Bursa Copulatrix Research Articles

A new species of Pupinidius Möllendorff, 1901 (Gastropoda, Stylommatophora, Enidae) from Jiuzhaigou, Sichuan, China.

The genus Pupinidius Möllendorff, 1901 is endemic in China and Nepal and consists of 15 species. China is the distribution centre of it with 12 species being recorded. A new species, Pupinidiuspulchellus Chen, Dai, Wu & Ouyang sp. nov. is described from Jiuzhaigou, Sichuan, China. It can be distinguished from congeneric species by the shell with wide and distinct radial stripes; the thin, slightly reflexed and reddish-brown peristome; the unpointed apex; the unfused A-1 and A-2; the sub-globular and well defined bursa copulatrix; the unexpanded diverticle and the presence of epiphallic caecum.

The mechanoreceptor Piezo is required for spermatogenesis in Bombyx mori

BackgroundThe animal sperm shows high diversity in morphology, components, and motility. In the lepidopteran model insect, the silkworm Bombyx mori, two types of sperm, including nucleate fertile eupyrene sperm and anucleate unfertile apyrene sperm, are generated. Apyrene sperm assists fertilization by facilitating the migration of eupyrene spermatozoa from the bursa copulatrix to the spermatheca. During spermatogenesis, eupyrene sperm bundles extrude the cytoplasm by peristaltic squeezing, while the nuclei of the apyrene sperm bundles are discarded with the same process, forming matured sperm.ResultsIn this study, we describe that a mechanoreceptor BmPiezo, the sole Piezo ortholog in B. mori, plays key roles in larval feeding behavior and, more importantly, is essential for eupyrene spermatogenesis and male fertility. CRISPR/Cas9-mediated loss of BmPiezo function decreases larval appetite and subsequent body size and weight. Immunofluorescence analyses reveal that BmPiezo is intensely localized in the inflatable point of eupyrene sperm bundle induced by peristaltic squeezing. BmPiezo is also enriched in the middle region of apyrene sperm bundle before peristaltic squeezing. Cytological analyses of dimorphic sperm reveal developmental arrest of eupyrene sperm bundles in BmPiezo mutants, while the apyrene spermatogenesis is not affected. RNA-seq analysis and q-RT-PCR analyses demonstrate that eupyrene spermatogenic arrest is associated with the dysregulation of the actin cytoskeleton. Moreover, we show that the deformed eupyrene sperm bundles fail to migrate from the testes, resulting in male infertility due to the absence of eupyrene sperm in the bursa copulatrix and spermatheca.ConclusionsIn conclusion, our studies thus uncover a new role for Piezo in regulating spermatogenesis and male fertility in insects.

Traumatic copulation and counterpart female traits are widespread in fritillary butterflies (Lepidoptera: Nymphalidae: Argynnini)

AbstractFemale fritillary butterflies (Lepidoptera: Nymphalidae: Argynnini) are known to have diversified genital structures, especially at the entrance of the bursa copulatrix. However, the origin and function of such elaborated structures are poorly known to date. We examined the male and female genital structures of six Japanese species selected from five genera/subgenera [Argynnis (Argynnis), Argynnis (Damora), Argynnis (Argyronome), Fabriciana, and Speyeria] of the Argynnini tribe and found that traumatic copulation is widespread in Argynnini. Various male genital structures, such as the uncus, valva, and phallus, can cause wounds to the female genitalia. The eighth venter of the female, where the highest morphological diversity in female genitalia was detected, is hooked and held by the male uncus during copulation. It is very likely that the diversified female genital structure coevolved with the male uncus as a counterpart for traumatic coupling.

Let's wait for the evening: nocturnal copulation in a tropical damselfly Phylolestes ethelae (Odonata, Synlestidae)

