Kitagawa Tetsuro, Hosoya Kazumi
Faculty of Agriculture, Kinki University, Nakamachi, Nara 631-8505, Japan.
Zoolog Sci. 2015 Oct;32(5):435-7. doi: 10.2108/zs140296.
An anomalous individual with an adipose fin-like projection was discovered during seedling production of Biwa rock catfish, Silurus lithophilus (Teleostei: Siluridae). The external shape of the projection resembled an adipose fin, but soft rays were clearly observed within it. The projection was proximally supported by a series of pterygiophores and by 14 soft rays. The projection can be explained as: I, homologous with a primitive adipose fin, which occurred as a result of localized ontogenetic reversion; II, an extra fin that occurred as a result of abnormal expression of a regeneration mechanism; III, a remnant of a dorsal fin and/or a second dorsal fin; and IV, an inversion phenomenon of the polarity in the formation process of the anal fin.
在琵琶湖石鲶（Silurus lithophilus，硬骨鱼纲：鲶科）的鱼苗生产过程中，发现了一尾具有脂鳍状突出物的异常个体。该突出物的外形类似于脂鳍，但其中清晰可见软鳍条。该突出物近端由一系列鳍担骨和14根软鳍条支撑。对于该突出物可作如下解释：I，与原始脂鳍同源，是局部个体发育逆转的结果；II，由于再生机制异常表达而出现的额外鳍；III，背鳍和/或第二背鳍的残余；IV，臀鳍形成过程中极性的反转现象。
