Description:

The thick-walled shell of this Tylomelania species is up to 5.5 to 6 cm long and about 1.5 cm wide.It has 12 to 13 whorls, the older animals' apex is strongly corroded and in some cases there are only a few fragments left. The suture is very pronunced. The shell also shows a noticeable axial sculpturation.The body whorl shows spiralling lines ending in the aperture.

It has a round operculum with a central nucleus (multispiral). It is significantly smaller (about 0.5 cm) than the aperture, which can reach an average of 0.9 cm in height and 0.7 cm in width for the 6 cm long animals.Its body color is white with a dark horizontal pattern. The eyes are located at the bases of the straight tentacles. Its mouth part is rather long and looks soft. 

Range:

Please refer to the General Description. 

Habitat:

This Tylomelania species originates from Lake Poso on Sulawesi, it lives there 7 to 20 m deep on soft substrate, however, it can also be found in shallower waters from time to time. 

Reproduction:

Please refer to the General Description 

Food:

In the aquarium it likes to dig in the mud, eats powdered food and after some time it even crawls towards food tablets purposefully. Vegetable dry food as well as dry food with animal proteins is accepted. I haven't been able to see it feed on carrion, mosquito larvae or beef heart yet.Like all snails, it eats all day long as well as during the night if there is food, with the exception of a few minutes' rest. Usually, as there is no food during the night, it rests then. I would not describe it as being nocturnal.

Behavior in the aquarium:

This Tylomelania species is, if caught from the wild, rather jumpy at first. Bright tank light seems to bother it a lot, and it likes retreating to shadowy areas. After 4 weeks' adaptation time it seems to do well in the new surroundings and crawls freely also in the bright zones. Quite seldomly it flinches at occasional shadow changes of its environment.It was interesting to watch its initial reactions to mechanical stimuli or rather, bothersome dwarf shrimp. As soon as it perceives a tactile stimulus it stomps its foot on the ground and thus stirs up a cloud of dust. After that it retreats into its shell very quickly, body and foot.

The weight of its shell enables it to do so without losing balance. After 5 to 6 weeks this strong reaction had weakened a little, however, the consequence was that it hardly ever came out of its house at all. That's why I had to take the shrimp out of the tank. Since I keep it with other snails and without shrimp this behavior has totally disappeared.When searching for food they occasionally nip a con-specific's foot. The stomping does not happen, the other snail only retreats its body into the shell – however, only as far as is necessary to get out of reach of the radula.A further interesting characteristic was that the snails pressed their heads together during the adaptation time.During the first week after putting them into the tank the snails could be perceived looking for each other and then pressing their heads together and remaining in this position for at least 20 minutes without movement.After they had explored the tank this behaviour stopped

The aquarium:

The snail's requirements are clear. It is a soft-substrate dweller and thus should find sandy or muddy ground in the tank. After the adaptation time it can never be found on hard substrate.It needs wood and leaves, dark corners, there should not be large numbers of dwarf shrimp or fish present. It can be well socialized with other Tylomelania species, and there were also no problems with river snails from its habitat or clams.Feeding several times a day is compulsory.

When already adult at the time of being caught the females often release young snails, depending on the enviroment, every two to four weeks for weeks on end. The young snails are nearly 0.5 cm in size. Within the first two months these young snails grow by about 0.2 cm.Depending on the stocking the tank should be 60 cm, better 80 cm in length as a rule. A Hamburg Mat Filter (HMF) is adequate. Plants are not necessary, but do not bother these snails either, given that the snail still has enough room to move.

The pH value of Lake Poso is between 7,5 and 8,5. Unfortunately I do not know the hardness, however, the strongly corroded apices do not suggest hard water. They do very well in my soft water (GH 0, KH 2 and pH 7 – 7.5).

I'd like to thank Thomas von Rintelen, Humboldt University Berlin, who took the time to give me further information on these snails as well as text documents of dissertations.

This page was actualized on August 24, 2008

Author : Alexandra Behrendt

Translator: Ulrike Bauer