Sperm storage by spermatodoses in the spermatheca of Trioza alacris (Flor, 1861) hemiptera,psylloidea, triozidae: A structural and ultrastructural study

Female insects generally store sperm received during mating in specific organs of their reproductive tract, i.e., the spermathecae, which keep the sperm alive for a long time until fertilization occurs. We investigated spermatheca morphology and ultrastructure in the psylloidean insect Trioza alacris (Flor, 1861 ) in which spheroidal sperm packets that we refer to as ‘spermatodoses’ are found after mating. The ectoderm‐derived epithelium of the sac‐shaped spermatheca that has a proximal neck, consists of large secretory and flat cuticle‐forming cells. Secretory cells are characterized by a wide extracellular cavity, bordered by microvilli, in which electron‐dense secretion accumulates before discharge into the spermathecal lumen. The cuticle‐forming cells produce the cuticular intima of the organ and a peculiar specialized apical structure, through which secretion flows into the lumen. At mating, the male transfers bundles of sperm cells embedded in seminal fluid into the spermathecal neck. Sperm cells proceed towards the spermathecal sac lumen, where they are progressively compacted and surrounded with an envelope that also encloses secretions of both male and female origin. We describe the formation of these sperm containing structures and document the contribution of the female secretion to spermatodose or female‐determined spermatophore construction. We also discuss the choice of the term ‘spermatodose’ for T. alacris and suggest it be used to refer to sperm masses constructed in the female reproductive organs, at least when they involve the contribution of female secretion. © 2011 Wiley Periodicals, Inc.     

Characteristics of aminopeptidase activity of female housefly reproductive accessory glands

Proteolytic activity was detected in crude extracts of female reproductive accessory glands and the following characteristics of the principal aminopeptidase activities were determined: substrate specificity, pH optima, molecular weights, and effects of inorganic salts. The greatest aminopeptidase activities were found with the β-naphthylamides of: alanine at pH 7.5 and 9.5, leucine at pH 8.0, and methionine at pH 6.5. The methionine-specific activity in the crude extract was stimulated 3 times by 100 mM MgCl₂, CaCl₂, NaCl, or KCl. Inhibition was noted, and ID₅₀ was determined for each of the other principal substrates with the following salts: CdCl₂, CaCl₂, ZnCl₂, HgCl₂, MgCl₂, and MnCl₂. Molecular weights, estimated on Sephadex G-200 and on Sepharose-6B, were found to be around 210 000 for each of these principal aminopeptidase activities in the crude extract.     

Structure of male accessory glands of Bolivarius siculus (fischer) (Orthoptera,Tettigoniidae) and protein analysis of their secretions

In Tettigoniidae (Orthoptera), male reproductive accessory glands are involved in the construction of a two‐part spermatophore; one part, the spermatophylax, is devoid of sperm and considered a nuptial gift. The morphology, ultrastructure, and secretion protein content of the male reproductive accessory glands from Bolivarius siculus were investigated. Two main groups of gland tubules open into the ejaculatory duct: the “first‐order” glands, a number of large anterior tubules, and the “second‐order” glands, smaller and more numerous tubules positioned posteriorly. Along with a further subdivision of the gland tubules, we here describe for the first time an additional gland group, the intermediate tubules, which open between first and second‐order glands. The mesoderm‐derived epithelium of all glands is a single layer of microvillated cells, which can be either flattened or cylindric in the proximal or distal region of the same gland. Epithelial cells, very rich in RER and Golgi systems, produce secretions of both electron‐dense granules and globules or electron‐transparent material, discharged into the gland lumen by apocrine or merocrine mechanisms, respectively. With one exception, a unique electrophoresis protein profile was displayed by each of the gland types, paralleling their unique morphologies. To assess the contribution of different types of accessory glands to the construction of the spermatophore, the protein patterns of the gland secretions were compared with those of the extracts from the two parts of the spermatophore. All samples showed bands distributed in a wide range of molecular weight, including proteins of very low molecular mass. However, one major high molecular weight protein band (>180 kDa) is seen exclusively in extracts from the first‐order glands, and corresponds to an important protein component of the spermatophylax. J. Morphol., 2009. © 2009 Wiley‐Liss, Inc.     

