Karin Mahlfeld, David Roscoe, Frank Climo
iNaturalist
The infamous Potamopyrgus antipodarum is the larger species in this image. If you google Potamopyrgus antipodarum you will see that this little freshwater species causes a lot of trouble overseas. The smaller, slimmer species in the image is Potamopyrgus oppidanus, a Wellington endemic species! It is listed as critically endangered on the IUCN red list. Its habitat is a little stream covered in Tradescantia before it enters a pipe under the road. The stream gets cleaned out in heavy rain and the population has taken a hit after the last heavy rainfalls in November. It would be useful to keep an eye on the population dynamics of P. oppidanus. Any volunteers?
I think its some sort of sea snail. Found it in the shallow part of a small pond. They all had two openings on the shell, one in the front and one in the back. An inch long in length and dark purple in color. And a sort of green slime inside