Mud-dwelling giant ship-worm that lives head down in a tusk-like tube found alive for the first time in the Philippines.

The newly discovered creature has astonishing features with three feet long and gleaming black body with a pink, fleshy appendage looks like the creepy entrails of an alien from a nightmarish movie.

Scientist had studied before this rare species of worm but no living specimen had been examined until now.

According to a US science journal, the shipworm can reach up to 1.55m (5ft) in length and 6cm (2.3in) in diameter.

The team of scientists from the US, the Philippines and France collected five giant shipworms in Mindanao in a marine bay.

The queerest characteristic of the worm is its habitat as it lives incased in a tusk-like hard shell, submerged head-down in mud, which it feeds on.

This long, slimy black creature is actually a bivalve, which is the same group as clams and mussels. Except for this anomalous species the rest of the members of its group are usually much smaller and burrow and feed on rotting wood.

According to the Proceedings of the National Academy of Sciences of the United States of America (PNAS), the "rare and enigmatic species", also known as Kuphus polythamia, is the longest living bivalve known to man.

The specimen has a much smaller digestive system than other shipworms and feeds on mud and marine sediment using a type of bacteria.

The animal creates its own hard tube shell, made of calcium carbonate, by secreting a substance.

It also creates a hard cap to cover its head, which is re-absorbed by the giant shipworm when it wants to grow and burrow further into the mud, researchers said.