Sexual selection is one of the main causes of the diversity of reproductive behaviours observed intra- and interspecifically. Here we study the reproductive behaviour of a unique species, Phylolestes ethelae, the only member of the family Synlestidae (Odonata) found in America. Our hypothesis was that the phylogenetic uniqueness of this species and the fact that it lives on an island would produce novel behaviours worth protecting as they are a part of the biodiversity. Between 2017 and 2019 we studied a population of P. ethelae in the National Park Armando Bermúdez in the Dominican Republic by means of mark-recapture techniques and focal observations. The survival rate was estimated as 0.953 ± 0.012 (SE), which translates into an expected lifespan of 20.6 days. We found that some males showed high site fidelity but very little activity, and territorial disputes were almost inexistent. Females, on the other hand, were rarely observed on the river, and were found mainly on the nearby paths and forest. We recorded 28 tandems and observed a total of 17 copulations, lasting an average of 18.6 min. Examination of sperm volumes in females interrupted during copulation indicated that males removed most of the sperm from the female bursa copulatrix during stage I of copula, but they could not remove sperm from the paired spermathecae. The duration of precopulatory tandem was highly variable (from 3 min to 7.8 h). In some cases, copulation was observed shortly (3 min) after tandem formation, mainly during the morning. However, some pairs formed during the morning, remained in tandem for several hours, and mated late, after dusk. Females laid eggs not accompanied by the male. Mating after the main peak of activity might be a strategy which protects sperm investment because females laying eggs after dusk are unlikely to be mated again that day. Further studies are needed to decipher phenotypic correlates of the males that mate after dusk.

Anatomy of male and female genitalia of Acanthoscelidesobtectus (Say, 1831) (Coleoptera, Chrysomelidae, Bruchinae) in interaction.

Armatures of the male intromittent copulatory structures have been surmised to increase male fitness by imposing physiological costs on female re-mating. Female kicking could, consequently, be a counterstrategy to avoid wounding or to prevent males from mating. The membranous endophallus of male Acanthoscelidesobtectus (Say, 1831) is armed with denticles. Checking if these denticles penetrate the wall of the female genital tract during copulation revealed that only the tip of the median lobe of the aedeagus is intromitted into the female genital opening during copulation. The everted endophallus extends over the full length of the ovipositor, and the spermatophore is placed in the bursa. Identification by means of light microscopy and Micro-CT of the exact relative position of male and female copulatory organs while mated confirmed that the denticles do not cause wounds in the vagina wall. Parts of the inner wall of the bursa copulatrix are covered with inward pointing denticles. Already mated females kick mounting males by vehement movements of their hind legs, thereby preventing mating. In contrast, virgin females usually accept the first male they encounter and terminate copulation by slower movements of their hind legs. The same applied to females who accepted re-mating the second day after the first copulation. Acanthoscelidesobtectus females kick males off to prevent rather than to terminate copulation. Copulatory structures as well as behaviour may have different functional roles in different beetle species, even within the Bruchinae.

Reproductive Biology of Muga Silk Moth <i>Antheraea assamensis</i> Helfer

Results of morphological and morphometric study of male and female reproductive systems of Antheraea assamensis Helfer (Saturniidae: Lepidoptera), a silk moth cultivated exclusively in the North Eastern Region of India are reported herein along with some observations on its reproductive performance in four seasons. The male reproductive system consists of a pair of testes, paired vasa deferentia, seminal vesicle, ductus ejaculatorius duplex, ductus ejaculatorius simplex, an aedeagus and a pair of male accessory glands. The female reproductive system consists of a pair of ovaries, each with four ovarioles, paired lateral oviducts, a common oviduct which has a dorsal protrusion, the vestibulum, a bursa copulatrix, a spermatheca and a pair of female accessory glands with their reservoirs. Fecundity has been found to be positively correlated with female pupal weight in each season. Hatching % of eggs has been found lowest and significantly different (p<0.001) in summer as compared to autumn, winter and spring seasons. Morphology of eupyrene and apyrene sperm bundles and sperm has also been reported.

A New Drymaeus in the Region of Itapebi, Bahia, Brazil (Eupulmonata, Bulimulidae)

Drymaeus nigroflavus is a newly described species found in the region of Itapebi, Bahia, Brazil, near the Jequitinhonha River. This species is characterized by its whitish shell adornedwith dark, spiral bands that are uniform and spaced apart. Its genital system exhibits a veryshort penis and bursa copulatrix, as well as a spermoviduct with a wide, coiled uterus and a verynarrowprostate, among other anatomical idiosyncrasies.

The carboxypeptidase B and carbonic anhydrase genes play a reproductive regulatory role during multiple matings in Ophraella communa.

