In 2022, we published a great article by Thomas von Rintelen, which featured the diverse range of snails inhabiting Sulawesi lakes and rivers. In the article, Thomas also mentioned a number of species that are still waiting to be described. I definitely recommend reading it.

As a big snail fan, I particularly like Poso Lake because there are so many interesting and strange species there – and it doesn't help that many of them are undescribed and so similar! As part of our collaboration with Institut Mosintuwu, we are creating educational materials about the biodiversity of Lake Poso, and it forced me to do a bit of organizing in the photos and sort out all the known and unknown snails.

In this post, I will introduce the endemic species that you can encounter in Lake Poso (and nowhere else in the world). I believe it will serve as an enticement for you to visit Lake Poso, and most importantly, it will open your eyes – so little is still known about the biodiversity of Sulawesi!

Celetaia persculpta lives in places where the bottom is soft. It is constantly digging in the substrate and looking for something to eat – the undigested food leaves in the form of balls… the thin rolls next to it are from tylomelanias :-).
Miratesta celebensis and other instructive droppings :-). This snail, related to the ramshorn, lives only in a very small part of Lake Poso. This, together with the strange thick-walled shell and the high difficulty of maintaining it in aquarium, makes it a real rarity. This image tells us that we are once again dealing with an inhabitant of soft substrates.
Protancylus pileolus is also related to the ramshorn and very interesting. We find it exclusively on the shells of other snails (here Tylomelania kuli).
Gabbia sp., a smaller snail from hard substrates, is still waiting for its scientific description.
The genus Sulawesidrobia in Lake Poso is represented by 14 species. They are all miniature, mostly around 3 mm, and can be found on stones, plants, shells of other snails…

So far, only 4 species of Tylomelania have been described directly from Lake Poso. Here you have them all – and after them others without a scientific name that we more or less know from aquariums, or we don't know at all:

Tylomelania kuli.
Tylomelania centaurus.
Tylomelania toradjarum.
Tylomelania carbo.
Tylomelania sp. "Poso 1 – Orange".
This picture is the only one from aquarium, the others were taken directly in Lake Poso or on its shores.
Tylomelania sp. "Poso 2 – Yellow".
Tylomelania sp. "Poso 3 – Wood Black".
Tylomelania sp. "Poso 4 – White".
Tylomelania sp. "Poso 5 – Blue".
Tylomelania sp. "Poso 6 – Dark Brown".
Tylomelania sp. "Poso 7 – Yellow Striped".
Tylomelania sp. "Poso 8 – Yellow Mottled".
Tylomelania sp. "Poso 9 – Smooth Black".
Tylomelania sp. "Poso 10 – Light Shell Black".
Tylomelania sp. "Poso 11 – Thick Shell Black".
Tylomelania sp. "Poso 12 – Thick Shell Mottled".

This list of endemic snails of Lake Poso is far from complete. It is also possible that some of the different "types" listed above actually belong to the same species or are hybrids. We will continue to collect and process knowledge from the field and share it. We will also hopefully soon see scientific publications from more authoritative figures led by Thomas von Rintelen, the Sulawesi Keepers snail expert – we will also keep you posted…

Markéta Rejlková