start stage end stage corpuscles of Stannius zebrafish_anatomy ZFA:0001200 Islands of eosinic cells found on the lateroventral surface of the kidney. Function is thought to be that of the parathyroid gland in other vertebrates, which are lacking in fishes. These cells secrete hypocalcin (teleocalcin) to regulate calcium metabolism. TAO:0001200 portion of tissue segmentation:20-25 somites adult