Ephemeroptera (ephemeroptera) belong to Insecta, known as the "Ephemera", referred to as "wasp." Title ephemeroptera from the Greek εφημερο?, Meaning "only one day of life." Ephemera's French title (ephemères) also stems from this. The title in German (eintagsfliegen) is "One day into the life of the insect" means. In English, generally known as mayfly mayfly, that a large number of its regular occurrence in the spring and summer. Mayfly emergence has a timeliness, mostly in spring and autumn. And populations tend to focus on emergence time, usually spring and summer dusk. So sometimes the water will see the top of a large number of mayfly in the fly. Ephemera adult life is short lived, usually hours to days, more than ten days is minimal. Molt of the adults just to be mating, immediately after the majority of male to die after spawning females also died. After the death of a large number of mayfly falling water almost the same time, a good aquatic bait. Perhaps it is the beauty of ephemera, a very short adult life, and sometimes the surface of a large number of dead will be the ephemera floating in ancient times, such "short-lived insects," has aroused great attention, as philosophers and scholars lamented the very Yonghuai good stuff. Also, because the old ephemera and unique, it is a class of existing living fossils of winged insects of the origin and evolution of valuable and, therefore, become the workers of biological systems, the importance of learning objects.
Translated by Google
Ephemeroptera of the World History
世界蜉蝣目研究简史
After this, the United States edmunds, traver, France, and Russia's tshernova demoulin and part of the world for its own type of coverage. In 1976, edmunds et al. Also published the mayflies of north and central america, were listed in the North American total of 17 families and 24 subfamilies of mayflies are 622 kinds of 68. After this, edmunds, and peters, mccafferty continue to engage in research in this area. Present a more consistent understanding of subjects about 25. According to hubbard (1990) statistics, there are 310 extant and 61 fossil genera. mccafferty et al. (1989) estimated that about 2 250 species worldwide. One after another in recent years some reports, all types is estimated that no more than 2 500 species. Insecta Ephemeroptera in on the system status, there are many arguments (soldán, 1997; Liang Aiping, 1999). kukalová-peck (1968,1978,1983,1985,1994) and hennig (1981) and Odonata Ephemeroptera that are close to extinction of the ancient and common form of ancient wing wing sub-class of the Ministry of palaeoptera, go in a wing of the Ministry of pterygota , the location between the clothing and the new wing of fish head zygentoma between Asia Department neoptera. Head of Internal class on developmental aspects of the system, although there are some suggestions, but none is widely accepted, the author's views are often changed. There have been some use of cladistics method is a subject or some group within the study; the order level in the subjects research that claims to use of cladistic methods known to have four (mccafferty & edmunds, 1979; mccafferty, 1991; tomka & elpers, 1991; kluge, 1998), working with the analysis software algorithms have yet to see. The main reason for the formation of different points of view on some characteristics of each have a different understanding of weight, especially in how to treat and deal with adult and larval characteristics of understanding of different aspects.
Translated by Google
A Brief History of Ephemeroptera of China
A) The habits of ancient people observed Ephemera "Ephemera" first appeared in the "Book of Songs Cao" in the "Ephemera" poem (which may be in the reign of Cao Zhaogong BC 661 - 651 years BC). The poem: (Preface), "Ephemera" thorn extravagance too. Zhao Gongguo small force, not automorphic. Luxury and any good villain, will Rootlessness Yan. Ephemera of the feathers, clothes and distinctly. Heart worry men, and in my depart? Mayfly wing, t_set_se clothes. Heart worry men, and in my interest rate go? Ephemera dig reading, Mai snow. Heart worry men, and in return I say? The most obscure poem is the last sentence. According to Zou Shuwen (1956) research, "dig reading" is a double-stack rhyme sound the same, "read", that face, and with a few lines of "the feather", "Wings" counterparts. The blue-Ju Sun (1982) and Chen child development (1983) have interpreted this as a "change in appearance" and more a verb, the explanation does not seem to Zou Shuwen good. Both of them the last word on the poem "that" the interpretation of the "break." Poetry and poems from the sequence content, the poet is a beautiful and short-lived mayfly through to satire on current affairs, expressed the concern towards the evening not guaranteed. See the poem "Ephemera" that is the purpose of the present ephemeroptera Insecta insects, it will be the head translated as "Ephemeroptera" is the (Zou Shuwen, 1956,1981). As history of the "Book of Songs" explanation after another, so the ancient times, many people have had the account of mayfly and research, but unfortunately no detailed description of the form. "Ya" may be established in the Western Zhou Dynasty (1027 BC the beginning). Since its founding, until the Western Han Dynasty, which lasted over the years, during which continue to be updated. In, "said the worm" the ministry said: "Ephemera channel slightly." Xunzi (third century BC people) "Xunzi Ontario Chapter": "do not eat who does not drink, Ephemera also." Mao Heng (second century BC people), "Biography of Mao": "Ephemera, Drainage slightly also. Ephemeral, worse than the wings to self-modification. Spotlessly clean, clear appearance. T_set_se, many also. Dig reading, content reading too. snow, made Xianjie. " Xihandaide (93-49 BC) "Summer is small": "May mayflies are Yin. Yin, the public also. Ephemera when Yin. Ephemera who channel a little also, toward the twilight born dead, what is also there See also. " San Guowei States Ruan (early third century AD) "Chanting": "Ephemera play three dynasties, t_set_se repair wings." Guoyi Gong Jin dynasty (third century AD, people), "Kwong-chi": "Ephemera to burn even more difficult, the United States in the cicada. Mayfly Xiran students in the water, cover water, commit suicide, with the flow away." Jinchao Fu Xian (AD 239-294), "Ephemera Fu": "read poetry to the ephemera, though ephemeral sense of their, and to repair its wings, can Hing, then Fu. Yousheng thin, is said Ephemera . Yu slightly the humble quality, Private candidates Keung t_set_se. does not know the dark moon, no intention of Spring and Autumn. to take full day, yet they want anything else? opera commissioned by the stagnant water flooded over, but why arena tour. " Ling Tang, "Thanks for the Memories": "pleasure deep pool fish, bird habitat like the boughs, sigh Seoul ephemera Yu, Yi He for the death of a prince death of a prince?" Song Su "Literary Works" (AD 1082): "Send a mayfly in the world, vague drop in the sea." Ming Liu Chang: "the county explore Shicaiaowu Suo trunk": "Tang Jiagong sub hi boast brag, as if to shake the tree Ephemera." In addition, the Qing Meng-Lei in the "ancient and modern integrated poultry pest Code Book" (AD 1726) and the Japanese Gang Yuan Feng (AD 1784) in "Mao Pin Wu, map test" ephemera also plotted (Figure 1.1, Figure 1.2). From the foregoing, ancient history and living habits of mayflies observed the appearance is very subtle, ephemera is a clear indication of a very short life, insects, living in the water, drifting with the water after death. Ephemera look beautiful but very weak. Visible observation of the ancients is in line with reality. But at the same time, some