair-like or finger-like processes.
villus (plural villi) = a slender hair-like process, as those which extend into the intestine. They normally function as sensory organelles or to increase surface area for absorption.
vinegar cured fish = fish preserved in vinegar, salt and sometimes spices.
vinegar eel = Turbatrix aceti, small (2mm), nematodes which live in weakly acidic water and are used as fish food. They are cultured in a special cider vinegar solution and fed pieces of rotting apple. The nematodes need to be filtered out of the solution using a funnel and a coffee filter.
vippick = a small fishing rod (Shetland Isles dialect).
viral haemorrhagic septicaemia = an acute or chronic disease of salmonids, such as rainbow trout in farm ponds, causing loss of appetite and of schooling behaviour, darkened colour, bleeding, hyaline gills and exophthalmia. It is associated with temperature changes and with the late winter and spring seasons when temperatures are below 8°C. Abbreviated as VHS. Also called Egtved disease and trout pest.
virgin = a fish (e.g. a salmonid, shad), whether male or female, which has not spawned, and is maturing to spawn. Also called a maiden.
virgin biomass = a stock's theoretical carrying capacity. The average biomass of a stock that has yet not been fished (in an equilibrium sense). Biomass of an unexploited (or quasi unexploited) stock. Rarely measured. Most often inferred from stock modeling. Used as a reference value to assess the relative health of a stock, monitoring changes in the ratio between current and virgin biomass (B/B0). It is usually assumed that, in absence of better data, B = 0.30 B0 is a limit below which a stock should not be driven. Abbreviated as B0, Bo or Bv.
virgin stock = a stock of fish that is never caught by fishing. Growth and recruitment add biomass while death removes biomass. The biomass stays steady apart from natural fluctuations caused by good and bad years.
virgin water = water not previously used for fish culture.
Virginia cure = gutted alewives, cured in strong brine for a week or more and packed in barrels with dry salt (U.S.A.). Also called tight pack, hard cure and pickled alewives (Canada).
virtual population = utilised stock (the part, by number, of the fish alive at a given time, which will be caught in the future).
virtual population analysis = an algorithm for computing historical fishing mortality rates and stock sizes by age or length, based on data on catches, natural mortality, and certain assumptions about mortality for the last year and last age group. Essentially reconstructs the history of each cohort or year class over its life in a fishery, assuming that the observed catches are known without error. Abbreviated as VPA. Also called cohort analysis.
virgin stock = a stock in its natural condition before anyone has fished it.
virr = the corner of fish mouth (Shetland Isles dialect).
virtual tautonymy = the nearly identical spelling, or same origin or meaning, in nomenclature, of a generic or subgeneric name and the species or subspecies name in a binomen or trinomen originally included in the genus (not a term regulated by the International Code of Zoological Nomenclature).
viscera (plural) = the organs in the body cavity of a fish.
visceral arch = one of the series of skeletal bars on either side of the pharynx, which comprise the gill arches and the jaws.
visceral clefts = the jaw, hyoid and gill arches.
visceral pericardia = a single membrane around the heart.
visceral peritoneum = a single membrane around the viscera.
visceral skeleton = the skeleton derived from the visceral arches, the mandibular arch forming the mandibles, the hyoid arch and the branchial arch, collectively called the splanchnocranium or viscerocranium.
viscerocranium = see visceral skeleton.
viscid egg = adhesive egg (a fish egg that is deposited on sand, gravel, plants, etc. to which it sticks by means of the egg's sticky surface. In aquaculture situations this is inconvenient and the adhesiveness can be removed by milk or tannin).
viscosity = a stock throughout its area of distribution does not have complete and instantaneous mixing of individuals. A fishery on one area of a stock will impact the whole stock on a time scale and to a degree that is a function of the stock's viscosity.
viscous = slimy.
viscus (singular) = one of the large internal organs found in the abdomen; usually appearing in plural form as viscera.