Seminal fluid proteins (SFPs) are key factors in sexual reproduction and are transferred to females during mating with sperm. SFPs have a nutritional value because they protect and activate sperm storage and release to optimize fecundity. Multiple matings promote ovipositioning in several insect species. Therefore, insects may obtain more SFP through multiple matings to maximize reproduction, but this process has not yet been clearly confirmed. Here, the relationship between multiple matings and the SFPs in Ophraella communa (Coleoptera: Chrysomelidae), a biological control agent of the common ragweed Ambrosia artemisiifolia (Asterales: Asteraceae), was studied. Multiple matings significantly increased female fecundity and ovary egg deposition. Carboxypeptidase B (OcCpb) and carbonic anhydrase (OcCa) genes were identified as putative SFP genes in O. communa and they showed strong male-biased expression. Additionally, OcCpb and OcCa expression was upregulated in the bursa copulatrix of mating females compared to that in virgin females, but their expression gradually declined after copulation. Furthermore, OcCpb and OcCa knockdown in males led to a decrease in insect fecundity compared to that in the control. The reproductive tract of females mated with dsRNA-treated males was dissected and observed and, notably, the ovaries produced significantly fewer eggs. These data suggest that OcCpb and OcCa play regulatory roles during multiple matings in O. communa.

Notes on the female reproductive system of the red‐and‐black froghopper, Cercopis vulnerata Rossi, 1807 (Hemiptera: Cercopidae)‐light and electron microscopy studies

AbstractThe morphology of the female reproductive system in Cercopis vulnerata, an economically important species, was examined with light and scanning electron microscopy techniques. The female reproductive system of C. vulnerata has two ovaries, each containing 14 telotrophic meroistic ovarioles joined by two lateral oviducts that open in a common oviduct. In this type of ovarioles, the trophocytes within the germarium are transferred to the developing oocytes in the vitellarium via the nutritive cords. The oocytes in the vitellarium have three different development stages: previtello, vitello and choriogenesis. The ovarioles open in the lateral oviduct with a thin canal‐shaped pedicel. A pair of lateral oviducts opens distally into the common oviduct. The oviducts are surrounded by a monolayer cubical epithelium with deep folds toward the lumen and a thick muscle layer. A pair of spermatheca and a bursa copulatrix are seen near the common oviduct. Spermatheca has an elongated shape. The bursa copulatrix has an ovoid tube‐like structure. No work has been done on the female reproductive system of Cercopidae to date. This study was conducted to fill this gap and forms part of the female reproductive system morphology of this economically important insect.

Peroxiredoxin 1 transfer during mating protects eupyrene sperm against oxdative stress in Grapholita molesta.

Each Grapholita molesta female only copulates once during its lifetime and thus must maintain the viability of stored eupyrene sperm for male reproductive success. The male ejaculate comprises abundant accessory gland proteins produced by the male accessory gland (AG), and many of which are major effectors for sperm storage and maintenance. Here, we reported that an antioxidant protein, peroxiredoxin 1 (GmolPrx1), secreted by the male AG, is essential for protecting eupyrene sperm from oxidative stress and maintaining their quality during storage in the female bursa copulatrix (BC). Our data showed that GmolPrx1 is highly expressed in the AG of sexually mature males. The GmolPrx1 protein is localized to the cytoplasm of AG cells and delivered to the female BC during mating. Knockdown of GmolPrx1 strongly decreased the fertility of mated females. Additionally, we evaluated oxidative status in the spermatophore of females and found that the content of hydrogen peroxide increased significantly after mating with GmolPrx1 knockdown males. Finally, the quality assessment of eupyrene sperm demonstrated that the plasma membrane integrity, acrosome integrity, and DNA integrity were all severely impaired in the spermatophore of females after mating with GmolPrx1 knockdown males, which may contribute to the fertility decline in males. Our current data demonstrated that activities of eupyrene sperm stored in females can be significantly impaired by enhanced oxidative stress through knocking down of GmolPrx1 in males. Our finding thus may further lay new foundations for the control of G. molesta through suppressing their populations by manipulating male reproductive genes. This article is protected by copyright. All rights reserved.