of the ancients may speak different dialects of the reason, but will "Ephemera" misinterpreted as a class of beetles or moths, so Zhu Hong complex, high-Jin Sheng (1950) still may be a beetle that the mayfly. Such as: Lu Wu-chi three people (the early third century AD) "Mao insects, fish, vegetation, sparse": "Ephemera, Fang dialect also. Pass that the drainage a little. Like beetles have horns. As big as that, a long three-inches. A wing under can fly. summer rain from time to time in a month. modern people burned it, as beautiful as the cicadas are. " Jinguo Pu (early fourth century), "Ya Note": "(Ephemera) like insect pest Qiang Ji, narrow body and long, angular, yellow and black. Agglutinative dirt, the ephemeral. Entice good pig" . "Fairy Poem": "I ask Ephemera generation, Hok Ning known turtle." His "Ya tone map" graph also plots the mayfly. Brief Account (AD 642) "Mao justice": "Guo Pu Yue (Ephemera) like insect pest Qiang Ji, narrow body and long, angular, yellow and black. Agglutinative dirt, the ephemeral. A good taste of the pig. Lu Shu-chi cloud, ephemera, dialect side also. through the channel that a little. like beetles have horns. as big as that, three-four inches long. A fly under the wings. summer rain from time to time in a month. people today burn Sunburn of the United States, such as cicadas too. Fan scorpion light that the insect feces, with whom ephemeral when rainy. " Dian Lu Song, "interpretation of soil insects Peel Ya" (AD 1125 preface of his son): "(Ephemera) insects like beetles can fly. Burn the taste of, the United States, such as cicadas also. Xiran students. Cover water, commit suicide, with the flow. " Dai Dong Song (AD 1241-1276), "Six Categories": "Press said the mayfly wings to revive poetry, clothing t_set_se charm charm, although beetles feathers, chanting terms should not care a feather. Zi Yan Ephemera do not drink do not eat, eat dirt channel a little attack, nor those who do not drink do not eat too. ephemera cover feather worms, suspect the armyworm. litura pink wings, such as butterflies and small, have more in April when the wheat fields in the rainy night, then fly flutter lights. not eating moth class, so its not a long time, similar to those so-called ephemeral. cover their food and it does not tumble, so that the mayfly is also evil. " Li Ming (AD 1518-1593), "Compendium of Materia Medica good insect pest Qiang APPENDIX Ephemera" (AD 1587): "Ephemera, a channel slightly. Like insect pest Ji Qiang and small, narrow body and long, angular, yellow Black, a wing can fly under. summer months after the rain plagued dirt, the ephemeral. a good taste of the pig. Sunburn who take food, as beautiful as the cicadas are clouds. cover Qiang mantis insect, mayfly, abdominal sterile insects, beetles, are grubs, beetles, scorpions are of this. is also good of the pest insects Qiang one, must know that too. or say Ephemera water bug also, the shape of silk moth. ephemeral. " Ming soil jin, Wang Enyi Sons (AD 1609), "ternary diagram will": "(Ephemera) shaped like beetles and small, angular, three-four inches long, yellow and black, back under the wings to fly. Burn and eat it, as beautiful as the cicadas too. Xiran students. cover water, commit suicide, with the flow. said drainage between Liang and Song Dynasty. profusion dirt, the ephemeral. a floating meaning, Gu Yue Ephemera also. "They also painted a mayfly map. (B) of the Chinese "Ephemera" and Ephemeroptera ephemeroptera the process of linking In China, "Ephemera" animal as a scientific term in 1891. Taught at Rocky Mountain Station in Wuhu Museum of American missionaries with the instruments to China John in the "Scientific and Industrial Magazine," published in the sixth year of the "worm School On" in "the subhead of" part of a "Class XI Ephemera" , painted a worm, for example, and to note a few lines (Zou Shuwen, 1981). From the overall style of this article and the translation of terms and the background, it may not be translated from Japanese. "But most of the terms used in the book is different from the modern ... ..., coupled with" investigation of things compiled "major distributors around the consulate, the tax office and chapel, all fresh for the general public, and thus have little effect on academic research in China." (Wang Siming Zhou Yao, 1995) Zoushu Wen (1956): "The Japanese scholar this name as ephemeroptera (Ephemeroptera) the name of a insect, China has consistently adopted today Entomology, which is right." In fact, as early as 1908, Shen-dimensional minutes to write: "... ... (Ephemeroptera) occur in real water, cover the larvae to be in the water year or two, and then change. Changes, somewhat similar form of moth, but the end of a filament end of three long times its body. borrowed, you can float the surface. actions such as shooting, hence the term. ... ... Today, scholars mayfly is also called molars. ... ... shows off ephemera of a class of non-beetles. ... ... "can be seen: Shen-dimensional bell description may be translated from Japanese books; He is the first morphological description of China as a mayfly, although description is very simple; he explicitly rejected some of the ancients misinterpretation of ephemera. 1923 published "Dictionary of Zoology" (Du Yaquan et al) in the "Ephemera" is also marked with the Japanese article. In summary, Zou Shuwen say 1956 is right. (C) the purpose of scientific research in China Ephemera To the scientific method first report on China ephemera British walker. In 1853 he published a cloeon sinense (when he was named caenis sinense). Then eaton (1870-1892) in China has reported the distribution of two kinds of ephemera. mclachlan in 1904 reported 1 species. After 30 years in this, our study the emergence of a mayfly climax. German ulmer (1912-1936), Spanish missionaries navás (1922-1935) described many new species in mind, then, Mr. Xu Yinqi (hsu yin-qi ,1932-1938) The mayflies of China has been systematically studied, Hu Jingfu (1935 ) in the "List of Chinese insects," Statistics of China in the 41 species of mayfly are known to remove navás unnamed, and is actually 40. ulmer (1936) statistics, 47 species of mayfly, Xu Yin-Qi (1937-1938) statistics, 64 species, and describes five new species. Ueno Japanese interest c (uéno) reported in 1928 and 1 species reported in Taiwan in 1931, 12 mayfly species, which in the above list are not found in ephemera japonica mclachlan, ephemera supposita eaton, epeocus psi eaton, ecdyonurus hyalinus ulmer, rhithrogena vitrea ulmer, isonychia formosana ulmer, pseudocloeon kraepelini klapálek a total of 7 species. He (1941) also reported that the 5 in Northeast China ephemera, including ephoron virgo (olivier 1791) and oligoneuriella rhenana (imhoff 1852) is in China at that time new records. In addition, the Japanese Matsumura sickness (matsumura, 1933) reported that one kind, another Japanese Kam this West Division (imanishi, 1940) also reported some of the ephemera in northeast China, but most are not named. After sorting and naming descendants, now known there are 10 still not past statistics (bae, 1997; bae & liu, 1999). Remove the different names, in the liberation, China has known 88 kinds of ephemera. In 1942-1978 years, the domestic ephemera of a standstill. Internationally, with only scattered on the Northeast China, Hong Kong and Taiwan Province, Yunnan Province ephemera study reported a total of 6 species. gillies et al. (1949,1951) collected from China named Hong Kong's cloeon harveyi and isca purpurea. In 1972, tshernova Yunnan, China reported a vietnamella ornata, and in 1973 reported ephemera strigata distribution in China. 