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Marsh fly (Sciomyzidae)
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Diptera
(unranked): Cyclorrhapha
Section: Schizophora


The Schizophora are a section of true flies containing 78 families, which are collectively referred to as muscoids, although technically the term "muscoid" should be limited to flies in the superfamily Muscoidea; this is an example of informal, historical usage persisting in the vernacular. The section is divided into two subsections, the Acalyptratae and Calyptratae, which are commonly referred to as acalyptrate muscoids and calyptrate muscoids, respectively.

The defining feature of the Schizophora is the presence of a special structure used to help the emerging adult fly break free of the puparium; this structure is an inflatable membranous sac called the ptilinum that protrudes from the face, above the antennae. The inflation of the ptilinum (using fluid hemolymph rather than air) creates pressure along the line of weakness in the puparium, which then bursts open along the seam to allow the adult to escape. When the adult emerges, the fluid is withdrawn, the ptilinum collapses, and the membrane retracts entirely back inside the head. The large, inverted, "U"-shaped suture in the face through which it came, however, is still quite visible, and the name "Schizophora" ("split-bearers") is derived from this ptilinal or frontal suture. The term was first used by Eduard Becher.

In contrast to eggs of other arthropods, most insect eggs are drought-resistant, because inside the maternal chorion, two additional membranes develop from embryonic tissue, the amnion and the serosa. This serosa secretes a cuticle rich in chitin that protects the embryo against desiccation. In the Schizophora, however, the serosa does not develop, but these flies lay their eggs in damp places, such as rotting organic matter. [1]

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Fly Order of insects

Flies are insects of the order Diptera, the name being derived from the Greek δι- di- "two", and πτερόν pteron "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced mechanosensory organs known as halteres, which act as high-speed sensors of rotational movement and allow dipterans to perform advanced aerobatics. Diptera is a large order containing an estimated 1,000,000 species including horse-flies, crane flies, hoverflies and others, although only about 125,000 species have been described.

Whitefly Family of insects

Whiteflies are Hemipterans that typically feed on the undersides of plant leaves. They comprise the family Aleyrodidae, the only family in the superfamily Aleyrodoidea. More than 1550 species have been described.

Pupa Life stage of some insects undergoing transformation

A pupa is the life stage of some insects undergoing transformation between immature and mature stages. The pupal stage is found only in holometabolous insects, those that undergo a complete metamorphosis, with four life stages: egg, larva, pupa, and imago. The processes of entering and completing the pupal stage are controlled by the insect's hormones, especially juvenile hormone, prothoracicotropic hormone, and ecdysone. The act of becoming a pupa is called pupation, and the act of emerging from the pupal case is called eclosion or emergence.

Tachinidae Family of insects

The Tachinidae are a large and variable family of true flies within the insect order Diptera, with more than 8,200 known species and many more to be discovered. Over 1300 species have been described in North America alone. Insects in this family commonly are called tachinid flies or simply tachinids. As far as is known, they all are protelean parasitoids, or occasionally parasites, of arthropods, usually other insects. The family is known from many habitats in all zoogeographical regions and is especially diverse in South America.

Aschiza Group of insects

The Aschiza are a section of the Brachycera. Two large families, the Syrphidae and the Phoridae, and a number of smaller taxa are in this group. They are similar to most of the familiar Muscomorpha with one notable exception; they do not possess a ptilinum, so lack the prominent ptilinal suture on the face as in other muscoid flies. They do still have a puparium with a circular emergence opening, but it is not as precisely ellipsoid in shape as is typical for other muscoids. The term was first used by Eduard Becher.

Apple maggot Species of fly

The apple maggot, also known as the railroad worm, is a species of fruit fly, and a pest of several types of fruits, mainly apples. This species evolved about 150 years ago through a sympatric shift from the native host hawthorn to the domesticated apple species Malus domestica in the northeastern United States. This fly is believed to have been accidentally spread to the western United States from the endemic eastern United States region through contaminated apples at multiple points throughout the 20th century. The apple maggot uses Batesian mimicry as a method of defense, with coloration resembling that of the forelegs and pedipalps of a jumping spider.

Serous membrane

In anatomy, serous membrane is a smooth tissue membrane of mesothelium lining the contents and inside wall of body cavities, which secrete serous fluid to allow lubricated sliding movements between opposing surfaces. The serous membrane that covers internal organs is called a visceral membrane; while the one that covers the cavity wall is called the parietal membrane. Between the two opposing serosal surfaces is often a potential space, mostly empty except for the small amount of serous fluid.

