Paired Seminal Vesicles Research Articles

New species of Polycystididae (Platyhelminthes: Kalyptorhynchia) from Cuba and the Pacific coast of Panama

Four new species of marine polycystidid microturbellarians (Platyhelminthes, Kalyptorhynchia) are described from Cuba and Panama. These species are Brachyrhynchoides ortizi sp. nov., Djeziraia adriani sp. nov., Phonorhynchoides lalanai sp. nov., and Sabulirhynchus ibarrae sp. nov. All species occur in Cuba, and P. lalanai sp. nov. was also retrieved from the Pacific coast of Panama. From the latter locality, we also report Sabulirhynchus axi Artois & Schockaert, 2000. All species are readily distinguished from their congeners by the morphology of the sclerotised structures of the male genital system. The prostatic stylet of B. ortizi sp. nov. is the shortest and widest known for Brachyrhynchoides. Djeziraia adriani sp. nov. can be recognized by its paired seminal vesicles and S-shaped prostate stylet. The prostatic stylet of P. lalanai sp. nov. is proximally twisted and the length proportion between its accessory and prostatic stylet is the largest among all known species of Phonorhynchoides. Sabulirhynchus axi and Sabulirhynchus ibarrae sp. nov. are morphologically similar, yet the latter species is unique due to the characteristic ridge in the middle of the proximally tubular prostatic stylet. With the data available today, a possible explanation of rhabdocoel biogeographic patterns across the Isthmus of Panama remains largely speculative.

Structural and histological observations on the male reproductive system of adult red poplar leaf beetle Chrysomela populi Linnaeus, 1758 (Coleoptera: Chrysomelidae).

This study described the anatomy and histology of the male reproductive system in Chrysomela populi, which is an economically important species belonging to the family Chrysomelidae. Therefore, reproductive biology has been studied to combat this insect. As well as, the characters associated with the reproductive tract have been potential to discuss aspects of the system and to better understand the reproductive dynamics. The male reproductive system of C. populi has a pair of testes, a pair of vas efferentia and deferentia, a pair of seminal vesicles, a pair of accessory glands, an ejaculatory bulb, an ejaculatory duct, and an aedeagus. The testis consists of two flower-shaped lobes. Each testis has 20 sperm tubules (testicular follicles) containing cysts of germ cells at various developmental stages within the light orange peritoneal sheath. Testicular follicles are composed of three different (growth, maturation, and differentiation) zones. In the middle region of each testis joins with the vas efferens. The testis is attached to the seminal vesicle by a small stalk like vas efferens. In the lumen of the vas efferens, seminal vesicle, and vas deferens, sperms form clumps in the form of thin threads. The proximal end of the vas deferens is connected to the common ejaculatory duct. It joins with the ejaculatory bulb. Around the ejaculator bulb, there is a pair of convoluted, flat-surface tubular structure accessory glands. Posterior ejaculatory duct joins with the aedeagus.

Anatomy and histology of reproductive system of adult male mint leaf beetle Chrysolina herbacea (Duftschmid, 1825) (Coleoptera: Chrysomelidae).

In this study, anatomy and histology of the male reproductive system of Chrysolina herbacea (Duftschmid 1825) (Coleoptera: Chrysomelidae) are described and illustrated by using light and scanning electron microscopies. Data from the male gonad of this species provide more extended and precise knowledge regarding the histoanatomical structure of the reproductive system in Chrysomelidae. The male reproductive system in C. herbacea consists of paired bilobed testes, two paired vas efferentia, paired seminal vesicles, paired vas deferentia, paired tubular accessory glands, a ductus ejaculatorius, and an aedeagus. Each testis consists of 40 follicles enveloped in a yellow pigmented sheath. In the light and scanning electron microscope examinations of male reproductive system of C. herbacea, different spermatogenesis stages (spermatocytes, spermatids, and spermatozoa) are found. Each testes follicle joins with the vas efferens surrounded by monolayered cubic epithelium with oval nuclei. Epithelial cells are covered from the outside with a thin layer of muscle and sheath. Vas efferens connect to vas deferens that may have an enlarged and differentiated region = seminal vesicle. Mature spermatozoa are seen in the lumen of the vas efferens, seminal vesicle, and vas deferens. There is a pair of accessory glands with a convoluted appearance in the tubular structure around the vas deferens. The vas deferens is a straight tube which leads into the proximal end of the ductus ejaculatorius. Ductus ejaculatorius wall is surrounded by intima, monolayer epithelium, and a thick muscle layer with many nuclei. The distal section of the ductus ejaculatorius is housed within the aedeagus.

