A new species of spongiphorine earwig in Miocene amber from the Dominican Republic (Dermaptera: Spongiphoridae)

Abstract

Earwigs (Dermaptera) are an often-ignored group of polyneopteran insects, with nearly 2000 extant species distributed throughout the world (Grimaldi & Engel, 2005; Stork, 2018). All of the modern diversity belongs to the suborder Neodermaptera, a clade that first definitively appears in the Early Cretaceous (Engel et al., 2011; Wolfe et al., 2016), but likely diverged in the Late Jurassic, although there is a rich gradation of earlier earwig variety extending back to at least the Late Triassic (Kelly et al., 2017). The earlier-diverging lineages (such as Archidermaptera, Eodermaptera, and Turanodermaptera [Turanodermatidae]) lack some of the otherwise characteristic synapomorphies of crown-group Dermaptera, such as loss of ocelli, loss of tegminal venation, or reduction of the ovipositor (Grimaldi & Engel, 2005). While there is a rich variety of forms and morphological disparity among fossil Dermaptera, their record compared to other orders remains comparatively meagre. Given this overall scarcity in the fossil record, there is nonetheless a decent variety of lineages documented from various Cenozoic deposits (Wappler et al., 2005). A fairly large number of taxa have been described from Palaeogene and early Neogene impressions (e.g., Heer, 1865; Zhang, 1989; Zhang et al., 1994; Chatzimanolis & Engel, 2010), although the precise systematic placement of many are challenging to confirm given the nature of their preservation and the characters widely needed to properly assign earwigs. Those species preserved as amber inclusions offer a wider breadth of characters from which to ascertain affinities, and earwigs have been previously described from Oise, Baltic, Dominican, and Mexican ambers (Burr, 1911a; Nel et al., 2003; Ross & Engel, 2013; Engel, 2016, 2017).