Blattella Fossil Cockroach Beetle Insect Prehistoric Cretaceous Collection

The so-called cockroaches are insects of the order of the Blattodea to whose superorder Dyctioptera also belong the mantises (Mantodea).
Cockroaches are an ancient group: the first cockroach-like fossils date back to the Carboniferous period, about 320 million years ago, as well as their fossil nymphs. However, those ancestral species lacked the internal ovipositories of modern cockroaches. These insects have remained unchanged over time, without special adaptations suitable for sucking such as aphids, diptera, hymenoptera or other more specialized insects; they have chewing systems and are probably among the most primitive of living neoptera insects. They are common and resistant insects and can tolerate a wide range of environments, from arctic cold to tropical heat. Tropical cockroaches are often much larger than temperate species and, contrary to popular belief, extinct species, such as Archimylacris (Carboniferous) and Apthoroblattina (Permian), were not larger than modern species.
Until the 19th century, scientists believed that cockroaches were an ancient group of insects originating in the Devonian, but the species that lived in that period differ from modern cockroaches in that they had long external ovipositors and were the common ancestors of mantises and cockroaches. Since the body, hind wings and parts of the mouth are not easily preserved in fossils, kinship relationships remain controversial. The first fossils of modern cockroaches with internal ovipositors appeared at the beginning of the Cretaceous period. A recent phylogenetic analysis suggests that cockroaches originated at least in the Jurassic period.

A 2016 comprehensive review of 981 specimens of fossil cockroaches from the Lower Cretaceous laminated limestones of the Crato Formation of Northeast Brazil shows that they belong to eleven taxa, including Piniblattella limai, P. magna sp. n., Perlucipecta santanensis. sp. n., Raptoblatta waddingtonae; Ocelloblattula santanensis sp. n., Elisama brevis (= E. Americana, syn.n.), E. hindwingnii sp. n., Ponopterix axelrodi (= P. maxima syn.n.), Umenopterix burkhardi comb. n., and Cratovitisma oldreadi (Umenocoleidae = Cratovitismidae syn.n. = Ponopterixidae syn.n.). The family Ectobiidae is numerically most abundant in the assemblage of cockroaches of the Crato Formation (83 % of cockroaches), followed by Blattulidae (13 %) and Umenocoleidae (4 %). 79.2% of specimens are complete and fully articulated. Members of the family Alienopteridae are probably also present. Representatives of a relatively common Mesozoic superfamily Caloblattinoidea are missing. With the exception of the endemic genera Cratovitisma and Raptoblatta and the exclusively Gondwanan genus Ocelloblattula, all other genera were cosmopolitan. Taxonomic richness of cockroaches of the Crato Formation is thus rather low, and consists of geologically long-ranging and geographically-widespread genera, genera restricted to Gondwana, and short-ranging endemic genera found in the Crato Formation only.