Edmund A. Jarzembowski

Insect origination and extinction in the Phanerozoic

Abstract Insects (Superclass Hexapoda) are the most successful group of living terrestrial arthropods and the richness of their fossil record is only just beginning to be realized with the recent publication of two extensive databases. Hexapods first appeared in the Early Devonian, post-dating the Cambrian ‘explosion’ of marine arthropods by some 140 Ma. The earliest Hexapoda belong to primitively wingless taxa; however, these ‘Apterygota’ comprise less than 1% of all hexapod species. The appearance of winged insects (Pterygota) in the mid-Carboniferous was accompanied by a major adaptive radiation of non-holometabolous hexapods at ordinal level This was supplemented in the Permian by the radiation of insects with complete metamorphosis (Holometabola). The number of insect orders present in this period was similar to that at the present day. The family data suggest four major periods of origination in the Phanerozoic, with peaks in the Permo-Carboniferous, Early Jurassic, Early Cretaceous and Eocene. Unlike the Tertiary, the Palaeozoic and Cretaceous peaks are accompanied by considerable turnover of families; they are followed by reduced palaeodiversity in the Early Triassic and Late Cretaceous and Palaeocene. The former decline may be linked with the general extinction at the Permian/Triassic boundary and the latter with the rise of the angiospermous flowering plants. Insect generic data for the Phanerozoic reflect the pattern shown by families but not orders. In general, insect diversity may be explained by an overall trend towards low extinction and steady origination at a subordinal level since the Palaeozoic.

Phylogeny and classification of the Stenophlebioptera (Odonata: Epiproctophora)

Abstract The Juraheterophlebiidae, new family of the “heterophlebioid” lineage, the Henrotayiidae, new family of the “anisopteroid” lineage, the Prostenophlebiidae and the Liassostenophlebiidae, new families of the Stenophlebioptera, and three new genera and species of the Stenophlebiidae are described from the Mesozoic of Germany, Spain, England, Kazakhstan, and Mongolia. The phylogenetic positions of the families Erichschmidiidae and Gondvanogomphidae are discussed. A tentative phylogenetic analysis of the Anisopteromorpha is proposed. This significantly extends our knowledge on the palaeogeographical distribution of the Stenophlebioptera and the Epiproctophora (“dragondamselflies”).

Taphonomy of the insects from the Insect Bed (Bembridge Marls), late Eocene, Isle of Wight, England

The environmental setting and taphonomy of the insect fauna of the Insect Bed, Bembridge Marls (late Eocene; 36 Ma) of the Isle of Wight is described. Cluster analysis of taxonomic data on the insect fauna of a diversity of modern tropical environments, together with that of the Bembridge Marls, shows that the insects of the latter are characteristic of a primary sub-tropical/tropical forest subject to significant seasonal rainfall. A similar approach indicates that the sample of taxa preserved in the Insect Bed is biased toward insects from leaf litter and lower herbage microhabitats. External ornamentation of the cuticle is preserved on a micron scale, and the individual microfibrils of the procuticle can be distinguished. The insects of the Bembridge Marls are remarkable in preserving cuticle and mineralized internal tissues in a largely uncompacted state. Chemical analysis (py-GC/MS) reveals that the cuticle is composed of an aliphatic polymer, possibly due to polymerization of cuticular waxes during diagenesis. No chitin was detected. The soft tissues, which include sarcolemma and muscle fibres, are preserved through replacement in calcite.

New insects from the Weald Clay of the Weald

The following new insect taxa are described and their significance discussed: Yuripopovia woottoni gen. et sp. nov. (Hemiptera: Progonocimicidae); Architipula austeni sp. nov. and Gynoplistial mitchelli sp. nov. (Diptera: Tipulidae); Necrotaulius mantellorum sp. nov. (Trichoptera: Necrotauliidae); Archisphex boothi sp. nov. and Angarosphex goldringi sp. nov. (Hymenoptera: Sphecidae). Valditermes brenanae (Isoptera: Hodotermitidae) is redescribed and its relationships and palaeoecology are discussed. Hebeitermes from the Lower Cretaceous of China is considered to be a blattodean.

Fossil Cockroaches or Pinnule Insects

Willi Hennigs case for rejecting fossil insects with external ovipositors from the order Blattodea (Cockroaches) is discussed, as well as the leaf-mimicry hypothesis involving Cockroaches and ferns which was first suggested by Samuel Scudder nearly 100 years ago. Both proposals are rejected, as is the use of the name ‘Pinnule Insects’ for Palaeozoic Cockroaches.