1963, peters et al. Reported that China's Hong Kong one kind habrophlebiodes gilliesi, tsui and peters reported in 1970, nymphs of the species. Ueno benefits III (1969) reported from Taiwan and Hong Kong China 6 ephemera, including baetiella japonica (imanishi) was first discovered in China. From the 60's, Mr. Xu Yinqi Nanjing Normal University led the students the purpose of re-classification of Ephemeroptera, work, and in 1978 began to publish a new species. So far, the mainland reported a large number of mayfly, which Guihong (1985) on the previous work carried out statistics, a total of 96 (remove synonyms and fossil species, is actually 92), by You Taishou and Guihong ( 1995) completed the "Economic Insect Fauna of Ephemeroptera", the preparation of a detailed description of 101 mayflies. Another Korean study in 1991 bae River Branch potamanthidae flower wasp, the reports produced in China, two new species. braasch & soldán (1980) reported one. In Taiwan, in 1981, braasch will ulmer reports distributed in Taiwan epeorus psi eation (1885) to epeorus erratus. In 1985, müller-liebenau reported the mayfly families baetidae Taiwan four new species of 6, the same year waltz & mccafferty also reported one. Kang S C. equal to the 1994-1996 classification of the ephemera in Taiwan made a lot of work, published 46 new species. In addition to these new types of reports are nymphs epeorus erratus as a model outside the specimen. In summary, according to statistics, the end of 2001, China has reported 256 Ephemera (Table 1 and Table 2, some types of local history is not included in the statistics mentioned). tshernova et al. (1986) mentioned the distribution of the species because China did not indicate the specific sample collection sites and not included in the statistics. braasch (1999) reported that the Chinese ephemera for the tshernova et al. (1986) and some have been reported in local history, not seen in this study specimens were not involved. Insecta Ephemeroptera in the phylogenetic position Insecta Ephemeroptera in on the phylogenetic position in a variety of perspectives (see kluge 2000). These views are basically around the "ancient wing class" started monophyly. "Ancient wing class palaeoptera" was first proposed in 1922 (see kluge 2000), including Ephemeroptera, Odonata and some of the extinct Paleozoic insects, and the new wing class neoptera counterparts. To the existing Ephemeroptera and Odonata of view, following the ancient characteristics of common and unique wing class: adults can not be stopped when the wings folded back cover in the abdomen, but can only be erected or Stretch in the body back; wings with complex intercalary vein; before and after the wing shape and the pulse phase is the same; adult antennae wiry; immature aquatic; larval jaw internal and external jaw leaf healing, abdomen with gills (all mayflies and some dragonflies), etc. (hennig, 1969; kukalová- peck, 1991,1997; wheeler et al., 2001). However, these features only identifying features of the ancient winged class, not necessarily the mayfly and dragonfly synapomorphies. Wing of the current class of students all over the ancient synapomorphies awareness lead to three different perspectives (hennig, 1981; kristensen, 1981; soldán, 1997; wheeler et al, 2001). The first view is that the old wing type is a monophyletic group, which has a range of dragonflies and mayflies synapomorphies formed a sister group. hennig (1981) proposed four synapomorphies are: wing veins with a complex leap, adult antennae wiry, immature aquatic, larval leaf jaw jaw internal and external healing. However, these four synapomorphies there are people in each of the questions raised, which kristensen (1981) criticism of the most typical: a complex ancestral veins is likely to sign, the shape and the antennae parallel evolution of aquatic habits may is very large, and the characteristics of the jaw may not meet the common mayfly patterns. The second view is that there is no Odonata and Ephemeroptera synapomorphies, not a sister group relationship. But Ephemeroptera and (Odonata + new wing class) as a sister group relationship. kristensen (1981) cited a class of Odonata wings with seven aspects of the new synapomorphies: adult stage does not molt, after the pass into the chest of the foot in the trachea and wing sections from the two bodies, abdominal muscles and the stomata closed stomata directly connected piece of bone, r rs clock pulse with a total handle, a single female's gonopore, developed in the tongue, the first part of the chest muscles disappear. In addition, a series of features can be Ephemeroptera and other winged class distinction between (soldán 1997), such as the larval upper jaw of the sliding joints, abdominal end of a long section of the tail wire, wings with shoulder cross veins (subcostal brace or humeral crossvein brace) and after hip and elbow clock pulse a cup formed at the connection point pulse weaknesses (bulla), female-style terminal nourish the ovaries, sperm flagellar axoneme of 9 + 9 +0 type (baccetti et al. 1969). This view is also supported by some molecular evidence (wheeler 1989; wheeler et al. 2001). However, this view has been kukalová-peck (1997) refuted one by one, the other main proponent of this view point kristensen changed in 1991. And, from the wheeler et al. (2001) observations that, just from the 18s rdna sequence results support the first view, but the form of merger analysis and molecular evidence, they obtained a second opinion. I believe that this form of feature _select_ion may be relevant, because for the analysis of the characteristics extracted from the relevant literature, and to support the second view of the morphological characteristics of relatively high. In addition, because of living dragonflies are very specialized (such as predatory behavior, mating, etc.), its own synapomorphy is very large, sometimes difficult to compare with other insects. Meanwhile, a series of ancestral signs Ephemeroptera (and may also be the only extant insects some of the characteristics), they may have been a number of distinctive features, is sometimes difficult for phylogenetic studies. Each of these three perspectives have some evidence, but also are subject to various criticisms. Careful analysis of the evidence supporting the view, we can see, these features are groups of living insects, possess, and aquatic insects are most highly specialized groups, some of the original features have been difficult to identify. On the ephemera of view, the adult wing base bone pieces have been unable to identify. The same time, due to the long evolution, extinction of many intermediate types, winged class characteristics within the target interval between the relatively obvious, sometimes difficult to compare. Furthermore, a wide variety of insects, various adaptive are possible, the views of each can be found opposite. Wing on the phylogeny of ancient studies, kukalová-peck views self-contained, needs to be carefully considered and carefully analyzed. The author believes that some of her views has the following characteristics: 1) the Hexapoda and arthropods as a whole to consider the formation of a unified system model, rather than separated their research, which fully take into account the evolution of a common origin factors; 2) insect body parts into a unified model of the Community section. Information, whether ancient or extant insect insect features, the insect body segment is the result of evolution, they should have a common origin; 3) full use of the fossil evidence. However, wheeler et al. (2001) proposed kukalová-peck of the fossil evidence is difficult to identify. In general, experts have many years of research experience, fossils can still be identified, as long as they are