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A new genus with a new species of Saldidae, Brevrimatus pulchalifergen. et sp. n., is described and illustrated. The fossil specimen was found from the Early Cretaceous Yixian Formation of Duolun County, Inner Mongolia, China. Phylogenetic analyses within Saldidae were performed, and the results indicate Brevrimatus pulchalifergen. et sp. n. should be assigned to the subfamily Chiloxanthinae. 相似文献
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This study describes morphological changes in the male reproductive system of Miroculis amazonicus (Savage & Peters) from mature nymphs to subimago stages. The sperm ultrastructure of Massartela brieni (Lestage), Farrodes carioca (Domínguez et al) and Miroculis mourei (Savage & Peters), as well as aspects of cell fragments observed in these species' subimagos deferent ducts were described. Sperm from the three species studied are aflagellated and immotile, while those from F. carioca and Ma. brieni are approximately spherical with a homogenous nucleus and acrosome. Sperm of F. carioca present two or three mitochondria located between the nucleus and the acrosome. In Ma. brieni, only one lateral mitochondria was found. Sperm from Mi. mourei are shaped as a number 'eight', with electron lucent spots inside the nucleus and two mitochondria above the acrosome. Large cell fragments containing degenerative vesicles and some sperm were observed in the deferent duct lumen of the three species. Testes of Mi. amazonicus are extremely reduced in the subimago stage, which suggests that these cell fragments originated from testes degeneration. 相似文献
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The anatomy and histology of the abdominal eversible vesicles and the male reproductive tract of the spoonwing lacewing Palmipenna (Neuroptera: Nemopteridae) have been examined. The eversible vesicles open as a pair of large bulbous sacs between tergites five and six, each folding into halves during retraction. They consist of highly pleated cuticle, beneath which are typical gland cells, each having a circular or oval end apparatus surrounded by closely packed microvilli. These communicate to the surface via cuticularized channels. In spite of considerable behavioral observations, male Palmipenna were never noted with everted vesicles. Even during mating trials, where females were presented to males in the field, the vesicles were never everted during the attempted copulation that ensued. Our observations indicate that mate attraction is mediated by the release of a female pheromone. The function of the eversible vesicles and their associated gland cells remains unknown, and their structure appears to be unique to the Nemopteridae. The reproductive tract is similar to that of other Neuroptera, consisting of a pair of five-lobed testes, a medium-to-large pair of seminal vesicles, and three pairs of accessory glands. The major accessory glands are surrounded by circular and longitudinal muscle, and are lined by an epithelium, the cells of which presumably secrete the amorphous rods of material always present in this pair of glands. The sperm in the seminal vesicles are elongate, with a pointed head and a 9 + 9 + 2 configuration in the flagellum. A single spermatophore, similar in shape to that described for other Neuroptera, was found occluding the bursa copulatrix of a teneral female. © 1994 Wiley-Liss, Inc. 相似文献
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R. A. Patzner 《Journal of fish biology》1991,39(6):867-872
The testis, the seminal vesicles and the spermatic duct of Coralliozetus angelica (Böhlke & Mead) are described. The testis and the seminal vesicles are not arranged in pairs but are single. The testis is situated on the left side of the animal and consists of chambers instead of tubules. The seminal vesicle on the right side is composed of two different types (seminal vesicle 1 and 2) which are not connected with each other 相似文献
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Karl Meßlinger 《Zoomorphology》1987,107(1):49-57
Summary The fine structure of trichobothria in the scorpions Buthus occitanus (Amoureux, 1789) and Euscorpius carpathicus (Linné, 1767) was investigated by electron microscopy. In both species, cuticular and cellular characteristics are very similar. The articulation of the hair corresponds to that of other arachnid hair sensilla. The receptor endings are excentrically attached to the hair base. They consist of an enveloped S-shaped bundle of seven dendrites in B. occitanus and four in E. carpathicus. Neighbouring outer dendritic segments differ a great deal in diameter and ciliary modification. In B. occitanus, three enveloping cells and several additional secretory cells surround the inner dendritic segments. Structural characteristics are compared to those of other arachnid sensilla and their possible functional significance is discussed. 相似文献
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The male genitalia of the rock hyrax (Procavia and Heterohyrax) are described. Features of the gross anatomy and histology of the testes and male accessory organs are presented, and comparison is made between the sexually active and sexually quiescent animal.
