The dustywings, Coniopterygidae, are a family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 of Pterygota

Pterygota

Pterygota is a subclass of insects that includes the winged insects. It also includes insect orders that are secondarily wingless ....

 (winged insects) of the net-winged insect order

Order (biology)

In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...

 (Neuroptera

Neuroptera

The insect order Neuroptera, or net-winged insects, includes the lacewings, mantidflies, antlions, and their relatives. The order contains some 6,010 species...

). About 460 living species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 are known. These tiny insects can usually be determined to genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 with a hand lens according to their wing venation, but to distinguish species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

, examination of the genitals by microscope

Microscope

A microscope is an instrument used to see objects that are too small for the naked eye. The science of investigating small objects using such an instrument is called microscopy...

 is usually necessary.

Description and ecology

In general habitus

Morphology (biology)

In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....

, the adults are quite unlike other net-winged insects. With their small size - wingspan is between 1.8 and 5 millimetres - and their translucent brownish wings usually covered with the namesake whitish dust of wax

Wax

thumb|right|[[Cetyl palmitate]], a typical wax ester.Wax refers to a class of chemical compounds that are plastic near ambient temperatures. Characteristically, they melt above 45 °C to give a low viscosity liquid. Waxes are insoluble in water but soluble in organic, nonpolar solvents...

y scales, they are at the first glance more similar to whiteflies (Aleyrodidae) which are true bugs and thus among the Pterygota not at all closely related to net-winged insects. A distinguishing feature is that like many other Neuroptera, dustywings carry their wings nearly side-by-side when at rest, whereas whiteflies carry them almost flat across the back. There are no more than two veins across the costa

Costa

Costa may refer to:* Costa , including origin of the name and people sharing the surname* Costa, scientific term, from Latin costa "rib" ** In botany, the central strand of a bryophyte leaf or thallus...

l field and few cross-veins in general - unique among the living net-winged insects, dustywings do not actually have the "net-winged" venation. Some Coniopterygidae, like the genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 Conwentzia, have only vestigial hindwings; others, like Helicoconis females, are completely wingless.

Dustywings are strongly associated with woody plant

Plant

Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...

s, on and around which they usually spend their entire lives. Females depost their eggs singly on bark

Bark

Bark is the outermost layers of stems and roots of woody plants. Plants with bark include trees, woody vines and shrubs. Bark refers to all the tissues outside of the vascular cambium and is a nontechnical term. It overlays the wood and consists of the inner bark and the outer bark. The inner...

 or leaves

Leaves

-History:Vocalist Arnar Gudjonsson was formerly the guitarist with Mower, and he was joined by Hallur Hallsson , Arnar Ólafsson , Bjarni Grímsson , and Andri Ásgrímsson . Late in 2001 they played with Emiliana Torrini and drew early praise from the New York Times...

. Dustywing larva

Larva

A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...

e are around 3.5 mm long. Their mouthpart

Insect mouthparts

Insects exhibit a range of mouthparts, adapted to particular modes of feeding. The earliest insects had chewing mouthparts...

s consist of short, straight sucking tubes covered by the labrum (upper "lip"). They are crepuscular

Crepuscular

Crepuscular animals are those that are active primarily during twilight, that is during dawn and dusk. The word is derived from the Latin word crepusculum, meaning "twilight." Crepuscular is, thus, in contrast with diurnal and nocturnal behavior. Crepuscular animals may also be active on a bright...

 and dwell on shrub

Shrub

A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...

s and tree

Tree

A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...

s, where they feed on small invertebrate

Invertebrate

An invertebrate is an animal without a backbone. The group includes 97% of all animal species – all animals except those in the chordate subphylum Vertebrata .Invertebrates form a paraphyletic group...

s like scale insect

Scale insect

The scale insects are small insects of the order Hemiptera, generally classified as the superfamily Coccoidea. There are about 8,000 species of scale insects.-Ecology:...