well enough preserved. In addition, fossil insects generally relatively large, if preserved, may be more recognition feature. Furthermore, the large number of fossil insects, research can provide sufficient information on the ancient characteristics of insects; 4) that the existing organs of various insects have mostly not new, but by evolution or degradation from the original organ, such as mayfly nymphs various appendages, in the end of the gill filaments of silk, and the first chest, shoulder wing cross and the evolution of the source dyke in her body section model can be explained; 5) taking into account the topography, climate and individual development information; 6) of the major groups of winged insects, the phylogenetic relationships between the inevitably have to face and resolve the origin and evolution of insect wings, and their resolution depends on the resolution of the following five issues: the origin of wings and flight ability to obtain, and various abnormal types of abnormal origin of the relationship between the evolution of wing veins, wing base and wing bits of bone-chip evolution, evolution of appendages. In the original insect kukalová-peck mode, the above aspects can be relatively uniform interpretation. kukalová-peck (1978, 1983, 1985, 1991) proposed a class Insecta of the original model, and in 1997 made a further explanation for its support of the ancient wing type is monophyletic view. She (1978) pointed out that the wing is used to limit or distinguish the ancient and the new class of three main features of the class wings (wing position, wing fold and wing base bone surface film) in fact are not comparable, because the type of living of ancient and new wings wings are wings like insects from the Paleozoic on the basis of the original wings evolved is synapomorphy, which are in different directions by the same features of evolution. The main features of the original model wings: wings have at least 8 pairs of longitudinal veins, each of the first clock pulse of a convex, concave, after a clock, punch clock face showing white wing folds arranged like leaving. In the wings around the base of a horseshoe, surrounded by a bone chip _set_, each piece of bone structure and shape roughly similar. A total of 32 pieces of bone, composed of four 8 lines, each line corresponds to a pair of longitudinal veins. With the evolution of the Ephemeroptera of these bone slices, and the new wing Odonata occurring in a different class of healing. The purpose of Ephemeroptera and dragonflies, similar to wing base for the degradation and healing of bone slices in the base to form two large wings of bone plate (platform, they contain pieces of bone may be different), but in the new wing wing base bone class film less healing, resulting in the wings play a key role in the folding process axillary piece, another muscle attached to form a joint leaving wings can be folded (kukalová-peck 1997). Although the ancient winged insects on the wing can not be folded, but the same class with the new wing, evolved this model is still a feature, it is not that the new wing is a wing like the wings of ancient wing class evolved. She (1997) that the ancient and the new wing wing type class in the following areas is a fundamental bifurcation: the ancient winged wings before and after class in terms of shape and phase are similar vein, m pulse with a trunk, cu vein trunk, and there is always hip cross-vein (anal brace) and aa membrane of clock connection. In addition, the ancient wing wings like the usual rules-based bone slices are arranged close to the cu sc wing veins of the two base pieces of bone healing, the other veins at the base of the bone slices are closely twisted together. More ancient than the first outer wings are a new class of its own levy. Larvae inside and outside the jaw jaw healed leaves the chest and the web transfer section of incomplete healing and expansion of the abdomen is also a web of ancient wing class of its own new levy. The new wing of its own new levy type: front wing significantly different from the protective effect of the main wing, narrow and thick, and after the flight from the role of the main wing, thin and wide; with different types of ancient wing, wing vein into two groups aa ; conjugate vein area in the ventral membranous fold; hind wings hip - yoke area expansion, with distinct fold lines, hip cross veins formed by the bone slices and a1. Mayfly and dragonfly wing vein on the synapomorphies are: m cu clock pulse and a trunk, cup veins simple; wings with rp-ma, m-cu, cup-aa1 three important cross-veins; rump long, curved cross-veins. Mayfly and dragonfly synapomorphies include: wing base healing of bone slices leaving the formation of two bone plate fin can not be folded, longitudinal veins between the y-type with complex intercalated veins and cross veins hip cup connected with the formation of weak pulse (Ephemera) or wings Results (dragonfly) (kukalová-peck 1997). Recently, molecular phylogeny for this study provides new information. wheeler (1989) and under rdna wheeler et al. (2001) Comprehensive gene sequences and morphological features that Ephemeroptera, Odonata relationship with the new wings of Ephemeroptera class + (+ new wing class Odonata). However, hovm? Ller et al. (2002) more groups based on gene sequence analysis, the ancient wing type is monophyletic. As far as known genes related to the ancient wings, little amount of information (especially ephemera, see genbank), is difficult to judge which one is better, so molecular evidence for further testing. The author believes that to resolve the phylogeny of ancient wing class, we should first solve the problem of insects kukalová-peck mode problem, and mayflies and dragonflies are excellent experimental material. If, as she stated, students are sub-adult mayfly is the original number of centralized or relics age, I wonder if there are still two or more "sub-adult stage," the mayfly species, or insects. Perhaps South America, Australia or Southeast Asia-depth study of mayfly species will have another heartening results. In addition, according kukalová-peck of the original model, chest and abdomen sections are insects with one pair of wings (or gills, or similar structure) and a pair of appendages. In particular mayfly nymphs, his chest three buds each with a pair of wings or the remnants (such as ecdyonurus, dolania is) and the other with a 1 on the foot. However, in the extant mayflies and dragonflies, for I know, have not found the abdomen with the same time with one section of the types of appendages and gills. I do not know whether that future research of this type of insect. The insect in nature exist? If there is, and now still exist? Different mayfly species, nymphs of the jaw, lower lip, three pairs of legs at the base of the gill filaments may each have a bunch of (sys & soldan 1980; zhou & peters 2003; muller 1985). These gill support kukalová-peck insects mode. The discovery of more primitive insect wing for the class of the ancient provide direct evidence. Fossil evidence kukalová-peck play a key role in the original model. More fossils were found intact ancient wing class may provide a new phylogenetic evidence. Molecular evidence currently is still not enough. As more genes of ancient wing mitochondrial genome sequences and determination of categories for the study of ancient wing to find more evidence of more positive elements. Although the winged insects, Ephemeroptera in the exact phylogenetic position is still no conclusion, but a basic fact can be sure that the mayfly is wingless insects with winged insects, the link between the transition is the more primitive winged insects the groups.
