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The Cretaceous reveals a rich fossil record of insects throughout both hemispheres, and the mid-Cretaceous Burmese amber contains the most diverse biota in this period and has a unique preservation state. We describe a new blattulid cockroach Vrtula exploratoremvalidator sp. n., which differs from other congeners in the dark colouration pattern on pronotum and smaller size. The species was apparently not extremely rare in and outside northern Myanmar amber as several unpublished specimens do exist. The dark forewing colouration might appear cryptic. Stratigraphically, the genus was restricted to the Barremian-Cenomanian and palaeogeographically it further emphasises taxonomical similarities of Burmite and Laurasia. Aside from Burmite, it was reported in sediments of Shin-Khuduk, Upper Wealden, Bon Tsagaan, Baissa, and possibly Montsec with V. tsaganica comb. n., V. sama Vršanský 2008 and several undescribed species. A list of cockroaches from burmite is provided.

Living cockroach genera were tracked from Kimmeridgian and after K/Pg they vastly dominate. All Eocene genera Cariblattoides Allacta Blattella Ectobius and Diploptera (in Green River; observed also on Cenozoic Allacta Supella Neoblattella and Latiblattella) are advanced and homoplastically retained a single symplesiomorphy – a divided subgenital plate, which later reduced in multiple parallelisms of living ectobiids. Balta Tepper, 1893; Blattella Caudell, 1903 sp. 1, Ectobius amberscapeus sp. n., and particularly brachypterous female of Temnopteryx electrokosmi sp. n. (Ectobiidae) from Kaliningrad amber evidences origin of the advanced Eurasian genera around PETM and also rarely insights into a brachypterous cohort absent in sedimentary record. It contrasts with the early-derived Miocene Supella Latiblattella Anaplecta and the only later derived Gutierrezina and Cariblatta in ambers of Americas (Chiapas and Dominica). Baltic Stegoblatta Euthyrrhapha Balta germari (Shelford, 1910) comb. n; Blatta Blattella Periplaneta Ischnoptera Ceratinoptera Phyllodromica (Pro)Holocompsa Homopteroidea Paraeuthyrrhapha and Namablatta additionally represent 29 species with diverse palaeogeography – and suggest subtropical (not temperate warm) climate. Numerous sibling species additionally validate sibling-species occurrence patterns observed in other ambers and sediments. Big size of Baltic (and Ukraine) cockroaches suggests high viscosity of the source resin.

This paper focuses on optimizing the propulsion system, specifically the control aspect. It presents the design of a sensorless inverter with field-oriented control for BLDC motors, primarily intended for copters. The theoretical part covers motor modeling and the design of the control structure, employing field-oriented control and a sensorless approach using back-electromotive force observer to estimate the rotor position. The physical implementation of the control system is based on an electronic inverter with two logical components. The control component utilizes a microprocessor for FOC control and incorporates memory, sensor systems, and peripherals. The power component ensures controlled energy transfer through complementary signals and feedback measurement. Communication between components and with the higher-level system, regarding control and configuration, is also addressed. Finally, the inverter underwent testing on a measurement platform and during copter flights. The measurements focused on motor speed estimation and control performance under load and no-load conditions. The assessment concludes with trust scaling and temperature measurements of the inverter.

A unique assemblage of arthropods (n = 32), ferns, horsetails and a ginkgo discovered in Algerian Brezina differs from all known (and rather uniform) Laurasian and Gondwanan Cretaceous biotas, suggesting a large isolated landmass at the microcontinent known as Adria-Turkey, Serbia-Turkey or “Greater Adria”. The mineral assemblage is characteristic for siliciclastic sediments which underwent deep post-depositional burial and reached late diagenetic conditions of alteration. The ?Hauterivian assemblage of aquatic and terrestrial insects was dominated by cockroaches and beetles. Mantodean, tettigarctid cicad, aquatic ephemeropterans, dragonflies, spinicaudatan, and an arachnomorph spider also occur. Freshwater insects relate to Eurasian ones such as the beetle Timarchopsis cyrenaicus (Ponomarenko, 1977) and mayfly Hexameropsis africana Sinitshenkova, 1975 or belong to cosmopolitan biota as a dragonfly pre-imaginal stage (Aeschnoidea, ?Gomphaeschnidae). The continental biota differed. Cockroaches except Elisama Giebel, 1856, praying mantis and possibly also dragonfly genera were mostly indigenous and distant from the known morphotypes. The extinct family Mesoblattinidae (represented by Otazka systematicka gen. et sp. n., Meloblatta brezinica gen. et sp. n.) and the still-extant Corydiidae (Afrophaga extincta gen. et sp. n.) dominated. The Mesozoic families Blattulidae (? Elisama algeriaensis sp. n.) and Liberiblattinidae (Kriedoblatta gondwanensis gen. et sp. n. and ? Kurablattina samsonovi sp. n. restricted record in Early Jurassic of Australia), and Holocompsinae (Sajda equatorialis gen. et sp. n.) restricted to Spain during Cretaceous and also represented by extant forms were also present. The dominant Laurasian Caloblattinidae and Gondwanan (and burmite) Alienopteridae were not preserved or absent.

