new synonymy:
Scleronema minutum (Boulenger 1891)
is a senior synonym of
Pygidium angustirostris Devincenzi, 1942

published in:
Ferrer, J. & L.R. Malabarba (2020):
Systematic revision of the Neotropical catfish genus Scleronema (Siluriformes: Trichomycteridae), with descriptions of six new species from Pampa grasslands.
Neotropical Ichthyology 18 (2): e190081

distribution (from publication):
Scleronema minutum occurs in the laguna dos Patos system, lower rio Uruguay basin and lower rio Paraná basin. In the former, the species is widely distributed in rivers and streams that drain directly to laguna dos Patos (Brazil) and lagoa Mirim (Brazil and Uruguay). The species is known from only one stream of the right bank of the lower rio Uruguay, the arroyo Yuquerí Chico (Argentina), and widespread in following drainages of its other side: rio Negro (Brazil and Uruguay), rio Ibicuí (Brazil), río Dayman (Uruguay), río Queguay (Uruguay), and río San Salvador (Uruguay). In the lower rio Paraná basin, the species has few records to two tributaries of its left bank, the arroyo Feliciano and río Guayquiraro, Argentina.