The earliest discoveries of articulated fossil fishes (Actinopterygii) in the United States: A historical perspective

Abstract

The first articulated fossil fishes (Actinopterygii) unequivocally discovered in the United States were collected in the Early Jurassic lacustrine deposits of the Newark Supergroup. They were reported in 1816 by Benjamin Silliman (1779–1864), the founder of the American Journal of Science, in Parker Cleaveland (1780–1858)'s Elementary treatise on mineralogy and geology. These fossils were found in Westfield, near Middletown, Connecticut. Shortly thereafter, Edward Hitchcock (1793–1864) also reported the discovery of fossil fishes in Sunderland, Massachusetts. Up to now, these specimens seemed to be lost or impossible to pinpoint in American museums. Some of them also found their way to France. In October 1818 and August 1821, Silliman sent several of these fossil fish slabs to the French geologist Alexandre Brongniart (1770–1847). Searches in French institutional paleontological collections that hold scattered parts of Brongniart's collection made it possible to rediscover these historical fossils that went completely unnoticed so far. A specimen, identified as Redfieldius sp., from Westfield (Hartford Basin, Connecticut), is one of the very first authenticated fossil bony fishes ever reported in the United States. Eight slabs with “ichthyolites” (fossil fishes) collected in Sunderland (Deerfield Basin, Massachusetts) by Edward Hitchcock in or before April 1821 have also been rediscovered. Three of them contain type material (lectotype and paralectotype) of Semionotus fultus (Agassiz, 1833), the first scientifically named fossil fish from the Newark Supergroup. The other five slabs contain Semionotus sp. and Semionotus tenuiceps (Agassiz, 1835). This paper presents the historical context surrounding these early discoveries in the light of the correspondence between Hitchcock, Silliman and Brongniart. This study highlights an early example of transatlantic scientific exchange in geosciences at the beginning of the nineteenth century.