Courtship and sperm transfer in Charinus neocaledonicus Kraepelin, 1895 and Charinus australianus (L. Koch, 1867) (Arachnida, Amblypygi, Charinidae)

The Charinus australianus group is a well-defined species group characterised by rounded, cushion-like female gonopods. Before the present study, the morphology of the gonopods and their function have not been understood. This paper describes courtship behaviour, spermatophore morphology, and the morphology of the female genitalia of Charinus neocaledonicus Kraepelin, 1895 and C. australianus (L. Koch, 1867). Courtship behaviour, though different in details, is similar to that of many other species. The spermatophores are large and soft and carry very small sperm packages, each with a short stalk. After sperm transfer, the spermatophore may be eaten by the female. The spermatophore thus transfers not only spermatozoa but also nutritious paternal investment to the female. Each female gonopod is equipped with a seminal receptacle consisting of an atrium and a spacious inner receptacle. The cover of the atrium can be elevated by high blood pressure and pulled back by a group of muscles attached to the inner part of the receptacle. The female probably picks up the sperm packages with the atria of her receptacles. The observations are compared to those on other amblypygids, and the evolution of different types of spermatophores and of gonopods with seminal receptacles is discussed.     

Courtship Behavior of the Cumberland Plateau Woodland Salamander,Plethodon kentucki (Amphibia: Plethodontidae), with a Review of Courtship in the Genus Plethodon

Complete catalogs of courtship behavior are available for only seven of the 42 currently recognized species of Plethodon. Additional detailed studies of courtship behavior in Plethodon species are needed to analyze the evolution of courtship behavior in this genus. We investigated the courtship behavior of the Cumberland Plateau woodland salamander (Plethodon kentucki) and compared it to previous accounts of courtship in other Plethodon species. In the laboratory, we videotaped the complete courtship of 30 different P. kentucki pairs, which included 46 tail-straddling walks that resulted in spermatophore deposition. From a transition matrix of observed motor patterns, we constructed a flow diagram of significant motor-pattern transitions during courtship. In general, the courtship behavior of this species is very similar to that of other large eastern Plethodon; however, there are some notable differences. Prior to the tail-straddling walk, the male transfers courtship pheromone from his mental gland to the female's nasolabial grooves (via mental-gland tapping and ‘chin-to-chin’ behavior patterns) more frequently than in other Plethodon. In most courtships, the female initiates contact leading to the tail-straddling walk. Males exhibit a greater propensity to deposit multiple spermatophores per courtship (two deposited in 33% of courtships, three deposited in 10% of courtships, X = 1.53 spermatophores per courtship) than males of other plethodontids. Mean size of the spermatophore is smaller than in other large eastern Plethodon. Overall, the courtship behavior of this species is most similar to that of P. jordani.     

Ultrastructure and histochemistry of the male reproductive system of the genus Callinectes Stimpson, 1860 (Brachyura: Portunidae)

We described the ultrastructure and histochemistry of the reproductive system of five Callinectes species, and evaluate the seasonal variation in weight of the reproductive system and hepatopancreas by comparing annual changes of somatic indices. The somatic indices changed little throughout the year. In Callinectes, spermatogenesis occurs inside the lobular testes and, within each lobule, the cells are at the same developmental stage. Spermatogenesis and spermiogenesis follow the same development pattern in all Callinectes studied. Mature spermatozoa are released into the seminiferous ducts through the collecting ducts. Cells of the vas deferens are secretory as evidenced by rough endoplasmic reticulum, Golgi complex, and secretory vesicles that produce the seminal fluid. The anterior vas deferens shows two portions: proximal and distal. In proximal portion (AVDp), spermatozoa are clustered and embedded in an electron-dense, basophilic glycoproteinaceous secretion Type I. In the distal portion (AVDd), the spermatophore wall is formed by incorporation of a less electron-dense glycoproteinaceous secretion Type II. The secretion Type I change to an acid polysaccharide-rich matrix that separates the spermatophores from each other. The median vas deferens (MVD) stores the spermatophores and produces the granular glycoproteinaceous seminal fluid. The posterior vas deferens (PVD) has few spermatophores. Its epithelium has many mitochondria and the PVD seminal fluid changes into a liquid and homogeneous glycoprotein. Many outpocketings in the PVD and MVD help to increase the fluid production. Overall, the reproductive pattern of Callinectes is similar to other species that produce sperm plugs. The secretions of AVD, MVD, and PVD are responsible for the polymerization that forms the solid, waxy plug in the seminal receptacle. The traits identified here are common to all Portunidae species studied so far.     

