The golden-lined spinefoot (''Siganus lineatus''), also known as the goldlined rabbitfish or lined rabbitfish, is a species of marine

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of sk ...

, a

rabbitfish Rabbitfishes or spinefoots, genus ''Siganus'', are perciform fishes in the family (biology), family Siganidae. It is the only Extant taxon, extant genus in its family and has 29 species. In some now obsolete classifications, the species having ...

belonging to the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Siganidae Siganidae, the rabbitfishes, are a small family of ray-finned fishes in the order Perciformes. The only extant genus is '' Siganus'', the rabbitfish and spinefoot. However, a number of genera are known from fossils. The extant species are marine ...

. It is found in the tropical Western Pacific and along the coasts of

northern Australia The unofficial geographic term Northern Australia includes those parts of Queensland and Western Australia north of latitude 26th parallel south, 26° and all of the Northern Territory. Those local government areas of Western Australia and Q ...

Taxonomy

The golden-lined spinefoot was first formally described in 1835 as ''Amphacanthus lineatus'' by the French

zoologist Zoology ( , ) is the scientific study of animals. Its studies include the structure, embryology, classification, habits, and distribution of all animals, both living and extinct, and how they interact with their ecosystems. Zoology is one ...

Achille Valenciennes Achille Valenciennes (9 August 1794 – 13 April 1865) was a French zoology, zoologist. Valenciennes was born in Paris, and studied under Georges Cuvier. His study of parasitic worms in humans made an important contribution to the study of parasi ...

with the type locality given as the Western Pacific. The populations of spinefoots similar to '' Siganus lineatus'' in the waters off the Maldives, southern India and Sr Lanka had been considered to be

conspecific Biological specificity is the tendency of a characteristic such as a behavior or a biochemical variation to occur in a particular species. Biochemist Linus Pauling stated that "Biological specificity is the set of characteristics of living organism ...

with ''S. lineatus'' but differences in the colour and pattern as well as genetic differences showed that this was a valid,

allopatric Allopatric speciation () – also referred to as geographic speciation, vicariant speciation, or its earlier name the dumbbell model – is a mode of speciation that occurs when biological populations become geographically isolated from ...

species, '' S. insomnis''. The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

''lineatus'' means "lined", a reference to the wavy bands along its body.

Description

The golden-lined spinefoot has a laterally compressed body, which has a depth that is just over half its

standard length Fish measurement is the measuring of individual fish and various parts of fish anatomy, their anatomies, for data used in many areas of ichthyology, including Taxonomy (biology), taxonomy and fishery biology. Overall length Standard length (SL) is ...

. The dorsal profile of the head is steep and there is a slight indentation above the eyes. The front nostril has a low rim which is larger to the rear. There is a forward pointing spine in front of the dorsal fin which is embedded in the nape. Like all rabbitfishes, the

dorsal fin A dorsal fin is a fin on the back of most marine and freshwater vertebrates. Dorsal fins have evolved independently several times through convergent evolution adapting to marine environments, so the fins are not all homologous. They are found ...

has 13 spines and 10

soft rays Fish anatomy is the study of the form or morphology of fish. It can be contrasted with fish physiology, which is the study of how the component parts of fish function together in the living fish. In practice, fish anatomy and fish physiology co ...

while the

anal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported o ...

has 7 spines and 9 soft rays. The

caudal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported only ...

is emarginate to weakly forked. This species attains a maximum total length of , although is more typical. The overall colour is pale grey to bluish-grey, shading to silvery on the abdomen, marked with wavy orange lines. There is a large bright yellow spot underneath the soft rayed part of the dorsal fin, and blue lines on the cheek and operculum. The spines in the dorsal fin are golden with dusky bronze membranes while the rays are silvery with bluish membranes between them and there is a golden spot at the base of each ray. The spines of the anal fin are golden bronze with dusky blue membranes and the anal fin rays are bluish with their membranes being dusky, again with a golden spot at the base of each one and a bar at the bottom of it in each cell of the membrane. The caudal fin is bluish with rows of golden spots which look like 3 or 4 cross bars when the fin is furled. The outer spines of the

pelvic fin Pelvic fins or ventral fins are paired fins located on the ventral (belly) surface of fish, and are the lower of the only two sets of paired fins (the other being the laterally positioned pectoral fins). The pelvic fins are homologous to the hi ...

, and the outermost fin ray, are silvery, the rest are dusky blue. The

pectoral fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish aquatic locomotion, swim. Apart from the tail or caudal fin, fish fins have no direct connection with the vertebral column ...

s are

hyaline A hyaline substance is one with a glassy appearance. The word is derived from , and . Histopathology Hyaline cartilage is named after its glassy appearance on fresh gross pathology. On light microscopy of H&E stained slides, the extracellula ...

Distribution and habitat

The golden-lined spinefoot is found in the Indo-West Pacific from the

Gulf of Thailand The Gulf of Thailand (), historically known as the Gulf of Siam (), is a shallow inlet adjacent to the southwestern South China Sea, bounded between the southwestern shores of the Indochinese Peninsula and the northern half of the Malay Peninsula. ...

and the Philippines east to Vanuatu and south to northern Australia. In Australia it has been recorded from Point Quobba in

Western Australia Western Australia (WA) is the westernmost state of Australia. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to the south, the Northern Territory to the north-east, and South Australia to the south-east. Western Aust ...

east along the northern tropical coast to the Capricorn Group in southern

Queensland Queensland ( , commonly abbreviated as Qld) is a States and territories of Australia, state in northeastern Australia, and is the second-largest and third-most populous state in Australia. It is bordered by the Northern Territory, South Austr ...

, as well as at Ashmore Reef in the

Timor Sea The Timor Sea (, , or ) is a relatively shallow sea in the Indian Ocean bounded to the north by the island of Timor with Timor-Leste to the north, Indonesia to the northwest, Arafura Sea to the east, and to the south by Australia. The Sunda Tr ...

and Murray Island in the

Coral Sea The Coral Sea () is a marginal sea of the Pacific Ocean, South Pacific off the northeast coast of Australia, and classified as an Interim Biogeographic Regionalisation for Australia, interim Australian bioregion. The Coral Sea extends down t ...

. It has also been reported from the Ogasawara, Europic and

Caroline Islands The Caroline Islands (or the Carolines) are a widely scattered archipelago of tiny islands in the western Pacific Ocean, to the north of New Guinea. Politically, they are divided between the Federated States of Micronesia (FSM) in the cen ...

. It has been found as deep as in sheltered waters like lagoons and bays where they can be found near rocky substrates or reefs, often resting on rubble or sandy bottoms. Juveniles prefer estuaries.

Biology

Golden-lined spinefoots form schools which decrease in size with the age of the fish and range from 10 to 25 fish in the adults, although they may from aggregations of several thousand fish when

spawning Spawn is the Egg cell, eggs and Spermatozoa, sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of freely releasing eggs and sperm into a body of water (fresh or marine); the physical act is ...

. They feed on encrusting algae which they scrape off from beach rock or pavement areas of coral reefs, and on larger leafy algae. This species produces

venom Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a sti ...

in the spines of its fins. In a study of the venom of a congener it was found that rabbitfish venom was similar to the venom of stonefishes.

Fisheries

The golden-lined spinefoot is largely caught with set nets and fixed traps, and is commonly sold in fish markets as fresh fish.

References

External links

WoRMS

Animaldiversity WebFood and Feeding habitsScience direct
* {{Taxonbar, from=Q2372240 Siganidae Fish described in 1835 Taxa named by Achille Valenciennes