Three New Species of Brevitobrilus (Nematoda) with a Discussion on Relationships within the Genus

Three new species of the genus BrevitobriusTsalolikhin, 1981 are described. Brevitobrilus glandulatus n. sp. is characterized by conspicuous sphincter between pars dilatata and uterus; two pairs of vaginal glands; spicules having elliptical capitula with small proximal stiffening piece; proximally-arcuate gubernaculum; S3 and S4 smaller than other supplements; S6 out of spicular range and 57-60 micropapillae. Brevitobrilus dimorphicus n. sp. is diagnosed by sexual dimorphism in labial sensilla and amphids; thick-walled rectum with a diverticulum protruding into intestinal lumen and males with boat-shaped spicules and S6 occasionally slightly smaller than other supplements. Brevitobrilus allahabadensis n. sp. possesses large amphids of 28-33% of corresponding labial diameter in both sexes; vagina and uterus with muscular, plicate walls; well developed sphincter between vas deferens and ejaculatory duct; capitulate spicules with sloping ventral and angular dorsal walls; S3, S4 and S6 smaller than other supplements, S6 close to cloaca and 28-37 micropapillae. The relationships of the species of genus Brevitobrilus have been assessed using morphological characters subjected to parsimony and a non cladistic key to identification of species is given.     

大猿叶虫滞育进程中成虫内生殖系统的形态特征

大猿叶虫Colaphellus bowringi Baly是十字花科蔬菜的一种重要害虫,以成虫在土壤中滞育越冬和越夏。本研究通过解剖大猿叶虫非滞育成虫,观察描述了雌雄成虫内生殖系统的结构特点,并绘制了雌雄成虫内生殖系统模式图。对滞育初期、滞育期间、滞育解除后未取食和滞育解除后取食成虫解剖显示,滞育初期,雌雄成虫内生殖系统几乎与羽化初期成虫一致。滞育期间雄成虫的附腺和射精管亦不发达,滞育解除后未取食雄成虫的附腺膨大且粗于输精管,射精管略膨大,取食雄成虫的射精管呈不透明淡桔黄色。滞育期间雌成虫的卵巢小,略大于滞育初期卵巢,少数卵巢小管的基部可见具卵黄原沉淀的卵粒。滞育解除后未供食雌成虫卵巢明显膨大可见大量成形卵粒,部分卵粒可见卵黄原沉淀;取食雌成虫的卵巢膨大,可见大量成熟卵粒,侧输卵管和总输卵管中可见待产的卵。作者认为,大猿叶虫成虫在滞育期间能够缓慢发育,部分滞育前积累的代谢物质被用于滞育后发育,但只有经过取食,成虫才能正常交配和产卵。     

长足大竹象生殖系统的形态解剖研究

解剖研究了长足大竹象雌雄虫牛殖系统的构造.该虫的雌性生殖系统包括一对卵巢、一对侧输卵管、中输卵管、交配囊、受精囊、生殖腔、产卵器;雄性生殖系统由一对睾九、一对输精管、一对附腺、射精管和交配器组成.     

The male reproductive system and mechanism of sperm transfer in Argulus japonicus (Crustacea: Branchiura)

The histomorphology of the male reproductive system and surface morphology of the “peg-and-socket” in Argulus japonicus are described from serial sagittal and transverse sections and scanning electron micrographs. The prostate complex consists of a glandular part, a reservoir for storing the secretion, and an efferent duct opening into the ejaculatory duct. The openings of both the vas deferens and the prostate duct into the ejaculatory duct are guarded by sphincters. The ejaculatory ducts, which are lined by tall columnar epithelial cells, do not open into the cuticle-lined genital atrium but are blind-ending tubes. This observation and results obtained from observing live specimens, as well as the fact that no spermatophores are formed, suggest that semen could leave the ejaculatory duct only after puncturing of its walls. It is suggested that sperm transfer is accomplished in the following manner: during copulation contraction of the muscular walls of the vas deferens and prostate duct causes semen to be pumped into the ejaculatory duct, which is then closed off by sphincters and a high internal pressure is developed. When a spermathecal spine penetrates the walls of the ejaculatory duct, semen flows from the ejaculatory duct into the spermathecal vesicle due to the higher pressure in the ejaculatory duct. This mechanism is analogous to the sucking up of fluid with a hypodermic syringe. © 1993 Wiley-Liss, Inc.     

