Bloch, 1795

Organism information awaits expert curation

Genus: Zebrasoma
Species: velifer
Common Name (s): Sailfin tang, Pacific Sailfin Tang, Desjardin's Sailfin Tang, Eastern Sailfin Tang, Pacific Sail-fin Surgeonfish, Purple-lined Tang, Ringed Tang, Sailfin Surgeonfish
Dorsal spines (total): 4 - 5; Dorsal soft rays (total): 29-33; Anal spines: 3; Anal soft rays: 23 - 26. Smalls juveniles have alternating yellow and black bars. No brush-like patch of setae posteriorly on side of body. Dorsal fin very elevated, the longest ray 2.1 to 2.5 times in SL.


Classification Biota

  • Animalia (Kingdom)
  • Chordata (Phylum)
  • Vertebrata (Subphylum)
  • Gnathostomata (Superclass)
  • Actinopterygii (Class)
  • Perciformes (Order)
  • Acanthuridae (Family)
  • Acanthurinae (Subfamily)
  • Zebrasoma (Genus)
  • velifer (Species)

Vernacular Name (s)

Name Language Used In Country
ചുരിയന് Malayalam India
Churiyan Malayalam India
Gali-voulang Maldivian India

Synonym (s)

  • Acanthurus velifer (Bloch, 1795)
  • Zebrasoma veliferum (Bloch, 1795)(misspelling)


Bloch, M. E. (1795). Naturgeschichte der ausländischen Fische. Berlin. v. 9: i-ii + 1-192, Pls. 397-429. [Also a French edition, Icthyologie, ou Histoire naturelle des Poissons, v. 12, published 1797.]

Basis of record (s)

  • Rao, D.V., K. Devi and P.T. Rajan (2000). An account of ichthyofauna of Andaman and Nicobar Islands, Bay of Bengal Occasional paper no 178 Records of the Zoological Survey of India ZSI, Calcutta 1-434.
  • Murty, V.S. (2001). Ornamental fish resources of Lakshadweep Bulletins of the Geological Survey of India, 56: 103-111.
  • Anand, P.E.V and N.G.K. Pillai (2003). Habitat distribution and species diversity of coral reef fishes in the reefslope of the Kavaratti atoll, Lakshadweep, India Journal of the Marine Biological Association of India The Marine Biological Association of India, Cochin 45(1): 88-98.
  • Murugan, A., and N. Namboothri (2012). Finfishes of the Gulf of Mannar. A field identification guide. Dakshin foundation, Bengalure.

Additional source (s)


Name bearing type (s)

Acanthurus velifer Bloch [M. E.] 1795:106, Pl. 427 (fig. 1) [Naturgeschichte der ausländischen Fische v. 9] No locality [India, Indian Ocean]. 
Holotype (unique): ZMB 1753. 
Type catalog: Paepke 1999:41 

Name bearing specimen Availability

Species: Zebrasoma velifer (Bloch, 1795)
Verbatim Locality: Raja Ampat, Irian Jaya Barat, Indonesia
Basis of Record: Human Observation
Dataset: iNaturalist Research-grade Observations
Catalogue Number: 2653747
Decimal Latitude: -2.028633
Decimal Longitude: 130.734617

Related species

Zebrasoma desjardinii (Bennett, 1836)
Zebrasoma scopas (Cuvier,1829)


X-ray/ Microscopic/SEM Image/ (s)

SEM image of otolith of Z. velifer.

Line diagram/ Images

The general appearance of Z. velifer with its striking vertical bands and wing-like dorsal and anal fins.


Sexual dimorphism/ Reproduction

The sexes are separate among the acanthurids. There is a possibility of sexual dimorphism in Zebrasomas with cloacas bigger in females. This dimorphic character most probably applies to all Zebrasomas. It was observed to form spawning aggregations on the Great Barrier Reef (Squire and Samoilys unpub.), it spawns in pairs.

Parental care

Nonguarders; open water/substratum egg scatterers

Fecundity/ Larval development

As with other species in the family Acanthuridae, this species has a specialized pelagic, dispersing larval stage before the juvenile stage. This is referred to as the acronurus larval stage. This particular larval stage is responsible for the broad geographical distribution found within this species.

This species has small (less than 1 mm) pelagic eggs with a single oil droplet. When the poorly-developed larvae hatch (after about 1 day), they soon develop serrate ridges on the head. The pelvic and second dorsal spines form next followed by the second anal spine. Next, the head and trunk become deepened. The body becomes kite-shaped, accentuated by the long pelvic, dorsal, and anal spines. Small, triangular scales form in vertical rows. Late in the larval stage, the juvenile coloration becomes evident and the caudal peduncle spine develops.

