<p><strong>Santonian cockroaches from Yantardakh amber (Russia: Taimyr) differ in dominance</strong></p>

Abstract

Cretaceous amber cockroaches are known only from Lebanon, Myanmar and France. An assemblage of 14 dictyopterans (2 unidentified) from Santonian amber of Yantardakh, Taimyr, Russia is reported here, comprising only 0.3 % of ˃5,000 collected insects. Small pieces (0.03–0.30 g) contain six immature individuals of Liberiblattinidae, one predatory Ocelloblattula or its close relative, one Perlucipecta immature (Mesoblattinidae), one represents typical Blattulidae and Chaeteessites minutissimus along with two primitive true mantodeans. The assemblage lacks any modern taxon, common in other Upper Cretaceous sedimentary rocks and ambers, while diverse parasitic Evaniidae indirectly confirms the presence of them. A biome with a diversity of otherwise rare Liberiblattinidae (emended diagnosis revealed herein) with high evolutionary potential expressed in giving rise to numerous other families was thus present. Differences observed were probably caused by another source tree as evidenced by the different chemistry of Taimyr amber compared to other ambers.