Derived, still living cockroach genus Cariblattoides (Blattida: Blattellidae) from the Eocene sediments of Green River in Colorado, USA

Abstract

Cariblattoides labandeirai sp.n. from the Eocene sediments of Green River in Colorado, USA bear only two plesiomorphies, but also several significant autapomorphies within the advanced and highly derived living cockroach genus. Thus, Cariblattoides with extant occurrence in the Caribbean and South America was historically common in the Nearctic, and represents important evidence for the occurrence of derived living genera of cockroaches ∼50 Ma ago. Generally, the vast majority of living genera were absent during the Palaeocene, thus the diversification of most living cockroach lineages near the Palaeocene/Eocene boundary must have been extremely rapid. Females of living C. suave, the type species, have identical (sophisticated) coloration of pronotum, but the most related living taxa are C. piraiensis and C. fontesi from Brazil (supported by phylogenetical analysis).

Latiblattella avita sp. nov. (Blattaria: Ectobiidae) from the Eocene Kishenehn Formation, Montana, USA

“…On the other hand, nearly all (9/11) cockroach genera from the Green River Formation and all genera from Dominican Republic and Mexican amber are extant. The marked differences in the composition of the Cenozoic and Cretaceous entomofauna suggest a very rapid evolution and radiation of the cockroach biota in the Paleocene and early Eocene (Vršanský et al, 2011;2012;2013;Gorochov, 2007). Interestingly, Namablatta, Diploptera, Ectobius, Allacta Saussure and Zehntner, 1895, Blattella and Supella are all extant genera that were present in the North and Central American Paleogene that are now, except for recent reintroduction, extinct in those areas (Vršanský et al, 2011).…”

“…Their absence, in combination with the highly advanced nature and restricted geographical distribution of the Dominican fauna (Central and South America), led Vršanský et al (2011) to suggest that an environmentally/biologically-mediated extinction event precipitated extinction of Paleogene fauna and set the stage for the evolution of a distinctly American fauna. On the other hand, Cariblattoides labandeira, present in the lacustrine sediments of the early Eocene Green River Formation, is an extant species with a present-day distribution in South America and the Caribbean (Vršanský et al, 2012). Latiblattella avita sp.n.…”

“…Extinct species number over 1,000 but nearly 80% of these are Paleozoic "roachoids" (Mitchell, 2013). The modern cockroach fauna is thought to have evolved immediately after the Cretaceous-Paleogene boundary (Vršanský et al, , 2011(Vršanský et al, , 2012 although only 53 fossil species have been described from the Cenozoic era (Mitchell, 2013;Arillo and Ortuño, GREENWALT & VIDLIČKA: NEW EOCENE COCKROACH 2 2005; Solórzano Kraemer, 2007;Gorochov, 2007). Undescribed material includes that presently studied from the Green River (e.g., the genera Blattella Caudell, 1903, Namablatta Rehn, 1937, Diploptera Saussure, 1864, Sigmella Hebard, 1940and Symploce Hebard, 1916 in Colorado (Vršanský et al, 2011(Vršanský et al, , 2012.…”

Afro-Asian cockroach from Chiapas amber and the lost Tertiary American entomofauna

“…Nevertheless, their position is obscure in some other analyses (see Ware et al 2008), and there is a single plesiomorphy recorded in respect to most Symploce Hebard, 1916 (M and CuA longitudinal), which is considered to be the most primitive blattellid in our previous studies (Vršanský 1997). Thus Supella is most likely derived from this genus (Vršanský et al 2011) or its predecessors.…”

“…Living cockroach species are still unknown in the fossil record, possibly because of rapid phylogeny at their species level (Vršan-ský 2008). Living genera of cockroaches (both primitive and advanced) are known since the Eocene (Vršanský et al 2011).…”