Jarmila Kukalová-Peck

Origin and evolution of insect wings and their relation to metamorphosis, as documented by the fossil record

In contemporary entomology the morphological characters of insects are not always treated according to their phylogenetic rank. Fossil evidence often gives clues for different interpretations. All primitive Paleozoic pterygote nymphs are now known to have had articulated, freely movable wings reinforced by tubular veins. This suggests that the wings of early Pterygota were engaged in flapping movements, that the immobilized, fixed, veinless wing pads of Recent nymphs have resulted from a later adaptation affecting only juveniles, and that the paranotal theory of wing origin is not valid. The wings of Paleozoic nymphs were curved backwards in Paleoptera and were flexed backwards at will in Neoptera, in both to reduce resistance during forward movement. Therefore, the fixed oblique‐backwards position of wing pads in all modern nymphs is secondary and is not homologous in Paleoptera and Neoptera. Primitive Paleozoic nymphs had articulated and movable prothoracic wings which became in some modern insects transformed into prothoracic lobes and shields. The nine pairs of abdominal gillplates of Paleozoic mayfly nymphs have a venation pattern, position, and development comparable to that in thoracic wings, to which they are serially homologous. Vestigial equivalents of wings and legs were present in the abdomen of all primitive Paleoptera and primitive Neoptera. The ontogenetic development of Paleozoic nymphs was confluent, with many nymphal and subimaginal instars, and the metamorphic instar was missing. The metamorphic instar originated by the merging together of several instars of old nymphs; it occurred in most orders only after the Paleozoic, separately and in parallel in all modern major lineages (at least twice in Paleoptera, in Ephemeroptera and Odonata; separately in hemipteroid, blattoid, orthopteroid, and plecopteroid lineages of exopterygote Neoptera; and once only in Endopterygota). Endopterygota evolved from ametabolous, not from hemimetabolous, exopterygote Neoptera.

Flight adaptations in Palaeozoic Palaeoptera (Insecta)

The use of available morphological characters in the interpretation of the flight of insects known only as fossils is reviewed, and the principles are then applied to elucidating the flight performance and techniques of Palaeozoic palaeopterous insects. Wing‐loadings and pterothorax mass total mass ratios are estimated and aspect ratios and shape‐descriptors are derived for a selection of species, and the functional significance of wing characters discussed. Carboniferous and Permian ephemeropteroids (‘mayflies’) show major differences from modern forms in morphology and presumed flight ability, whereas Palaeozoic odonatoids (‘dragonflies’) show early adaptation to aerial predation on a wide size‐range of prey, closely paralleling modern dragonflies and damselflies in shape and wing design but lacking some performance‐related structural refinements. The extensive adaptive radiation in form and flight technique in the haustellate orders Palaeodictyoptera, Megasecoptera, Diaphanopterodea and Permothemistida is examined and discussed in the context of Palaeozoic ecology.

Phylogeny of Higher Taxa in Insecta: Finding Synapomorphies in the Extant Fauna and Separating Them from Homoplasies

Most currently applied systematic methods use post-groundplan character states to reconstruct phylogenies in modern higher Insecta/Arthropoda taxa. But, this approach is unable to separate synapomorphies from frequently occurring homoplasies. Conflicting, unresolved and unrealistic higher-level phylogenies result. The reasons are analyzed. A contrasting “groundplan” method, long used in Vertebrata and found to be superior in resolving higher-level phylogenies, is described. This method, as used for insects, uses a highly diversified morphological organ system (such as limb/wing), identifies its homologues in all subphyla and classes, records the full history of its character transformation series in all lineages from the shared Paleozoic ancestor to modern times, pursues the full homologization of its character states in all modern orders, and verifies these data with evidence from other fields of biology. Only such an extremely broad dataset provides the complex information needed to identify and homologize the groundplan character states in modern orders and other higher taxa in the insect/arthropod fauna. After this is accomplished, the gate to recognizing higher-level synapomorphies is open. Only groundplan-level character states include distinct synapomorphies, since homoplasies are either absent or easily detectable. Examples are given. The interpretations of higher phylogenies and evolutionary processes in Hexapoda, based on the unpredictable and often misleading post-groundplan character states found in extant, Tertiary and Mesozoic fauna, are critically compared with those based on the evolution of organ systems, by using the groundplan method.

Zoraptera wing structures: evidence for new genera and relationship with the blattoid orders (Insecta: Blattoneoptera)

Abstract. The order Zoraptera has traditionally been thought to contain only one family (Zorotypidae) and one genus (Zorotypus Silvestri). An analysis of known zorapteran wings shows that the wing venation contains character sets indicative of the existence of seven genera: Zorotypus, Brazilozoros gen.n., Centrozoros gen.n., Floridazoros gen.n., Latinozoros gen.n., Meridozoros gen.n. and Usazoros gen.n. The wing venation of Meridozoros leleupi (Weidner) from the Galapagos Islands, Ecuador and Venezuela is described here for the first time.

