The story of research on Devonian echinoids from the Rhenish Massif: how historical circumstances created a mess

Research on sea urchins from the Rhenish Massif began in the 19^th and early 20^th century with description of several species from the Middle Devonian of the Eifel synclines. While some of the type specimens were stored in collections in Germany, others were eventually sold to the US. During World War II, several important specimens in the collections in Göttingen and Munich were destroyed, and with the German partition after the war, specimens stored in East Berlin became inaccessible to researchers from West Germany. Subsequently, when West German researchers J. Haffer and S. Jentsch attempted to revise the genus Lepidocentrus, they were limited by the lack of available material and synonymized the species L. lenneanus, whose type material had been lost, with L. muelleri, and assigned a newly found specimen from the Sauerland to L. rhenanus, whose holotype was unavailable to them. Current re-investigation by the authors shows that L. lenneanus and L. muelleri are distinct, and the assignment of the Sauerland specimen to L. rhenanus is a mistake that resulted in researchers overlooking that L. rhenanus and L. muelleri may be conspecific. Another species from the Sauerland was described by East German researcher H. Nestler in 1982 as Palaechinus praematurus and placed in the family Palaechinidae, which is confirmed by newly found material. This species is very significant, proving a pre-Carboniferous origin of the family, but surprisingly, Nestler’s work was never recognized or cited by later authors, presumably because it was simply unknown to other researchers.