Roach nectarivory, gymnosperm and earliest flower pollination evidence from Cretaceous ambers

A new species of the vitismin cockroach genus Perspicuus Koubová, 2020 from the Late Cretaceous (Santonian) of Hungary

Mesozoic amber cockroaches are rare compared to sedimentary imprints and are only known from Myanmar, Lebanon, France, Russia and USA. Perspicuus csincsii sp. n. from the Late Cretaceous (Santonian) ajkaite amber of Hungary with very long cerci, cup-like terminal palpomere of the maxillary palp and fully carinated legs, is clearly distinguished from all other Vitisminae species by the unique, black forewing with small light-coloured dots/stripes and the absence of pubescence on the wings (autapomorphies). The second cockroach described from the ajkaite adds important data to the distribution pattern of Vitisminae during the Late Cretaceous and further highlights the similarity of the ajkaite and burmite biotas.

A New Subgenus of the Genus Phenolia (Coleoptera, Nitidulidae) from Myanmar Cretaceous Amber with Taxonomic, Phylogenetic and Bionomic Notes on the 'Nitidulid' Group of Families

A new subgenus, Palaeoronia subgen. nov., is described from the Cretaceous amber of North Myanmar (Kachin State) and assigned to the genus Phenolia. The type species of the new subgenus, Phenolia (Palaeoronia) haoranae subgen. et sp. nov., is characterized by a rather 'archaic' aspect. A discussion of the diagnostic and structure of the Soronia-complex of genera (together with the Phenolia-complex of genera) (Nitidulinae, Nitidulini) is proposed. Reasons for the 'conservatism' of this group during the Mesozoic and Cenozoic are discussed. The position of the Apophisandridae stat. nov. (type genus Apophisandra) and the transfers of the following genera into this family: Cretaretes, Electrumeretes, Furcalabratum, Pelretes, Polliniretes, Protokateretes, Protonitidula, and Scaporetes, from the Kateretidae, Nitidulidae or Cerambycidae are grounded. The relations of the family Parandrexidae (with inclusion of the genus Cretoparacucujus, transferred from Boganiidae with a proposal of the subfamily Cretoparacucujinae subfam.nov.), Martynoposis and Parandrexis are considered. The genus Antirhelus gen. nov. (type species Heterhelus buzina) is assigned to the new subfamily, Antirhelinae subfam. nov. in the family Kateretidae. The fossil records of the 'nitidulid' group of families (Apophisandridae stat. nov., Kateretidae, Nitidulidae, Parandrexidae, Smicripidae and possibly Boganiidae) are reviewed. The relationship of the family Boganiidae, some aspects of pollination and pollinophagy, and also changes in beetle diet in the past are discussed. The lectotype of Parandrixis parvula is designated.

Alienopterix santonicus sp. n., a metallic cockroach from the Late Cretaceous ajkaite amber (Bakony Mts, western Hungary) documents Alienopteridae within the Mesozoic Laurasia

Cockroaches (Blattaria s. str.) were documented from numerous amber localities around the world, representing both extinct and extant families. Alienopteridae is an extinct cockroach family known only from the Cretaceous of Gondwana (Brazil, Botswana, Myanmar amber) and the Cenozoic of North America. Alienopterix santonicus sp. n. from the Late Cretaceous amber of the Ajka Coal Formation (Bakony Mts, western Hungary) extends the rich geographical distribution of the family into Laurasia during the Mesozoic. As a member of the presumably pollinator cohort Alienopteridae, this species could have played an important role in the Ajka Coal ecosystem during the Santonian. The microrectangular structures of the forewing suggest that the new species likely possessed a metallic colouration already known from the group. Combined with the disruptive body pattern this could have served as an advanced camouflage. The microrectangular structures of the forewing were compared to integument microstructures of extant insects with metallic colouration. Various arthropod taxa are already known from ajkaite, and the new discovery further emphasizes the importance of this amber.