Microscopical observations have revealed the main area of storage of spermatozoa in this mammal and partly on these grounds, a new nomenclature for different parts of the reproductive system is proposed. Seasonal variations in male sexual activity in these mammals are also discussed, in addition to anatomical considerations. 相似文献
Microscopical observations have revealed the main area of storage of spermatozoa in this mammal and partly on these grounds, a new nomenclature for different parts of the reproductive system is proposed. Seasonal variations in male sexual activity in these mammals are also discussed, in addition to anatomical considerations. 相似文献
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Nemerteans possess serially arranged gonads that lie between the midgut pouches. In both sexes the gonads are lined with an epithelium. During maturity, they gain contact to the exterior by a ciliated duct, which is generally assumed to be a derivative of the gonad. Gonad lining and sperm ultrastructure are little known in heteronemerteans, a group of nemerteans belonging to the Anopla, one of the two large nemertean subgroups. Reproduction biology in heteronemertean Lineus viridis allows predicting a modified sperm type, so-called introsperm for this taxon. Nothing is known on the fate of the testes at the end of the reproductive period of this perennial species. In order to test the predictions and to broaden the data base, males of L. viridis were collected at different times of the year. Histological and ultrastructural data show that the gonad wall is lined with different aciliated endothelial cells and germ cells, while the gonoduct is formed by densely ciliated cells. The testes are completely filled with sperm cells during maturity; there is no hint at ongoing spermiogenesis at this time. The sperm consists of head, midpiece and tail. Externally, head and midpiece cannot be discriminated. The acrosome is cup-shaped and lies anterior to the nucleus which contains 6–8 lateral ridges. Three long mitochondria mark the midpiece. They line the posterior section of the nucleus and extend up to the level of the ciliary basal structures. The sperm morphology corroborates the predictions derived from the mode of reproduction. At the end of the reproductive period the male gonads change cellular composition, while the gonoduct degenerates. Provided that both sexes show the same growth rate, male offspring acquire sexual maturity earlier than female offspring, since L. viridis males are always smaller than the females. In contrast to the males, females keep their gonads and gonoducts during most time of the year. Since large males were never found within the studied population, these data indicate that L. viridis might be a consecutive hermaphrodite. 相似文献
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Allan F. Wolfe 《Journal of morphology》1971,135(1):51-69
The male reproductive system of Artemia was studied by routine histological and histochemical techniques to demonstrate the general histology and distribution of proteins, carbohydrates, lipids, and alkaline and acid phosphatases. The System Consists Of Paired Testes, Vasa Deferentia, Accessory Glands, And Penes. The Testes Contain Germ Cells And Supporting Cells Throughout Their Entire Length. The Former Cells Are Located In Clusters And Undergo A Spermatogenic Maturation Which Is Similar To That Described For OtherAnimals. The Supporting Cells Seem Implicated In The Nourishment Of The Germ Cells. The Vas Deferens, Which Consists Of Secretory Epithelium Surrounded By Circular And Longitudinal Muscles, Secretes The Seminal Fluid, Containing A Neutral Mucopolysaccharide Or Mucoprotein, And Stores The Mature Sperm. The Accessory Gland Consists Of Approximately 20 Pairs Of Gland Cells, Each Pair Drained By A Neck Cell And Duct Cell Into The Collecting Duct. The Glandular Secretion, Mainly A Neutral Mucopolysaccharide Or Mucoprotein, Might Function As A Lubricant, A Copulatory Plug, Or An “Activator Substance” For The Sperm Or For Fertilization. Each Penis Consists Of A Non-Eversible Part And An Eversible Part Which Is A Tortuous Muscular Tube That Connects The Vas Deferens To The Outside. 相似文献
