Late Cretaceous ophiuroids in the Binkhorst Collection at the Museum für Naturkunde, Berlin, reassessed

A small lot of latest Cretaceous brittlestars from the Maastrichtian type area, contained in the Binkhorst [van den Binkhorst] Collection at the Museum für Naturkunde in Berlin, is restudied and, in part, illustrated for the first time. Presumably, these thirteen specimens represent only a portion of the ophiuroid material referred to in two papers by Binkhorst van den Binkhorst, both published in 1859, because all are assignable to two species which are common only in the Nekum and Meerssen members of the type Maastrichtian, namely Felderophiura vanderhami Jagt, 1991, and Ophiomusium lux Jagt & Kutscher in Jagt, 2000. Brittlestar material from lower levels within the Maastricht Formation (i.e., Valkenburg, Gronsveld, Schiepersberg and Emael members) referred to by Binkhorst has not been traced. Alternatively, Binkhorst’s original records could have been based on specimens contained in collections of his contemporaries, such as Joseph de Bosquet and Casimir Ubaghs. In most, if not all, of such cases, representatives of Ophiomusium gr. granulosum (Roemer, 1841) [sensu Jagt, 2000] are involved. Based on our own observations in the Maastricht area, Binkhorst’s specimens of F. vanderhami and O. lux must have originated from the upper Meerssen Member where these two species are locally common. In fact, mostly isolated discs are preserved in the present lot, with only some retaining proximal arm portions, which suggests these were picked from sieving residues after bulk sample processing. More or less complete specimens of both species have also been collected recently, but these are confined to bedding planes. Although preservation is mediocre, diagnostic features of both F. vanderhami and O. lux are readily apparent.