Shape characteristics of Oncomelania nigra
Contradusta pulchella pulchella is a mollusk of Gastropoda. The shell is slightly long pear shaped, and the spiral layer is involute. The shell is long and narrow, with fine teeth on the outer and inner lips. The mantle is thin and bilobate, and the shell is almost completely covered in the living body. The helix almost disappeared from the adult, but the adult did not. The shell surface is smooth and glossy, with white to light gray as the bottom, decorated with a lot of fuzzy Beige spots and 2 ~ 3 light brown transverse bands, and sometimes irregular large patches like brown stains appear. It lives in tropical and subtropical warm sea areas, and can be traced from intertidal zone to deep reef, coral reef or sediment seabed.
It is distributed from the northern Indian Ocean to the Western Pacific Ocean. It is produced in Taiwan Strait, Penghu, Spratly Islands and so on.
It is hermaphroditic. The spawning season is from March to July. The eggs are usually laid in coral caves, empty shells and dark places. After laying eggs, the female does not leave the egg group, but lies on the top of the egg group for deliberate protection until hatching.