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1.
The morphology of the coxa and trochanter was studied in 205 species from 68 fly families to compare these structures with respect to ability to fly in a streamlined posture, with the middle legs pointing forward and pressed to the thorax. Only Brachycera are able to attain this posture. The forward turn of the coxa at this position is hindered by the junction of the coxa with the pleuron. Recovery of mobility is gained in two ways. (1) By reduction of the contact zone between coxa and pleurite, as in Asiloidea, Bombyloidea, and Empidoidea. Within these flies, the streamlined posture was recorded in Bombyliidae and in a robber-fly, Laphria flava . Others fly with their middle legs straddled laterally or trailing backwards. (2) Longitudinal splitting of the coxa into three coxites provides intracoxal mobility in most Tabanoidea and Cyclorrhapha. The hind and medial coxites rotate about the front coxite and change the coxo-trochanteral axis, thus compensating for restricted protraction. Separation of the hind coxite appears in primitive Tabanoidea, and a separate middle coxite was found in several families among the Nematocera. The streamlined posture was recorded in horse-flies, stratiomyids, and in many Cyclorrhapha except Micropezidae and Hippoboscidae. There is morphological evidence for a possible secondary fusion of coxites at least in Dolichopodidae and Opetidae as well as for the origin of Cyclorrhapha from a miniature ancestor.  相似文献   

2.
The middle coxa in Calliphora consists of three sclerites. Two rear sclerites are able to rotate relative to the front sclerite about the intracoxal axis (ICA). The turn ahead about ICA puts the leg in a peculiar position with minimal aerodynamic resistance. Sclerites are articulated in a form of complex kinematic chain. Distances between articulations were measured; using them, various configurations of the model coxa were obtained by geometrical synthesis, the turn about ICA was simulated, and the muscle driving the turn ahead was revealed (the hind elevator). The middle leg with the complex coxa in most of Brachycera is specialised for the advanced flight performance.  相似文献   

3.
In Auchenorrhyncha, jumping is achieved by metathoracic muscles which are inserted into the trochanter of the hind leg. The synchronisation of movements of the hind legs is a difficult problem, as the leg extension that produces the jump occurs in less than 1 ms. Even slight asynchrony could potentially result in failure of a jump. Both the synchronisation of the movements of a pair of jumping legs, and their stabilisation during a jump, seem to be important problems for small jumping insects. The present study was performed in order to clarify some questions of the functional morphology of the leafhopper jumping mechanism. It is based on skeleton-muscle reconstruction, high-speed video recordings, transmission (TEM) and scanning electron microscopic (SEM) investigations of the cuticle, together with 3D inverse-kinematic modelling of angles and working zones of hind leg joints of cicada Cercopis vulnerata (Cercopidae). The complete extension of the hind leg takes less than 1 ms, which suggests that the jump is powered not only by the muscle system, but also by an elastic spring. Histological staining and fluorescence microscopy showed resilin-bearing structures, responsible for elastic energy storage, in the pleural area of the metathorax. Synchronisation of hind leg movements may be aided by microtrichia fields that are located on the medial surface of each hind coxa. In Auchenorrhyncha, hind coxae are rounded in their anterior and lateral parts, whereas medial parts are planar, and contact each other over a rather large area. The inverse-kinematic model of propulsive leg movements was used to draw the surface outlined by the medial surface of the coxa, during the jump movement. This is a cone surface, faced with its bulged-in side, medially. Surfaces outlined by the movements of both right and left coxae overlap in their anterior and posterior positions. In both extreme positions, coxae are presumably connected to each other by coupled microtrichia fields. Thus, in extreme positions, both coxae can be moved synchronously.  相似文献   

4.
37 states of 9 characters of the thoracic combs, coxae, and the 5th hind tarsomere of fleas are analyzed. Some of these character states mark groups of families in the infraorders Pulicomorpha, Hystrichopsyllomorpha, Pygiopsyllomorpha and Ceratophyllomorpha.  相似文献   

5.
Summary Rows of long, smooth hair sensilla situated on both sides of the leg coxae were examined in the spider Cupiennius salei (Ctenidae). The hair shafts point into the space between adjacent legs and are deflected when the hairs of one coxa touch the cuticle of the neighboring coxa. 1. Unlike the serrated hair shafts of the ubiquitous tactile and chemosensitive setae of spiders, these hairs are entirely smooth. At their base they are articulated in a socket with an asymmetrical groove that determines the direction of hair deflection. Hair shafts are up to 1000 m long. The exact grouping of smooth hairs in rows is typical of the coxae for each pair of legs. 2. Unlike the other, multiply innervated cuticular sensilla of spiders, smooth hairs are supplied by only a single mechanosensitive neuron. This is confirmed by electrophysiological recordings from single hairs. Threshold deflection to elicit a spike response lies near 1°. The response to maintained, step-like stimuli declines rapidly. 3. All central endings of these hair receptors in the fused segmental ganglia are confined to dorsal neuropil of the ipsilateral neuromere. The specific arborization pattern resembles an elongated, three-pronged fork with a long central prong. Topography, natural stimulus situation, and the phasic response characteristic of smooth hairs suggest that spiders use these sensilla to monitor the relative distance between leg coxae during locomotion.  相似文献   

