New Zealand screwshell (Maoricolpus roseus)
Have you see this marine pest in NSW?
Key features
New Zealand screwshell
New Zealand screwshell M. roseus - faded with age
M. roseus blanketing ocean floor
Habitat
Sandy or muddy surfaces; intertidal to subtidal zone.
Current locations
- NSW: Eden and possibly further north
- Found in Tasmania and Victoria
Impacts
- Blankets the ocean floor
- Has been blamed for local extinctions of native Australian screw shells
Similar native species
Native Screw Shells
Native screwshell, Gazameda spp.
Key Features:
- Shorter shell, up to 56mm length
- Lighter colouration
- Narrower shell with ridges of fine beads
Habitat: inner shelf at depths of 8 - 140 metres.
Mud Whelk
The native Mud whelk, Velacumantus australis
Key features:
- Stout shell, 35mm average length
- Dirty grey colour
- Rough spialled shell
Habitat: on mud flats between mangroves.
Hercules Club Whelk
Hercules Club Whelk, Pyrazus ebeninus
Key features:
- Longest local mudwhelk species, 75mm average length
- Dark brown shell
- Flaring lip, usually black in colour
Habitat: in mangrove mud; drag their shells behind them, leaving a myriad of tracks in the mud.
If you see this pest in NSW, please report it immediately
- Note the exact location
- If possible take a photo and/or collect a sample
- Freeze smaple in a plastic bag
- Report your sighting
Photograph credit: Native species: Holly Harlow, Australian Museum (Gazameda spp); Patty Jansen Australian Shells (others).
NZ Screwshell: CRIMP, CSIRO Australia