The ultrastructure of the ejaculatory duct in the springtail Orchesella villosa (Geoffroy) (Hexapoda, Collembola) and the formation of the spermatophore

The initial part of the ejaculatory duct of Orchesella villosa contains a “valve” and a “sorter” avoiding respectively the reflow and allowing the separation of the secretion for the spermatophore stalk from the sperm fluid. For most of its length, the ejaculatory duct lumen is divided into two parts: in the dorsal part the sperm fluid flows while in the ventral district the secretion for the stalk occurs. Laterally, on both sides of the duct, longitudinal muscle fibers are present. The epithelium of the dorsal region consists of two types of long secretory cells; the most peculiar of them are those provided with extracellular cisterns flowing directly into the duct lumen as it occurs in 1st type of epidermal cells. These cells could be involved in the control of the viscosity of the sperm fluid. The second type of cells produce a secretion probably involved in the formation of the outer coat of the apical sperm droplet. The ventral epithelium consists of short cells contributing to the enrichment of the secretion for the spermatophore stalk and perhaps also to the viscosity of the secretion flowing in the lumen. In the distal part of the ejaculatory duct, the ventral district is provided with a thick layer of muscle fibers and with 3 + 3 cuticular laminae dividing the lumen into a series of slits through which the secretion of the stalk is squeezed out into filaments. This organization allows the twisting and hardening of these filaments. A drop of sperm fluid is laid on top of the long and rigid spermatophore stalk.     

Reproductive apparatus and male accessory structures in two batrachoid species (Teleostei, Batrachoididae)

The morphology of the genital apparatus of two batrachoid species, Opsanus tau and Porichthys notatus , was studied. The anatomical organization of the female reproductive apparatus is similar in both species but differences are observed in the rhythm of gametogenesis with individual oocyte production asynchronous in O. tau and group synchronous in P. notatus. The male reproductive apparatus is similarly organized in the two species, with both showing enlongated testes with an efferent duct system, two main testicular ducts, a common sperm duct, and a pair of multi-channel accessory structures. The sperm transport system consisting of the efferent duct system, main testicular ducts, and sperm duct is more developed in P. notatus and only in this species does it secrete sialoglycoproteins. Male accessory organs also secrete sialoglycoprotein in both species, but they appear more developed in O. tau. Intraspecific variability in development of accessory structures and mucin secretion was also observed between the two male morphs of P. notatus. Type I males, which build nests and perform parental care to eggs and fry, have larger accessory organs and more abundant secretion than type II males, which adopt opportunistic spawning tactics. The possible role played by mucins as components of the seminal fluid, in both species, and their inter-and intraspecific variability are discussed in the light of the reproductive biology and the presence of alternative male mating tactics.     

Little-known accessory glands in female Zygaena moths (Lepidoptera, Zygaenidae)

In the female genital system of Zygaena moths, an additional pair of accessory glands is present besides the Y-shaped sebaceous gland. The term 'Petersen's glands' is proposed for these organs. Anatomy, histology, histochemistry and cytology of Petersen's glands of Zygaena trifolii are described. The sac-like glands, situated in the extreme dorsocaudal part of the abdomen, can be divided into a purely secretory part consisting of acini with large pear-shaped gland cells and a reservoir part with combined secretory and storage function. The secretory cells of the acini are penetrated by long curved ductules or secretory end apparatuses having feltwork consisting of very fine filaments. The cytoplasm is characterized by abundance of smooth tubular endoplasmic reticulum (ATER) and the presence of peroxisomes. This cytoplasmic organization is in accordance with the chemical composition of the sticky secretion, which evidently consists completely of lipids. The ultrastructure of the epithelium lining the reservoir of the glands has both traits of secretory and of transporting epithelia. Besides contributing to the secretion, it may be involved in absorption of residual aqueous phase from the contents of the reservoir.     

Ultrastructure and function of the labial nephridia and the rectum of Orchesella cincta (L.) (Collembola)

Summary The collembolan Orchesella cincta possesses a well-developed coelomoduct kidney. The presence of podocytes in the wall of the sacculus and the fact that the epithelium of the nephridial tubule has the ultrastructural characteristics of resorbing cells, indicate that this is an ultrafiltration-reabsorption kidney.Apparently also the rectum is lined by a reabsorptive epithelium; the cells possess an extensive system of apical and basal infoldings. This view is sustained by the fact that the stereology of the apical channel system varies in animals kept under different moisture conditions. During the intermoult period, both organs are subject to strong morphological changes, which are obviously related to the feeding rhythm.The authors wish to thank Dr. T. Sminia for his stimulating interest during the investigations, Dr. J.C. Jager for statistical advice and Mr. G.W.H. van den Berg for drawing the figures     