The North Asian Genus Kolhymamnicola Starobogatov and Budnikova 1976 (Gastropoda: Amnicolidae), Its Extended Diagnosis, Distribution, and Taxonomic Relationships

The taxonomic position and phylogenetic affinities of the endemic North Asian genus Kolhymamnicola Starobogatov and Budnikova, 1976 (Gastropoda: Amnicolidae) remain unknown. To resolve this, we studied key morpho-anatomical characteristics of Kolhymamnicola snails and performed a molecular phylogenetic analysis based on sequences of COI mtDNA, 16S rRNA, and 18S rRNA genes. In terms of protoconch microsculpture, operculum, radular teeth, and gill complex morphology, Kolhymamnicola snails do not differ significantly from the North American genera Amnicola Gould and Haldeman, 1840 and Taylorconcha Hershler et al., 1994, and the European genus Marstoniopsis van Regteren Altena 1936. The bifid penis found in Kolhymamnicola is similar to that in the genus Marstoniopsis. The female reproductive anatomy has some features shared by Kolhymamnicola and Taylorconcha (absence of bursa copulatrix, single seminal receptacle in rs2′ position, and ventral channel). The molecular analysis has revealed Taylorconcha as the closest relative to Kolhymamnicola; the COI-based genetic distance between them amounted to 0.113. We discuss the possible time of divergence of these two genera, as well as of European Marstoniopsis and the Baikal Lake endemic family Baicaliidae. The last common ancestor of these groups was widely distributed in Miocene–Pliocene in the Holarctic waterbodies. Recent Kolhymamnicola snails are distributed in Northern Asia, including lakes of the Baikal rift zone. We rank the Baicaliidae as a family rather than a subfamily of Amnicolidae based on their distinct, unique morpho-anatomical characteristics and highly supported separate position on the molecular tree. The tribe Erhaiini Davis and Kuo, 1985 is elevated to the rank of the family, with 3–4 recent genera included. The family Palaeobaicaliidae Sitnikova et Vinarski fam. nov. is established to embrace the Cretaceous North Asian gastropods conchologically similar to the recent Baicaliidae and Pyrgulidae.

Five new species of the genus Leucania Ochsenheimer in Central America (Lepidoptera: Noctuidae)

Five new species of the noctuid genus Leucania in Central America are described: L. mopan Adams and McCabe, sp. nov., L. merga Adams and McCabe, sp. nov., L. championi Adams and McCabe, sp. nov., L. colorada McCabe and Adams, sp. nov., L. sororia McCabe and Adams, sp. nov. The internal genitalia are key to resolving the taxonomy in this genus; in particular, the morphology of the male everted endophallus (vesica) and the female bursa copulatrix jointly resolve taxonomic confusion among cryptic species near L. albifasciata, L. oaxacana and L. humidicola. We recognize the valvular pore plate and the "poma" (bubble-like structure at base of valvae) as generic synapomorphies for Leucania. Lappets (inflatable pouches on the outer aspect of the valvae) are newly described. Descriptions and color illustrations of the imagos, male valvae, everted endophalli, and the female bursae copulatrix are provided for all newly described species and selected congeners to aid identification. Additional nomenclatorial actions are: Leucania complicata Strecker, 1898 rest. stat.; Leucania februalis Hill, 1924 syn. nov., a junior synonym of L. humidicola; Leucania elephas Troubridge 2020 syn. nov., a junior synonym of L. humidicola.

The Structure of the Female Genital System of the Diving Beetle Scarodytes halensis (Fabricius, 1787) (Hydroporinae, Dytiscidae), and the Organization of the Spermatheca and the Spermathecal Gland Complex

The fine structure of the female reproductive organs of the diving beetle Scarodytes halensis has been described, with particular attention to the complex organization of the spermatheca and the spermathecal gland. These organs are fused in a single structure whose epithelium is involved in a quite different activity. The secretory cells of the spermathecal gland have a large extracellular cistern with secretions; duct-forming cells, by their efferent duct, transport the secretions up to the apical cell region where they are discharged into the gland lumen. On the contrary, the spermatheca, filled with sperm, has a quite simple epithelium, apparently not involved in secretory activity. The ultrastructure of the spermatheca is almost identical to that described in a closely related species Stictonectes optatus. Sc. halensis has a long spermathecal duct connecting the bursa copulatrix to the spermatheca-spermathecal gland complex. This duct has a thick outer layer of muscle cells. Through muscle contractions, sperm can be pushed forwarding up to the complex of the two organs. A short fertilization duct allows sperm to reach the common oviduct where eggs will be fertilized. The different organization of the genital systems of Sc. halensis and S. optatus might be related to a different reproductive strategy of the two species.