Structure of the male reproductive system of the blue swimmer crab Portunus pelagicus (Decapoda: Portunidae)

An attempt was made here to study the structure of the male reproductive system of Portunus pelagicus, which would improve the knowledge base on the reproductive biology of the species and also help in the maintenance of broodstock under controlled conditions. Male P. pelagicus of different sizes were collected from the Palk Bay off Mandapam (9°17′ N, 79°9′ E) and maintained under controlled conditions for the study. Tissues from testis, anterior vas deferens (AVD), median vas deferens (MVD), posterior vas deferens (PVD), ejaculatory duct and penis were fixed in Bouin's fluid and 2.5% buffered glutaraldehyde separately and processed for light and electron microscopic studies, respectively. The reproductive system consisted of testis, commissure, vas deferens, ejaculatory duct and penis. The vas deferens was divided based on the morphology and/or histology into AVD, MVD and PVD. The AVD was further divided based on histology into proximal and distal regions, and the MVD, based on diameter into major and minor coils. The testicular lobe had several lobules with a central seminiferous tubule, which continued till the penis. The seminiferous tubule was lined by a layer of cuboidal or columnar epithelium. The lining of the central tubule of the vas deferens formed several ‘folds’, which at times formed ‘pouches’. High incidence of cell organelles in the columnar epithelial cells, aggregations of vesicles and occurrence of blebs at the luminal periphery and the projection of numerous microvilli containing electron‐dense materials into the lumen from the cell lining denoted high secretory activity of the epithelial cells.     

New species of Trichuris (Nematoda:Trichuridae) from Akodon montensis, Thomas, 1913, of the Paranaense Forest in Argentina

Species of Trichuris (Nematoda:Trichuridae) parasitize a broad range of mammalian hosts. To date, 21 Trichuris species infecting nine families of rodents have been found in North and South America. Trichuris navonae n. sp. is described on the basis of specimens recovered from a species of forest-dwelling mice, Akodon montensis (Cricetidae: Sigmodontinae), from nine localities of Misiones Province, Argentina. A comparison with all the species of Trichuris from North and South American rodents is given. The separation of the new species of Trichuris is based on morphologic and morphometrica features, such as the absence of a spicular tube, the presence of a cylindrical spicular sheath with sharp spines, a non-protrusive vulva, a long anterior-posterior portion of the body, a lengthy spicule, and a proximal and distal cloacal tube. This is the third record of this genus in rodents of the Sigmodontinae from Argentina and the fifth record from South American rodents. Despite the large number of potential host species, only about 1.9% of sigmodontine rodent species have been reported as hosts of Trichuris spp. It is suggested that this number represents but a small fraction of Trichuris spp. that occur in sigmodontine rodents, and that additional survey of this group should yield additional species.     

Morphological changes in eupyrene and apyrene spermatozoa in the reproductive tract of the male butterfly Atrophaneura alcinous Klug

Summary

Eupyrene and apyrene spermatozoa are contained in separate cysts in the testis of the butterfly Atrophaneura alcinous. Spermatozoa of both types from various parts of the male reproductive tract were examined with particular reference to their morphological characteristics. All spermatozoa collected from the vas deferens and the vesicula seminalis were found to be immotile under a dissecting microscope. No spermatozoa of either type were recognized in any part of the ejaculatory duct. Within the testis, eupyrene spermatozoa are present in bundles and each spermatozoon has a slender nucleus with an acrosome and a long flagellum containing mitochondrial derivatives. Two kinds of appendages, lacinate and reticular, are present on the surface of the sperm membrane. They are replaced with an extracellular sheath during passage through the vas deferens. In contrast, apyrene spermatozoa have neither nucleus nor acrosome, whereas a cup-shaped structure was found at the sperm tip instead of the acrosome. Unlike eupyrene spermatozoa, they are surrounded by a concentric sheath outside the sperm membrane in the vas deferens. Individual apyrene spermatozoa and coiled bundles of eupyrene spermatozoa were both found to accumulate in the vesicula seminalis before mating. These morphological changes during passage through the male reproductive tract suggests the occurrence of a kind of maturation and capacitation process reminiscent of mammalian spermatozoa.     

Specific criteria in Grania (Oligochaeta,Enchytraeidae)

The structure of the penial bulb and male efferent duct system of Grania species may be used in addition to setal pattern and spermathecal shape to distinguish species. Six penial bulb types are distinguished: (1) a simple, small, glandular bulb surrounding the male pore; (2) a small, glandular bulb, with a large, associated, dorso-medial gland mass; (3) a small glandular bulb, medial to the male pore, with an elongate male bursa (the aglandular sac), the vas deferens exitting directly into the invaginated male pore; (4) a glandular bulb with an aglandular sac and a small, cuticular stylet embedded in the bulb, extending from the ectal end of the vas deferens; (5) a glandular bulb and an aglandular sac with a long stylet extending from the vas deferens, through the bulb into the sac; and (6) glandular bulb reduced or absent, with or without an aglandular sac; with a long stylet and other prominent modifications, usually muscular, of the vas deferens. The details of the male duct structure were consistent within specimens grouped on the basis of setal distribution and shape and detailed spermathecal structure. Diverse male duct patterns are found within the polytypic species G. macrochaeta and G. postclitellochaeta. The positions of the spermathecal and male pores in their respective segments are distinctive for some species.     