Communication & Perception/ Behaviours

Members of this species communicate with each other and with other species of fishes in a number of ways. Like most other ray-finned fishes, this species uses visual displays as a means of communication. Color changes are observed in males during arousal, either during intraspecific competition or spawning. Also during intraspecific competition, the caudal peduncle spine may be brightly colored and positioned at an angle toward the competitor. Like many other species of fish, Z. veliferum also uses pheromones to communicate. These chemical signals can be detected by conspecifics or by closely related species.

Communication Channels: visual ; tactile ; chemical

Other Communication Modes: pheromones

Perception Channels: visual ; tactile ; chemical

Max. length/Age at maturity/ length and weight data

Max length: 40.0 cm SL male/unsexed
Bayesian length-weight: a=0.02399 (0.01473 - 0.03906), b=2.94 (2.80 - 3.08), in cm Total Length, based on LWR estimates for this species & (Sub)family-body

Life Span

Maximum age was 30 years in the Great Barrier Reef, Australia.

Threat To Human


Disease/ symbiotic relationship

These fish live among coral reefs, constantly interacting with each other and with individuals of other species. They are prey for cartilaginous fishes and other bony fishes. They consume benthic algae and occasionally zooplankton. Zebrasoma desjardinii is known to be associated with symbiotic microorganisms that reside in its digestive tract. These microorganisms, named Epulopiscium fishelsoni, were thought to be eukaryotic protists at first, but later they were determined to be unusually large bacteria. The size of the bacteria appears to be correlated to the host feeding ecology.

Mycobacterioses, or tuberculosis, are bacterial diseases that affect both freshwater and marine species of fishes. Mycobacterioses are caused by highly resistant bacteria which are difficult to control. These bacteria can be found in both wild and captive Z. veliferum. The most commonly isolated species of these bacteria in Acanthuridae are Mycobacterium fortuitum, M. marinum, and M. chelonae.

Mutualist Species:

Epulopiscium fishelsoni

Commensal/Parasitic Species:

Mycobacterium fortuitum
Mycobacterium marinum
Mycobacterium chelonae

Phylogeny Diversity Index

Phylogenetic diversity index: PD50 = 0.5078 [Uniqueness, from 0.5 = low to 2.0 = high].


Anti-predator Adaptations: aposematic


Feeds on leafy macroalgae. It possesses fewer and larger pharyngeal teeth, compared to the other Zebrasoma spp.


This species is prey for anything near the reef that is large enough to consume it. An example of such a predator is the whitetip reef shark, Carcharhinus albimarginatus. To avoid predation, Z. veliferum typically feeds during the day and hides among the reef at night. This species also has a sharp caudal spine that may act to deter predators. To advertise this protection, the tail fin is aposematic: the bright yellow coloration most likely serves as warning to predators.

Known Predators:

whitetip reef sharks (Carcharhinus albimarginatus)
cartilaginous fishes (Chondrichthyes)
larger bony fishes (Actinopterygii)


IUCN Status

Least Concern (LC) ver 3.1 accessed on 26 September 2017

Protection status under Indian Acts

This species is not protected under Indian Wildlife (Protection) Act, 1972.

Threats to species

Zebrasoma veliferum is a component of subsistence fisheries and is found in localities where coral reef degradation is prevalent.

Surgeonfishes show varying degrees of habitat preference and utilization of coral reef habitats, with some species spending the majority of their life stages on coral reef while others primarily utilize seagrass beds, mangroves, algal beds, and /or rocky reefs. The majority of surgeonfishes are exclusively found on coral reef habitat, and of these, approximately 80% are experiencing a greater than 30% loss of coral reef area and degradation of coral reef habitat quality across their distributions. However, more research is needed to understand the long-term effects of coral reef habitat loss and degradation on these species' populations. Widespread coral reef loss and declining habitat conditions are particularly worrying for species that recruit into areas with live coral cover, especially as studies have shown that protection of pristine habitats facilitate the persistence of adult populations in species that have spatially separated adult and juvenile habitats.

CITES / CMS status

This species is not assigned in Appendices I, II and III of CITES 2013.


Moderate vulnerability (37 of 100).


Ribosomal sequences

GenBank: AY057323.1; GenBank: AY057275.1


GenBank: AGK35232.1
GenBank: AGK34331.1


GenBank: KC831151.1
GenBank: KC623937.1
GenBank: KC623729.1


Depth range

Depth range 1 - 45 m, usually 2 - 30 m .

Geo Co-Ordinates

  • Tamil Nadu
  • Lakshadweep

Habitat Characteristics

Zebrasoma veliferum is usually encountered as solitary individuals, but occasionally in pairs, on coral reefs from shallow protected areas to outer reef habitats at least as deep as 40 m.


Western Indian Ocean: Mozambique . Pacific Ocean: Indonesia to the Hawaiian and Tuamoto islands, north to southern Japan, south to the southern Great Barrier Reef, New Caledonia, and Rapa Island. Replaced by the similar Zebrasoma desjardinii in the Indian Ocean.