Glaresidae, archaeopteryx of the Scarabaeoidea (Coleoptera)

Abstract. Evidence is presented that Glaresidae are the most primitive livinj scarabaeoid group and as such represent the sister group of the rest of the Scarabaeoidea. This is based on a review of the states of seventy‐two morphologica characters. The plesiomorphic states of many characters are unique to the Glaresidae or are shared with other primitive scarabaeoids; seven may be synapomorphic with other groups and two are autapomorphic for the family.

Adult and Immature Calvertiellidae (Insecta: Palaeodictyoptera) from the Upper Palaeozoic of New Mexico and Czechoslovakia

It is generally agreed that insects have been abundant since the Upper Paleozoic. However, occurrences of fossil insects in the Upper Carboniferous and Permian are quite rare, mainly because of the scarcity of deposition sites. Especially rare are localities that yield a diverse and well preserved assemblage sampling a large community. This is regrettable since the insects, through their enormous dispersal potential and rapid evolution, are well suited for paleobiogeographical studies, especially for comparisons on an intercontinental level. It is assumed that Paleozoic plants and insects coevolved through a close and mutual association, and that this interaction, on all levels of development, was of fundamental importance in directing evolutionary trends. Hence researches on fossil insects and plants complement each other and hold great potential for paleogeography, paleoclimatology and stratigraphy of the Upper Paleozoic, as well as for theoretical evolutionary studies in both groups. On the entire North American continent there are at present only two localities which have yielded a rich and diverse fossil insect fauna comparable to the best Paleozoic localities of Europe and Asia: Mazon Creek, Illinois (Middle Pennsylvanian deposits equal to Westphalian C-D of the European divisions), and Elmo, Kansas (Lower Permian deposits). Concerning potentially promising regions, the Upper Paleozoic strata of New Mexico have attracted the attention of specialists in the last decade through random discoveries of fossil insects (8 specimens from the Manzanita Mountains, SE of Albuquerque, and one specimen from Santa Fe Creek, Santa Fe). Those fossils suitable for description were treated by Carpenter (1970). Since the North American West is important in spanning the gap in paleobiogeographical knowledge of the

Homologisation of the anterior articular plate in the wing base of Ephemeroptera and Odonatoptera

In the search for the sister group of modern Ephemerida, we used the evolutionary groundplan method to identify synapomorphies in wing articulation. The evolutionary approach is necessary because post-groundplan wing adaptations have obscured the phylogenetically informative higher-level synapomorphies in modern Ephemerida, Odonata and Neoptera. Protowing-level sclerites are recognisable fragments of the first limb-derived pleuron, arranged in eight rows above the pathways delivering blood to the eight principal wing veins. Each row includes three sclerites (proxalare, axalare and fulcalare) which articulate with the basivenale (wing blood sinus). Over the course of the pterygote evolutionary history, many row-sclerites have assembled into clusters, plates, or processes, the composition of which can be most clearly recognised by comparison with ancestral Paleozoic fossils. The extant orders Ephemerida and Odonata (Palaeoptera: Hydropalaeoptera) share a derived anterior articular plate (AAP) composed of four fused sclerites (two axalaria and two fulcalaria) belonging to the precostal and costal rows. This plate represents a complex and unique synapomorphy. In Neoptera, precostal and costal fulcalaria are fused to basivenalia to form a humeral plate, and axalaria are obscured by the tegula. Palaeoptera include two subdivisions, extant Hydropalaeoptera and extinct Palaeodictyopteroida.

A substitute name for the extinct genus Stenelytron Kukalová (Protelytroptera)

In 19661 described a new species ofthe extinct order Protelytroptera belonging to a new genus, Stenelytron, and representing a new family, Stenelytridae. Having recently learned from Professor F. M. Carpenter that the name Stenelytron is preoccupied, I am herein proposing a replacement name, as follows: Labidelytron, nomen novumpro Stenelytron Kukalov, 1966, p. 102, non Handlirsch, 1906, p. 451. The type species, Stenelytron enervatum Kukalovh, 1966, original designation, becomes Labidelytron enervatum (Kukalovh), new combination. The genus is known only from the Permian of New South Wales, Australia. The family name, Stenelytridae Kukalov, 1966, p. 102, is herein replaced by Labidelytridae. The genus Xenelytron (Kukalovi), 1966, p. 105, also from the Permian ofNew South Wales, is the only other genus known in the family.