Morphology and histology of the male reproductive system of Collaria oleosa (Distant, 1883) (Heteroptera: Miridae)

Collaria oleosa (Distant, 1883) is a phytophagous bug often observed causing injuries in wheat, barley, and oat crops, besides grass pastures. The male reproductive system of C. oleosa has been studied anatomically and histologically. It consists of a pair of testes, each one with two follicles, one pair of seminal vesicles, two pairs of external accessory glands, and an ejaculatory bulb. The testicular follicles exhibit cysts with spermatogonia, spermatocytes, spermatids, and spermatozoa bundles. The testes are connected to the seminal vesicles by the vas deferens. The seminal vesicles are connected to the ejaculatory bulb and are bound by the accessory glands. In mirids belonging to the Stenodemini tribe, the general morphology of the male reproductive system is similar. However, two follicles per testis may be characteristic of the genus Collaria. The anatomy and histology of the male reproductive system in C. oleosa provides new information and also contributes to the understanding of the systematics of Stenodemini as well as the Miridae family in general.

More new Diplotrema earthworm species from southern Mexico (Annelida, Crassiclitellata, Acanthodrilidae, Acanthodrilinae).

Three new Acanthodrilinae species from the states of Oaxaca, Tabasco and Chiapas in southern Mexico are described, Diplotrema oaxacana sp. nov., Diplotrema tabascensis sp. nov., and Diplotrema kaxyebensis sp. nov., respectively. D. oaxacana sp. nov. is characterized by the presence of genital setae in segments 8 and 9, a spermathecal ampulla transversally connected to the duct and paired seminal vesicles in 11 and 12. D. tabascensis sp. nov. is separated from all Diplotrema species by genital setae in segment 16. The singleton D. kaxyebensis sp. nov. is characterized by a single pair of seminal vesicles in 12, genital setae in 8 and by a particular arrangement of spermathecal duct-ampulla-diverticulum connections. It is discussed that the neotropical Diplotrema species lineage does probably not belong to the southern hemisphere Diplotrema lineage, which indeed contains the majority of species; its taxonomic separation, however, should wait until more information is obtained on the molecular relationships among neotropical Acanthodrilinae. Finally the topic of describing new earthworm species on singletons is discussed; a decision table is provided to help earthworm taxonomists to decide about this aspect. This paper is dedicated to Dr. Pietro Omodeo for his important contribution to the fields of taxonomy and biogeography of earthworms, on the occasion of his 100th birthday.

The adult musculature of two pseudostomid species reveals unique patterns for flatworms (Platyhelminthes, Prolecithophora).

We analyzed the adult musculature of two prolecithophoran species, Cylindrostoma monotrochum (von Graff, 1882) and Monoophorum striatum (von Graff, 1878) using a phalloidin‐rhodamine technique. As in all rhabdithophoran flatworms, the body‐wall musculature consisted of three muscle layers: on the outer side was a layer of circular muscle fibers and on the inner side was a layer of longitudinal muscle fibers; between them were two different types of diagonally orientated fibers, which is unusual for flatworms. The musculature of the pharynx consisted of a basket‐shaped grid of thin longitudinal and circular fibers. Thick anchoring muscle fibers forming a petal‐like shape connected the proximal parts of the pharynx with the body‐wall musculature. Male genital organs consisted of paired seminal vesicles, a granular vesicle, and an invaginated penis. Peculiar ring‐shaped muscles were only found in M. striatum, predominantly in the anterior body part. In the same species, seminal vesicles and penis only had circular musculature, while in C. monotrochum also longitudinal musculature was found in these organs. Female genital organs were only present in M. striatum, where we characterized a vagina interna, and a bursa seminalis. Transverse, crossover, and dorsoventral muscle fibers were lacking in the middle of the body and greatly varied in number and position in both species.