Functional morphology of the female reproductive apparatus of Stephanitis pyrioides (Heteroptera,Tingidae): A novel role for the pseudospermathecae

At mating, female insects generally receive and store sperm in specific organs of their reproductive tract called spermathecae. Some Heteroptera, such as Cimicomorpha, lack a true spermatheca; some have receptacles of novel formation where sperm cells can transit or be stored. In Tingidae, there are two sac‐like diverticula, the “pseudospermathecae,” each at the base of a lateral oviduct, which previously were considered to function as spermathecae. However, this role has never been documented, either by ultrastructural studies or by observations of sperm transit in the female reproductive tract. In this article, we investigate the morphology and the ultrastructure of the female reproductive apparatus in the economically important tingid species Stephanitis pyrioides, focusing our attention on the functional role of the pseudospermathecae in an evolutionary perspective. Each ovary consists of seven telotrophic meroistic ovarioles, the long pedicels of which enlarge into a bulb‐like structure near the terminal oocyte. The ovarioles flow into two long lateral oviducts, which join to form a very short common oviduct. Basally, each lateral oviduct is connected through a short duct to one of two pseudospermathecae. The ultrastructure of the ectodermal epithelium of the pseudospermathecae is dramatically different in sexually immature or mated females. In virgin females, cells delimit a very irregular lumen, filled with a moderately electron‐dense granular material. The large nucleus adapts to their irregular shape, which can have long projections in some regions and be flattened in others. After mating, epithelial cells generally elongate and display an apical layer of microvilli extending beneath the cuticle, often containing mitochondria. In the lumen of the pseudospermathecae there is a dense brownish secretion. No sperm cells were ever found inside this organ. After mating, sperm move upward along the lateral oviducts and the ovarioles, accumulating in the bulb‐like structure of the pedicels, and proceeding into the distal region between the follicle cells surrounding the oocyte and the ovariole wall. The egg, most likely fertilized in the bulb‐like region of the ovariole, moves through the lateral oviduct, entirely enters the pseudospermatheca and is smeared with its secretion just before oviposition. We exclude a function of sperm storage for the pseudospermathecae, and instead suggest a novel role for these organs as reproductive accessory glands. J. Morphol., 2010. © 2009 Wiley‐Liss, Inc.     

Ultrastructure of the male accessory glands ofAllacma fusca(Insecta, Collembola)

The accessory glands ofAllacma fusca(L.) (Insecta, Collembola, Sminthuridae) consist of a series of secretory units that are arranged in parallel and open into the ejaculatory duct. Each unit is composed of microvillate cells stacked around a common cavity. Basal cells are involved in ion-control of fluids from the hemocoel to the cavity. The intermediate and apical cells, which have a laminar appearance and contain many microtubules, are involved in the structural integrity of the unit. Supporting cells ensheath the most apical cells. Large openings in the cuticle allow the gland secretion to flow into the ejaculatory duct lumen. These openings are protected by a porous cuticle different from that lining the epithelium of the ejaculatory duct. Conspicuous muscle fibers run along the lateroventral side of the ejaculatory duct beneath the insertion of the accessory glands. The fine structure of the accessory glands indicates that they are type I ectodermic glands as defined by Noirot & Quennedey (1974). Their function could be to control the fluidity of the material for spermatophore formation and to ensure the proper physiological conditions for spermatozoa stored in the ejaculatory duct lumen.     

Eicosanoids: their biosynthesis in accessory sex organs of Lymnaea stagnalis (L.)

Summary

High performance liquid chromatography has been used to identify the eicosanoids produced from radiolabelled arachidonic acid by accessory sex organs of Lymnaea stagnalis. Radiolabelled compounds co-eluting with the primary prostaglandins normally associated with invertebrates were present, together with two eicosanoids known to occur in vertebrates. These results lend support to the suggestion of van Duivenboden (Int. J. Invertebr. Reprod., 6 (1983) 249–257) that prostaglandins (PGs) are involved in accelerating the onset of egg laying in female copulants of this species. The inability of indomethacin and aspirin to completely inhibit PG biosynthesis in L. stagnalis suggests that the PG synthetase of this snail differs from that of mammals and most other invertebrates.     