6.
记述革板螨属3新种和派伦螨属1新种:井冈山革板螨Gamasholaspis jinggangshanensis sp.nov.,何氏革板螨Gamasholaspis hochyicheni sp.nov.,新阿革板螨Gamasholaspis novakimotoi sp.nov.和沙县派伦螨Parholaspulus shaxianensis sp.nov.  相似文献   

7.
Populations of Phlebotomus major were examined in two endemic and nonendemic foci of visceral leishmaniasis in Iran. Based on the shape of the aedeagus and ventrally located hairs of coxite and pharyngeal armatures, two morphotypes were found sympatrically in the endemic area of Borazjan. Significant differences in morphometric survey were observed in at least 11 measured characters. The aedeagus of the non‐endemic Miyandoab morphotype, and also of a few specimens from Borazjan, is completely parallel throughout its length with a slightly expanded end. Ventrally located hairs of the middle coxite were longer and more compact. It is close morphologically to P. major neglectus (P. neglectus), which was recently recorded from Iran. It is also morphologically similar to P. notus, which has not yet been reported from Iran and needs further investigation. The aedeagus of the morphotype occurring only in Borazjan is narrower in the middle and the hairs are closer to the base of the coxite and are shorter and more outspread, which makes it similar to P. major krimensis or P. neglectus. The two morphotypes occurring sympatrically in Borazjan do not appear to be subspecies and it may be premature to propose them as separate species. Further investigation is needed to clarify the actual status of P. major s. l. in Iran.  相似文献   

8.
钩瓣叶蜂属隶属于叶蜂科,已知230余种,中国已经报道77种.记述中国钩瓣叶蜂属1新种:尖唇钩瓣叶蜂Macrophya acuminiclypeus sp.nov.,该种与女贞钩瓣叶蜂 M.ligustri Wei et Huang,1997近似,但唇基缺口深,侧角狭长,端部尖,头部额区和中胸侧板刻点粗密,中胸背板前叶中沟模糊,几乎消失,后足股节基部1/4黄白色,锯腹片22刃,中部锯刃具10~11个后位亚基齿等,差别明显,易于鉴别.正模♀,江西萍乡芦溪,2004-04-03,魏美才采;副模:1♀,湖南浏阳,1985-05-08,童新旺,1♀,福建武夷山,1 100 m,2004-05-20,周虎.新种模式标本保存于中南林业科技大学昆虫模式标本室.  相似文献   

9.
The ozopores of cosmetid harvestmen rest upon lateral projections of the carapace, have simple or highly reduced channels, and are partially obscured by enlarged dorsal processes associated with coxae I and II. Rather than use scent gland secretions to form a chemical shield on the dorsum, the cosmetid harvestman exhibits a unique defensive behavior known as “leg dabbing” in which the distal tip of tarsus I or II is dipped into fluid that accumulate at the base of coxa II and the droplet on the tarsus is pointed toward the predator. Relatively little is known about interspecific variation in ozopore morphology among cosmetid harvestmen. In this study, we used scanning electron microscopy to examine the ozopores of males and females of nine species as well as those of antepenultimate nymphs for two species. Among adults, we found differences between species in the shapes of the ozopores (round or subtriangular), the morphology of the dorsal and lateral channels (if present), and the relative size, shape and armature of the dorsal posterior process (dpp) of coxa I and the dorsal anterior process (dap) of coxa II. Our observations suggest that the morphology of dpp I and dap II could be sources for systematic characters in future phylogenetic studies of the Cosmetidae. We observed ontogenetic differences but relatively little intersexual variation in the morphology of the ozopore. The ozopores of nymphs are generally more oval than those of adults and the opening of the ozopore of the nymph is less obstructed, if at all, by the dorsal coxal processes of legs I–II. These morphological differences suggest that nymphs may use scent gland secretions in a manner different from that of adults.  相似文献   

10.
A case of tick bite was found in the inguinal region of a 74-year-old Korean woman. She was attacked by the tick while working in her vegetable garden in the vicinity of mountain located in Suncheon City, the southern coastal area of the Korean Peninsula. On admission she complained of mild discomfort and itching around the bite area. The causative tick was 23 mm long and had slender pedipalps. The scutum was quite ornate and had eyes at the edge. The genital aperture was located anterior to the level of the coxa II. The spiracular plate was comma-shaped and the anus was surrounded posteriorly by the anal groove. The coxa I had subequal 2 spurs; the external one slightly larger. The spur of coxa IV was slightly longer than those of coxae II and III. The tarsus IV had 2 distinct subapical ventral spurs. It was identified as the fully engorged adult female of Amblyomma testudinarium. This is the first human case of Amblyomma bite in Korea.  相似文献   

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