Implicancias del conflicto Ameghino-Moreno sobre la colección de mamíferos fósiles realizada por Carlos Ameghino en su primera exploración al río Santa Cruz, Argentina

in september 1887, carlos ameghino, assistant preparator of paleontology at the museo de la plata, returned to the museum after a successful expedition to the banks of the santa cruz river. he had been commissioned by the director of this institution, francisco p. moreno, to carry out this fieldwork. by the end of that year, florentino ameghino, assistant director of the museum, unveiled the findings. he briefly described 122 taxa, 110 of which were new species. a few months later, florentino was dismissed from the museum and denied access to the collections. however, in 1889 ameghino expanded his descriptions of the material from 1887 and figured 74 of the 122 species previously described. in 1891, florentino said that the descriptions and figures he had published in 1889 were based on notes and sketches made before his dismissal. interestingly, many of the specimens depicted in his 1889 publication are in the ameghino collection at the museo argentino de ciencias naturales "bernardino rivadavia". larry marshall noticed the surprising location of these specimens, and in 1980, he concluded that florentino ameghino must have appropriated some specimens from the 1887 collection. the evidence presented here supports this conclusion and provides a framework for assessing the conformation of the type series for the species described in 1887. finally, it reveals the historical context for these events: competition among institutions and personal desires interacting to break what should have been an excellent scientific alliance.