Translated by Google
Morphological and biological characteristics
1 morphology Pulse phase and 1.1 fold wing surface Ephemera existing longitudinal wing veins include: leading edge of pulse c, front sub-clock sc, vein diameter r, the former in the vein ma, in the vein of post-mp, before the elbow after elbow clock pulse cua and cup, hip clock a. In addition to longitudinal veins, most of the group also has a network of cross veins. In addition, the wing leading edge also with a sub-aortic arch (subcostal brace), and the margin of a variety of Run Run clock pulse. Ephemera show more or less around the wing-like folds, that is kind of like a folding fan uneven. In addition, the ephemera and rs sc clock pulse is sometimes a very obvious weaknesses. Generally believed that the phase is very close to the original pulse mayfly insect clock phase. kukalová-peck propose a primitive insect wing vein pattern (kukalová-peck 1991). In this mode, the insects on the wing with 8 pairs of longitudinal veins, respectively, before the clock edge pc (pca +, pcp-), the leading edge pulse c (ca +, cp-), Asia-edge pulse sc (sca +, scp-) , diameter of vein r (ra +, rp-), the pulse m (ma +, mp-), elbow vein cu (cua +, cup-), hip pulse a (aa +, ap-), shoulder vein j (ja +, jp-) . Each of the first clock pulse of a convex, concave, after a clock, punch clock face showing white wing folds arranged like leaving. With the evolution of the Ephemeroptera, pc, c, and sca healing into today's leading edge pulse c. Sub-aortic arch by the sca + front evolved, it c pulse, sc r1 clock pulse and connected together. According to this model, ephemera is now veins relative to the original. Wings and wing joints 1.2 bits In the absence of bone pieces and the flight muscles, Ephemera in the stopped state can only be erected on the dorsal fin, but not the same class as the new wing to wing folded back in the chest and abdomen. This view found in a variety of information, but kukalová-peck believe that this view is not correct. She proposed that in the original wing winged insects around the base of a horseshoe, surrounded by a bone chip groups, each bone slice of the structure and shape roughly similar. The bone slices 4 8 lines, each line corresponds to a vertical vein. The bone slices contain blood vessels, the row closest to the existence of winged sinusoid, to eight longitudinal veins supplying blood (kukalová-peck 1991). In Ephemeroptera, the bone slices in different degrees of degradation and healing. Mayfly wing joint board by the current sc, r and m clock pulse at the base and the two adjacent pieces of bone healing from, cu, a, and j the corresponding base pulse twisted piece of bone in the joint board of the rear. Another two bone pieces of the ephemera in the Paleozoic, there are still, in the extant mayflies have been obvious (kukalová-peck 1983, 1997). Compared with the new wing class, mayfly insect wings based bone slices (three axillary sclerite ax sclerites) and the corresponding folding wings on the shoulder muscles and veins at the Zhehen (also known as conjugate fold jugal fold) still exist, but As the healing bone slices, these structures no longer work, so when the wing mayfly is support or oppose the party stopped upright in (brodsky 1970). Although the Ephemeroptera (ancient wing class) insect wing can not be folded, but with the new wing classes, this model is still a evolutionary characteristics. Accordingly can not believe that the new wing is a wing like the ancient winged class evolved. Appendages 1.3 In addition to antennae, mouthparts, legs and wings, the mayfly also has other appendages, such as the nymphs of the seven pairs of gills, tail clip and adult abdominal end of the long tail section of the two required. These structures come from? Whether they are homologous structures? Made under the kukalová-peck Hexapoda hexapoda foot raw mode, the original insects may be at least 11 feet, each section has a number of uncertainties inside and outside the limb suddenly. Existing wing mayfly larvae gills and for the first one (epicoxa) flat protrusion (flattened exite), and the first one around the outside itself into conflict (or wing) of the bone pieces. Ephemera's feet, tail clip, tail to be the two common origin with another, that is true enough. Ephemera's penis was the 10th abdominal segment appendages sudden turn in the section (trochanter endites). Some mayfly pereiopods the base of the base section of the base section of the gill is also equivalent to the conflict. And in the end of wire to the end of the 11th abdominal segment of an extension (kukalová-peck 1991; brinck 1957). There exist about the origin of wings several hypotheses, such as the origin of said backplane, said the origin and the needle protruding gill source said. According to the views of kukalová-peck, mayfly larvae gills of the abdomen and chest in the wings homologous (kukalová-peck 1978,1991). Because: 1. Some mayfly larvae gills wing shape and structure is very similar: thick ossification front, there is the trachea, both for the flat foliation; 2. Gills and fins are arranged by section, and both by the same muscle control, some mayfly's gills have a very strong activity; 3. mayfly nymphs of the head and thorax except absolutely no flat wings outside the gill-like structure; 4. gill and fin were born under the base section (subcoxa ) and the backplane between the valve on top; 5. Some adults in the abdomen of living mayfly like wings still retain the "gills" like remnants (? tys & soldán 1980). Ephemera fish probably originated in clothing zygentoma (Shi-Xiang 1955; Tan Juanjie 1980; wigglesworth 1973). They have a long section of the tail wire. Long wire to the tail section may be Ephemeroptera retained the unique living habits, such as the adults do not eat and the air full of the esophagus storage, body weight less, have a unique mating behavior (brinck 1957), long enough before the male adult and so on, in the air may have some role in maintaining balance (wigglesworth 1973). 1.4 mouthparts Sub-clover tongue and lower jaw and outer jaw within the jaw leaf leaf healing is believed to be one of the original features of mayfly (hennig 1981). 1.5 mouthparts and front foot at the base of the gills In addition to abdominal gills, but in the short silk Ephemeroptera mayfly mayfly of total branches and flat part of the total families in the species in the jaw, lower lip, front foot and the base of the foot with filamentous gills. This type of gill is also found in some Hymenoptera responsibility Woo, Odonata and Trichoptera (? Tys & soldán 1980). According kukalová-peck of interpretation, this type of gill is likely to be accompanied by the original base of the limb limb suddenly evolved (kukalová-peck 1991). 1.6 Xishangfuke leptophlebiidae atalophlebiinae subfamily compound eyes Sang Branch leptophlebiidae atalophlebiinae small mayfly mayfly upper part of the compound eye of the subfamily of small eyes and the square. In the arthropods, only some species of crustaceans crustacea square with small eyes. peters & gillies (1995) reported that this type is a derived trait of small eyes, small eyes and the original hexagonal traits (peters & gillies 1995). Why only on the characteristics of Ephemeroptera and crustaceans also appear to be in depth. 