The histomorphological structure of the male reproductive system of maize leaf weevil Tanymecus dilaticollis Gyllenhal, 1834 (Coleoptera: Curculionidae).

The histomorphology of the reproductive system and the germ cells has been useful to establish phylogenetic relationships in many insects. However, these elements remain little known in the Curculionidae. In this study, histomorphological structure of the male reproductive system of Tanymecus dilaticollis, which is economically important, is described, illustrated using stereomicroscopy, light microscopy, and scanning electron microscopy techniques, and discussed in relation to other Coleoptera species. Results showed that distinctive features of the male reproductive system of T. dilaticollis consist of a pair of yellowish testes, a pair of seminal vesicles, a pair of vasa deferentia, an ejaculatory duct, accessory glands, prostate glands, and aedeagus. Each testis is subdivided into two testicular follicles, enclosed by a peritoneal sheath. Each follicle of the mature testes is full sperm cysts with germ cells at various stages development of spermatogenesis. The testes have four types of germ cells (spermatogonia, spermatocytes, spermatids, and spermatozoa). They are occupied by the growth zone containing spermatogonia and spermatocytes, the maturation zone containing spermatids, while differentiation zone containing spermatozoa. There is a seminal vesicle at the center of each testis. Most mature sperms are stored in the seminal vesicle. Each testis is attached to the vas deferens by a stalk-like seminal vesicle. In the distal part, vasa deferentia fuse with the ejaculatory duct. It is linked to the aedeagus. The provided results will contribute to the understanding of the reproductive cell biology of Curculionidae.

Scrotal circumference: A predictor of testosterone concentration and certain attributes of seminal vesicles influencing buffalo male fertility.

Aim:The aim of this study was to evaluate the relationship of scrotal circumference (SC) with plasma testosterone, seminal vesicles (SVs) weight, and its secretion as measurable indicators of fertility and also to sequence and establish phylogenetic relatedness of certain SV protein genes with other species as such integrated approach is lacking.Materials and Methods:Altogether, 59 apparently healthy male buffaloes sacrificed at slaughterhouse were selected (irrespective of breed) for measuring SC and collecting blood and paired SVs. The SC was measured at greater curvature using soft thread. In the present study, blood plasma testosterone, cholesterol, protein, and glucose in addition to SV fructose, citric acid and proteins in SV fluid were also estimated. The SV tissue was fixed in RNAlater for RNA extraction. Male buffaloes were categorized as per total SV weight into Group I (<5.0 g), Group II (5.0-7.84 g), and Group III (>8.0 g) and dentitions-I (≤18 months), II (18-24 months), and III (≥24 months) to assess the effect of weight and dentition age on SC, SV weight, and its certain secretions. Data were analyzed using linear model procedure including Tukey HSD test and Pearson’s correlation coefficient. Variance inflation and condition index were also used to assess multicollinearity.Results:Gross and histomorphological evaluation of SVs did not show any abnormality. Macronutrients (plasma protein, glucose, and cholesterol) showed non-significant (p>0.05) variation between groups. The SC and SV weight varied significantly (p<0.05) with a significant positive relationship with plasma testosterone, SV protein, fructose, and citric acid. In addition, testosterone concentration also showed increasing trend from Groups I to III but increased significantly (p<0.05) from Group II to III with positive and significant correlations with SV protein, fructose, and citric acid similar to SV weight and SC. Binders of sperm protein (BSP1, 3, and 5) genes (full length) were sequenced and established an evolutionary relationship which is lacking in buffalo.Conclusion:The present findings established a significant positive correlation of SC with that of other fertility parameters related to SVs weight and its secretions: Fructose, citric acid, and protein (inclusive of BSPs sequenced full length), and testosterone. Therefore, the present integrated approach along with certain semen quality attributes reflecting epididymis function could be used as a predictive fertility marker for grading and selection of breeding bulls and their progenies to develop outstanding bull mother farm.

Ultrastructure of male reproductive system of Eurydema ventrale Kolenati 1846 (Heteroptera: Pentatomidae).