New damselflies (Odonata: Zygoptera: Hemiphlebiidae, Dysagrionidae) from mid-Cretaceous Burmese amber

Zheng, D., Zhang, Q., Nel, A., Jarzembowski, E.A., Zhou, Z., Chang, S.-C. & Wang, B., May 2016. New damselflies (Odonata: Zygoptera: Hemiphlebiidae, Dysagrionidae) from mid-Cretaceous Burmese amber. Alcheringa XX, xxx–xxx. ISSN 0311-5518 Two damselflies, Burmahemiphlebia zhangi gen. et sp. nov. and Palaeodysagrion cretacicus gen. et sp. nov., are described from the mid-Cretaceous Burmese amber. Burmahemiphlebia zhangi is the first record of Hemiphlebiidae from this amber, although the family was cosmopolitan during the Mesozoic. It can be readily distinguished from all other members of Hemiphlebiidae in having very short MP and CuA veins, and in its rectangular discoidal cell. The new fossils support the view that hemiphlebiid damselflies were one of the dominant groups of Zygoptera during the Mesozoic. Palaeodysagrion cretacicus is the first dysagrionid damselfly from Burmese amber and the second Mesozoic representative of this predominantly Paleogene group. It differs from other members of Dysagrionidae in having a unique elongate discoidal cell. These new finds increase the diversity of damselflies in mid-Cretaceous Burmese amber. Daran Zheng* [dranzheng@gmail.com], Su-Chin Chang [suchin@hku.hk], Department of Earth Sciences, The University of Hong Kong, Hong Kong Special Administrative Region, PR China; Qingqing Zhang [qqzhang@nigpas.ac.cn], Edmund A. Jarzembowski† [edj@nigpas.ac.cn], Bo Wang‡ [bowang@nigpas.ac.cn], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing 210008, PR China; André Nel [anel@mnhn.fr], Institut de Systématique, Évolution, Biodiversité, ISYEB-UMR 7205-CNRS, MNHN, UPMC, EPHE, Muséum national d’Histoire naturelle, Sorbonne Universités, 57 rue Cuvier, CP 50, Entomologie, F-75005, Paris, France; Zhicheng Zhou [172692308@qq.com], The PLA Information Engineering University, 62 Kexue Ave, Gaoxin District, Zhengzhou 450002, Henan, PR China. *Also affiliated with State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing 210008, PR China. †Also affiliated with Department of Earth Sciences, The Natural History Museum, London SW7 5BD, UK. ‡Also affiliated with Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China.

Curious snipe-flies (Diptera: Rhagionidae) from the Purbeck of Dorset, the Wealden of the Weald and the Lower Cretaceous of Spain and Transbaikalia

Four new Lower Cretaceous species of the rhagionid genus Ptiolinites are described: Ptiolinites heidiae sp. nov. and P. raypearcei sp. nov. from southern England, P almuthae sp. nov. from Spain and P. oudatchinae sp. nov. from northern Transbaikalia. Re-evaluation of the antennal structure allows us to assign Ptiolinites to the subfamily Rhagioninae.

A century plus of fossil insects

Progress in palaeoentomology is reviewed since Goss (1878–80) with special reference to the British fauna and including the geological histories of the major insect and hexapod groups and of social insects. Other types of information provided by insect remains including environment, adaptation and stratigraphy are briefly discussed. A selected bibliography is provided (including all references to fossil insects in the Proceedings ) and some hopes expressed for future work. Two lepidopteran leaf mines are named, Stigmellites? gossi and S.? centennis spp. nov. and a new insect ichnotaxon, Foliofossor cranei ichnogen. et sp. nov. is described.

The occurrence and diversity of Coal Measure insects

Insects are generally considered to be rare in the Upper Carboniferous Coal Measures. However, recent work in the Westphalian D of SW England suggests that many have been overlooked in the past. This is because wings, which are the most characteristic insect fossils, may be mistaken for detached ‘fern’ pinnules, which are much more common. The resemblance may be functional convergence rather than leaf-mimicry. The earliest members of the class Insecta in the strict sense occur in the Upper Carboniferous. Eleven major divisions or orders are represented in the Coal Measures of which only four are still living. Primitively wingless insects (Archaeognatha) are present, relatives of familiar living insects such as the silverfish. There are numerous winged insects, some of which could fold their wings (Neoptera) and others which could not (Palaeoptera). Palaeopterous insects were more diverse than today. They include three extinct orders (Palaeodictyoptera, Megasecoptera, Diaphanopterodea) which were probably plant suckers like present clay bugs. Other extinct palaeopterous insects (order Protodonata) were probably aerial predators like modern dragonflies, and included some of the largest insects of all time (‘giant dragonflies’). By far the most common neopterous insects were cockroaches (Blattodea) which outnumber all other insects in the Upper Carboniferous. This abundance is perhaps less surprising when one considers the general picture of the coal forests as warm, humid, and rich in organic matter. Another important neopterous group was the extinct order Protorthoptera, which is probably related only in part to extant Orthoptera (grasshoppers, crickets and locusts). There is no evidence at this time of higher insects such as flies, fleas, beetles, moths and butterflies, ants, bees and wasps.

Extreme adaptations for probable visual courtship behaviour in a Cretaceous dancing damselfly

Courtship behaviours, frequent among modern insects, have left extremely rare fossil traces. None are known previously for fossil odonatans. Fossil traces of such behaviours are better known among the vertebrates, e.g. the hypertelic antlers of the Pleistocene giant deer Megaloceros giganteus. Here we describe spectacular extremely expanded, pod-like tibiae in males of a platycnemidid damselfly from mid-Cretaceous Burmese amber. Such structures in modern damselflies, help to fend off other suitors as well as attract mating females, increasing the chances of successful mating. Modern Platycnemidinae and Chlorocyphidae convergently acquired similar but less developed structures. The new findings provide suggestive evidence of damselfly courtship behaviour as far back as the mid-Cretaceous. These data show an unexpected morphological disparity in dancing damselfly leg structure, and shed new light on mechanisms of sexual selection involving intra- and intersex reproductive competition during the Cretaceous.