Metasepia tullbergi

Species of cuttlefish

The paintpot cuttlefish (Metasepia tullbergi) is a small, poorly researched species of cuttlefish found in the Indo Pacific, between Japan and Hong Kong. It is one of the two species classified in the genus Metasepia. Metasepia cuttlefish are characterized by their small, thick, diamond shaped cuttlebone, and distinctive body coloration. The World Register of Marine Species lists the paintpot cuttlefish under the genus Ascarosepion; within this genus it is grouped with 13 other species, such as the broadclub cuttlefish, the reaper cuttlefish, and the giant cuttlefish. This reclassification renders the genus Metasepia obsolete

Paintpot cuttlefish are a slow moving, bottom dwelling species in the neritic zone found at a depth of 20 to 100 meters in subtropical climates. Their mantle (the "body") is about 70mm long; it has a broad, oval shape with 10 to 13 pores on each side. Their fins are joined in the back of the animal with arms located on the opposite end of the squid at the head, like all coleoids. Their arms typically have 10 to 12 rows of shorter suckers followed by larger ones and then tapering in size through to the arm tip. Their adult weight ranges from 30 to 40 grams. The hectocolytus (male sperm) is present in the left ventral arm. Unlike other species of cuttlefish, Metasepia have a cuttlebone that is much smaller than their mantle. Characteristic of cephalopods, chitin is present as a thin film covering the entire dorsal surface of the cuttlebone and tapers into a sharp point on the dorsal corner.

The paintpot cuttlefish is typically found in the subtropical Indo Pacific, in the seas surrounding Japan, China and Korea. Sightings have been recorded in Japan from southern Honshu, the Sea of Japan, Yellow Sea, East China Sea to Taiwan and Hong Kong, South China Sea, the Philippines and the Gulf of Thailand. In these regions, the paintpot cuttlefish is found in the continental shelf between 20 and 100 meters deep on sandy to muddy substrate or on sea pens in rocky substrate.