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Journal ArticleDOI

The glandular units of the spermathecae of machilids (Microcoryphia): ultrastructure and modifications during moulting

01 Jan 1989-International Journal of Insect Morphology & Embryology (Pergamon)-Vol. 18, pp 97-110
TL;DR: The spermathecae of 4 species of Microcoryphia present characteristics related to the primitive phylogenetic position of these apterygote insects, including paired organs situated in the 8th abdominal segment on each side of the rudimentary genital chamber.
Abstract: The spermathecae of 4 species of Microcoryphia (Lepismachilis targionii, Trigoniophthalmus alternatus, Machilis sp. and Machilinus rupestris) present characteristics related to the primitive phylogenetic position of these apterygote insects. They are paired organs situated in the 8th abdominal segment on each side of the rudimentary genital chamber. Each spermatheca includes 2 different tissues: (a) a simple epithelium surrounding 2 spermathecal capsules and communicating with the genital chamber by short ducts; (b) a complex glandular tissue composed of numerous functional units, each made up of several cell types — a large glandular cell with a subapical reservoir, 2 basal cells, a ductule cell and enveloping cells. One of the basal cells, called the ciliary cell, presents a dendrite-like process containing 2 apical centrioles in alignment. Several ductules of neighbouring units join together before opening in the genital chamber, independently of the ducts of the spermathecal capsules. The spermathecae undergo marked changes during moulting periods. Apolysis is followed by a partial dedifferentiation of the glandular cells, then the formation of new ductule cavities and the growth of a pseudocilium at the apex of the dendrite-like process of each ciliary cell. Afterwards, cuticular material is laid down around the pseudocilia, forming the intima of the new ductules, which results from the secretions of at least the ciliary and ductule cells. The pseudocilia degenerate before ecdysis. A comparison is made with the organogenesis of analogous organs described in different insect species.
Citations
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Journal ArticleDOI
01 Apr 2017-Zoology
TL;DR: This review examines several aspects of and gaps in the current understanding of spermatheca biology, including morphology, function, reservoir filling, development, and biochemistry.

72 citations

Journal ArticleDOI
TL;DR: A volatile sex pheromone is produced in an adult female-specific gland located on the anterior of the last abdominal tergite of the female German cockroach, Blattella germanica (L.).
Abstract: A volatile sex pheromone is produced in an adult female-specific gland located on the anterior of the last abdominal tergite of the female German cockroach, Blattella germanica (L.). In this area, the cuticle forms deep depressions in which a large number of cuticular orifices are located. The cuticular orifices are connected to secretory cells via cuticular ducts surrounded by duct cells. The pheromone gland exhibits a clear developmental maturation in relation to sexual maturation of the female. The secretory cells of a newly formed gland in the imaginal female are small and contain few secretory vesicles. The amount of extractable pheromone in the gland is low on day-0 but it increases with age and peaks on day-6. The secretory cells in a mature day-6 gland are characterized by a large number of electron-lucid secretory vesicles. abundant RER and SER, a large nucleus and a long, convoluted end apparatus which is lined with numerous microvilli. The contents of the secretory vesicles are exocytosed into extracellular reservoirs at the base of microvilli and then transported to the cuticular surface through the long ducts. The supportive function of the duct cell in the glandular organization and developmental regulation of the gland are discussed.

35 citations

Journal ArticleDOI
TL;DR: The ultrastructure of the spermathecal epithelium of the African Migratory Locust Locusta migratoria migratorioides was investigated with the aid of transmission and scanning electron microscopic methods.
Abstract: The ultrastructure of the spermathecal epithelium of the African Migratory Locust Locusta migratoria migratorioides R. & F. (Orthoptera: Acrididae) was investigated with the aid of transmission and scanning electron microscopic methods. The unpaired spermatheca can be subdivided into a multiple coiled tube and a terminal bulb region with vestibule, small apical and extensive pre-apical diverticulum. The wall of the spermatheca consists of a chitin intima, a layer of epithelial cells with a distinct apical microvilli border and a layer of gland cells, whereby slender projections of the epithelial cells extend between the gland cells. Through extensive folding, the basal plasma membrane of the gland and epithelial cells form a huge labyrinth, which is bounded by a basal lamina. Extending into the above mentioned projections there are bundles of parallel-arrayed microtubules, which run perpendicular to the microvilli border of the epithelial cell. They end in the base region of the microvilli and in the basal labyrinth on hemidesmosomes and serve to provide a mechanically stressable anchorage for the epithelium. The gland cells show structures typical for the production of export proteins: ribosomes, rER, dictyosomes, as well as vesicles of different size and electron-density. Every gland cell contains an extracellular cavity, arising through invagination, which is coated with a microvilli border. Over an end-apparatus and a ductule joining onto it (also with chitin intima) the lumen of the extracellular cavity is connected with the spermathecal lumen. The release of secretions and other substances from the epithelium into the spermatheca lumen is as possible as the uptake of substances from the latter into the epithelium. Regional differences in the fine structure of the cuticular intima, epithelial and gland cells point to different functions of the epithelium in these regions.