On the little-known click-beetle genus Rostricephalus (Coleoptera: Elateridae: Lissominae), with description of a new species from China

Summary Rostricephalus Fleutiaux, 1918 is an enigmatic and little-studied genus. A new species of this genus, Rostricephalus shii n. sp., is described from Sichuan Province, China. The female genitalia of the new species are illustrated and compared with those of the previous only known species, Rostricephalus vitalisi Fleutiaux, 1918. The sclerites of the bursa copulatrix show taxonomic value in distinguishing the species in this genus. The type specimens of R. vitalisi are re-examined and illustrated for the first time, and the lectotype is designated. A distribution map is provided for all literature records of Rostricephalus. The discovery of the new species extends the distribution range of Rostricephalus to south-central Sichuan of China.

Fine structure of the female genital system of diving beetle Stictonectes optatus (Seidlitz, 1887) (Dytiscidae-Hydroporinae) and evidence of mating plug formation

The general organization of the female genital system of the diving beetle Stictonectes optatus was studied, clarifying the complex structure of the spermatheca and spermathecal gland. The two structures adhere closely to each other, sharing a small area of their cuticular epithelium. A long duct connects the bursa copulatrix to the spermatheca, where the sperm are stored. The sperm reach the common oviduct, where egg fertilization occurs, via a fertilization duct. The spermathecal gland cells have extracellular cisterns where secretions are stored. Thin ducts composed of duct-forming cells transport these secretions to the apical gland region and into the spermathecal lumen. Soon after mating, the bursa copulatrix is almost completely occupied by a plug secreted by the male accessory glands. The secretions of the bursa epithelium seem to contribute to plug formation. Later this plug becomes large and spherical, obstructing the bursa copulatrix.

Female control of sperm ejection and retention in the cornsilk fly Euxesta eluta (Diptera: Ulidiidae).

Promiscuous mating systems provide the opportunity for females to bias fertilization toward particular males. However, distinguishing between male sperm competition and active female sperm choice is difficult for species with internal fertilization. Nevertheless, species that store and use sperm of different males in different storing structures and species where females are able to expel all or part of the ejaculates after copulation may be able to bias fertilization. We report a series of experiments aimed at providing evidence of female sperm choice in Euxesta eluta (Hendel), a species of ulidiid fly that expels and consumes ejaculates after copulation. We found no evidence of greater reproductive success for females mated singly, multiply with the same male, or mated multiply with different males. Female E. eluta possesses two spherical spermathecae and a bursa copulatrix for sperm storage, with a ventral receptacle. There was no significant difference in storing more sperm in spermathecae 24 h after copulation than immediately after copulation. Females mated with protein-fed males had greater reproductive success than similar females mated to protein-deprived males. Protein-fed females prevented to consume the ejaculate, retained more sperm when mated to protein-fed males than when mated to protein-deprived males. Our results suggest that female E. eluta can exert control of sperm retention of higher quality males through ejaculate ejection.

The hsp70 new functions as a regulator of reproduction both female and male in Ophraella communa.

Heat shock proteins (Hsps) function as molecular chaperones that enable organisms to withstand stress and maintain normal life activities. In this study, we identified heat shock protein 70 (encoded by hsp70), which exhibits a higher expression in the mature male testis than in the unmature testis of Ophraella communa. Tissue expression profile revealed that Ochsp70 levels in males were highest in the testis, whereas those in females were highest in the head. Moreover, the expression of Ochsp70 was found to be significantly induced in female bursa copulatrix after mating. Double-stranded RNA dsOchsp70 was injected into males to performance RNA interference, which significantly decreased the male Ochsp70 expression levels within 20 d post-injection, whereas no effect was observed on the Ochsp70 expression level in the females after mating with dsOchsp70-injected males. However, significant downregulation of female fertility was marked simultaneously. Furthermore, knockdown of female Ochsp70 expression also led to a significant reduction in fertility. Finally, comparative transcriptomic analysis identified glucose dehydrogenase and insulin-like growth factor binding protein as putative downstream targets of Ochsp70. Overall, we deduced that Ochsp70 is an indispensable gene and a potential male mating factor in O. communa, which regulates reproduction.

