Latin name

Tetrapturus belone

Other names

French: aguglia impériale; Italian: acura imperiale, aguglia pelerana.

Identification

Body powerful, elongated, strongly flattened from sides: snout in form of elongated, lance-shaped, rounded in cross-section rostrum, which length (from its apex to eye) is about 18% of body length. The upper profile of the head is smooth, without a sharp rise at the occipital part. The gill flaps are closed on, but are not attached to the intergill space. There are no gill rakers on the gill arches. Dorsal fins are two, located close to each other: the first with a long base and a high, rounded front blade, the height of which is slightly higher than the height of the body in its front part. The height of the fin decreases smoothly until about the 10th ray, the height of the subsequent rays is the same almost until the last ten rays, the length of the last rays decreases smoothly. The second is with a short base, shifted closer to the caudal peduncle. The anal fins are two: the first with a slightly longer base than the second, with a high, pointed front blade. The second is equal in length and height to the second dorsal fin and shifted slightly forward relative to the latter. The pectoral fins are short (their length is 10-13% of the body length) and wide with sharp apexes, tightly pressed to the sides of the body. The pelvic fins are long (less than twice as long as the pectoral fins), thin, and can hide in a deep groove on the belly. The caudal peduncle is strongly flattened laterally and has well-developed paired keels. The anal opening is located in front of the beginning of the base of the first anal fin, at a distance almost equal to the height of this fin. The lateral line is clearly visible, with a curve above the pectoral fin. The body is covered with elongated, pointed, thick bony scales with 3 to 5 serrations at the end. The body is bluish-gray, almost black on the back; the belly is silvery-white without spots or stripes on the fins.

Distribution

Mediterranean Spearfish in its distribution is limited to the waters of the Mediterranean Sea: it occurs most often in its central part, along the coasts of Spain, Italy (in the waters of Sicily, near Naples, in the Strait of Messina, near Palermo, in the Gulf of Naples, near the coast of Venice), in the Ligurian Sea, near Malta, Majorca, in the Adriatic Sea, near the coast of Croatia, but does not enter the Aegean and the Black Sea. There is no data on the habitation of adults in the Ionian Sea and along the coast of Israel.

Habitat

Marine pelagic fish, lives mainly in the upper layers of the pelagic zone above the thermocline (to a depth of 200 m from the surface). They do not form large flocks, but most often occur in pairs.

Size

The greatest length is 240 cm with a weight of 70 kg. Usually, the basis of commercial catches are fish about 2 m long and weighing 10-30 kg.

Life history and Behavior

The spawning season is probably in the winter-spring period.

Food and feeding habits

It feeds on pelagic objects - sardine, various representatives of flying fish, mackerel, mackerel, coriffenovye and sargan.

Reproduction

According to ichthyoplankton surveys around the Strait of Messina, the discharged eggs have a diameter of 1.48 mm and a yellow-green fat drop. The incubation period lasts several days.