Biology of the Caribbean Spiny Lobster
Classification and Life Cycle of Panulirus argus
Panulirus argus is a member of the spiny lobster family. It is commonly known as the Caribbean spiny lobster and also as the Florida spiny lobster. It is a commercially important species and supports fisheries throughout the majority of its range.
Classification of the Caribbean Spiny Lobster
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Crustacea
Class: Malacostraca
Order: Decapoda
Family: Palinuridae
Genus: Panulirus
Anatomy of the Caribbean Spiny Lobster
The spiny lobster body plan follows that of all decapods and is made up of nineteen body segments. These segments can be grouped together into the cephalothorax (head and chest area) and abdomen.
The carapace, that protects the cephalothorax of the lobster, is covered in forward pointing spines that give the family their name. A pair of prominent spines, ‘horns’, protrude over the eyes. The species has two sets of antennae, one slender pair, and one pair that are longer than the body and covered also in spines. Most noticeable about the spiny lobster is the lack of claws or pincers usually seen on lobsters, they have five pairs of legs absent of pincers that instead end in dactyls.
The abdomen is smooth and the tail fan consists of five appendages; four uropods surrounding a central telson.
Their coloration is varies from light grey to deep red and brown and they are mottled with darker spots. They have large yellow or white ocelli (eyespots) on the second and sixth tail segments with smaller ones scattered along the abdomen. Panulirus argus can reach a maximum length of 45cm.
Life Cycle of the Caribbean Spiny Lobster
The Caribbean spiny lobster has a life span of about 20 years and a maximum span of 30 years. They typically reach maturity in 2 and a half years.
There are 5 phases in the life cycle of Spiny Lobsters :
- Oceanic Planktonic Phase: Phyllosome larvae float for months in the water column. They are carried great distances by the currents before settling and metamorphosing into pueruli.
- Swimming Postlarval Phase: Free-swimming pueruli do not feed. They migrate to shallow in-shore habitats such as mangroves and seagrass, where they settle, molt and metamorphose into juvenile spiny lobsters.
- Early Benthic Juvenile Phase: Early juveniles are solitary and their coloration is well suited to their mangrove and vegetated habitats.
- Late Juvenile Phase: Late juveniles will stay in their inshore habitats for up to two years before migrating, as sub-adults, to near shore habitats.
- Adult Phase: Mature adults will habituate coral reefs, hiding in crevices during the day and emerging at night to forage and feed. Both juvenile and adult spiny lobsters are nocturnal feeders. Their diet includes bivalves, mollusks, gastropods and small crustaceans. They will migrate to off-shore waters when it is time to mate.
During the juvenile and adult phases the spiny lobsters will molt (shed their old exoskeleton and produce a new, larger, one) regularly. Molting frequency generally decreases with age in Panulirus argus and it take around 12 days for the new skeleton to harden enough so that it cannot be dented.
Reproduction of the Caribbean Spiny Lobster
Panulirus argus are highly fecund (fertile). During mating, the male spiny lobster will attach a spermatophore onto the belly of the female. Later, the female will spawn and attach her eggs to the underside of her belly, hence fertilizing them with the spermatophore left behind by the male.
The number of eggs that a female produces is directly proportional to her body size, therefore the larger, and inevitably older, the female, the more eggs she will produce when spawning. As cited by Moe in the 1991 book Lobsters: Florida, Bahamas, and the Caribbean, females with a carapace length of 3-3.5 inches can produce between 250,000 and 500,000 eggs and those with a length of 4-5 inches can produce between 1 and 2 million.
A Caribbean Spiny Lobster
|
More in Science & Nature
Latest Articles