In situ image/video (s)

Z. velifer in coral habitat.

Distribution Map

The distribution range of Z. velifer as per IUCN status.

Spectral Data


Environmental Parameters

Temperature range (°C): 25.275 - 29.336
Nitrate (umol/L): 0.047 - 0.862
Salinity (PPS): 34.131 - 40.307
Oxygen (ml/l): 4.314 - 4.728
Phosphate (umol/l): 0.100 - 0.301
Silicate (umol/l): 1.005 - 4.752

Population Biology

Zebrasoma veliferum is common in most parts of its range but not locally abundant. It was recorded as more abundant in offshore stations sampled at the Nha Trang Bay MPA and was found to be associated with branching corals. It is common in Milne Bay Province, Papua New Guinea and in Raja Ampat, Indonesia. It is occasional in Palawan Province, Philippines.

It is rare in the Guam fishery (<1% of the acanthurid fishery - Division of Aquatic and Wildlife Resources unpub. data). There was an average of 4,000 fish/year from 1992-2001 exported from a number of locations (most come from the Philippines). In 2007 in Hawaii, 57 lbs. were landed as bycatch, 93 lbs. in 2004. This species is not targeted.

In Moorea, French Polynesia, SPOT satellite images allowed estimation of the surface area of fringing reef (1,076 ha), barrier reef (3,788 ha) and outer slope (493 ha). A total of 84,118 individuals were recorded in this area in fish visual surveys conducted from 1990-1993. It is uncommon in the American Samoa National Park.

In the central Philippines, density and biomass of herbivorous fish in reserves had positive relationships with duration of reserve protection. Acanthuridae and Labridae (parrotfishes) were the major families that increased in biomass inside reserves with duration of reserve protection. For Z. veliferum, mean biomass of 0.19 kg per 500 m2 was recorded at one reserve (5 to 7 years of protection). It is common but not abundant in the Philippines. Frequency of occurrence is <10% in the Philippines based on Underwater Visual Census (C. Nanola pers comm. 2010).

Trophic level

Trophic Level:  2.0 ± 0.00 se; Based on food items.

Uses/ commercial value

Zebrasoma veliferum is harvested for food and is usually caught in traps in parts of its range and caught using spears in Guam. Because of its larger size, it is of greater value as food fish than Z. flavescens or Z. scopas. It is also a component of the aquarium trade.

Links for support literature



Medium, minimum population doubling time 1.4 - 4.4 years (K=0.282; Tmax=27).


  1. Anand, P.E.V and N.G.K. Pillai (2003). Habitat distribution and species diversity of coral reef fishes in the reefslope of the Kavaratti atoll, Lakshadweep, India Journal of the Marine Biological Association of India The Marine Biological Association of India, Cochin 45(1): 88-98.
  2. Bloch, M. E. (1795). Naturgeschichte der ausländischen Fische. Berlin. v. 9: i-ii + 1-192, Pls. 397-429. [Also a French edition, Icthyologie, ou Histoire naturelle des Poissons, v. 12, published 1797.]
  3. Murty, V.S. (2001). Ornamental fish resources of Lakshadweep Bulletins of the Geological Survey of India, 56: 103-111.
  4. Murugan, A., and N. Namboothri (2012). Finfishes of the Gulf of Mannar. A field identification guide. Dakshin foundation, Bengalure.
  5. Rao, D.V., K. Devi and P.T. Rajan (2000). An account of ichthyofauna of Andaman and Nicobar Islands, Bay of Bengal Occasional paper no 178 Records of the Zoological Survey of India ZSI, Calcutta 1-434.


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
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
Anal fin - the fin on the median line behind the vent 
Ankylosed - grown firmly together 
Anterior - relating to the front portion
Antrose - turned forward 
Anus - the external opening of the intestine, the vent 
Artisan fishing - a small scale commercial or subsistence fishing practices
Asperity - roughness of surface 
Attenuate - tapering to a point
Axillary - process an enlarged, pointed scale projecting from the insertion of the pectoral or pelvic fin
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 
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 
Carinate - keeled, having a ridge along the middle line 
Caruncle - a fleshy outgrowth 
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
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 
Dendritic - resembling a tree or shrub 
Dentate - with tooth-like projections 
Depressed - flattened from top to bottom 
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
Distal - remote from the point of attachment 
Dorsal fin - fin on dorsal side
Dorsum - the upper surface of the head or body 
Electrocyte - a cell that generates electricity 
Elongate - extended, drawn out 
Emarginate - with the margin slightly hollowed 
Endemic - restricted to a particular region
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 
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 
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 
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 
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
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 
Hyperostosis - a condition resulting in enlargement of areas of bone
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)
Larval teeth - are little exerted spines on the premaxilla or dentary 
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 
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 - a 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 
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 
Swimbladder - 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 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   
Yolk sac - a bag like ventral extension of the primitive gut containing the yolk