Blue-spotted Cornetfish

The bluespotted cornetfish grows to a length of 1.6 m (5.2 ft), but the average is around 1 m (3 ft 3 in). It is notable for its unusually long, slender body shape. It has a tubular snout, large eyes, and a long tail filament lined with sensory pores that may help with detecting prey. Its body is tinted blue- to greenish-grey with two thin blue stripes or lines of dots on the back and lighter on the front. Its body pattern changes to a broad-banded pattern at night for camouflage.

It is widespread in the tropical and subtropical waters of the Indo-Pacific as far north as Japan and east to the west coasts of the Americas, including Panama and Mexico's Sea of Cortez and the Red Sea. In 2000, its presence was reported in the Mediterranean Sea off Israel. In the past 20 years, this species experienced a population explosion in the Levantine Sea and a rapid spread westward, reaching the westernmost sectors of the Mediterranean and as far north as the Gulf of Lions by 2007. At this point, it has been recorded in all Mediterranean sub-basins and is now very common in the eastern part. F. commersonii is now considered an invasive species in the Mediterranean Sea because of its rapid development to reproductive stage and its detrimental effect on native fish populations. This is known as the Lessepsian migration which is an event that occurs when fish, usually fish from the Red Sea "migrate" to the Mediterranean Sea from the Suez Canal. The fish in the Mediterranean are all descended from a small number of ancestors, possibly as a result of a single invasion event, and are not as genetically variable as their conspecifics in the Red Sea.