2 internal anatomy Wing within the trachea 2.1 whitten reported before and after the winged insects, Ephemeroptera by different pass into the trachea, the trachea from a valve inside the wing, then after the wing of the trachea from a valve. In other words, the source of mayfly wings strictly within the trachea in different body segments. This situation is very close to the original model, which is more than other classes with the original wing. In other winged class, before and after the two wings of the tube from the valve, before and after the wing leading edge of the pulse to pulse of the trachea in the valve from the front, and front and rear wing vein from the elbow vein to the hip after the valve (whitten 1962). 2.2 The circulation of blood within the veins Mayfly wings in the direction of blood flow and other insects there is no difference, but the wing out of the blood flow is interrupted. This exception may be the original wing base with a large sinus related. The fin base with a large sinus is a Paleozoic insects with original features (kukalová-peck 1978). 2.3 Reproductive system Fallopian tube with the end of AIDS Ephemera, part of the reproductive system are not affiliated glands, male and female gonopore opening pair in vitro, no ovipositor (landa 1969). According to general understanding, these are relatively primitive features. 2.4 sperm According baccetti et al. Reports and Liang Aiping (1999) review, two-winged mayfly wings cloeon dipterum (four mayfly families baetidae) within the sperm flagellar axoneme of 9 + 9 +0 type (baccetti et al.1969; Zhengyue Yi, in the final Hung 1999), and most insects is 9 +9 +2 type, individual type of type 9 +9 +1 (Diptera culi_set_a is). From sperm flagellar axoneme within the type of view, Ephemeroptera uniqueness. 3 Biology 3.1 of the original abnormal Mayfly's life cycle consists of four stages, namely egg, larval, sub-adult and adult. With all other winged insects difference is that sub-adult and adult mayfly has wings and flight capabilities. In other words, mayfly adult stage with two age, or adult stage 1 is still molting. And sub-adult mayfly nymphs and adults of very different shape, living in different environments, there are sub-adult stage, this type of metamorphosis metamorphosis often specifically referred to as the original. schaefer that sub-adult Ephemeroptera insects is an ancient mayfly of two or more adult molt of the evidence and relics (schaefer 1975). It is able to survive because Ephemeroptera insects, fully developed wings and the maturity of external genitalia is not synchronized and can not be completed in a molting process, but the first step in the sub-adult development and extension of the first wing, Step through the molt again to mature external genitalia. But in all other winged insects, these two aspects in a molting process is complete. Why only be able to save the ancient characteristics of mayfly? He believes that two different molting process and the different organs of the body of maturity is the result of the endocrine system are not synchronized, which is a primitive feature. Since the purpose of sub-adult mayfly and the adult stage of the very short time of emergence mayfly population is relatively concentrated, they do not need feeding adult stage (in ancient mayfly may only need very little), so they escaped the fate of the probability of prey large. In other words, _select_ion pressure is not large enough to make the same class with other winged adult stage molting frequency of compression, prompting a one-time access to adult feeding, flight, search for a mate, mating, egg shape and capacity, thus increasing the possibility of continued population and ability. CHEN Shi Xiang and Tan Juanjie considered equivalent to the entire adult mayfly metamorphosis sub-class of the pupal stage, so they think incomplete metamorphosis and complete metamorphosis are derived from the original abnormal: less sub-adult stage becomes incomplete metamorphosis, and evolution of sub-adult is a complete metamorphosis into a pupa (Shi-Xiang 1955; Tan Juanjie 1980). But kukalová-peck that all of the current Insecta types are derived from the metamorphosis is not abnormal type. Insects in her original model, the original winged type (including mayfly) nymphs to adults with no significant metamorphosis process, the occurrence and development wing is the gradual and progressive, and wing buds and chest moving between joints. Perfection requires a number of winged age, that is true of adults over the equivalent period before a number of sub-adult mayfly of the age. Today there is only one sub-adult equivalent of the original number of sub-adult age of the result of central or left (kukalová-peck 1978,1991). Molting frequency of 3.2 Ephemeroptera relatively large number of insects molt, estimated at between 10-50, most types of molt frequency in the 15-25 times (brittain 1982). kukalová-peck that in the Paleozoic, the original ancient wing class palaeoptera (including Ephemeroptera ephemeroptera) has extended the wing buds or wing, they are a unique development process. Nymphs bent backward on the wing bud, and adult extension to the side of the wing. Nymphs to adults in the development process, the wing buds gradually extend laterally, which requires several molting process. In the _select_ion pressure, gradually reduced the number of molting, and wings of the above changes are still necessary, and therefore appeared in the process of metamorphosis, that is in a molt molt many times before completion of the course completed the process of wing extension (kukalová-peck 1978, 1991. But some of the reservations in the ephemera of the characteristics of a number of molting. CHEN Shi Xiang, Tan Juanjie and some other people think, from the winged class pterygota clothing fish heads zygentoma, and clothes that are no abnormal type of fish, many times in the development process needs to molt. As a primitive and ancient group, retained the characteristics of mayfly (Shi-Xiang 1955; Tan Juanjie 1980). 3.3 mating behavior Ephemeroptera insects have a complex and unique mating behavior. Specific process is this: the first drill or male adult female adult fly ventral side, extending its obvious extension of the front foot, through the tibia and tarsus joint between the tarsus special rolled up from both sides of the hook adult female wing of the base; and abdominal support or oppose the top male adult bent, will be located in the 9th abdominal segment reversal genitalia ventral side facing up with the female external gonopore consistency (brinck 1957). Cause of this complex behavior is not clear. It is interesting stone insect C, dragonflies have a complex mating behavior (baccetti et al. 1969). 3.4 Aquatic Habits All extant mayfly nymphs are aquatic, from the perspective of fossil forms ephemera (such as the paddle-like tail, with gills or similar structure), Mesozoic aquatic mayfly has a habit of the (sinitchenkova 1984). So aquatic mayfly larvae of native traits or habits are secondary characters it? This issue involves the following issues: There are winged and wingless class have a common origin or with the class of crustaceans have a common origin, or whether it is a Hexapoda monophyletic? And how fin origin and evolution? 3.5 adults do not eat Sub-adult and adult mayfly mouthparts degradation, non-feeding function. Therefore, the sub-adult stage and adult stage of the required energy comes from the accumulation of nymphs. The only function of the adult mayfly task is to mate and lay eggs. In insects, the types of adults do not eat more, but as a whole, all members of Ephemeroptera are not feeding in the adult stage has a certain uniqueness.