The male reproductive system of Eurydema ventrale Kolenati 1846 is studied morphologically and histologically by using light, scanning and transmission electron microscopes. The reproductive system of the male E.ventrale consists of a pair of testis, a pair of vas deferens, a pair of seminal vesicles, accessory glands, a bulbus ejaculatorius, a pair of ectodermal sacs, and a ductus ejaculatorius. The testicular follicles have three different development zones (growth zone, maturation zone, and differentiation zone). The testes are connected to the seminal vesicles by the vas deferens that is a specialized in sperm storage. Sperm have an elongated head and a tail (flagellum) with an axonema and two mitochondrial derivatives. Vas deferens and seminal vesicles are fine, long, and cylindrical. The seminal vesicle is connected with bulbus ejaculatorius, which is balloon shaped and surrounded with accessory glands. The bulbus ejaculatorius is continuous with ductus ejaculatorius which is connected to the aedeagus.

The morphology and histology of the male reproductive system in Dolycoris baccarum Linnaeus 1758 (Heteroptera: Pentatomidae)—Light and scanning electron micoscope studies

The male reproductive system of Dolycoris baccarum (Linnaeus 1758) is studied morphologically and histologically using both light and scanning electron microscopes (SEM). The reproductive system of the male D. baccarum consists of a pair of testis, a pair of vas deferens, a pair of seminal vesicles, accessory glands (mesadenia, ectadenia), a bulbus ejaculatorius, a pair of ectodermal sacs, and a ductus ejaculatorius. The number of testicular follicles varies from four to six. The testicular follicles have three different development zones (growth zone, maturation zone, differentiation zone). The testes are connected to the seminal vesicles by the vas deferens. Vas deferens and seminal vesicles, which are fine-long and cylindrical. The seminal vesicle is connected with bulbus ejaculatorius which is balloon-shaped and surrounded with accessory glands. The bulbus ejaculatorius is continuous with ductus ejaculatorius which connected to the aedeagus.

Morphological characters for using species identification of Chaetognaths

Chaetognaths are elongated, slender, silindirical shaped and bileterally simetrical mostly zooplanktonic organisms. Their length change between 2 and 100 mm. Their bodies are consisted of three segments: head, trunk and tail. They have gasping spines and tooth on each sides of the head, there is a pair of eyes in the dorsal part of the head and corona cilliata streching onto the trunk part. There are gut diverticule, collerette, ventral ganglion, ovarium, anterior fins and part of posterior fins in trunk. In the caudal area there is another part of posterior fins and a pair of seminal vesicles. These characters show difference among chaetognath species and they are also used to characterize the species. A few studies were done about chaetognaths of Turkey coast in the literature so this study is aimed to be a written source for the systematic investigation of chaetognaths.

Male genital organs in the eulittoral meiofaunal polychaete Stygocapitella subterranea (Annelida, Parergodrilidae): ultrastructure, functional and phylogenetic significance

The marine interstitial polychaete Stygocapitella subterranea is characterized by aberrant morphological and biological traits resembling those of clitellates and Hrabeiella periglandulata, a terrestrial polychaete species. Although clearly related to the terrestrial Parergodrilus heideri, there are distinct differences in their morphology. An ultrastructural study of the male genital organs was undertaken to look for common apomorphic features in Parergodrilidae, to find structural evidence for clarifying their reproductive biology and mode of sperm transfer. Finally it should be elucidated whether a supposed sister-group relationship of Parergodrilidae and Orbiniidae based on molecular evidence can be supported by morphological characters as well. In S. subterranea the male organs consist of an unpaired seminal vesicle, a pair of sperm ducts and two large tube-like prostate glands. These glands constitute the distal parts of the gonoducts and open ventrally on a small genital papilla in chaetiger 9. True copulatory organs or organs for storage of mature sperm are lacking. The seminal vesicle is a coelomic cavity composed of two apposed coelomic linings supplied with blood spaces. The testes are found ventrally. The prostate glands are covered by a single layer of muscle fibres running in a longitudinal/spiral direction along the gland. There are no signs of spermatophore formation in any part of the male system. Since females always carry sperm, pseudocopulation can be excluded and the likelihood of either direct transfer of sperm or hypodermic injection is discussed. The structure of genital organs reveals similarities to those of P. heideri. Gonochorism, paired seminal vesicles and two pairs of male gonoducts opening in chaetigers 9 and 10 with a distal glandular part most likely belong to the ground pattern of Parergodrilidae. The observations confirm that consistencies with either clitellates or H. periglandulata are the result of convergent evolutionary events. On the other hand, the relationship of Parergodrilidae to an orbiniid/questid clade receives support from the present data.