Histological study of the spermatheca in three thelytokous parthenogenetic ant species,Pristomyrmex punctatus,Pyramica membranifera and Monomorium triviale (Hymenoptera: Formicidae)

Gotoh, A., Billen, J., Tsuji, K., Sasaki, T. and Ito, F. 2011. Histological study of the spermatheca in three thelytokous parthenogenetic ant species, Pristomyrmex punctatus, Pyramica membranifera and Monomorium triviale (Hymenoptera: Formicidae). —Acta Zoologica (Stockholm) 00 :1–8. The evolution of obligate parthenogenesis may induce the degeneration of female mating ability and subsequently affect the morphology of the female reproductive organs related to mating and/or sperm storage. Here, we investigated the size and structure of the sperm storage organ, the spermatheca, in three thelytokous parthenogenetic myrmicine ant species, Pristomyrmex punctatus, Pyramica membranifera and Monomorium triviale, and compared it with that of their related sexually reproducing species. So far, mated individuals have never been found in these three species, which appears to be in line with their parthenogenetic status. Although the spermatheca appears to be useless in these species, we could not find any evidence on the degeneration in size and morphology of their spermathecae. The spermathecal reservoir still has the columnar hilar epithelium, which is one of the major features for a functional spermatheca in ants.     

黄胫小车蝗受精囊的亚显微结构

利用组织学方法,观察了黄胫小车蝗Oedaleus infernalis 受精囊的显微与亚显微结构。结果表明,黄胫小车蝗受精囊为单个,由高度卷曲的受精囊管和蚕豆状的端囊构成。受精囊壁主要由表皮层、上皮层、基膜和肌肉层构成;上皮层包含上皮细胞、导管细胞和腺细胞。上皮细胞在靠表皮层的边缘有大量的微绒毛,两相邻上皮细胞的细胞膜相互嵌入,并有细微的突起延伸在导管细胞及腺细胞之间,直到基膜,达基膜处的上皮细胞膜折叠,与腺细胞膜的折叠,一起形成迷宫样的指状突起,附着在基膜上。导管细胞有一个较大的核和分泌导管,连接于腺细胞的细胞腔和受精囊腔,将腺细胞中分泌物运输到受精囊腔中。腺细胞具有典型的分泌细胞特征： 含发达内质网、高尔基复合体及不同大小的囊泡。肌肉层位于受精囊最外层,附在基膜上。在受精囊不同部位的结构有差异。在交配前和交配后,受精囊腺细胞的亚显微结构也有差异。     

Paternity Analysis in a Hexapod (Orchesella cincta; Collembola) with Indirect Sperm Transfer

In species where males and females interact during mating, the role of females in sexual selection cannot always be demonstrated unambiguously. Here we present a model system to study female choice for mates. Orchesella cinca is a soil-dwelling hexapod with indirect sperm transfer. Females and males do not interact physically for reproduction. We gave females the choice between spermatophores produced by two different males. Paternity analysis based on microsatellite variation revealed that offspring in one clutch were sired by one male only. Direct observations showed that after a female has taken up a spermatophore, the female's receptivity to further spermatophore uptake seem to end. Our results imply that the female is in full control of paternity.     

The embryological origin of the juxtatesticular body in jawfishes (Opistognathidae)

A male accessory sex organ, termed the juxtatesticular body (JTB), is located in the posterior part of the trunk, outside the coelomic cavity, lying ventral to the urinary ducts and dorsal to the urinary bladder and testes in jawfishes. Its microscopic structure is unusual for an accessory sex organ because it is highly vascularized, organized in small follicles, and ductless. The embryological origin of the JTB and the development of the urogenital apparatus was studied in juveniles of Opistognathus whitehurstii and O. maxillosus . Both sexes possess a structure located outside the coelomic cavity in the posterior part of the trunk. In females this structure showed the same histological organization as the kidney, however in males it was different and recognized as the JTB. The degree of development of the JTB followed that of the testes, being represented in youngest recognizable males only by a small mass of mesenchymal cells while it was fully developed in males with spermatogenic testes. In most immature males renal structures, such as tubules and glomeruli, were found in the dorsal part of this structure. On the basis of anatomical and cytological features a nephrogenic origin for the JTB is proposed.     

