The Carboniferous is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period 358.9 Ma to the beginning of the Permian Period, 298.9 Ma. In North America, the Carboniferous is often treated as two separate geological periods, the earlier Mississippian and the later Pennsylvanian.
The Pennsylvanian is, on the ICS geologic timescale, the younger of two subperiods of the Carboniferous Period. It lasted from roughly 323.2 million years ago to 298.9 million years ago. As with most other geochronologic units, the rock beds that define the Pennsylvanian are well identified, but the exact date of the start and end are uncertain by a few hundred thousand years. The Pennsylvanian is named after the U.S. state of Pennsylvania, where the coal beds of this age are widespread.
A gill is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are kept moist. The microscopic structure of a gill presents a large surface area to the external environment. Branchia is the zoologists' name for gills.
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 and perch, but rarely walk.
A dragonfly is a flying insect belonging to the infraorder Anisoptera below the order Odonata. About 3,000 extant species of dragonflies are known. Most are tropical, with fewer species in temperate regions. Loss of wetland habitat threatens dragonfly populations around the world. Adult dragonflies are characterised by a pair of large, multifaceted, compound eyes, two pairs of strong, transparent wings, sometimes with coloured patches, and an elongated body. Many dragonflies have brilliant iridescent or metallic colours produced by structural coloration, making them conspicuous in flight. An adult dragonfly's compound eyes have nearly 24,000 ommatidia each.
Damselflies are flying insects of the suborder Zygoptera in the order Odonata. They are similar to dragonflies but are usually smaller and have slimmer bodies. Most species fold the wings along the body when at rest, unlike dragonflies which hold the wings flat and away from the body. Damselflies have existed since the Late Jurassic, and are found on every continent except Antarctica.
Aquatic insects or water insects live some portion of their life cycle in the water. They feed in the same ways as other insects. Some diving insects, such as predatory diving beetles, can hunt for food underwater where land-living insects cannot compete.
Meganeura is a genus of extinct insects from the Late Carboniferous. They resembled and are related to the present-day dragonflies and damselflies, and were predatory, with their diet mainly consisting of other insects. The genus belongs to the Meganeuridae, a family including other similarly giant dragonfly-like insects ranging from the Late Carboniferous to Middle Permian. With single wing length reaching 32 centimetres (13 in) and a wingspan about 65–75 cm (2.13–2.46 ft), M. monyi is one of the largest-known flying insect species.
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.
Insect wings are adult outgrowths of the insect exoskeleton that enable insects to fly. They are found on the second and third thoracic segments, and the two pairs are often referred to as the forewings and hindwings, respectively, though a few insects lack hindwings, even rudiments. The wings are strengthened by a number of longitudinal veins, which often have cross-connections that form closed "cells" in the membrane. The patterns resulting from the fusion and cross-connection of the wing veins are often diagnostic for different evolutionary lineages and can be used for identification to the family or even genus level in many orders of insects.
Namurotypus is an extinct genus of griffinfly with a single described species Namurotypus sippeli. It inhabited the large swamps of the Carboniferous period. Namaurotypus had a 15 cm long forewing and did not have secondary male sex organs as in modern dragonflies.
The Pseudostigmatidae are a family of tropical damselflies, known as helicopter damselflies, giant damselflies, or forest giants. The family includes the largest of all damselfly species. They specialize in preying on web-building spiders, and breed in phytotelmata, the small bodies of water held by plants such as bromeliads.
Before photosynthesis evolved, Earth's atmosphere had no free diatomic oxygen (O2). Small quantities of oxygen were released by geological and biological processes, but did not build up in the atmosphere due to reactions with reducing minerals.
The Carboniferous rainforest collapse (CRC) was a minor extinction event that occurred around 305 million years ago in the Carboniferous period. The event occurred at the end of the Moscovian and continued into the early Kasimovian stages of the Pennsylvanian.
An insect's respiratory system is the system with which it introduces respiratory gases to its interior and performs gas exchange.
The Stenophlebiidae is an extinct family of medium-sized to large fossil odonates from the Upper Jurassic and Cretaceous period that belongs to the damsel-dragonfly grade ("anisozygopteres") within the stem group of Anisoptera. They are characterized by their long and slender wings, and the transverse shape of the discoidal triangles in their wing venation.
The Tarsophlebiidae is an extinct family of medium-sized fossil odonates from the Upper Jurassic and Lower Cretaceous period of Eurasia. They are either the most basal member of the damsel-dragonfly grade ("anisozygopteres") within the stem group of Anisoptera, or the sister group of all Recent odonates. They are characterized by the basally open discoidal cell in both pairs of wings, very long legs, paddle-shaped male cerci, and a hypertrophied ovipositor in females.
Mazothairos is an extinct genus of very large insect that lived during 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 around 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.
Bojophlebia is an extinct genus of winged insect from the Pennsylvanian period of the Czech Republic. It includes only a single species, Bojophlebia prokopi, and is the only member of the family Bojophlebiidae. Bojophlebia prokopi was first described in 1985 by Jarmila Kukalová-Peck, who originally described it as a large mayfly-like insect. This original interpretation has since been rejected. Most recently, B. prokopi has been treated as a member of the infraclass Hydropalaeoptera, which also includes the Odonatoptera and Panephemeroptera. Bojophlebia is considered a sister group of all other members of the Hydropalaeoptera. A fossil that was described as a nymph of Bojophlebia is now considered to be a separate taxon, Carbotriplura kukalovae. The original description interpreted structures such as eyes and antennae, however these structures cannot be confirmed after restudy, although this may be an example of over-interpretation by Kukalová-Peck, as has happened with other extinct insects such as Carbotriplura and Gerarus.
Oligotypus is an extinct genus of griffinfly in the family Paralogidae. This genus is known from 4 species from the Carboniferous to Permian.