The OECD Program to Validate the Rat Hershberger Bioassay to Screen Compounds for in Vivo Androgen and Antiandrogen Responses: Phase 2 Dose–Response Studies

ObjectiveThe Organisation for Economic Co-operation and Development (OECD) has completed phase 2 of an international program to validate the rodent Hershberger bioassay.DesignThe Hershberger bioassay is designed to identify suspected androgens and antiandrogens based on changes in the weights of five androgen-responsive tissues (ventral prostate, paired seminal vesicles and coagulating glands, the levator ani and bulbocavernosus muscles, the glans penis, and paired Cowper’s or bulbourethral glands). Protocol sensitivity and reproducibility were tested using two androgen agonists (17α-methyl testosterone and 17β-trenbolone), four antagonists [procymi-done, vinclozolin, linuron, and 1,1-dichoro-2,2-bis-(p-chlorophenyl)ethylene (p,p’-DDE)], and a 5α-reductase inhibitor (finasteride). Sixteen laboratories from seven countries participated in phase 2.ResultsIn 40 of 41 studies, the laboratories successfully detected substance-related weight changes in one or more tissues. The one exception was with the weakest antiandrogen, linuron, in a laboratory with reduced sensitivity because of high coefficients of variation in all tissue weights. The protocols performed well under different experimental conditions (e.g., strain, diet, housing protocol, bedding, vehicle). There was good agreement and reproducibility among laboratories with regard to the lowest dose inducing significant effects on tissue weights.ConclusionsThe results show that the OECD Hershberger bioassay protocol is reproducible and transferable across laboratories with androgen agonists, weak androgen antagonists, and a 5α-reductase inhibitor. The next validation phase will employ coded test substances, including positive substances and negative substances having no androgenic or antiandrogenic activity.

Variation of male reproductive apparatus in relation to fertilization modalities in the catfish families Auchenipteridae and Callichthyidae (Teleostei: Siluriformes)

To investigate the relationship between fertilization modalities and the morphology of male reproductive apparatus, two species of Auchenipteridae, Auchenipterus nuchalis and Tatia intermedia, and six species of Callichthyidae, Callichthys callichthys, Corydoras aeneus, Corydoras bondi, Corydoras ehrhardti, Corydoras potaroensis and Hoplosternum littorale were studied. The species analysed show either internal or external fertilization, the latter including the so called ‘sperm drinking’ type of mating. An anal fin modified as an intromittent organ, a pair of seminal vesicles, and the release of sperm in the form of discrete bundles (spermatozeugmata) characterize the male reproductive apparatus of the internal fertilizer A. nuchalis. Seminal vesicles are present also in C. aeneus, C. bondi, C. ehrhardti, C. potaroensis and H. littorale, species performing ‘sperm drinking’ spawning. In contrast, regardless of the family, species showing the more classic type of external fertilization lack specialized accessory organs. Where occurring, the major function of seminal vesicles is the secretion of mucins. The role of these mucosubstances, in relation to spermatozeugmata formation, in internal fertilizers, or the protection of sperm passing through the female gut, in the ‘sperm‐drinking’ species, is discussed. Variation, between families, in the shape of testis and accessory structures, as well as in the type of spermatogenesis was found. Neither the reproductive modalities nor the phylogenetic relationships, however, appear to fully account for these differences.

