Fig. 2 in Phenotypic plasticity associated to environmental hypoxia in the neotropical serrasalmid Piaractus mesopotamicus (Holmberg, 1887) (Characiformes: Serrasalmidae)

Fig. 2. Photographs showing increases in size of the three morphological traits of Piaractus mesopotamicus analyzed exposed to extreme hypoxia: (a) lower lip, (b) maxillary, and (c) opercular valve. White arrow indicates the area where the expansion of dermal tissue occurred.