Translated by Google
Morphological diversity of mayfly nymphs
蜉蝣目 蜉蝣稚虫形态多样性
蜉蝣目 蜉蝣稚虫形态多样性
蜉蝣目 蜉蝣稚虫形态多样性
1 general forms of mayfly nymphs 1.1 system 1.2 head Mayfly nymphs antennae length changes in different subjects in the larger forms from glabrous to dense hair ranging. Changes in compound eye and monocular small, but small mayfly families (caenidae) surface of some types of monocular highlight was like thorns. In addition, the lip base, the amount may be outstanding, the head may have a variety of conflicts and the angularis tumor. Mayfly larvae mouthparts are typical chewing mouthparts, the various parts may change, some changes are still significant. Which overshot teeth was the most common form. Predatory species are often well-developed upper part of the gear, and filter-feeding species is generally more developed parts of grinding teeth. Chest after the chest was 1.3 mayfly wing buds cover the back of the view can not be seen. 1 to 2 on the wings breast buds. Changes in the larger foot. Burrowing mayfly General Division of the main business of life, enough to tap the foot. This section of the legs and feet are very thick tibia, tibia angle of the front side of the prominent claw small. Mayfly nymphs flat Division wide and flat foot leg section, with fine hairs. 1.4 abdomen abdominal gills of the most striking feature is the diversity. Gills of the raw position, on the number, size, shape and other aspects may change. Abdominal back often with different spike and uplift. Some types of abdominal segment strongly back the lateral angle of the back side to highlight the extension. Variety of mayfly shape of the end of wire. Smaller in the type of activity, the tail relatively long sections of wire and thin, and the festival does not have hair, only two connections at a sparse hair. The ability to swim is often the type of wire on both sides of the dense hair tail, the tail has to be the inside of the long hair, hair woven into the adjacent end of wire mesh leaving the function of a paddle, in swimming generate power. 2 mayfly larvae habitat for convenience, the water environment can be divided into two categories, one for still water areas, one for the water district. Still Water District represented by lakes and ponds. Further, it may be the depth of still water above the light compensation zone area is divided into three categories, namely, hydrostatic water, sediment and the sediment surface. Each class has a different niche of the ephemera of life. Water areas to streams and rivers as the representative of this habitat can be divided into three categories, namely, water in water, sediment surface water area and the gap between the substrate. 3 in a variety of habitats typical of the type ephemera 3.1 The free-living type of hydrostatic water This type of ephemera, a larger compound eyes, the more developed muscles and tail movement. Streamline body, abdominal gills as the membranous sheet, single-thread or two; in the tail end of wire and wire near lateral sides of dense hair, leaving the end of the function of silk with a paddle, and the gills while swimming with splashing into the water power generated also can control the direction. Generally more slender claws. When not swimming, abdominal gills are often still shaking. Swimming meet in the abdomen and back along the body axis of the body placed foot rest extension, to catch hold in the water plants. Predator species in aquatic chironomids and mosquito larvae, but also feeding aquatic plants. Omnivorous majority. Typical of this type is the short wire wasp (siphlonurus), two winged wasp genus (cloeon) and so on. 3.2 Static surface water, which trapped wild-type substrate 3.3 Water District, the burrowing type of sediment 3.4 The free-living type of water area Surface water area of 3.5 adnate sediment type Body usually light green to brown. Body flat, the head is very wide and flat. The outside of the general ciliate upper jaw to be the end of a brush-like hair, the surface of the lower lip should also brush with thick hair. Type before and after the joint was full, it can only move forward and backward. The wide and flat foot leg section, tibia tarsus slender, its posterior surface and often densely hairy. Lateral abdominal gills. The back side of the leaf-like gills, fleshy; ventral side of gill filaments normally located in the back of the body, stretched out from the base of leaf-shaped gills. The leafy part of the gill-like suction cups to each other using the combination is conducive to absorption in the substrate surface. Some types 1 and 7 gill extends to the ventral body side, about two or close contact with gill contact with each other, so that the gills of the abdomen to form a suction cup-like structure of the whole (Figure 3.5). Wire on the tail are generally more sparse hair section between Central was born. Dark nature. Scraping the surface of the algae eating the food rocks. Able to swim, swimming, splashing into the water mainly by the gills. State of life can see the gills shook. Mayfly families on behalf of the flat type, which is a flat wasp (heptagenia), Gao Xiang wasp genus (epeorus), River chin wasp genus (rhithrogena) the most typical. Water area of 3.6 dwelling type substrate gap This environment there are two types of mayflies. A class of aquatic plants living in water areas and litter in a class of living in a crack in the rocks. Gap in living in the river stones flower wasp families (potamanthidae) as the representative of the type (bae & mccafferty 1994). Generally flat body of such ephemera, is light yellow to reddish brown. Palate with a distinct upper teeth, upper teeth and hair, often with teeth. Foot section of each leg is relatively wide and flat, while the tibia is slender cylindrical tarsus. Before the hind tibia and tarsus of the back side of the inner edge of dense hair. Lateral abdominal gills, 1 gill degeneration, and 2 to 7 and the mayfly gill shape very similar to the total subjects, but at the side of the body. Back surface of the abdomen with a variety of markings. The end of the base and end silk smooth, but with fine hairs on both sides of the middle. Swimming power stronger, filter-feeding. Above classification is not strict. Living environment for each type of ephemera, nor immutable. One type of water areas often were found in still water, but water still water area types in the area is very difficult to find. Overall, the choice of each habitat type still strict, when collected in each habitat, and its representatives are often the highest detection probability. 4 understand the form and related mayfly nymphs significance of habitat Compared with adults, mayfly larvae show greater morphological diversity. The classification and identification of a variety of forms to provide a very useful material. Little change in some types of adult forms, such as the four mayfly families, small mayfly families, small mayfly mayfly Section and Branch River flowers, different larval species comparison of the types of identification is often very effective. By representatives of each habitat type morphology of understanding, according to external morphology ephemera, it can generally infer the living environment and feeding habits. A variety of mayflies have relatively strict habitat _select_ion, in the acquisition process in order to improve collection efficiency, it should be as much as possible in different aquatic environments to collect a small sample. At the same time, it should address the activities of all kinds of ephemera with different ability to take a different collection methods and techniques. For those who live concealed and the type of activity is not strong, in the process of collecting samples, have enough patience and time to wait for them to come out from the shelter. While the type of activity is very strong, often difficult to easily adopt the need to _select_ the trawl or cages and other necessary specialized tools and the relative number of the collection. Mayfly nymphs because there is diversity in form, can infer the existence of certain mayfly nymphs plasticity, that is, under the action of natural _select_ion, different from the same branch of the ancestral larval form may be some diversity, such as small mayfly Section nymphs have three main forms: a long-haired type forefoot, monocular thorns and Normal. If the number of ancestors from different branches choose the same living environment, they may be on the external morphology showed a high degree of consistency or convergence. Therefore, in the reconstruction of phylogenetic relationships, larval feature _select_ion should be very careful. As different mayfly species and their morphology and their small environment and aquatic life are closely related to living habits, therefore, mayfly nymphs in the water quality monitoring has been widely used.