Morphometry of the testis follicles in Triatoma rubrofasciata (De Geer, 1773) (Hemiptera, Triatominae)

Abstract The male reproductive tract in Triatominae has a pair of testes, two vasa deferentia, a pair of seminal vesicles, four pairs of accessory glands, and an ejaculatory duct, which opens in the aedeagus. In species of the genus Triatoma each testis is formed by seven testicular follicles. Because Triatoma rubrofasciata has a common ancestor with species of Triatoma occurring in North America and because the length of testis follicles varies among different species of Triatoma a morphometrical analysis of the follicles was conducted. Triatoma rubrofasciata has seven testis follicles of variable length that are similar between left and right testes. The statistics allowed the classification in a long follicle, two medium follicles, two that are short, and two that are very short. This finding is compared with data available for other Triatominae and it is emphasized that the length of follicles testis should be included in future phylogenetic analysis of Triatominae.

The OECD Program to Validate the Rat Hershberger Bioassay to Screen Compoundsfor in Vivo Androgen and Antiandrogen Responses. Phase 1: Use of a Potent Agonistand a Potent Antagonist to Test the Standardized Protocol

The Organisation for Economic Cooperation and Development (OECD) has completed phase 1 of the Hershberger validation intended to identify in vivo activity of suspected androgens and anti-androgens. Seventeen laboratories from 7 countries participated in phase 1, and results were collated and evaluated by the OECD with the support of an international committee of experts. Five androgen-responsive tissues (ventral prostate, paired seminal vesicles and coagulating glands, levator ani and bulbocavernosus muscles, glans penis, and paired Cowper’s or bulbourethral glands) were evaluated. The standardized protocols used selected doses of a reference androgen, testosterone propionate (TP), and an antiandrogen, flutamide (FLU). All laboratories successfully detected TP-stimulated increases in androgen-responsive tissue weight and decreases in TP-stimulated tissue weights when FLU was co-administered. The standardized protocols performed well under a variety of conditions (e.g., strain, diet, housing protocol, bedding). There was good agreement among laboratories with regard to the TP doses inducing significant increases in tissue weights and the FLU doses decreasing TP-stimulated tissue weights. Several additional procedures (e.g., weighing of the dorsolateral prostate and fixation of tissues before weighing) and serum component measurements (e.g., luteinizing hormone) were also included by some laboratories to assess their potential utility. The results indicated that the OECD Hershberger protocol was robust, reproducible, and transferable across laboratories. Based on this phase 1 validation study, the protocols have been refined, and the next phase of the OECD validation program will test the protocol with selected doses of weak androgen agonists, androgen antagonists, a 5α-reductase inhibitor, and chemicals having no androgenic activity.

Inhibitory effect of all-trans retinoic acid on androgen-induced growth of mouse seminal vesicles in vivo and its mechanism

We examined the effect of all-trans retinoic acid (ATRA) on the androgen-induced growth of mouse seminal vesicles (SVs) in vivo and its mechanisms. Testosterone propionate (TP) alone or with ATRA was injected daily into adult castrated BALB/c mice. Injections of ATRA significantly inhibited the TP-induced growth of SVs in terms of wet weight and DNA synthesis by a pair of SVs evaluated by [3H]thymidine uptake. The bromodeoxyuridine labelling index showed that ATRA inhibited the proliferation of both epithelial and stromal cells. Immunoreactivity for retinoic acid receptor-alpha was found in the basal epithelial cells. Injections of ATRA affected neither 5alpha-reductase activity nor the expression of mRNAs for TGF-beta1, 2 and 3 and TGF-beta receptor 1 and 2 in the SVs. However, androgen receptor (AR) binding assays and Western blotting revealed a decrease in AR without a change in ligand-binding affinity. The present study showed that retinoid inhibited the androgen-induced growth of mouse SVs in vivo, and suggests that a decrease in AR is one of its mechanisms.