30 citations

Journal ArticleDOI
TL;DR: Pholcus phalangioides does not possess receptacular seminis; it is considered to serve primarily as a matrix for sperm storage, i.e. to keep the spermatozoa in a fixed position.
Abstract: Pholcus phalangioidesdoes not possess receptacular seminis. The uterus externus (genital cavity) itself functions as a sperm storage structure. Two accessory glands are situated in the dorsal part of the uterus externus; they discharge their secretory product into the genital cavity. The secretion is considered to serve primarily as a matrix for sperm storage, i.e. to keep the spermatozoa in a fixed position. The accessory glands consist of numerous glandular units, each being composed of four cells: two secretory cells are always joined and surrounded twice by an inner and an outer envelope cell. Both envelope cells take part in forming a cuticular ductule that leads from the secretory cells to the pore plates of the uterus externus. The inner envelope cell produces the proximal part of the canal close to the microvilli of the secretory cells, whereas the outer envelope cell produces the distal part of the canal leading to the pore plate. Close to the pore the latter exhibits prominent microvilli that might indicate additional secretory activity.

29 citations

Journal ArticleDOI
TL;DR: The ultrastructure of integumentary glands of the adult ladybird, Semiadalia undecimnotata (Coleoptera : Coccinellidae) is described, which shows secretions are abundant and released on the surface of the cuticle in the shape of tortuous cylinders, which are resistant to acetone treatment.
Abstract: The ultrastructure of integumentary glands of the adult ladybird, Semiadalia undecimnotata (Coleoptera : Coccinellidae) is described. Two types of glands can be found distributed over the head, thorax, and abdomen: glands without ducts and glands with secretory ducts. Glands without ducts consist of a single cell and a secretory apparatus located within the thickness of the cuticle and equipped with a cuticular cribriform plate; this cribriform plate separates 2 superimposed cavities, and epicuticular filaments fill the lower cavity. Glands without ducts are thought to release volatile pheromones. Glands with a duct appear to be made of 2 kinds of cells: one cell forms the receiving duct and later synthesizes the secretory products, one (or more) cell makes the evacuating duct. Their secretions are abundant and released on the surface of the cuticle in the shape of tortuous cylinders, which are resistant to acetone treatment. Glands without ducts and glands with secretory ducts correspond, respectively, to classes 1 and 3 gland cells according to the nomenclature of Noirot and Quennedey (1974, Annu. Rev. Entomol. 19 : 61–80).

25 citations

References
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Journal ArticleDOI
TL;DR: The present review is devoted to the exocrine glands derived from epidermis; glands associated with the preoral cavity (mandibular, salivary, etc) and genital apparatus are not dealt with except for the sake of comparison.
Abstract: The present review is devoted to the exocrine glands derived from epidermis; glands associated with the preoral cavity (mandibular, salivary, etc) and genital apparatus are not dealt with except for the sake of comparison. As defined, the epidermal glands manifest an exceptional diversity as far as location, morphology, and func­ tion are concerned. In the past, the studies were mainly anatomical, very rarely cytological, but the interest in insect glands was recently renewed by the chemical approach and the recognized importance of the secretions as far as behavior and physiology are concerned. Concurrently, the high resolution of the transmission electron microscope permitted a far more precise elucidation of the structures, with the hope of establishing some correlations between these structures and the func­ tions. Additionally, the scanning electron microscope appeared well suited for the examination of some cuticular differentiations.

716 citations

Journal ArticleDOI
TL;DR: The detailed structure of the cockroach spermatheca is described and discussed firstly as an example of an insect integumentary gland, and secondly, from the standpoint of its role in reproduction.
Abstract: . The detailed structure of the cockroach spermatheca is described and discussed firstly as an example of an insect integumentary gland, and secondly, from the standpoint of its role in reproduction. The gland comprises a cortical rank of separate secretory units, each associated with an epithelial duct cell responsible for receiving secreted materials and transporting them through the cuticular intima lining the reproductive tract. Secretory activity is cyclic, and the probable mode of elaboration and release of secretory material is described, together with the fine structure of the markedly differing intimas associated respectively with the glandular and conducting units.

101 citations

Journal ArticleDOI
TL;DR: The morphogenesis of Blattella tergal glands, present only in male imagoes and composed of class 3 gland cells, has been studied at the ultrastructural level.

79 citations

Journal ArticleDOI
TL;DR: The spermathecal accessory gland of female Tenebrio molitor is examined by histochemicai and electron microscopical techniques and the product is a glycoprotein.
Abstract: The spermathecal accessory gland of female Tenebrio molitor is examined by histochemicai and electron microscopical techniques. Immediately after ecdysis of the female, neither Golgi regions nor the endoplasmic reticulum of the secretory cells are well developed. In two days' time, the cytoplasm is rich in rough endoplasmic reticulum and the Golgi areas are expanded. Membrane-bound droplets of secretion move from the Golgi zone to a central cavity, formed by the invaginated plasma membrane of this cell. As the secretion accumulates this cavity swells until the fourth day after ecdysis when the females first mate. An efferent cuticular ductule, ensheathed in a ductulecarrying cell, carries the product to the main axial duct of the tubular gland. By histochemical criteria, the product is a glycoprotein.

65 citations

Book
01 Jan 1956

52 citations