New Zealand Half Crab

Petrolisthes elongatus (H. Milne Edwards, 1837)

This half crab is another introduce invasive species that can be found around Tasmania in ever expanding ranges. Locally this crab is just about everywhere you can lift up a rock along Tomahawk Beach and around Tomahawk Island.

This crab often drops legs as an escape mechanism regrowing them over time like how lizards drop their tails.

This is an invasive species within Tasmania and as such it is an offence to use these crabs as bait or to move them around despite the fact, they are now readily established state-wide.

How to identify Petrolisthes elongatus?

With an overall flattened appearance it varies in colour with mottled blues, greens, and browns. The carapace is slightly longer than it is wide and the rostrum broadly triangular and extends past the eyes with the long whip like antennae to the outside of the eyes. With large, flattened chelae (claws) and looks to only have three walking legs although it does have another that is tucked away at the rear into the abdomen flap

What habitats does Petrolisthes elongatus live in?

Can be found in intertidal areas under rocks and out to depths of around 12m

What is the distribution of Petrolisthes elongatus?

Native to New Zealand it is now found in Victoria and around Tasmania

How big does Petrolisthes elongatus grow?

Up to around 18mm

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Provided by The Atlas of Living Australia
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Disclaimer: A lot of work goes into trying to identify and ensure accurate identifications are made and that the listed Descriptions, Sizes, Habitats and Distribution information is as accurate and valid as possible. Unfortunately, information in this arena is ever changing and as such no guarantee can be offered that it is correct or currently valid as a result the information is provided as a guide, and it is always suggested that you do a little research to ensure you have the latest and most accurate information. View the reference's or bibliography I welcome any feedback and comments on the information provided.

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