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External morphological features of adult males are described in the stick insect Hermarchus leytensis from the Philippines, a species belonging to the little-known euphasmatodean lineage Stephanacridini. Mouthparts are characterized by some likely specialized features: (1) a dentate dorsal cutting edge on the mandibles; (2) distinct differences in size and shape between the galeae; (3) absence of an apical field of trichomes on the galeae; and (4) lacinial setae not protruding from the mesal margin, which features three bearing-like protuberances. The latter character state represents a very unusual condition, not known in other phasmatodeans or even in polyneopteran insects. A distinctive characteristic of attachment devices is that each euplantula is divided into two separated pads with a smooth microstructure, as it also occurs in some members of the clade Schizodecema. Male terminalia exhibit character states previously unknown in Stephanacridini, including (1) a symmetrical type of vomer and (2) claspers equipped with ∼70 very minute ventral teeth on each thorn pad. Potential implications for the systematic placement of H. leytensis are discussed. The results also underline the importance of microanatomical investigations as source of substantial characters for future analyses on phasmatodean systematics. 相似文献
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J. A. Lis C. W. Schaefer 《Journal of Zoological Systematics and Evolutionary Research》2005,43(4):277-283
Tibial combs in representatives of the family Cydnidae are described in detail for the first time. The structure was studied in 98 species of 58 genera representing all the subfamilies, among them 16 species were investigated using scanning electron microscopic (SEM) techniques. In addition, Parastrachia japonensis (Scott, 1880) of the family Parastrachiidae, and two species of Dismegistus Amyot and Serville, 1843 (a genus of uncertain systematic position within Pentatomoidea) have also been studied. Morphological terminology is proposed for all the structures connected with tibial combs and the term 'the tibial comb complex' is suggested; its functional, taxonomic and phylogenetic significance is also discussed. The genera of Cydnidae can be classified into two groups depending on differences in the tibial comb complex, when it is present; moreover, its absence in the tribe Scaptocorini (Cephalocteinae) is demonstrated for the first time and is regarded as an autapomorphy of this tribe. Data on the occurrence of tibial combs in other families of true bugs (Hemiptera: Heteroptera) are also briefly reviewed, and an anagenetic trend in their evolution in terrestrial Heteroptera is hypothesized. The presence of tibial combs on all legs is regarded as the most plesiomorphic state. 相似文献
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The reproductive system of the important basal gastrotrich Neodasys chaetonotoideus is described and reconstructed on the basis of light microscopy, serial ultrathin sections (ultrastructure) and scanning electron microscopy. Starting frontally, the hermaphroditic reproductive system consists of paired and tube shaped lateral testes that do not possess elongated seminal ducts but most likely open directly via paired ventral pores. The unpaired, medio‐dorsal ovary region contains early oogenic stages that mature caudally towards the uterus region, where the most mature egg is positioned laterally to the midgut. The ovary region is not covered with an epithelial lining whereas the uterus region possesses a distinct epithelial wall. Between ovary and uterus region, we have detected a conspicuous section of the female gonad, the vitellogenic oviduct that consists of a thick epithelial wall which forms cellular protuberances into the developing oocytes passing the oviduct. We interpret this as a special, hitherto undescribed mode of vitellogenesis in Gastrotricha. Further caudally, the uterus continues with the fronto‐caudal organ, a complex of two substructures that are apparently homologous to the frontal organ and the caudal organ of many species of the Gastrotricha Macrodasyida. Neodasys chaetonotoideus obviously engages in spermatophore formation and transfer. In this study we develop a morpho‐functional scenario for the gonads and accessory organs in terms of spermatophore production, exchange and oviposition. We compare our newly obtained data with already published results on the reproductive organs of several species of Gastrotricha by means of a species‐character matrix and provide a computer aided evaluation by a parsimonious character optimization. A reconstruction of the reproductive system of the stem species of Gastrotricha on the basis of three recent phylogenetic analyses is presented. These reconstructions give support for a Neodasys‐like reproductive system in the ground pattern of Gastrotricha with slight morphological differences and direct transfer of spermatozoa rather than spermatophore transfer. The evolution of selected characters is traced thus revealing some incidents of convergent evolution as well as the evolutionary replacement of the ancestral frontal organ by the derived frontal sac in at least two separated lineages. 相似文献
