A gill is a respiratory organ found in many aquatic organisms that extracts dissolved oxygen from water and excretes 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.
Crane fly is a common name referring to any member of the insect family Tipulidae, of the order Diptera, true flies in the superfamily Tipuloidea. Cylindrotominae, Limoniinae, and Pediciinae have been ranked as subfamilies of Tipulidae by most authors, though occasionally elevated to family rank. In the most recent classifications, only Pediciidae is now ranked as a separate family, due to considerations of paraphyly. In colloquial speech, crane flies are sometimes known as mosquito hawks or daddy longlegs, a term also used to describe opiliones or the family Pholcidae, both of which are arachnids. The larvae of crane flies are known commonly as leatherjackets.
The Sepsidae are a family of flies, commonly called the black scavenger flies or ensign flies. Over 300 species are described worldwide. They are usually found around dung or decaying plant and animal material. Many species resemble ants, having a "waist" and glossy black body. Many Sepsidae have a curious wing-waving habit made more apparent by dark patches at the wing end.
The Phoridae are a family of small, hump-backed flies resembling fruit flies. Phorid flies can often be identified by their escape habit of running rapidly across a surface rather than taking to the wing. This behaviour is a source of one of their alternate names, scuttle fly. Another vernacular name, coffin fly, refers to Conicera tibialis. About 4,000 species are known in 230 genera. The most well-known species is cosmopolitan Megaselia scalaris. At 0.4 mm in length, the world's smallest fly is the phorid Euryplatea nanaknihali.
Ephydridae is a family of insects in the order Diptera.
The Tephritidae are one of two fly families referred to as fruit flies, the other family being the Drosophilidae. The family Tephritidae does not include the biological model organisms of the genus Drosophila, which is often called the "common fruit fly". Nearly 5,000 described species of tephritid fruit fly are categorized in almost 500 genera of the Tephritidae. Description, recategorization, and genetic analyses are constantly changing the taxonomy of this family. To distinguish them from the Drosophilidae, the Tephritidae are sometimes called peacock flies, in reference to their elaborate and colorful markings. The name comes from the Greek τεφρος, tephros, meaning "ash grey". They are found in all the ecozones.
Thaumaleidae, the solitary midges or trickle midges, are a group of nematoceran flies related to the Ceratopogonidae, Chironomidae, and the Simuliidae. They are small, stocky, yellow to brown flies (3–4 mm). Very few species are known for this family. Larvae are found in films on rocks and the nonfeeding adults are usually found on foliage along the same streams in which the larvae are found. A few solitary midges are found in the Southern Hemisphere, but Thaumaleidae are generally an Holarctic family.
Gill slits are individual openings to gills, i.e., multiple gill arches, which lack a single outer cover. Such gills are characteristic of cartilaginous fish such as sharks, and rays, as well as primitive fish such as lampreys. In contrast, bony fishes have a single outer bony gill covering called an operculum. Most sharks can bite and pairs of gill slits, but a few species have 6 or 7 pairs. Shark gill slits lie in a row behind the head. The anterior edge of a gill slit is motile, moving outward to allow water to exit, but closing to prevent reverse flow. A modified slit, called a spiracle, lies just behind the eye, which assists the shark with taking in water during respiration and plays a major role in bottom–dwelling sharks. Spiracles are reduced or missing in active pelagic sharks. While the shark is moving, water passes through the mouth and over the gills in a process known as "ram ventilation". While at rest, most sharks pump water over their gills to ensure a constant supply of oxygenated water. A small number of species have lost the ability to pump water through their gills and must swim without rest. These species are obligate ram ventilators and would presumably asphyxiate if unable to move. Obligate ram ventilation is also true of some pelagic bony fish species.
Sphaeroceridae are a family of true flies in the order Diptera, often called small dung flies, lesser dung flies or lesser corpse flies due to their saprophagous habits. They belong to the typical fly suborder Brachycera as can be seen by their short antennae, and more precisely they are members of the section Schizophora. There are over 1,300 species and about 125 genera accepted as valid today, but new taxa are still being described.
