Ptiliidae is a

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

of very tiny

beetle Beetles are insects that form the order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 describ ...

s with a cosmopolitan distribution. This family contains the smallest of all beetles, with a length when fully grown of . The weight is approximately 0.4 milligrams. They are colloquially called featherwing beetles, because the hindwings are narrow and feathery. Ptillid wings are feathery due to the much higher effective viscosity of air at small body sizes, which makes normal insect wings much less efficient. Unlike other small insects with feathery wings, such as parasitic wasps like fairyflies, ptillids do not fly using a clap and fling motion, but instead fly using a figure of eight pattern where the wings clap at the apex of the upward and downward strokes. They are capable of flying at speeds comparable to their larger relatives. The small size has forced many species to sacrifice some of their anatomy, like the heart, crop, and gizzard. While the exoskeleton and respiration system of the insects seems to be the major limiting factors regarding how large they can get, the limit for how small they can become appears to be related to the space required for their nervous and reproductive systems. Adults and larvae are microphagous, feeding on the spores and hyphae of fungi, as well as other organic detritus. They are found in a wide variety of habitats, including rotting and fungus infested wood, tree holes, under kelp along shorelines and within or near ant and termite nests. The

eggs Humans and human ancestors have scavenged and eaten animal eggs for millions of years. Humans in Southeast Asia had domesticated chickens and harvested their eggs for food by 1,500 BCE. The most widely consumed eggs are those of fowl, especial ...

are very large in comparison to the adult female (maybe half the length) so only one egg at a time can be developed and laid.

Parthenogenesis Parthenogenesis (; from the Greek grc, παρθένος, translit=parthénos, lit=virgin, label=none + grc, γένεσις, translit=génesis, lit=creation, label=none) is a natural form of asexual reproduction in which growth and developmen ...

is exhibited by several species. Reitter-1908 table65

There are approximately 600 described

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

in 80 genera, but large numbers of specimens in collections await description and the true number of species is likely to be much higher than this. Fossil ptiliids have been recorded from the Oligocene, roughly 30

million years ago The abbreviation Myr, "million years", is a unit of a quantity of (i.e. ) years, or 31.556926 teraseconds. Usage Myr (million years) is in common use in fields such as Earth science and cosmology. Myr is also used with Mya (million years ago) ...

from the

Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...

, 46.2–43.5 million years ago, and from the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...

Lebanese and

Burmese amber Burmese amber, also known as Burmite or Kachin amber, is amber from the Hukawng Valley in northern Myanmar. The amber is dated to around 100 million years ago, during the latest Albian to earliest Cenomanian ages of the mid-Cretaceous period. The ...

, dated to 125 and 99 million years ago, respectively. The family is divided into 3 subfamilies: * Acrotrichinae * Cephaloplectinae *

Ptiliinae Ptiliinae is the largest subfamily of feather-winged beetles (family Ptilidae). About 80% of the described genera of these very tiny beetles are contained herein; however, many more genera and species In biology, a species is the basic u ...

References

External links

*
Family description on Tolweb
Beetle families Staphylinoidea {{Ptiliidae-stub