Oral disks of (A) paratype of Panaque. nigrolineatus laurafabianae, 268 mm SL, showing well-developed patches of papillae immediately interior to each premaxillary and dentary tooth row and (B) P. nigrolineatus nigrolineatus, 267 mm SL, with much smaller, more reduced patches. Figure 3 in Ortega-Lara & Lujan 2020.
