Journal of the Marine Biological Association of India

Occurrence and biology of the solitary ascidian Ascidiella aspersa in Tamil Nadu coastal waters.

Volume 34 Issue 1&2

A. K. Nagabhushanam and P. Krishnamoorthy

Abstract

The ascidian which normally occurs in temperate waters, was found in the Madras area and studied by culturing it in the laboratory. The external and internal characteristics have been studied, as well as the development from the fertilized egg, the tadpole-larva and the young juvenile after its attachment to the substratum.

The tolerance to salinity, temperature and pH have been studied. Besides, the food and feeding preference of the attached adults have been noted. This species grows 8 to 10 mm per month on the average; it becomes sexually mature when it is 5-6 cm in total length, which is attained when th« animal is approximately 6-7 months old. In the laboratory, the animals do not live for more than 15 months or after they reach 14 cm in overall length; an individual during its 1 ½ years of life-span releases eggs thrice.

Date : 31-10-1992