Two New Genera of Marine Tubificidae (Oligochaeta) from Australia's Great Barrier Reef

Macquaridriloides gen.n. is established for M. heronae from Heron Reef in Queensland, Australia. The species is characterized principally by its lack of spermathecae, and its elaborate male efferent ducts, each of which consists of (1) a ciliated vas deferens, (2) a ciliated and muscular atrium with diffuse prostates, and (3) a stout muscular, non-ciliar ejaculatory duct opening into a large copulatory sac surrounded by posterior prostates. The genus appears closely related to Macquaridrilus Jamieson, 1968, the habitat and zoogeography of which are briefly discussed. Heronidrilus gen.n. is established for H. fastigatus sp.n. and H. bihamis sp.n. both from Heron Reef. This genus is closely related to Macquaridriloides , but the two species differ from M. heronae in that they possess spermathecae and lack ejaculatory ducts.     

Development of the genital ducts and spermathecae in the Rhyacodrilines rhyacodrilus coccineus and Monopylephorus rubroniveus (Oligochaeta, tubificidae).

The male genital duct in Tubificidae consists of a funnel, a vas deferens, an atrium, and, frequently, a copulatory structure. There may also be a diffuse or compact prostate gland in association with the duct. The morphogenesis of this duct is described for Rhyacodrilus coccineus and Monopylephorus rubroniveus (Rhyacodrilinae). The funnel and vas deferens in both species originate from peritoneal (mesodermal) cells in the posterior septum in the testis segment. The atrium in R. coccineus develops from a primary epidermal (ectodermal) invagination. A typical atrium is not formed in M. rubroniveus; the entire duct is of mesodermal origin. In the latter species, a shallow epidermal invagination occurs, into which both male ducts open, but it bears resemblance to a copulatory structure, which usually forms from a secondary invagination, rather than to a proper atrium. We therefore conclude that M. rubroniveus lacks an atrium. The copulatory structure is termed the male bursa. Both species have diffuse prostate glands that differentiate from peritoneal (mesodermal) cells surrounding the male duct. In R. coccineus the cells cover the atrium, whereas in M. rubroniveus they cover only a part of the vas deferens. The development of the spermathecae and female ducts is also examined. The spermatheca is of ectodermal origin in both studied species, i.e., it forms as an invagination of the epidermis. The female duct develops from peritoneal (mesodermal) cells in the posterior septum of the ovary segment. However, in M. rubroniveus the first sign of the duct disappears and a proper duct never develops.     

Maturational changes in the survivability and fertility of fowl sperm during their passage through the male reproductive tract

The objective of this study was to examine whether domestic fowl (Gallus domesticus) sperm undergo maturation in their capacity for survival and fertilization in the male reproductive tract. Sperm collected from the testis, epididymis and the proximal, middle and distal vas deferens were simultaneously stored in vitro in minimum essential medium (MEM) at 39°C for 0, 3 and 6h, and at 4°C for 24 and 48h. Sperm membrane integrity was measured using the dual fluorescent stain SYBR-14/propidium iodide (PI). Aliquots of sperm from the various sites were subjected to artificial insemination (AI) into the uteri of hens to assess the duration of sperm survival in the oviduct and to determine the fertility status of the sperm. Testicular sperm exhibited a very low capacity to survive under in vitro liquid storage conditions, irrespective of the storage temperature used, and in the oviduct, and they had a low ability to fertilize the ovum. On the contrary, sperm from the distal vas deferens had a higher survival rate during in vitro storage periods, a longer life span in the oviduct, and high fertility. Survival and fertilizing capacity of the sperm recovered from the testes increased gradually (P<0.05) from the testes to the distal vas deferens. In conclusion, we suggest that fowl sperm may undergo functional maturation through a process of gradual changes in their survival and fertilization capacities during their passage through the successive parts of the male reproductive tract.     

Morphology and development of the male reproductive tract in Callinectes danae (Crustacea: Brachyura)

The aim of this study was to characterize the morphology and function of each section of the reproductive system of male Callinectes danae, as well as the stages of reproductive development and their relation to secondary sexual characteristics. Development of their reproductive system begins after completion of the pubertal moult. The growth of the gonopodium showed negative allometry for both juveniles and adults. The reproductive system is divided into portions with different functions. There is a germinal zone in the testes containing spermatogonia, a zone of maturation containing spermatocytes, spermatids or spermatozoa, as well as a collecting duct, which carries spermatozoa to the vas deferens. There are two matrices in the anterior vas deferens that initiate the separation of spermatozoa groups, one composed of polysaccharide acids (matrix I) and another consisting of neutral polysaccharides (matrix II). In the median vas deferens, the matrix II forms an acellular capsule, which forms the spermatophores. In the posterior vas deferens, the matrices are accumulated, initially with a granular texture and are homogenous for the final portion. The ejaculatory duct and penis have muscle lining to expel the spermatophores at copulation. Even after copulation, males retain a stock of spermatophores, allowing copulation with other females.     