Currently, there are only four formally described species of cockroaches from the Oligocene. Here, we describe a new member of this cohort, Latiblattella basaltica sp. n. from the late Oligocene Enspel Fossillagerstätte. This colored cockroach is a member of the extant Ectobiidae (Pseudophyllodromiinae) and lacks any observable plesiomorphies with members of this family. Neotropical species of the genus Latiblattella Hebard, 1917 share characters with species within the genera Neoblattella Shelford, 1911 and Macrophyllodromia Saussure et Zehntner, 1893 with a contemporary Nearctic/Neotropical distribution (which is similar to Nyctibora Burmeister, 1838 known from the spatiotemporaly related locality of Rott in Germany). Two partly articulated specimens, in addition to two isolated forewings, indicate only short or no pre-depositional transport. The dominance of the species in the Enspel assemblage (n = 4/4, active fully winged males) indicates a low cockroach diversity within the crater lake basin or specific taphonomic conditions unfavorable for the preservation of cockroaches. The latter is indicated by the contrasting extraordinary abundance of bibionids, winged sexuals of ants, and curculionid beetles within the association.

Unequivocal palaeontological evidence for viruses is usually absent. A specimen of the extinct predatory cockroach Stavba babkaeva gen. et sp. n. from Cretaceous Myanmar amber (98 Ma) shows symptoms of Deformed Wing Virus infection caused by pathogenic DWV-Iflavirus. The hindwing is undeveloped and both curled forewings are symmetrically deformed, differing from environmentally caused asymmetries known from Pripyat and Fukushima. While some unknown cockroach mutation might have the same symptoms, ontogenetic defects (such as incomplete moulting) differ in complete lack of sclerotization, modified forewing bases and presence on both wings. Post-depositional, taphonomic influence can be excluded due to local character of the deformation (forewings on both sides) while other areas are undeformed. Drying shrinking can be excluded due to brittle character of the wing, which would crack instead – and it could not, be local either. Pathogenic RNA-viruses probably circulated among vertebrates and invertebrate decomposers/predators in the dinosaur-age ecosystems. Our discovery complements an indirect putative evidence of Retrovirus infection that modified dinosaur bones.

A new genus of Middle Jurassic cockroach belonging to the family Liberiblattinidae viz., Entropiagen. nov., with a new species E. initialissp. nov., is described from the Bathonian sediments of the Daohugou in Inner Mongolia, China. This species has multiply deformed wings supporting the rapid evolution of this group during the Middle Jurassic. Voucher specimen is deposited with the Capital Normal University in Beijing.

Cockroaches, with an evolutionary history going back 350 Myr and with over 100,000 fossil specimens collected so far, form one of the most consistent fossil records in terrestrial arthropods. In addition to their descendants, the eusocial termites and predatory mantises, their variability is presented by such diverse forms as bioluminescent, somatically translucent, beetlelike, predatory, aquatic, semisocial, eusocial and viviparous species. In spite of their conservativeness at higher taxonomic levels, the evolutionary tempo of cockroach species is comparatively high. The modern families of cockroaches only appear as early as the Cretaceous, and the oldest taxon closely resembling a living genus described here from the Early Cenomanian ca. 96 Ma French amber greatly increases, by 46 Myr, their expected antiquity. ?Blattella lengleti sp. n. – a close relative of a common synanthropic German cockroach, indicates that this genus andor its very close relative shared environments with dinosaurs, almost 100 Myr before it occupied human households. © 2008 WILEYVCH Verlag GmbH & Co. KGaA, Weinheim

Vitisma occidentalissp. nov. from the Lower Cretaceous of Spain, closely related to V. rasnitsynifrom the Lower Cretaceous of Siberia, is described based on isolated forewings. An isolated hindwing is tentatively attributed to the same species. Besides representatives of the Blattulidae and Mesoblattinidae, two similar species of Polyphagidae, one archaic (Vitisma occidentalis), the other more advanced (Cretaholocompsa montsecana), are found in the Lower Barremian of Spain (Montsec). The new subfamily Vitisminae comprises Vitismaand Cretaholocompsaand some undescribed species from the Lower Cretaceous of Mongolia and the Turonian of Kazakhstan. The vitisminae probably shared a cryptic niche in, and fed on the fruiting organs of unknown plants and/or in their fallen remains.