| Palaeodictyoptera Temporal range: Late Carboniferous to Late Permian | |
|---|---|
 | |
| Reconstruction of Dunbaria fasciipennis | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Insecta |
| Superorder: | † Palaeodictyopteroidea |
| Order: | † Palaeodictyoptera Goldenberg, 1877 |
| Superfamily | |
The Palaeodictyoptera are an extinct order of medium-sized to very large, primitive Palaeozoic paleopterous insects. They are informative about the evolution of wings in insects.
They were characterized by beak-like mouthparts, used to pierce plant tissues for feeding. There is a similarity between their fore- and hindwings, and an additional pair of winglets on the prothorax, in front of the first pair of wings. They are known as "six-winged insects" because of the presence of a pair of wings on each of the thoracic segments. [1] [2] [3] [4] Their winglets provide clues to the origins of the first insect wings.
The mouthparts were elongated, and included sharp piercing stylets, and possibly a sucking pump-like organ. Unlike modern sucking insects, such as the Hemipterans, the mouthparts were held vertically below the head, or projected forwards. They probably used these organs to suck juices from plants, although some may have been ectoparasites, or predators. [5]
Some types attained huge size. For example, Mazothairos is estimated to have a wingspan of about 55 centimetres (22 in). Another distinctive feature was the presence of unusually long cerci, about twice the length of the abdomen. [5]
The Palaeodictyoptera are a paraphyletic assemblage of basal palaeodictyopteroidean insects, rather than a clade, because they gave rise to other insect orders. They range in time from the Middle Carboniferous (late Serpukhovian or early Bashkirian in age) to the late Permian.
Hymenoptera is a large order of insects, comprising the sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, in addition to over 2,000 extinct ones. Many of the species are parasitic. Females typically have a special ovipositor for inserting eggs into hosts or places that are otherwise inaccessible. This ovipositor is often modified into a stinger. The young develop through holometabolism —that is, they have a wormlike larval stage and an inactive pupal stage before they mature.
Halteres are a pair of small club-shaped organs on the body of two orders of flying insects that provide information about body rotations during flight. Insects of the large order Diptera (flies) have halteres which evolved from a pair of ancestral hindwings, while males of the much smaller order Strepsiptera (stylops) have halteres which evolved from a pair of ancestral forewings.
Butterflies are winged insects from the lepidopteran suborder Rhopalocera, characterized by large, often brightly coloured wings that often fold together when at rest, and a conspicuous, fluttering flight. The group comprises the superfamilies Hedyloidea and Papilionoidea. The oldest butterfly fossils have been dated to the Paleocene, about 56 million years ago, though they may have originated earlier.
Lepidoptera or lepidopterans is an order of winged insects that includes butterflies and moths. About 180,000 species of the Lepidoptera have been described, representing 10% of the total described species of living organisms, making it the second largest insect order with 126 families and 46 superfamilies. and one of the most widespread and widely recognizable insect orders in the world.
Odonata is an order of predatory flying insects that includes the dragonflies and damselflies. The two groups are distinguished with dragonflies usually being bulkier with large compound eyes together and wings spread up or out at rest, while damselflies are usually more slender with eyes placed apart and wings folded together along body at rest. Adult odonates can land, but rarely walk.
Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last common ancestor of those groups. The cladistic term for the same phenomenon is homoplasy. The recurrent evolution of flight is a classic example, as flying insects, birds, pterosaurs, and bats have independently evolved the useful capacity of flight. Functionally similar features that have arisen through convergent evolution are analogous, whereas homologous structures or traits have a common origin but can have dissimilar functions. Bird, bat, and pterosaur wings are analogous structures, but their forelimbs are homologous, sharing an ancestral state despite serving different functions.
In biology, homology is similarity due to shared ancestry between a pair of structures or genes in different taxa. A common example of homologous structures is the forelimbs of vertebrates, where the wings of bats and birds, the arms of primates, the front flippers of whales, and the forelegs of four-legged vertebrates like dogs and crocodiles are all derived from the same ancestral tetrapod structure. Evolutionary biology explains homologous structures adapted to different purposes as the result of descent with modification from a common ancestor. The term was first applied to biology in a non-evolutionary context by the anatomist Richard Owen in 1843. Homology was later explained by Charles Darwin's theory of evolution in 1859, but had been observed before this, from Aristotle onwards, and it was explicitly analysed by Pierre Belon in 1555.
Hemiptera is an order of insects, commonly called true bugs, comprising over 80,000 species within groups such as the cicadas, aphids, planthoppers, leafhoppers, assassin bugs, bed bugs, and shield bugs. They range in size from 1 mm (0.04 in) to around 15 cm (6 in), and share a common arrangement of piercing-sucking mouthparts. The name "true bugs" is often limited to the suborder Heteroptera.
