Tucanoichthys tucano, neurocranium of specimen TCWC 20316.01, 14.4 mm SL, c&s. A. Ethmoid region in dorsal view. Circular inset shows close up of nasal on left side. B. Ethmoid region in ventral view. Margin of vomer outlined by thin white line. C. Posterolateral part of otic capsule, left side in dorsal view. D. Posterolateral part of otic capsule, right side in ventral view. Otoliths highlighted in light grey, margin outlined by thin grey line. Margin of auditory foramen ventral to lapillus outlined by thin dashed white line. A and B share single scale bar. Abbreviations: Asph, autosphenotic; Ast, asteriscus; BL, Baudelot’s ligament; Boc, basioccipital; Ec, epiotic; Exoc, exoccipital; Fr, frontal; Lap, lapillus; LE, lateral ethmoid; Me, mesethmoid; Na, nasal; Osph, orbitosphenoid; Pa, parietal; Pro, prootic; Psph, parasphenoid; Pt, pterotic; Ptsph, pterosphenoid; Sag, sagitta; Soc, supraoccipital; TrC, trabecula communis; Vo, vomer.

  Part of: Mattox GMT, Conway KW (2021) Osteology of Tucanoichthys tucano Géry and Römer, an enigmatic miniature fish from the Amazon basin, Brazil (Teleostei: Characiformes: Characidae). Vertebrate Zoology 71: 645-667. https://doi.org/10.3897/vz.71.e71886