s, aphid

Aphid

Aphids, also known as plant lice and in Britain and the Commonwealth as greenflies, blackflies or whiteflies, are small sap sucking insects, and members of the superfamily Aphidoidea. Aphids are among the most destructive insect pests on cultivated plants in temperate regions...

s and mite

Mite

Mites, along with ticks, are small arthropods belonging to the subclass Acari and the class Arachnida. The scientific discipline devoted to the study of ticks and mites is called acarology.-Diversity and systematics:...

s, as well as on arthropod

Arthropod

An arthropod is an invertebrate animal having an exoskeleton , a segmented body, and jointed appendages. Arthropods are members of the phylum Arthropoda , and include the insects, arachnids, crustaceans, and others...

 eggs; the mouth tubes are used for sucking fluids from the prey. There are usually two generation

Generation

Generation , also known as procreation in biological sciences, is the act of producing offspring....

s each year.

Systematics and taxonomy

Due to the dustywings' many apomorphies, the superfamily

Taxonomic rank

In biological classification, rank is the level in a taxonomic hierarchy. Examples of taxonomic ranks are species, genus, family, and class. Each rank subsumes under it a number of less general categories...

 Coniopterygoidea was formerly believed to be monotypic

Monotypic

In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...

, and the primitive traits of their larvae were held to evidence a quite basal place among the net-winged insects. But in fact the spongillaflies (Sisyridae

Sisyridae

The Sisyridae, commonly known as spongeflies or spongillaflies, is a family of winged insects of the order Neuroptera. Approximately 60 living species are known.-Description:...

), formerly allied with the Osmylidae

Osmylidae

Osmylidae are a small family of winged insects of the net-winged insect order Neuroptera. The osmylids are found all over the world except in North America. A common species through most of Europe is Osmylus fulvicephalus.-Description and ecology:...

 in error due to their larvae's convergent

Convergent evolution

Convergent evolution describes the acquisition of the same biological trait in unrelated lineages.The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, both birds and bats do, and are capable of powered flight. The wings are...

 morphology

Morphology (biology)

In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....

, seem to be close relatives of the Coniopterygidae, more plesiomorphic altogether as adults but with a number of peculiar and highly divergent apomorphies, particularly in the larvae. So even though the spongillaflies are not generally placed in the Coniopterygoidea as of yet, they most likely form a clade

Clade

A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

 with the dustywings and thus it would seem that the Coniopterygoidea, rather than being maintained as an unnecessarily monotypic

Monotypic

In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...

 taxon

Taxon

|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...

, are better expanded to signify that the spongillaflies and the dustywings are each other's closest relatives among the net-winged insects. This is all the more significant because in this apparent clade, there would be a highly interesting and exactly opposing pattern of evolution

Evolution

Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...

 - primitive larvae and highly advanced adults in the dustywings, versus primitive adults and very advanced larvae in the spongillaflies.

Numerous fossil

Fossil

Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

 taxa are known from the Late Jurassic

Late Jurassic

The Late Jurassic is the third epoch of the Jurassic Period, and it spans the geologic time from 161.2 ± 4.0 to 145.5 ± 4.0 million years ago , which is preserved in Upper Jurassic strata. In European lithostratigraphy, the name "Malm" indicates rocks of Late Jurassic age...

 onwards. Most of these, as well as a number of living genera, are of basal or uncertain position in dustywing phylogeny:

• Alboconis (fossil)
• Apoglaesoconis (fossil)
• Archiconiocompsa (fossil)
• Archiconis (fossil)
• Conwentzia
• Gallosemidalis (fossil)
• Glaesoconis (fossil)
• Heminiphetia (fossil)
• Hemisemidalis (fossil)
• Juraconiopteryx (fossil)
• Libanoconis (fossil)
• Libanoseminalis (fossil)
• Pararchiconis (fossil)
• Phthanoconis (fossil)
• Semidalis
• Spiloconis

The supposed Early Jurassic

Early Jurassic

The Early Jurassic epoch is the earliest of three epochs of the Jurassic period...

 dustywing genus Archiconiopteryx actually seems to be a whitefly-like true bug.