Panulirus versicolor grows up to 40 centimetres (16 in) long, but is typically no more than 30 cm (12 in). It has no claws, two spiny rostra over the eyes, and two pairs of large antennae, like all spiny lobsters. The first pair of antennae are double ended, the second hard and spiny, both are usually white.

Blue Spiny Lobster (Panulirus Versicolor) is a species of Spiny Lobster that lives in tropical reefs. Other names it’s known by include: Painted Rock Lobster, Common Rock Lobster, Bamboo Lobster, and Blue Lobster. The Blue Spiny Lobster or Painted Rock Lobster is one of the three most common varieties of Spiny Lobster in Sri Lanka.