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Related to Ephemeroptera: Diptera, May fly, Trichoptera, shadfly


(invertebrate zoology)
The mayflies, an order of exopterygote insects in the subclass Pterygota.



(mayflies), an order of winged insects having two similar winged phases, the subimago and imago, which are separated by a molt. During these phases, which have a duration ranging from several seconds to several days, the insects do not feed. Some species live for only one day.

The mouthparts are vestigial, and the alimentary canal has been transformed into an air bladder. The forewings have a rich network of venation and are larger than the hind wings. Sometimes hind wings are absent. The tip of the abdomen has three segmented filaments—a pair of long, lateral cerci and one median paracercus, which is sometimes much shorter than the other two.

The mayfly undergoes incomplete metamorphosis. It has a large number of larval stages (as many as 25), and development takes place in the water for one to three years.

There are 23 widely distributed families, embracing more than 2,000 species. The USSR has 17 families, with more than 200 species. Mayflies all inhabit freshwaters, but they represent various ecological groups and have adapted to various living conditions (undergrowth, mud, rapids, soil). The larvae are food for many valuable commercial fishes, including salmon and white-fish. Ephemeropteran fossils are important in stratigraphy.


Opredelitel’ nasekomykh Evropeiskoi chasti SSSR, vol. 1, pages 110–36. Edited by G. Ia. Bei-Bienko. Moscow-Leningrad, 1964.


References in periodicals archive ?
014 Table 2--Results of two-way analysis of variance (ANOVA), as Fvalues and significance levels, for seven macroinvertebrate taxa; total macroinvertebrates (all taxa combined); the combined percentage of Ephemeroptera, Plecoptera, and Trichoptera (%EPT); and three diversity indices (Margalef richness, Pielou's evenness, and Shannon-Wiener diversity).
The greatest taxa richness was recorded for Trichoptera (11 taxa: 10 species and 1 genus), Mollusca (11 species) and Ephemeroptera (11 species).
Percent Ephemeroptera, Trichoptera, and Plecoptera (%EPT) (Equation 4) for each sampling event was also calculated as these taxa are sensitive to sedimentation and changes in benthic habitat due to stream degradation (Zweig and Rabeni 2001).
Whereas the community structures of most of the pans consist mainly of crustaceans, the invertebrate fauna at pan 3 is made up of aquatic insects (including many Hemiptera, Ephemeroptera and Odonata).
Ephemeroptera recorded their complete absence at St III and IV while comparatively more density of ephemeropterans at St I (4.
Although Mayfly is the common name of ephemeroptera, chaoboridae and chironomidae are referred to as mayflies by the villagers simply because of their spectacular characteristic month of May emergence.
En las trampas de caida se recolectaron ejemplares pertenecientes a Ordenes no identificados en los contenidos estomacales, como Ephemeroptera, Opilionidae y Thysanoptera.
1) Ephemeroptera, Plecoptera, and Trichoptera taxa (EPT)--These taxa are typically less tolerant of perturbation than many other taxa.
Chironomidae and Culicidae), 1 family of Ephemeroptera (Baetidae), and several Crustacea.
The remaining 15% of specimens were in the orders Hymenoptera, Lepidoptera, Trichoptera, Orthoptera, Neuroptera, Thysanoptera, Ephemeroptera, Collembola, Odonata, and Mantodea.
Larvae of several insects, including Trichoptera, Ephemeroptera, Coleoptera, Plecoptera and Lepidoptera, have been reported to be part of their diet (Moffet 1970, Riguelet 1977, Naranjo and Avila 2003, Ceron et al.
For northern studfish, non-culicid diptera comprised at least 40% of the diet each month, except during July and August when ephemeroptera, coleoptera, and other prey items (gastropods and nematodes) accounted for the majority of consumed prey items.