1 general forms of mayfly nymphs 1.1 system 1.2 head Mayfly nymphs antennae length changes in different subjects in the larger forms from glabrous to dense hair ranging. Changes in compound eye and monocular small, but small mayfly families (Caenidae) surface of some types of monocular highlight was like thorns. In addition, the lip base, the amount may be outstanding, the head may have a variety of conflicts and the angularis tumor. Mayfly larvae mouthparts are typical chewing mouthparts, the various parts may change, some changes are still significant. Which overshot teeth was the most common form. Predatory species are often well-developed upper part of the gear, and filter-feeding species is generally more developed parts of grinding teeth. Chest after the chest was 1.3 mayfly wing buds cover the back of the view can not be seen. 1 to 2 on the wings breast buds. Changes in the larger foot. Burrowing mayfly General Division of the main business of life, enough to tap the foot. This section of the legs and feet are very thick tibia, tibia angle of the front side of the prominent claw small. Mayfly nymphs flat Division wide and flat foot leg section, with fine hairs. 1.4 abdomen abdominal gills of the most striking feature is the diversity. Gills of the raw position, on the number, size, shape and other aspects may change. Abdominal back often with different spike and uplift. Some types of abdominal segment strongly back the lateral angle of the back side to highlight the extension. Variety of mayfly shape of the end of wire. In the smaller types of activity, tail relatively long sections of wire and thin, and the festival does not have hair, only two connections at a sparse hair. The ability to swim is often the type of wire on both sides of the dense hair tail, the tail has to be the inside of the long hair, hair woven into the adjacent end of wire mesh leaving the function of a paddle, in swimming generate power. 2 mayfly larvae habitat for convenience, the water environment can be divided into two categories, one for still water areas, one for the water district. Still Water District represented by lakes and ponds. Further, it may be the depth of still water above the light compensation zone area is divided into three categories, namely, hydrostatic water, sediment and the sediment surface. Each class has a different niche of the ephemera of life. Water areas to streams and rivers as the representative of this habitat can be divided into three categories, namely, water in water, sediment surface water area and the gap between the substrate. 3 in a variety of habitats typical of the type ephemera 3.1 The free-living type of hydrostatic water This type of ephemera, a larger compound eyes, the more developed muscles and tail movement. Streamline body, abdominal gills as the membranous sheet, single-thread or two; in the tail end of wire and wire near lateral sides of dense hair, leaving the end of the function of silk with a paddle, and the gills while swimming with splashing into the water power generated also can control the direction. Generally more slender claws. When not swimming, abdominal gills are often still shaking. Swimming meet in the abdomen and back along the body axis of the body placed foot rest extension, to catch hold in the water plants. Predator species in aquatic chironomids and mosquito larvae, but also feeding aquatic plants. Omnivorous majority. Typical of this type is the short wire wasp (Siphlonurus), two winged wasp genus (Cloeon) and so on. 3.2 Static surface water, which trapped wild-type substrate 3.3 Water District, the burrowing type of sediment 3.4 The free-living type of water area Surface water area of 3.5 adnate sediment type Body usually light green to brown. Body flat, the head is very wide and flat. The outside of the general ciliate upper jaw to be the end of a brush-like hair, the surface of the lower lip should also brush with thick hair. Type before and after the joint was full, it can only move forward and backward. The wide and flat foot leg section, tibia tarsus slender, its posterior surface and often densely hairy. Lateral abdominal gills. The back side of the leaf-like gills, fleshy; ventral side of gill filaments normally located in the back of the body, stretched out from the base of leaf-shaped gills. The leafy part of the gill-like suction cups to each other using the combination is conducive to absorption in the substrate surface. Some types 1 and 7 gill extends to the ventral body side, about two or close contact with gill contact with each other, so that the gills of the abdomen to form a suction cup-like structure of the whole (Figure 3.5). Wire on the tail are generally more sparse hair section between Central was born. Dark nature. Scraping the surface of the algae eating the food rocks. Able to swim, swimming, splashing into the water mainly by the gills. State of life can see the gills shook. Mayfly families on behalf of the flat type, which is a flat wasp (Heptagenia), Gao Xiang wasp genus (Epeorus), River chin wasp genus (Rhithrogena) the most typical. Water area of 3.6 dwelling type substrate gap This environment there are two types of mayflies. A class of aquatic plants living in water areas and litter in a class of living in a crack in the rocks. Gap in living in the river stones flower wasp families (Potamanthidae) as the representative of the types (Bae & McCafferty 1994). The general body of such ephemera flat, is light yellow to reddish brown. Palate with a distinct upper teeth, upper teeth and hair, often with teeth. Foot section of each leg is relatively wide and flat, while the tibia is slender cylindrical tarsus. Before the hind tibia and tarsus of the back side of the inner edge of dense hair. Lateral abdominal gills, 1 gill degeneration, and 2 to 7 and the mayfly gill shape very similar to the total subjects, but at the side of the body. Back surface of the abdomen with a variety of markings. The end of the base and end silk smooth, but with fine hairs on both sides of the middle. Swimming power stronger, filter-feeding. Above classification is not strict. Living environment for each type of ephemera, nor immutable. One type of water areas often were found in still water, but water still water area types in the area is very difficult to find. Overall, the choice of each habitat type still strict, when collected in each habitat, and its representatives are often the highest detection probability. 4 understand the form and related mayfly nymphs significance of habitat Compared with adults, mayfly larvae show greater morphological diversity. The classification and identification of a variety of forms to provide a very useful material. Little change in some types of adult forms, such as the four mayfly families, small mayfly families, small mayfly mayfly Section and Branch River flowers, different larval species comparison of the types of identification is often very effective. By representatives of each habitat type morphology of understanding, according to external morphology ephemera, it can generally infer the living environment and feeding habits. A variety of mayflies have relatively strict habitat _select_ion, in the acquisition process in order to improve collection efficiency, it should be as much as possible in different aquatic environments to collect a small sample. At the same time, it should address the activities of all kinds of ephemera with different ability to take a different collection methods and techniques. For those who live concealed and the type of activity is not strong, in the process of collecting samples, have enough patience and time to wait for them to come out from the shelter. While the type of activity is very strong, often difficult to easily adopt the need to _select_ the trawl or cages and other necessary specialized tools and the relative number of the collection. Mayfly nymphs because there is diversity in form, can infer the existence of certain mayfly nymphs plasticity, that is, under the action of natural _select_ion, different from the same branch of the ancestral larval form may be some diversity, such as small mayfly Section nymphs have three main forms: a long-haired type forefoot, monocular thorns and Normal. If the number of ancestors from different branches choose the same living environment, they may be on the external morphology showed a high degree of consistency or convergence. Therefore, in the reconstruction of phylogenetic relationships, larval feature _select_ion should be very careful. As different mayfly species and their morphology and their small environment and aquatic life are closely related to living habits, therefore, mayfly nymphs in the water quality monitoring has been widely used. Graphic Branch of China keys Ephemeroptera (Insecta: Ephemeroptera) http://202.119.109.14/dwx/fuyou_news/index_4.htm Mayfly species have been reported in China http://202.119.109.14/dwx/fuyou_news/index_1_3.htm
Schistonota