On September 12, 1979, a black porgy, Acanthopagrus schiegeli (Bleeker), lacking the spinous dorsal fin was angled at a culture pond (16, 844m²) in the Yamaguchi Prefectural Naikai.Fisheries Experimental Station.The pond is connected to the sea by a water gate.
The deformed porgy, which seems to be a wild specimen, showed the following chracteristics: All spinous dorsal rays except the last one were lacking.Free interneural spines and the first interneural spine stuck to each other and were pushed forward, forming a kind of hump at the top of the head.Interneural spines generally found between the first and last interneural spines of the spinous dorsal fin were lacking.The first and second neural spines were slightly curved forward.The supraoccipital was not properly developed.Other anomalies were not observed.