ROCK LOBSTERS

HABITAT

ANATOMY

LIFE CYCLE

DISTRIBUTION

Anatomical Features of Red Rock Lobster

External features

External features and their function

External Feature

Function

Eye

Compound eyes at the tip of the eye stalks.

Antennae

Long "feelers" that can be rotated around to fend off predators.  They also have some sensory function.

Antennules

The short slender appendages are capable of detecting food (tasting), danger, and pheremones.

Legs

5 pairs of legs used for walking and feeding.

Carapace
(or cephalothorax, the head & thorax)

Protection of vital organs such as the liver, stomach, gonads, gills and heart by the exoskeleton case.

Tail (or abdomen)

Consisting of 6 separate, moveable parts, plus the tail fan (telson and uropods). The main muscle for movement (swimming) away from danger. Under the tail are paired feather-like appendages (pleopods).

External features - location and identification

Internal features

Internal features - location and identification

Internal features and their function

Internal Feature

Function

Mouth

The mouth is for the ingestion of food. It has a series of appendages associated with it that help bring the food to the mouth and crush it before ingestion.

Gills

The gills, which sit under the carapace at the base of each leg, are used for the uptake of oxygen from the water and release of carbon dioxide.

Heart

The heart pumps the blood around the body of the lobsters.

Gonad

The gonad produces eggs or sperm for reproduction.

Hepatopancreas

(or liver)

The hepatopancreas (or liver) produces the digestive fluids which break down the food that is eaten.

Digestive track

The digestive tract is used to absorb the nutrients from the food.

Anus

The waste products of digestion are excreted through the anus.

Sexual Differences

Difference

Function

Genital

pores

Females. Positioned on the base of the 3rd walking leg for females so the eggs are extruded and pass through the sperm package the male deposits on her abdomen before attaching to the pleopods

 

Males. Positioned on the base of the 5th walking leg for males so the sperm package is deposited below the female genital pores

Grooming claw

Present on the 5th leg of the female only, it is used for grooming the eggs when they are attached to the pleopods

 

Not present on the males

Pleopods

Females have biramous (or double) pleopods. The innermost branches of the pleopods are covered with long hairs for the attachment of the eggs. The female keeps the eggs aerated by slowly beating her pleopods.

 

Males have single pleopods

© NZ Rock Lobster Industry Council Ltd