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The karyotype and male meiosis, with a particular focus on the presence or absence of chiasmata between the homologs, were studied in the water boatman species Cymatia
rogenhoferi (Fieber) and Cymatia
coleoptrata (Fabricius) (Corixidae, Cymatiainae). It is shown that the species have 2n = 33 (28A+2m+X1X2Y) and 2n = 24 (20A+2m+XY) respectively, post-reduction of sex chromosomes, and achiasmate meiosis of an alignment type in males. Cytogenetic and some morphological diagnostic characters separating Cymatia Flor from the rest of Corixidae are discussed. 相似文献
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The ciliated epidermis of Xenoturbella bocki (Platyhelminthes, Xenoturbellida) with some phylogenetic considerations 总被引:1,自引:0,他引:1
The epidermis of Xenoturbella bocki Westblad was studied by scanning and transmission electron microscopy. Two cell types predominate in the epidermis: multiciliated epidermal cells and non-ciliated or monociliated gland cells. A conspicuous feature is the dense ciliary coverage and the numerous gland cell openings. Xenoturbella has a characteristic pattern of axonemal filament termination in the distal tips of their cilia. Each epidermal cilium has the typical 9 + 2 patten through the major part of its shaft. Near the tip there is a shelf at which doublets 4–7 terminate. Doublets 1, 2, 3, 8 and 9 continue into the thinner distal part of the cilium. A similar shelf in cilia is known only from the turbellarian orders Nemertodermatida and Acoela, and hence may be an apomorphic feature which indicates a close relationship between Xenoturbellida, Nemertoder-matida and Acoela. The basal body is provided with a so-called basal foot which has a cross-striated appearance and an expanded distal plate that seems to act as a microtubule organizing center. Approximately 15–25 microtubuli radiate from the endplate of the basal foot to the basal bodies caudally. The arrangement of basal foot and ciliary rootlets in Xenoturbella differs from that of Acoela and related orders in that there are two striated rootlets only (an anterior and a posterior one), rather than one main rootlet and two lateral rootlets. 相似文献
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Male rats treated chronically with high doses of Valium (50mg/ Kg/day; 10 days) failed to exhibit changes in their reproductive system. Testicular and prostate weights, serum testosterone (T) and LH were unaffected. Testes and pituitary tissue stimulated with LH and GnRH, respectively, released normal amounts of T, LH and FSH. Brain benzodiazepine receptors were slightly but significantly elevated by Valium treatment as well as by castration. We conclude that the male reproductive system is resistant to chronic Valium treatment even though the brain levels of benzodiazepine receptors are not. 相似文献
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Fine structure of the male reproductive system in two species ofHaplognathia sterrer (Gnathostomulida,Filospermoidea) 总被引:1,自引:1,他引:1
Summary The structure of the male reproductive systems of two species ofHaplognathia cf.lyra andH. cf.rosacea was described. The structure of the testes and the anterior portions of the sperm ducts in both species was found to be similar. However, considerable species differences were found between the structures of the glands and muscles associated with the reproductive systems. These were more elaborate inH. cf.lyra than inH. cf.rosacea. The former species possessed an H-shaped sperm duct gland, three distinct groups of penis muscles and a penis with two cell types and with a lumen. The latter species had paired sperm duct glands, no specialized penis muscles and a penis with only one cell type and without a detectable lumen. No open gonopore was observed in either species. The sperm presumably exit through a ventral tissue connection observed connecting the penis and the ventral epidermis. These findings were discussed in the light of Mainitz's (1977) theory concerning the primitive penis type within the Gnathostomulida.Abbreviations ap
anterior-posterior penis muscles
- bm
basement membrane
- csd
common sperm duct
- dl
dorsal lumen of the penis
- dp
dorsal gland cells of the penis
- dv
dorsoventral muscles anterior to the penis
- dw
sperm duct wall cell
- e
epidermis
- ex
exit cell
- g
intestine
- gl
gut lumen
- n
nerve
- p
penis
- sd
sperm duct
- sdg
sperm duct gland
- tw
testes wall cell
- vl
ventral lumen of the penis
- vp
ventral gland cells of the penis
This project was supported by NSF grant #GB 42211 (R.M. Rieger P.I.). The line drawings have been executed after our design by Ms. Linda McVay 相似文献