Male genital organs, spermatogenesis and spermatozoa in the enigmatic terrestrial polychaete Parergodrilus heideri (Annelida, Parergodrilidae)

The terrestrial polychaete species Parergodrilus heideri (Parergodrilidae) has many features in common with the Clitellata and with Hrabeiella periglandulata, another terrestrial species of the Annelida. An ultrastructural investigation of the male genital organs, spermatogenesis and spermatozoa was undertaken in P. heideri to elucidate whether similarities to these taxa might exhibit adaptive characters typical of terrestrial annelids in general or synapomorphies. In P. heideri the male organs consist of a pair of seminal vesicles situated in chaetigers 6–9 and two pairs of ciliated sperm ducts opening into a genital atrium together with numerous accessory gland cells in chaetiger 10. In addition, the enlarged chaetae of this last chaetiger are probably copulatory chaetae. The seminal vesicles consist of coelomic spaces supplied with blood vessels. The vesicles originate from the mesentery, where the pair of testes are also found. Mitotic divisions within the testes produce spermatogonia, which are released into the vesicles where they undergo further divisions. The spermatids develop on typical cytophores although only four cells are present on each cytophore. In contrast to previous reports, the spermatozoa are of the so-called modified type; the head comprises the elongated acrosome and nucleus, and in the midpiece eight ovoid mitochondria surround the distal centriole, which gives rise to the axoneme. A small proximal centriole is present, which is oriented parallel to the distal one. Acrosome and tail are set off by two prominent infoldings of the cell membrane. The specific characters observed in P. heideri are typical of species with direct transfer of sperm and internal fertilisation. However, there are no synapomorphies with either the Clitellata or H. periglandulata; the similarities between these terrestrial Annelida are very likely due to a corresponding reproductive biology in similar habitats and thus do not reflect a common ancestor.

Interstitial fauna of the Galapagos: Duplacrorhynchinae, Macrorhynchinae, Polycystidinae, Gyratricinae (Platyhelminthes Polycystididae)

Seven species from the Galapagos of different subfamilies of the Polycystididae are described and discussed. Four of them are new to science, three of which belong to the subfamily Duplacrorhynchinae Schockaert & Karling 1970: Djeziraia incana n. sp. differs from the other species of the genus by its long, thin stylet; Phonorhynchoides haegheni n. sp. is unique within the genus, as the prostate stylet is much shorter than the accessory stylet; Parachrorhynchus jondelii n. sp. is characterised by the presence of a bundle of atrial glands, paired seminal vesicles, a very large sphincter at the distal end of the female duct, and a ring of hard plates at the distal end of each ovary. of the Macrorhynchinae Evdonin 1977, Macrorhynchus manusferrea n. sp. differs from the other species of the genus by the shape of the stylet and the presence of a female bursa. The subfamily Polycystidinae Schockaert & Karling 1970 is represented by Polycystis ali Schockaert 1982 and Paulodora felis (Marcus 1954). The Galapagos p...

Genetic architecture of testis and seminal vesicle weights in mice.

Comparisons across 13 inbred strains of laboratory mice for reproductive organ (paired seminal vesicles and paired testes) weights indicated a very marked contrast between the C57BL/6By and NZB/BINJ mice. Subsequently these strains were selected to perform a quantitative genetic analysis and full genome scan for seminal vesicle and testis weights. An F(2) population was generated. The quantitative genetic analyses indicated that each was linked to several genes. Sixty-six short sequences for length polymorphism were used as markers in the wide genome scan strategy. For weight of paired testes, heritability was 82.3% of the total variance and five QTL contributed to 72.8% of the total variance. Three reached a highly significant threshold (>4.5) and were mapped on chromosome X (LOD score 9.11), chromosome 4 (LOD score 5.96), chromosome 10 (LOD score 5.81); two QTL were suggested: chromosome 13 (LOD score 3.10) and chromosome 18 (LOD score 2.80). Heritability for weight of seminal vesicles was 50.7%. One QTL was mapped on chromosome 4 (LOD score 9.21) and contributed to 24.2% of the total variance. The distance of this QTL to the centromere encompassed the distance of the QTL linked with testicular weight on chromosome 4, suggesting common genetic mechanisms as expected from correlations in the F(2). Both testis and seminal vesicle weights were associated with a reduction in the NZB/BINJ when this strain carried the Y(NPAR) from CBA/H whereas the Y(NPAR) from NZB/BINJ in the CBA/H strain did not modify reproductive organ weights, indicating that the Y(NPAR) interacts with the non-Y(NPAR) genes. The effects generated by this chromosomal region were significant but small in size.