Phoridae Family of flies

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.

Braulidae Family of flies

Braulidae, or bee louse, is a family of fly (Diptera) with seven species in two genera, Braula and Megabraula. Found in honey bee colonies, these most unusual wingless and small flies, are not a true bee parasite, and are barely recognizable as Diptera, as they have the superficial appearance of mites or lice.

Platypezoidea Superfamily of flies

The Platypezoidea are a superfamily of true flies of the section Aschiza. Their closest living relatives are the Syrphoidea, which, for example, contain the hoverflies. Like these, the adults do not burst open their pupal cases with a ptilinum when hatching, thus the Aschiza do not have the inverted-U-shaped suture above the antennae. They are, however, muscomorphs, thus have a particular type of pupal case resembling a rounded barrel and called puparium.

Glossary of entomology terms List of definitions of terms and concepts commonly used in the study of entomology

This glossary of entomology describes terms used in the formal study of insect species by entomologists.

Muscomorpha Order of flies

The Brachyceran infraorder Muscomorpha is a large and diverse group of flies, containing the bulk of the Brachycera, and, most of the known flies. It includes a number of the most familiar flies, such as the housefly, the fruit fly, and the blow fly. The antennae are short, usually three-segmented, with a dorsal arista. Their bodies are often highly setose, and the pattern of setae is often taxonomically important.


The ptilinum is an eversible pouch on the head, above the base of the antenna in schizophoran flies. It is used to force off the end of the puparium in order for the fly to emerge, and after this inflation at emergence, the ptilinum collapses back inside the head, marked thereafter only by the ptilinal suture or frontal suture.

<i>Nasonia</i> Genus of wasps

Nasonia are a genus of small pteromalid parasitoid wasps that sting and lay eggs in the pupae of various flies. The fly species that Nasonia usually parasitize are primarily blow flies and flesh flies, making Nasonia a useful tool for biocontrol of these pest flies. The small match-head sized wasps are also referred to as jewel wasps based on the emerald sheen of their exoskeleton.

Desiccation tolerance refers to the ability of an organism to withstand or endure extreme dryness, or drought-like conditions. Plants and animals living in arid or periodically arid environments such as temporary streams or ponds may face the challenge of desiccation, therefore physiological or behavioral adaptations to withstand these periods are necessary to ensure survival. In particular, insects occupy a wide range of ecologically diverse niches and, so, exhibit a variety of strategies to avoid desiccation.

Insect Class of invertebrates

Insects or Insecta are pancrustacean hexapod invertebrates and the largest group within the arthropod phylum. Definitions and circumscriptions vary; usually, insects comprise a class within the Arthropoda. As used here, the term Insecta is synonymous with Ectognatha. Insects have a chitinous exoskeleton, a three-part body, three pairs of jointed legs, compound eyes and one pair of antennae. Insects are the most diverse group of animals; they include more than a million described species and represent more than half of all known living organisms. The total number of extant species is estimated at between six and ten million; potentially over 90% of the animal life forms on Earth are insects. Insects may be found in nearly all environments, although only a small number of species reside in the oceans, which are dominated by another arthropod group, crustaceans, which recent research has indicated insects are nested within.

Insect morphology

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, have three pairs of legs, and mouthparts located outside of the head capsule. It is this position of the mouthparts which divides them from their closest relatives, the non-insect hexapods, which includes Protura, Diplura, and Collembola.

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.

<i>Physocephala tibialis</i> Species of fly

Physocephala tibialis is a species of thick-headed fly found throughout the eastern United States, often near flowering plants. The adult fly is primarily black with a yellow face and thin white stripes on the abdomen. It is commonly found along the east coast of the United States and is often found near flowering plants.

Glossina fuscipes is a riverine fly species in the genus Glossina, which are commonly known as tsetse flies. Typically found in sub-Saharan Africa, G. fuscipes is a regional vector of African trypanosomiasis, commonly known as sleeping sickness, that causes significant rates of morbidity and mortality among humans and livestock. Consequently, the species is among several being targeted by researchers for population control as a method for controlling the disease.


  1. Jacobs, C.G.; Rezende, G.L.; Lamers, G.E.; van der Zee, M. (2013). "The extraembryonic serosa protects the insect egg against desiccation". Proceedings of the Royal Society of London B: Biological Sciences. 280 (1764): 20131082. doi:10.1098/rspb.2013.1082. PMC   3712428 . PMID   23782888.