Being close relatives within the same genus, eight catfishes showed enough external differences, such as characteristic elongated mouths, hinting to their separate origin. Following a thorough morphological as well as molecular analysis, a team of researchers suggested that five previously known species along with three new ones, which they have found during their survey, need a new genus to accommodate for their specificity. The study, conducted by a Brazilian research team from Universidade Estadual Paulista and led by Dr. Fabio F. Roxo, is available in the open-access journal ZooKeys.
Among other physical peculiarities, the longer snout-like mouths of the herein discussed catfishes is a characteristic that sets them apart. This is also why the authors have chosen the name of Curculionichthys for the proposed genus, formed by the Latin word for "elongated snout" and the suffix "ichthys" meaning "fishes" in Greek.
Furthermore, one of the new species the researchers describe in the present paper surprises with its several dark-brown spots spread across its body. This colouration is unlike any other in its relatives that have various pigment patterns, yet never dark brown spots.
However, other overlapping morphological features as well as the closeness in the species' researched habitats suggest they have a common ancestor, once lived in the Amazonian drainages.
Roxo FF, Silva GSC, Ochoa LA, Oliveira C (2015) Description of a new genus and three new species of Otothyrinae (Siluriformes, Loricariidae). ZooKeys 534: 103-134. doi: 10.3897/zookeys.534.6169