Predators or Herbivores: Cockroaches of Manipulatoridae Revisited with a New Genus from Cretaceous Myanmar Amber (Dictyoptera: Blattaria: Corydioidea)

Manipulator modificaputis Vršanský and Bechly, 2015 (Manipulatoridae, Corydioidea) is a purported predatory cockroach from Cretaceous Myanmar amber, based on a single male. It is distinctive by the nimble head, elongate pronotum and legs, and particularly by the extraordinarily long maxillary palpi. In the present study, we redescribe Manipulator modificaputis based on six new fossils including males and females, and comment on the original description. The closely related Manipulatoides obscura gen. & sp. nov. is proposed on the basis of five fossils, including males and females. It differs from Manipulator in weaker spination of the legs, including the type-C forefemoral spination instead of the type-A of Manipulator. Some undetermined adults and nymphs are also described. We discuss the ethology of Manipulatoridae and speculate that they might feed on flowers. They are unlikely to be specialized predators since they lack necessary weaponry for capturing prey; in contrast, their unique morphotype appears to be suitable for efficient foraging and locomotion amid flowering twigs. The possibility of being kleptoparasites of the spider-web is also discussed. In addition, regenerated four-segmented tarsi are found from the new species.

Reconstructing the ecology of a Cretaceous cockroach: destructive and high-resolution imaging of its micro sensory organs

Animals highly depend on their sensory organs to detect information about their surrounding environment. Among animal sensory organs, those of insects have a notable ability to detect information despite their small size, which might be, therefore, one of the reasons for the evolutionary success of insects. However, insect sensory organs are seldom fossilized in sediments due to their small size and fragility. A potential solution for this problem is the study of exceptionally well-preserved fossil material from amber. Unfortunately, the resolution of existing non-destructive analysis is insufficient to observe details of these micro sensory organs even with amber preservation. Here, we focus on the analysis of the micro sensory organs of an extinct male cockroach (Huablattula hui Qiu et al., 2019) in Cretaceous amber by combining destructive and non-destructive methods. Compared to extant species inhabiting dark environments, H. hui has relatively large compound eyes, and all the antennal sensilla for detecting multimodal information observed here are fewer or smaller. The characteristics of these sensory organs support the diurnality of the bright habitats of H. hui in contrast to many extant cockroaches. Like extant male mantises, grooved basiconic type sensilla exist abundantly on the antenna of the fossilized specimen. The abundance of grooved basiconic sensilla in mantid males results from using sex pheromones, and therefore, H. hui may have likewise used mantis-like intersexual communication. These lines of evidence suggest that the ecology and behavior of Cretaceous cockroaches were more diverse than those of related extant species.

A new cockroach (Blattodea, Corydiidae) with pectinate antennae from mid-Cretaceous Burmese amber

A new species of fossil cockroach, Fragosublattapectinata gen. et sp. nov., is described from mid-Cretaceous Burmese amber. The new species is assigned to the family Corydiidae based on the following combination of characters: pronotum with tubercles, tegmina obovate with smallish anal region and spinules on the antero-ventral margin of the front femur (type C1). The new species is the second reported cockroach with ramified antennae. This finding broadens the diversity of Blattodea in mid-Cretaceous Burmese amber and provides further evidence of convergent evolution for antennal structures among different insect lineages.

Generalist Pollen-Feeding Beetles during the Mid-Cretaceous

The Cretaceous fossil record of amber provides a variety of evidence that is essential for greater understanding of early pollination strategies. Here, we describe four pieces of ca. 99-million-year-old (early Cenomanian) Myanmar amber from Kachin containing four closely related genera of short-winged flower beetles (Coleoptera: Kateretidae) associated with abundant pollen grains identified as three distinct palynomorphotypes of the gymnosperm Cycadopites and Praenymphaeapollenites cenomaniensis gen. and sp. nov., a form-taxon of pollen from a basal angiosperm lineage of water lilies (Nymphaeales: Nymphaeaceae). We demonstrate how a gymnosperm to angiosperm plant-host shift occurred during the mid-Cretaceous, from a generalist pollen-feeding family of beetles, which served as a driving mechanism for the subsequent success of flowering plants.