Thrips are minute, slender insects with fringed wings and unique asymmetrical mouthparts. Entomologists have described approximately 7,700 species. They fly only weakly and their feathery wings are unsuitable for conventional flight; instead, thrips exploit an unusual mechanism, clap and fling, to create lift using an unsteady circulation pattern with transient vortices near the wings.
The insect order Neuroptera, or net-winged insects, includes the lacewings, mantidflies, antlions, and their relatives. The order consists of some 6,000 species. Neuroptera is grouped together with the Megaloptera and Raphidioptera (snakeflies) in the unranked taxon Neuropterida.
Megasecoptera is a Paleozoic insect order. There are 22 known families of megasecopterans, with about 35 known genera.
The most recent understanding of the evolution of insects is based on studies of the following branches of science: molecular biology, insect morphology, paleontology, insect taxonomy, evolution, embryology, bioinformatics and scientific computing. It is estimated that the class of insects originated on Earth about 480 million years ago, in the Ordovician, at about the same time terrestrial plants appeared. Insects are thought to have evolved from a group of crustaceans. The first insects were landbound, but about 400 million years ago in the Devonian period one lineage of insects evolved flight, the first animals to do so. The oldest insect fossil has been proposed to be Rhyniognatha hirsti, estimated to be 400 million years old, but the insect identity of the fossil has been contested. Global climate conditions changed several times during the history of Earth, and along with it the diversity of insects. The Pterygotes underwent a major radiation in the Carboniferous while the Endopterygota underwent another major radiation in the Permian.
Insects are hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body, three pairs of jointed legs, compound eyes, and a pair of antennae. Insects are the most diverse group of animals, with more than a million described species; they represent more than half of all animal species.
The external morphology of Lepidoptera is the physiological structure of the bodies of insects belonging to the order Lepidoptera, also known as butterflies and moths. Lepidoptera are distinguished from other orders by the presence of scales on the external parts of the body and appendages, especially the wings. Butterflies and moths vary in size from microlepidoptera only a few millimetres long, to a wingspan of many inches such as the Atlas moth. Comprising over 160,000 described species, the Lepidoptera possess variations of the basic body structure which has evolved to gain advantages in adaptation and distribution.
Insect morphology is the study and description of the physical form of insects. The terminology used to describe insects is similar to that used for other arthropods due to their shared evolutionary history. Three physical features separate insects from other arthropods: they have a body divided into three regions, three pairs of legs, and mouthparts located outside of the head capsule. This position of the mouthparts divides them from their closest relatives, the non-insect hexapods, which include Protura, Diplura, and Collembola.
Paraneoptera or Acercaria is a superorder of insects which includes lice, thrips, and hemipterans, the true bugs. It also includes the extinct order Permopsocida, known from fossils dating from the Early Permian to the mid-Cretaceous.
Insects are among the most diverse groups of animals on the planet, including more than a million described species and representing more than half of all known living organisms. The number of extant species is estimated at between six and ten million, found in nearly all environments, although only a small number of species occur in the oceans. This large extant means that the dietary habits of taxa include a large variety of behaviors.
The subphylum Hexapoda or hexapods comprises the largest clade of arthropods and includes most of the extant arthropod species. It includes the crown group class Insecta, as well as the much smaller class Entognatha, which includes three orders of wingless arthropods that were once considered insects: Collembola (springtails), Protura (coneheads) and Diplura. The insects and springtails are very abundant and are some of the most important pollinators, basal consumers, scavengers/detritivores and micropredators in terrestrial environments.
Kalligrammatidae, sometimes known as kalligrammatids or kalligrammatid lacewings, is a family of extinct insects in the order Neuroptera (lacewings) that contains twenty genera and a number of species. The family lived from the Middle Jurassic to the early Late Cretaceous before going extinct. Species of the family are known from Europe, Asia, and South America. The family has been occasionally described as "butterflies of the Jurassic" based on their resemblance to modern butterflies in morphology and ecological niche.
Mazothairos is an extinct genus of very large insect from the Carboniferous period. It was a member of the order Palaeodictyoptera. Although it is only known from very fragmentary remains from a single fossil, it is estimated to have had a wingspan of about 56 centimeters (22 in), making it one of the largest-known insects, only being rivaled in size by the largest members of the order Meganisoptera, such as Meganeura and Meganeuropsis.
| |||||||||||||||
| |||||||||||||||
| |||||||||||||||
