Trigloporus Lastoviza

– Streaked Gurnard –

The streaked gurnard (Trigloporus lastoviza) is a species of searobin found in the eastern Atlantic Ocean to the western Indian Ocean from Norway to Mozambique. It is found at depths of from 10 to 150 metres (33 to 492 ft) though it usually occurs at less than 40 metres (130 ft). This species grows to a length of 40 centimetres (16 in) TL and is a component of local commercial fisheries. This species is the only known member of its genus.^[1]

The Gallinella or Capon ^[1] ( Trigloporus lastoviza synonymous with Chelidonichthys lastoviza ), also known as the drunken capone or drunken capon , is a sea fish belonging to the Triglidae family . It is the only member of the genus Trigloporus .

Description

Gurnards have a characteristic silhouette, with a massive head , flattened under the mouth and protected by ridged and granular bony plates. The general shape of the body is slender, gradually tapering off as it approaches the tail, with a steep, almost vertical profile , very slightly curved, and very prominent eye sockets. The very marked and thorny lateral line * turns towards the caudal. The short , rounded muzzle , without thorns, ends in a flattened and very reduced rostrum * in two denticulate lobes. The mouth is wide, at the bottom of the head.

The striped gurnard is one of the most common gurnards on our coasts. It has two dorsal fins bordered by a groove of thorns. The first dorsal is thorny (9 to 11 rays). The second is formed by about fifteen soft rays. The pectorals are ample and folded back, they exceed the first ray of the anal. They have three lower rays free , independent and finger-like. They are reddish, striped with brown. They are endowed with sensory, olfactory and taste organs. They are also used to “walk” on the bottom.

The body of the striated gurnard has several thick spines, on the operculum *, on the shoulder and above the eye. Unlike other gurnards, it does not have a transverse groove on the nape. Its scales are small, inconspicuous and completely cover the body. It is the smallest of the gurnards. Its size can reach 40 cm but the average is between 10 and 25 cm. The flanks, with the exception of the belly, are marked with transverse and oblique dermal folds . Very colorful, its general livery is reddish on the back, sometimes carmine pink, sometimes brown, and clear on the belly, completed with spots or irregular bands distributed randomly over the whole body.The pectoral, reddish, deployed in a rounded fan, are bordered by a bright blue line and dotted with small aligned blue spots . Their inner face is stained with dark. Their rays are white. We can say that they look like wings.

Biotope

Benthic fish *, the striated gurnard is frequently found between 20 and more than 100 m of depth, although it can however be seen in small schools at the surface and up to 150 m. Generally, this fish is gregarious, installed on the continental shelf between 80 and 100 m. In summer, it will get closer to the coast and to the surface. The young are first pelagic * then coastal.
It lives near rocky bottoms, on sandy, detrital * or muddy soils, with a preference for muddy sediments. It can sometimes be found above Posidonia. It can be found on pockets of sand, near rock and seagrass.

Similar Species

Gurnards are represented by several similar species:
Lepidotriga cavillone , Cavillone: ​​very marked groove on the back of the neck; large marked scales; two thorns in front of the eye; angular lobes of the rostrum; (no tooth in the palate).
Lepidotriga dieuzeidei , Grondin de Dieuzeide: furrow little marked on the back of the neck; large, slightly ctenoid scales; no thorns on the eye; spiny lobes, rounded from the rostrum; (teeth in the palate).

Aspitrigla cuculus , Pine Gurnard or Red Gurnard : without groove on the nape; conspicuous “V” scales; without dermal folds; short pecs without blue border.

Chelidonichthys obscurus , Gurnard morrude: without groove or dermal fold; scales not prickly with a notched free edge.
Eutrigla gurnardus or Eutrigla lucerna , Gray gurnard : without groove or dermal fold; thorny scales; short pectorals; black spot on the dorsal; pearly white belly.

Trigla lyra , Grondin-lyre: without groove or dermal fold; short, straight and smooth scales; very indented muzzle.

Chelidonichthys lucernus , Gurnard -perlon: without groove or dermal fold; short, straight and smooth scales; slightly indented muzzle; pectorals edged in blue.

Possibly, although confusion is hardly possible, Dactylopterus volitans , Flying gurnard.

Alimentation

Carnivorous, the striated gurnard feeds on animals, in particular small crustaceans, but also molluscs, worms and fish, which it finds by searching the mud with its rostrum. It relies on its pectoral rays, which it uses as legs, but which are also detectors of prey, equipped at the ends with numerous sensory receptors. In summer, it can consume organisms in open water.

Reproduction

Breeding takes place between winter and early spring and sometimes early winter. The eggs, then the larvae * are planktonic *. After this phase, the juveniles migrate towards the bottom, approaching the coasts. The male-to-female ratio is typically 1: 1.
The sexual maturity of males is reached at the age of 2 years and that of females at the age of 3 years. The lifespan of females appears to be longer than that of males, which shows sex-differentiated mortality.

Associated Life

The copepod Neobrachiella impudica (von Nordmann, 1832) is known to parasitize striated gurnard, in particular at the level of the internal part of the operculum *.

Various Biology

All gurnards utter grunts produced by muscle contraction of their gas bladder which then vibrates. Depending on the depth, these sounds vary in tone and intensity.
When disturbed or when it feels threatened, the gurnard deploys its pectorals: it can thus make short “flights” while leaving the bottom.
It is estimated that a striped gurnard can live up to 18 years.

Further Information

Gurnards are often sold as red mullet, although the quality of their flesh is lower than that of true red mullet.
Not very shy, if you do not make sudden movements, the gurnard is quite easy to approach.