https://onlinelibrary.wiley.com/doi/abs ... /jfb.14515
Abstract
A new species of the sand‐dwelling catfish genus Ammoglanis is described from marginal habitat of the lower Atabapo River, a left‐bank blackwater tributary of the upper Orinoco River in Amazonas, Venezuela, adjacent to the border with Colombia. is distinguished from all congeners by trunk pigmentation pattern consisting of scattered ventral chromatophores concentrated around the anal‐fin base and numerous additional meristic and anatomical characteristics. Ammoglanis natgeorum is the second species of Ammoglanis described from the Orinoco River basin after A. pulex, and several shared character states (e.g., 8 total dorsal‐fin rays, overall coloration pattern and presence of two finger‐like papillae posterior to chin) suggest that it is more closely related to A. obliquus (from the central Amazon basin) and A. pulex than to other congeners.
