Trueman, J.W.H. (1990), Comment: evolution of insect wings: a limb exite plus endite model. Canadian Journal of Zoology.
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The shaft of R. consimilis only have simple endite on podomere 3. Frontal appendages of R. consimilis had been misidentified as Anomalocaris saron due their similar overall appearance.
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But the second maxilliped has segments arranged in usual serial manner; bearing exopod; endopod 4-segmented. Mandible usually with incisor and molar processes and palp. Second maxilla with palp; endite well developed.
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Eyes are elongate, reaching nearly to distal end of antennular peduncle. Their first pair of pereiopods is robust and similar in size to the second pair; distinctly chelate. The second pair of pereiopods is divided into four articles. The first maxilliped has an exopod far removed from the endite.
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Embrouded was he, as it were a meede, Al ful of fresshe floures, whyte and reede; Syngynge he was, or floytynge, al the day, He was as fressh as is the monthe of May. Short was his gowne, with sleves longe and wyde. Wel koude he sitte on hors, and faire ryde. He koude songes make, and wel endite, Juste, and eek daunce, and weel purtreye and write.
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A sharp spine is placed on the outer margin of the antennal peduncle near the base of the scaphocerite. The mandible bears no palp; the incisor process ends in three or four teeth, the outer of which are the larger; the molarprocess bears some rounded teeth distally. The maxillula has the two laciniae reasonably slender, the palp is deeply bilobed. The maxilla bears a single endite which is cleft.
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The frontal appendages of hurdiids have a distinctive morphology, with the appendage of most species bearing five equally-sized elongate blade-like ventral spines known as endites. Subsequent podomeres were reduced in size and with only small endites or none. Each podomere bore only a single endite, unlike other radiodonts, in which the endites were paired. In most species, the endites were curved medially, so that the appendages formed a basket-like structure.
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Brevisomabathynella cooperi is a species of crustacean. It was first found in Western Australia. It stands out within its family by its pygmoid body and its long head. At the same time, its mouthparts show: a very large labrum with a great number (over 30) of teeth; its incisor process with four main teeth and three very small other teeth, arranged in two groups; and the distal-inner spines of the farthermost endite of its maxillule being longer than its terminal spines.
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Brevisomabathynella cunyuensis is a species of crustacean. It was first found in Western Australia. It stands out within its family by its pygmoid body and its long head. At the same time, its mouthparts show: a very large labrum with a great number (over 30) of teeth; its incisor process with four main teeth and three very small other teeth, arranged in two groups; and the distal-inner spines of the farthermost endite of its maxillule being longer than its terminal spines.
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Cylindroleberididae is a family of ostracods that shows remarkable morphological diversity. The defining feature is the possession of gills: 7–8 leaf-like pairs at the posterior of the body. Other features common to all species in the family include a "baleen-comb" on both the maxilla and the fifth limb, a sword-shaped coxal endite on the mandible, and the triaenid bristles on the basal endites of the mandible. Species of the Cylindroleberididae are found in marine areas, from shallow waters to depths of more than .
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The challenge to the status has focused on Agnostina partly due to the juveniles of one genus have been found with legs differing dramatically from those of adult trilobites,Müller, K. J. & Walossek, D. (1987): "Morphology, ontogeny, and life habit of Agnostus pisiformis from the Upper Cambrian of Sweden". Fossils and Strata, 19, 1-124. suggesting they are not members of the lamellipedian clade, of which trilobites are a part. Instead, the limbs of agnostids closely resemble those of stem group crustaceans, although they lack the proximal endite, which defines that group.
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According to more current literature, gill-like structures and the paranotal lobe still appear to be among the most important ancestral structures to insect wing origins. Today, there are three main theories on the origins of insect flight. These theories are referred to as the paranotal lobe theory, the gill theory and the dual theory of insect wing evolution. These theories postulate that wings either developed from paranotal lobes, extensions of the thoracic terga; that they are modifications of movable abdominal gills as found on aquatic naiads of mayflies; or that insect wings arose from the fusion of pre-existing endite and exite structures each with pre-existing articulation and tracheation.
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The hypothesis with perhaps the strongest evidence is that which stems from the adaptation of endites and exites, appendages on the respective inner and outer aspects of the primitive arthropod limb. This was advanced by Trueman based on a study by Goldschmidt in 1945 on Drosophila melanogaster, in which a pod variation displayed a mutation transforming normal wings to what was interpreted as a triple-jointed leg arrangement with some additional appendages but lacking the tarsus, where the wing's costal surface normally would be. This mutation was reinterpreted as strong evidence for a dorsal exite and endite fusion, rather than a leg, with the appendages fitting in much better with this hypothesis. The innervation, articulation and musculature required for the evolution of wings are already present in the limb segments (podomeres).
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Gower's previous works had been written in Anglo-Norman French and Latin. It is not certain why he chose to write his third long poem in English; the only reason Gower himself gives is that "fewe men endite In oure englyssh" (prol.22-23). It has been suggested that it was the influence of Chaucer, who had in part dedicated his Troilus and Criseyde to Gower, that persuaded him that the vernacular was a suitable language for poetry, and the influence of Chaucer's Legend of Good Women has been detected in the Confessio (Macaulay 1908:sec 23). With the exception of a 74line letter "unto cupid and to venus" in Book VIII, Gower did not adopt the new pentameter with which Chaucer had recently been experimenting, and which was in the 15th century to become the standard metre for English rhyme.
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Female Aptostichus simus female anatomy from a standard light microscopy views of female an Aptostichus simus specimen (MY3432). 31 side view 32 ventral view, sternum 33 dorsal view, carapace 34–35 eye group, dorsal and lateral views 36 leg I prolateral view 37 leg IV retrolateral view 38 palpal endite Aptostichus simus male anatomy from Chamberlin, 1917 male specimens from San Diego County; scale bars = 1.0mm. 274 habitus (AP1209) 275–278 secondary sexual characteristics (AP819) 275 retrolateral aspect, leg I 276 prolateral aspect, leg I 277 ventral view, pedipalp bulb 278 retrolateral aspect, pedipalp 279, 280 line drawings, leg I articles 279 retrolateral and prolateral aspect of specimen from San Diego County, Imperial Beach 280 retrolateral aspect, tibia and patella, in descending from San Diego County, Imperial Beach and Santa Barbara County, Carpinteria State Beach Aptostichus simus is a species of trapdoor spider in the family Euctenizidae. It is a medium-sized mygalomorphCommon Spiders of North America Page 114 found in the United States and Mexico.
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