Facts About the Spiny Lobster (Rock Lobster)

Brown spiny lobster
Brown spiny lobster. Debru, Jacques / Getty Images

A spiny lobster is any lobster in the family Palinuridae, which includes at least 60 species. These species are grouped into 12 genera, which include Palinurus, Panulirus, Linuparus, and Nupalirus (word play on the family name).

There are numerous names for the spiny lobster. Commonly-used names include the rock lobster, langouste, or langusta. It is also sometimes called a crayfish or crawfish, even though these terms also refer to a separate freshwater animal.

Fast Facts: Spiny Lobster

  • Scientific Name: Family Palinuridae (e.g. Panulirus interruptus)
  • Other Names: Rock lobster, langouste, langusta, sea crayfish, furry lobster
  • Distinguishing Features: Shaped like a "true" lobster, but has long, spiny antennae and lacks large claws
  • Average Size: 60 cm (24 in)
  • Diet: Omnivorous
  • Life Span: 50 years or more
  • Habitat: Tropical oceans worldwide
  • Conservation Status: Depends on species
  • Kingdom: Animalia
  • Phylum: Arthropoda
  • Subphylum: Crustacea
  • Class: Malacostraca
  • Order: Decapoda
  • Fun Fact: Spiny lobsters make a rasping sound using friction at the base of their antennae.

Description

The spiny lobster resembles a "true" lobster in its shape and hard exoskeleton, but the two types of crustacean aren't closely related. Unlike true lobsters, spiny lobsters have extremely long, thick, spiny antennae. They also lack large claws or chelae, although mature female spiny lobsters have a small claw on their fifth pair of walking legs.

The average size of a mature spiny lobster depends on its species, but they may exceed 60 centimeters or 2 feet in length. Specimens of many spiny lobster species are red or brown, but some spiny lobsters have mottled patterns and display vivid colors.

Some species of spiny lobster are colorful.
Some species of spiny lobster are colorful. DigiPub / Getty Images

Distribution

Spiny lobsters live in tropical oceans worldwide. However, they are most commonly found in the Caribbean and Mediterranean, in coastal waters off Southeast Asia and Australia, and off the coast of South Africa.

Behavior

The spiny lobster spends most of its time hidden within a rocky crevice or reef, exiting at night to feed and migrate. During migration, groups of up to 50 spin lobsters move in single file, keeping contact with each other with their antennae. They navigate using scent and taste, as well as through their ability to detect the Earth's magnetic field.

Reproduction and Life Cycle

Spiny lobsters reach sexual maturity when they reach the necessary size, which depends on water temperature and food availability. The average age of maturity is between 5 and 9 years for females and 3 and 6 years for males.

During mating, males transfer spermatophores directly into the female's sternum. The female spiny lobster carries 120,000 to 680,000 fertilized eggs on her pleopods for around 10 weeks until they hatch.

Juvenile painted spiny lobster
Juvenile painted spiny lobster. Hal Beral / Getty Images

Spiny lobster larvae are zooplankton that do not resemble adults. The larvae feed on plankton and go through several molts and larval stages. In the case of the California spiny lobster, 10 molts and larval stages take place between hatching and reaching the juvenile form. Juveniles sink to the bottom of the ocean, where they eat small crabs, amphipods, and isopods until they are big enough to take larger prey.

It is difficult to gauge the age of a spiny lobster because it gains a new exoskeleton each time it molts, but the animal's lifespan is believed to be 50 years or more.

Diet and Predators

Spiny lobsters are omnivorous, eating live prey, decaying matter, and plants. During the day, they stay hidden in crevices, but at night they may venture from crevices to hunt. Typical prey include sea urchins, snails, crabs, sea hares, mussels, and clams. Spiny lobsters have not been observed eating other members of their own species. The crustaceans navigate and hunt using senses of smell and taste.

Humans are the spiny lobster's most significant predator, as the animals are fished for meat. The spiny lobster's natural predators include sea otters, octopuses, sharks, and bony fishes.

Sound

When threatened by a predator, the spiny lobster flexes its tail to escape backwards and emits a loud rasping sound. The sound is produced using a stick-slip method, like a violin. The sound emanates when the base of the antennae rubs across a file on the antennal plate. Interestingly, the spiny lobster can make this sound even after it molts and its shell is soft.

While some insects (e.g. grasshoppers and crickets) produce sounds in a similar fashion, the spiny lobster's specific method is unique.

Conservation Status

For most spiny lobster species, there is is insufficient data for conservation status classification. Of the species listed on the IUCN Red List, most are categorized as "least concern." However, the common spiny lobster (Palinurus elephas) is "vulnerable" with a decreasing population. The Cape Verde spiny lobster (Palinurus charlestoni) is "near threatened."

The most significant threat to spiny lobsters is over-exploitation by fisheries. Climate change and single catastrophic events also threaten some species, particularly if they live within a restricted range.

Sources

  • Hayward, P. J. and J. S. Ryland (1996). Handbook of the Marine Fauna of North-West Europe. Oxford University Press. p. 430. ISBN 0-19-854055-8.
  • Lipcius, R. N. and D. B. Eggleston (2000). "Introduction: Ecology and fishery biology of spiny lobsters". In Bruce F. Phillips & J. Kittaka. Spiny Lobsters: Fisheries and Culture (2nd ed.). John Wiley & Sons. pp. 1–42. ISBN 978-0-85238-264-6.
  • Patek, S. N. and J. E. Baio (2007). "The acoustic mechanics of stick-slip friction in the California spiny lobster (Panulirus interruptus)". Journal of Experimental Biology. 210 (20): 3538–3546. doi:10.1242/jeb.009084
  • Sims, Harold W. Jr. (1965). "Let's call the spiny lobster "spiny lobster"". Crustaceana. 8 (1): 109–110. doi:10.1163/156854065X00613