The Vas Deferens of the Spanish Lobster,Scyllarus chacei

Summary

The male reproductive tract of Scyllarus chacei consists of paired testes and vasa deferentia that conduct sperm containing spermatophores to the genital pores at the base of each fifth walking leg. The testis is joined to the vas deferens which can be divided into four regions: (1) the anterior vas deferens can be further divided into three regions. It is highly convoluted and is the region in which the sperm become encapsulated in ovoid spermatophores of approximately 100 sperm as well as produces seminal fluids. (2) The middle vas deferens is the primary site of sperm storage and adds to seminal fluids which formed in the anterior region. (3) The posterior region is highly muscularized and may serve for limited sperm storage. (4) The most distal portion is the ejaculatory duct which is highly muscularized for extruding the spermatophoric mass for transfer to the female. A final seminar product is added here.     

Morphogenesis of the Genital Ducts and Spermathecae in Clitellio arenarius, Heterochaeta costata, Tubificoides benedii (Tubificidae) and Stylaria lacustris (Naididae) (Annelida, Oligochaeta)

The development of the male genital ducts in Clitellio arenarius, Tubificoides benedii, Heterochaeta costata (Tubificidae) and Stylaria lacustris (Naididae) is studied with the purpose of investigating the homologies between different parts of the ducts. In both Tubificidae and Naididae, the male duct comprises a funnel, a vas deferens and an atrium. There may also be a prostate gland (diffuse or compact) in association with the duct. The funnel and vas deferens, in all four species, originate from the peritoneal (mesodermal) cells in the posterior septa in the testes segment, whereas the atrium develops from an epidermal (ectodermal) invagination. The prostate glands have different origins in different taxa; in S. lacustris it differentiates from the peritoneal (mesodermal) cells surrounding the atrium, but in H. costata and T. benedii it develops by a multiplication of the atrial (ectodermal) cells; C. arenarius lacks a prostate gland. The development of the spermathecae and the female duct is also studied. The spermatheca is an epidermal invagination. The female duct is of mesodermal origin. However, the position of the duct differs; in S. lacustris the female duct is lateral and the pore is in the ovarian segment, while in the tubificids studied the duct is ventral with the pore in the segment behind the one containing the ovary.     

中华绒螯蟹(Eriocheir sinensis)雄性生殖系统的组织学研究

中华绒螯蟹雄性生殖系统的组织学研究表明:生精小管一侧为管壁上皮,另一侧为生发区,生殖细胞由生发区基底部同管腔增殖。输精管分为输精细管和贮精囊,管壁上皮具分泌功能,贮精囊有肌肉层。射精管壁肌肉层较厚,粘膜形成纵行皱襞。副性腺内壁为单层立方上皮。生殖系统发育有明显的季节性,8月开始发育加速,10月进入高峰,4月开始发育停滞。     

Morphogenetic derangements in the reproductive system of Bracon hebetor, a beneficial parasitoid, bred on juvenoid treated host (Corcyra cephalonica) larvae

Effect of juvenoids (hydroprene and methoprene) on the ecto-parasite B. hebetor was investigated by rearing them upon the juvenoid treated ultimate instar host larvae of C. cephalonica. Emerged adultoid wasps of either sexes obtained from treated series showed anatomical deformities in the reproductive systems. Ill-developed ovaries with reduced length, terminally free ovarioles and abnormal testicular growth showing non-fusion of lobes were the important abnormal features. Data on measurements of male reproductive system, e.g., width (transverse axis) of testis, length of common vas deferens plus ejaculatory duct and length of accessory gland showed significant difference (P < 0.05) from control.     

3种蛾类雄性内生殖系统形态学研究

为了探究蛾类昆虫新的有效分类特征,本研究对直脉青尺蛾Geometra valida、白雪灯蛾Chionarctia niveus和多斑豹蠹蛾Zeuzera multistrigata雄性内生殖系统进行了解剖观察和形态学比较。结果表明：3种蛾类雄性内生殖系统均由精巢、贮精囊（前贮精囊和后贮精囊）、输精管、复射精管、单射精管（单射精管原节和单射精管表皮节）和附腺组成;种间形态差异表现在贮精囊的形状及连接方式、复射精管的形状及长短、单射精管和附腺的长度等方面,这些鉴别特征可为蛾类分类及系统发育研究提供形态学借鉴。