Ultrastructure of male accessory glands of Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae)

The ultrastructure of the male accessory glands of the blow fly, Chrysomya megacephala (Fabricius), was presented using light microscopy (LM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). A pair of accessory glands was separated at opposite sites. Morphometric results using LM yield evidenced no significant difference in the median of either length or width of the left and right glands. A significant increment in both length and width was seen to plateau between three to six days. SEM observation showed that the surface of the glands revealed a faint irregular groove pattern throughout, and it was occasionally penetrated by tracheoles. Each gland was a slender, elongated sac‐like tubule having apical rounded ends, with a slight constriction at the sub‐apical part of the gland being observed occasionally. TEM analyses of three‐day‐old males showed that the glands consisted of external capsular cells with a basement membrane underneath, glandular cells, and gland lumen. The capsular cell was flat and contained a nucleus with electron dense material in the nuclear envelope. The glandular cell, appearing as columnar, consisted of a vacuolated component that contained a large oval nucleus centrally or sub‐basally located, with dense mitochondria, numerous rough endoplasmic reticulum, and secretory vesicles containing electron‐lucent materials. In the gland lumen, the cross‐section through the middle portion revealed dense secretory materials, characterized by electron‐dense materials. Some sections revealed a large lumen where secretion accumulates within the delicate sac. The seven‐day‐old glands exhibited a remarkable change in the lumen, where the whole space contained a large amount of secretory materials, with the electron‐dense materials being characterized as similar to those observed in three‐day‐old glands. About four prominent types of secretions were observed on the basis of difference in electron‐density.     

Seasonal changes in the fine structure of the accessory sex gland in the mole (Talpa europaea)

The mole has a single pair of accessory sex organs with features of both the prostate and the seminal vesicle, for which the term prostate gland is not appropriate. Seasonal changes occuring in this gland were related to four periods: a) the quiescence period, b) the maturation period, c) the active period and d) the involution period. During the quiescence period the cuboidal epithelial cells display a quasi-embryonic fine structure and are sparse in cytoplasmic organelles, but rich in glycogen and lipopigment. With the onset of sexual activity glycogen and lipopigment disappear and the rough endoplasmic reticulum as well as the Golgi apparatus begin to proliferate. The fully active gland is lined by a low epithelium with parallel stacks of rough endoplasmic reticulum, a large Golgi apparatus and several lysosomes and secretory granules. In the involution period the gland collapses and the epithelial cells are eliminated by hetero- and autophagic processes. During this period a great number of presumably endocrine cells were observed. The results were compared with findings in experimental studies and those on postnatal development of accessory sex glands in laboratory animals.     

Sperm aggregations in the spermatheca of the red back salamander (Plethodon cinereus)

The spermatheca of Plethodon cinereus is a compound tubular gland that stores sperm from mating in early spring (March–April) to oviposition in summer (June–July). The seasonal variation of sperm storage in this species has previously been studied by light and transmission electron microscopy. In this paper, sperm aggregations, interaction of sperm with the spermathecal epithelium, and spermathecal secretions are studied using scanning electron microscopy. Within spermathecal tubules, relatively small groups of sperm are aligned along their entire lengths in parallel arrays. This pattern is similar to other plethdontids with complex spermathecae. Lumina of spermathecal tubules are filled with secretory material in April prior to the arrival of sperm, and after sperm appear, a coating of secretory material persists on the apices of the spermathecal epithelium. Sperm peripheral to the central luminal mass can become embedded in the secretory matrix or pushed deeper into the spermathecal epithelium. The spermathecal secretions may serve to attract and prolong the viability of sperm, but sperm that become enmeshed in the secretions or epithelium are phagocytized. Sperm and spermathecal secretions are largely absent after ovulation and in summer months, and new secretory vacuoles are formed in fall, although mating does not occur until spring.     

Sperm aggregations in the spermatheca of female desmognathine salamanders (Amphibia: Urodela: Plethodontidae)

The alignment of sperm in a cloacal sperm storage gland, the spermatheca, was studied in female desmognathine salamanders by scanning and transmission electron microscopy. Females representing nine species and collected in spring, late summer, and fall in the southern Appalachian Mountains contained abundant sperm in their spermathecae. The spermatheca is a compound tubuloalveolar gland connected by a single common tube to the middorsal wall of the cloaca. Sperm enter the common tube in small groups aligned in parallel along their axes, and continue in a straight course until encountering divisions of the common tube (neck tubules) or luminal borders of distal bulbs, which can act as barriers. Sperm may form tangles, in which small clusters retain their mutual alignment, at the branches of the neck tubules from the common tube, or in the lumen of the distal bulbs, where subsequent waves of sperm collide with sperm already present. The nuclei of some sperm from the initial group to encounter the walls of the distal bulbs appear to become embedded in secretory material on the luminal border or in the apical cytoplasm of the spermathecal epithelial cells. We propose that these sperm become trapped in the spermatheca and are ultimately degraded. J. Morphol. 238:143–155, 1998. © 1998 Wiley-Liss, Inc.