Vishnu = Mahavishnu took the form of a fish to retrieve the vedas from the Asura Hayagreevan (head of a horse) and also to safeguard herbs and seeds at the end of one cycle of creation.
visible implant tag = a small, alphanumeric tag (1-2 mm) implanted into any clear tissue such as behind the eye.
visible implant elastomer tag = a fluorescent plastic tag, visible externally although implanted into clear tissues with a small needle. The tag is liquid but becomes a pliable solid after injection. Often used to identify groups of fish.
visibility = the depth at which the black and white parts of a disk can just be distinguished; a measure of water clarity.
visual survey = an estimate of stock abundance made by counting fish, e.g. by a SCUBA diver, a camera set-up, from a submarine or from an aeroplane for surface schooling fish.
visual transect = a survey by sight of a sample area in a long continuous strip.
visum = seen. Abbreviated as v.
vital rates = rates (such as natural mortality, fecundity, and growth rates) affecting the dynamics of a stock.
vitamin C = ascorbic acid. A deficiency in fish manifests in spinal and hyaline cartilage abnormalities and reduced wound healing, through affects on normal collagen production.
vitelline membrane = a membrane, product of the ooplasmic surface which adheres closely to the outer boundary of the ooplasm, but as fertilization separates from the surface as a distinct membrane.
vitelline vein = incorrect name for the common cardinal vein (the anterior cardinal vein returns blood from the head and the posterior cardinal vein from the trunk, joining together as the common cardinal vein).
vitelline vesicles = arteries and veins of the yolk region.
vitreous body = the viscous liquid filling the eye between the lens and retina.
vitrodentine = the enamel-like substance covering the surface of cosmoid scales.
vitta = a stripe or band of colour.
vittal = adjective for vitta.
vivarium = a place where living fish and other organisms are kept as food (a stew), as objects of interest or for scientific study.
vivary = vivarium.
viver = vivier (1 and 2).
vivier = 1) boats and trucks that carry live fish.
vivier = 2) a fish pond.
viviparity = the condition of giving birth to active, free-swimming young.
viviparous = adjective for viviparity.
viz. = abbreviation for videlicet, meaning namely.
VLO = a photophore above the ventral fin in Myctophidae.
VMS = abbreviation for vessel monitoring system, a system for tracking fishing vessels electronically using satellites.
Vn = a photophore in front of the eye below the olfactory capsule of Myctophidae.
VO = a row of photophores on the abdomen behind the ventral fin in Myctophidae. Also called maculae ventrales.
voamd = tainted as with fish or meat (Shetland Isles dialect). Also spelled vomd or vam'd.
vol. = abbreviation for volume.
voltine = referring to the number of broods or generations, usually in a year or a season, e.g. univoltine, multivoltione.
volume of a lake = the sum of the volume in each of the start bounded by bottom contours.
volumetric unit quota = a quota based on volume of organisms taken.
vomd = voamd.
vomer = prevomer (a frequently toothed median or paired dermal bone in the middle of the roof of the mouth covering the ethmoid ventrally and in front of the parasphenoid. Incorrectly called vomer).
vomerine teeth = teeth on the vomer or prevomer.
von Bayer trough = a 30 cm v-shaped trough for counting fish eggs.
von Bertalanffy growth curve = a model of individual fish growth as a function of time. Named after its proponent, Ludwig von Bertalanffy, this growth curve is an entry point to more complex models of the dynamics of fish populations. The growth equation is Lt = L∞[1-e-K(t-to)] where t = age, L∞ = asymptotic length (mean length of a very old fish), and K = the curvature parameter showing how fast a fish approaches its maximum value. A short-lived species will have a high value of K and approach L∞ rapidly while other species have a low K and take a long time to reach L∞. These parameters can be estimated from the Ford-Walford method where length at a given age is plotted against length one year earlier. The intercept on the 45 degree line is L∞ and the slope is e-K.
voracious = said of fish which live mostly on other fish.
-vorous (suffix) = feeding upon.
voucher = supporting evidence providing tangible proof of something. May be a specimen, photograph, written record of diagnostic characters, etc.
voucher specimen = a specimen archived in a permanent collection (usually in a museum, an institution with a mandate to preserve materials indefinitely). It serves as physical evidence of occurrence at time and place and of any identifications and descriptions based on it, always assuming that it is archived with adequate collection data. Type specimens are voucher material.
voyage = 1) an extended offshore trip that involves a return to the point of origin. A passage is a leg of a voyage.
voyage = 2) the catch of fish taken, or the proceeds of the catch.
voyage = 3) the period of the offshore trip.
VPA = virtual population analysis.
vs. = versus, in contrast to. Also as v.
vulnerability = catchability, but usually applied to separate parts of a stock, for example those of a particular size, or those living in a particular part of the range (Ricker, 1975).
vulnerable = 1) that part of a population likely to be captured by a particular gear.
vulnerable = 2) in the IUCN Criteria for threatened species, a taxon is Vulnerable when it is not Critically Endangered or Endangered but is facing a high risk of extinction in the wild in the medium-term future. Abbreviated VU.
© Brian W. Coad (www.briancoad.com)