“…In the rhombencephalon, which is divided in rhombomeres (r0‐r8) following the neuromeric model, all the cholinergic neurons of the motor nuclei (trochlear nucleus, in the isthmic region or r0; trigeminal motor nucleus, in r2 and r3; abducens nucleus, in r5; facial motor nucleus, in r6; glossopharyngeal motor nucleus, in r7; and vagal motor nucleus, in r8) were Isl1‐ir (Figures 3m–v, 4k–o, 5i–o, 9c,e–g, and 10a–c). In contrast to chondrostean and holostean fishes, cladistians possess a peculiar and unique group of cholinergic neurons in the midline of r8, the nucleus medianus magnocellularis (Kenemans, 1980; López et al., 2013), whose neurons coexpress Isl1 (Figures 3a,s,t and 10c). Additionally, the most caudally located cholinergic cell group, the spino‐occipital nucleus (so), presented Isl1 immunoreactivity as well (Figures 3u, 4o, 5o, and 10b).…”