Alteroida

Alteroida is a genus of small, air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Helicarionidae. These snails are native to various regions in Southeast Asia, including Indonesia, Malaysia, and the Philippines. The genus Alteroida was first described by the malacologist Alan Solem in 1984.

The shell of Alteroida snails is typically small, usually measuring less than 10 millimeters in diameter. The shell is usually discoidal, meaning it is shaped like a flattened disk, and is usually dextral in coiling, meaning the shell coils to the right when viewed from above. The shell surface is usually smooth or finely striated, and the color can vary from light brown to dark brown, often with a pattern of darker spiral bands.

Alteroida snails are known for their unique reproductive anatomy. Like other members of the family Helicarionidae, they possess a love dart, a calcareous or chitinous dart that is used during mating to deliver mucus that may have an effect on the partner's reproductive system. This feature is a subject of interest in the study of snail reproduction and evolution.

The habitat of Alteroida snails typically includes humid, shaded environments such as forests and gardens. They are known to feed on a variety of organic matter, including decaying plant material and fungi. Due to their small size and secretive nature, these snails are not well-studied, and much remains to be learned about their biology and ecology. Conservation status of most Alteroida species has not been evaluated, but habitat loss and degradation pose potential threats to their populations.