The Functional Morphology of the Bursa Copulatrix of a Butterfly That Does Not Digest Spermatophores (Leptophobiaaripa, Pieridae).

The bursa copulatrix of female Lepidoptera is a complex organ where crucial male-female reproductive interactions occur during and after copulation. The bursa copulatrix receives, stores, and digests the spermatophore and other substances transferred by the male during copulation, and is involved in changes in female receptivity, ovogenesis, and oviposition. Although females of the butterfly Leptophobia aripa do not digest the spermatophore, they possess a prominent signum. Since, in general, the function of the signum is considered to be the piercing or tearing of the spermatophore to initiate its digestion, its presence in L. aripa poses a conundrum. We undertook a microscopic study of the different components of the bursa copulatrix (ductus bursae and corpus bursae) and found structural differences that we interpreted in functional terms. We provide a detailed description of the signum and present experimental data regarding its effect on the spermatophore. Our observations led us to propose a novel hypothesis regarding the function of the signum.

Morphology of Immature Stages and Adults of Helicoverpa Armigera

Helicoverpa armigera (Hübner) is a highly polyphagous insect pest of worldwide occurrence, including India. In the present study, a detailed morphological assessment of H. armigera showed the following: typically dome-shaped egg with ribbed surface; larva having coriaceous skin, biordinal crochets and 11 primary setae on the prothoracic segment; pupa adecticous and obtect with prominent posterior tip cremaster; and adult forewings characterized by the presence of 7-8 black spots along the apical margin and a reniform shaped brown marking, more prominent on the underside. Adults exhibit sexual dimorphism in the colour of vestiture and forewings. The genitalic traits like the presence of usually 12 or less sets of cornuti in aedeagus, apically broadened harpe having length ranging between 4.5 to 4.9 mm and a single lobe at the base of everted vesica in males, and four distinct signa on bursa copulatrix in females, also distinguishes it from other congeneric species.

Morphological and Genetic Variability in Radix auricularia (Mollusca: Gastropoda: Lymnaeidae) of Lake Baikal, Siberia: The Story of an Unfinished Invasion into the Ancient Deepest Lake

This article aims to reconstruct the invasion of the ear-shaped pond snail, Radix auricularia (Linnaeus, 1758), to Lake Baikal, East Siberia. This species is widely distributed in the Palaearctic and Northern America, and since the early 20th century has formed abundant and sustained populations in Lake Baikal. The data provided on the morphological and genetic variability of R. auricularia help to better describe and delineate the species. With an integrative approach involving morphological and molecular data, we improved the knowledge of the intraspecific variability of R. auricularia in the most important characteristics used for its determination. Molecular sequences of nuclear spacer fragment ITS-2 and mitochondrial gene fragment cyt–b were obtained from 32 individuals of Radix (including seven outgroup Radix species) collected from various parts of Lake Baikal and adjacent waterbodies and compared with sequences of 32 individuals of R. auricularia from different regions of the Palaearctic as well as with individuals determinated as R. intercisa from Lake Baikal, R. iturupica from the Kurile Islands, R. ussuriensis from the Khabarovsk region, R. narzykulovi from Tajikistan, and R. schubinae from the Amur region. Molecular genetic analyses revealed that all specimens collected from Lake Baikal belong to R. auricularia. There are no genetically distinct groups of snails that would correspond to two morphospecies previously recorded in Lake Baikal (e.g., R. auricularia s. str. and R. intercisa). Variability of the characteristics that are commonly used for species identification (shell morphology, mantle pigmentation, shape and position of the bursa copulatrix, length and position of the bursa duct, length ratio of preputium to penial sheath) were found in individuals analysed with molecular genetics to be broader than recognised in the current literature. Some shells of R. auricularia collected from Lake Baikal resemble shells of another lymnaeid species, R. balthica, and without molecular assessment can be confused with the latter. Geometric morphometric analysis of more than 250 shells revealed no observed hiatus between Baikalian and non-Baikalian R. auricularia. The probable stages and pathways of R. auricularia invasion to Lake Baikal’s ecosystem are outlined and discussed. Factors such as global climate warming and human activity stimulated and facilitated the ongoing dispersal of ear pond snails within Lake Baikal.