The Fanniidae are a small group of true flies largely confined to the Holarctic and temperate Neotropical ecozones; there are 11 Afrotropical species, 29 Oriental, and 14 Australasian.
This glossary of entomology describes terms used in the formal study of insect species by entomologists.
The propodeum or propodium is the first abdominal segment in Apocrita Hymenoptera. It is fused with the thorax to form the mesosoma. It is a single large sclerite, not subdivided, and bears a pair of spiracles. It is strongly constricted posteriorly to form the articulation of the petiole, and gives apocritans their distinctive shape.
The Nematoceran family Axymyiidae is the sole member of the infraorder Axymyiomorpha, though it is often included within the infraorder Bibionomorpha in older classifications. It is known from only seven species in three genera, plus three fossil species.
Empididae is a family of flies with over 3,000 described species occurring worldwide in all the Ecozones but the majority are found in the Holarctic. They are mainly predatory flies like most of their relatives in the Empidoidea, and exhibit a wide range of forms but are generally small to medium-sized, non-metallic and rather bristly.
The Lonchaeidae are a family of acalyptrate flies commonly known as lance flies. About 500 described species are placed into 9 genera. These are generally small but robustly built flies with blue-black or metallic bodies. They are found, mainly in wooded areas, throughout the world with the exception of polar regions and New Zealand.
Platypezidae is a family of true flies of the superfamily Platypezoidea. The more than 250 species are found worldwide primarily in woodland habitats. A common name is flat-footed flies, but this is also used for the closely related Opetiidae which were included in the Platypezidae in former times.
Synthesiomyia nudiseta is one of the largest flies in the family Muscidae. The fly has a pair of forewings; the paired hind wings have been reduced to halteres that help with stability and movement during flight. Key characteristics of this species include plumose segmented aristae, well-developed calypters, and sternopleural bristles. Synthesiomyia nudiseta is a forensically important species because it is necrophilous and can therefore help determine the time of colonization for the post mortem interval with its known life cycle.
Lucilia coeruleiviridis, formerly Phaenecia coeruleiviridis, is commonly known as the green bottle fly, because of its metallic blue-green thorax and abdomen. L. coeruleiviridis was first discovered by French entomologist Justin Pierre Marie Macquart in 1855. It belongs to the Calliphoridae family and is one of many forensically important Diptera, as it is often found on decaying substances. L. coeruleiviridis is one of the most ubiquitous blow fly species in the southeastern United States, particularly in the spring and fall months.
The Diptera is a very large and diverse order of mostly small to medium-sized insects. They have prominent compound eyes on a mobile head, and one pair of functional, membraneous wings, which are attached to a complex mesothorax. The second pair of wings, on the metathorax, are reduced to halteres. The order's fundamental peculiarity is its remarkable specialization in terms of wing shape and the morpho-anatomical adaptation of the thorax – features which lend particular agility to its flying forms. The filiform, stylate or aristate antennae correlate with the Nematocera, Brachycera and Cyclorrhapha taxa respectively. It displays substantial morphological uniformity in lower taxa, especially at the level of genus or species. The configuration of integumental bristles is of fundamental importance in their taxonomy, as is wing venation. It displays a complete metamorphosis, or holometabolous development. The larvae are legless, and have head capsules with mandibulate mouthparts in the Nematocera. The larvae of "higher flies" (Brachycera) are however headless and wormlike, and display only three instars. Pupae are obtect in the Nematocera, or coarcate in Brachycera.
The family Nothybidae contains only the genus Nothybus, a group of colorful and elongated flies. The family has been recently revised.
Merz, B. & J.-P. Haenni. 2000. Morphology and terminology of adult Diptera (other than terminalia), pp. 21–51. In Contributions to a manual of Palaearctic Diptera, Vol. 1. (Eds L. Papp & B. Darvas.) (Science Herald, Budapest.) 978 pp.
