Lake Poso 2024 – below the surface

As I informed you in a previous post, in May 2024 we spent four days on Lake Poso in the company of students and teachers from five local schools. It was therefore not a purely observational or photographic expedition. But that does not mean that we did not collect a lot of material that we can gradually share with you here or on YouTube.

Lake Poso is very diverse and also rocky :-). And truly full of life. Enjoy our selection of twenty photos that will bring you closer to this beautiful treasure of Indonesia.

Caridina ensifera are hard to miss if you are in the right place. Swimming among thousands of shrimps is an amazing experience!
Caridina longidigita on the underside of a submerged branch. The water here near the shore was definitely not stagnant and contained plenty of particles that these shrimps catch with their specially shaped “fingers”. Don’t miss the video we dedicated to this fascinating species.
The crab Sundathelphusa molluscivora was only described in 2008. Here it is in the company of the shrimp Caridina caerulea.
Parathelphusa sarasinorum is the most abundant crab species in Lake Poso.
Nymphoides cristata, underwater detail. This plant is non-native here, originating from South Asia. We recorded it in Lake Poso on a sandy shallow, it is not abundant.
Tylomelania sp. "Poso 11 – Thick Shell Black". This is how we have named the snail, which is very abundant in places, on previous expeditions. However, it does not yet have a scientific name.
This species was new to us too: in our list of snails from Lake Poso (see here), we can assign it the designation Tylomelania sp. "Poso 13 – Yellow Rocky". As the name suggests, it is found on rocks – and only where the water is very turbulent.
It's incredible how many snails feed on "bare" stones.
Miratesta celebensis (the big grey snail) is a unique phenomenon. Here in a slightly atypical environment, where it wandered from the soft bottom to the rocks.
Soft sandy bottom, typical snail habitat Celetaia persculpta.
A look into the deeper water reveals schools of ricefish and striking freshwater sponges, which are found in areas with stronger water currents.
A closer look at two different types of freshwater sponges. The large green ones use the light, while the lighter colored "donut-shaped" ones tend to be on the underside of rocks.
© Evan Gogani
Microworld: Tylomelania carbo and Caridina ensifera, but also the tiny snail Sulawesidrobia sp. and miniature moss.

… and we are still at the surface, look forward to what our underwater drone will show!

We are grateful to our partners who participated in or supported the expedition: Institut Mosintuwu, AKWB, MEGAZOO & Friends, Ostrava Zoo, EUAC, and individual donors.

Markéta Rejlková