Rabbit Snail (Tylomelania Sp.)

Rabbit snail, Elephant snail, Yellow spotted rabbit snail, Mini yellow rabbit snail, Poso snail

Habitat

All species of the genus Tylomelania come from the Indonesian island - Sulawesi (Celebes), from the system of tectonic lakes there and for the most part, they are endemic species (34 out of 75 described so far). These lakes are located in a mountainous area surrounded by steep hills and tropical rainforests. The habitat is formed by Lake Poso, the Malili Lake system (larger Matano, Mahalona, Towuti and smaller: Lontoa, Masapi) and adjacent rivers and streams (including Poso, Tominanga, Larona). These lakes are connected directly (by rivers) or indirectly (underground drains). All lakes are oligotrophic, which means they practically do not contain any organic and nutrient components. They also have a high transparency, a water temperature of 27-31°C, and the same amount of dissolved oxygen at each level (even at the bottom). This unique phenomenon is a merit of the natural phenomenon occurring in these waters - specific vertical currents that constantly stir the water.

Appearance

The variety of species among Tylomelania is directly due to their natural habitat - mainly the substrate they occupy and the type of waters they come from (standing or flowing). The snails available for sale, unfortunately, do not constitute one species, and even the names given do not guarantee that we are dealing with that species. Of course, it is possible to distinguish individual species from each other, but this can not be determined only by external characteristics: the size of the snail, the color of its body and shell, the shape of the shell, the shape of the cap, or the occurrence of ribbing. The best way seems to be the analysis of the radula with teeth and the mature embryo. Therefore, in this article, the genus Tylomelania will only be described generally. The size of the shells of these snails ranges from 1cm (Tylomelania Neritiformis) to 11.7cm (Tylomelania Patriarchalis). It is usually yellow-brown, yellowish-green, reddish-brown, brown or black in color, conical or ovate in shape with a pointed tip, with 2 (Tylomelania Inconspicura) to 13 (Tylomelania Gemmifera) turns. The shell can be completely smooth, partially grooved or completely notched (axial ribs, straight or wavy, all over the surface). In all mature species, the tip of the shell is heavily corroded. The lid (operculum) can be almost round, ovate or more or less diamond shaped. The body (foot and head) is gray to black with white or yellow dots, spots, stripes (Malili Lake system) or light - yellow, orange, white - contrasting with the color of the shell (Lake Poso). The antennas are often striped, especially in the Malili Lake system. The head is wide, with a clearly visible mouth cavity from below. The antennas grow from the base of the head - on both sides. The eyes are small and black, located at the base of the antennas. The foot is small. Basically, there are no visible dimorphic features. In some cases, the female is much larger than the male: Tylomelania Bakara, Tylomelania Kruimeli, Tylomelania Mahalonensis, Tylomelania Masapensis, Tylomelania Sarasinorum.

Temperament

Snails of the Tylomelania genus are peaceful inhabitants of the aquarium. They can be successfully kept with peaceful fish and shrimp. We avoid their natural predators: fish feeding on crustaceans and crabs. These mollusks do not eat plants, they can dig up the substrate. They are active both during the day and at night.

Aquarium

When choosing an aquarium for them, we should primarily be guided by the surface area of the bottom of the tank - the larger, the better. As for the substrate - it should be tailored to the specific species, which complicates the matter. In natural conditions, these snails are found on soft substrates (sand, tiny gravel, silt), or on hard surfaces (stones, rocks, trees, roots). It is therefore best to put all these elements in our aquarium - then we can be sure that our snail will be happy. Plants are not required. The lighting should be diffused, hiding places are essential. When arranging the tank, attention should be paid so that all the gaps are of the appropriate size so that our charges do not jam in them. Covering the aquarium is not necessary - due to the small foot and heavy shell, these snails are reluctant to climb. The water in the tank should be crystal clear, very well oxygenated.

Reproduction

Ovoviviparous, dioecious species. Fertilization is internal. The male equipped with a copulatory organ (appendage) fertilizes the female, with the sperm being deposited in a semen tank (it can be stored there for a longer time and used when needed). After fertilization, the female releases embryos (their number and size depend on the specific species) to a special chamber - the so-called brood pouch. These embryos remain in egg envelopes from which they draw nutrients. The embryos mature for about 4 weeks inside the female's body and have a fully formed, small shell. At hatching, young snails still remain in the egg envelope, which the female removes shortly. Reproduction is ongoing, the next, largest embryos are constantly released by the female - that's why these snails reproduce quite quickly.

Food

In natural conditions, the food source of snails from the Tylomelania genus depends on the substrate on which they reside. Snails residing on hard substrates primarily feed on algae (mainly diatoms), those from soft substrates mostly feed on detritus (dead organic substance). In the aquarium, they seem to be not too picky and are happy to consume fresh vegetables, food intended for fish or crustaceans (sinking).