Carotenoids in the spermatophores of bushcrickets (Orthoptera: Ephippigerinae)

During mating male bushcrickets transfer large spermatophores, which have been demonstrated to play an important role in female nutrition and egg production. Until now only relatively unspecific substances such as water and proteins were known to be present within these spermatophores. We found that in the bushcricket Ephippiger zelleri the spermatophores contain substantial amounts of carotenoids (mainly lutein and zeaxanthin) that are also found in the eggs of this species. Carotenoids are well known for their positive effects on survival and reproduction in animals. This is the first example, to our knowledge, where such specific vitamin-like substances were found to be transferred from male to female during mating.     

The effect of body size on male courtship success in a plethodontid salamander

Two different sets of courtship encounters between female Desmognathus ochrophaeus and males of large (X¯=58) and small (X¯=38 mm) body size were staged in the laboratory. In the first set, encounters were arranged between male-female pairs so that each of five females individually encountered each of 10 males. In these encouters, small and large males were equally likely to court with and inseminate females. In the second set, each encounter was staged for a trio fo one female and two males (one large and one small); each female had a courtship opportunity with five large-small pairs of males, and each pair of males encountered five different females. In the 25 trio encounters, the large male always chased away the small male before proceeding to court the female. Small males never deposited spermatophores if a large male was present. Male body size should have a significant effect on courtship success in natural populations of D. ochrophaeus if male-male competition affects access to females.     

Le comportement reproducteur de Sminthurus viridis (L.) (Collembola,Symphypleona)

Different phases of the reproductive behaviour of Sminthurus viridis are analysed. Stalked spermatophores are deposited by the ♂, but the sperm is transmitted during a primitive courtship. Oviposition consists of characteristic sequences, present in all species which deposit coated eggs. Here, however, the shortness of the sequences results from the eggs being laid in batches and from the frequently dry conditions in the natural biotope of this species. The anatomy of the genital organs of ♂♂ and ♀♀ is described, with a particular study of the genital plate of the ♂ by SEM.     

Mate feeding, offspring investment, and sexual differences in katydids (Orthoptera: Tettigoniidae)

Food stress in the katydid Requena veriicalis (Orthoptera: Tettigoniidae)decreases the relative availability of males able to supplynutritious spermatophores to females and increases the valueof the male courtship meal (i.e., relative male parental investment).These changes cause female sexual competition in katydid populations.Here we examine the effect of food stress on male and femaleinvestment in single offspring and test the prediction thatmale-derived nutrients in eggs increase relative to nutrientsfrom the female's reserves. We varied the diet of female R.veriicalis and determined the fate of nutrients from male andfemale sources using I4C and 3H radiolabeled amino acids. Low-dietfemales retained more nutrients from male and female sourcesin somatic tissues and invested less in reproduction both becausethey produced fewer eggs and because they invested less peroffspring (egg) than females maintained on a high-quality diet.Moreover, opposite to our prediction, relative male investmentin individual eggs decreased in foodstressed females; femalesretained more nutrients in somatic tissues from the male sourcethan the female source. Food-stressed females may retain nutrientreserves, particularly those from the male, as an adaptive trategyfor immediate survival needs and future reproduction. Such afemale strategy is unlikely to compromise male reproductivesuccess; first-male sperm precedence means that males matingwith virgin females are likely to father most eggs laid, evenin future reproductive bouts. The decrease in male investmentin eggs of low-diet females does not conflict with the contentionthat relative parental investment controls male intrasexualcompetition because, in mate-feeding species, male investmentinfluencing this competition includes more than investment incurrent offspring; females should compete for males if courtshipgifts aid survival and later reproduction.     

Sperm transport after insemination in the Alpine newt (Triturus alpestris, Caudata, Salamandridae)

The goal of this study was to test if sperm transport to the spermathecae in the Alpine newt (Triturus alpestris) requires active co-operation of the female. Artificial insemination of anaesthetised female newts was conducted using spermatophores collected from courting males and with sperm duct contents collected from sacrificed males. Sperm was present in the spermathecae of 9 out of 10 females inseminated with the spermatophores but in only 1 out of 8 females inseminated with sperm duct contents. The females of both groups laid some eggs after insemination, and a portion of these eggs in group of females inseminated with spermatophores were fertilized. However, the number of eggs produced by the females was much lower than typical egg-production in newts. The presence of sperm in the spermathecae of females inseminated with spermatophores and lack of sperm in the spermathecae of females inseminated with sperm duct contents suggests that sperm transport is either induced by the substances present in spermatophores and/or that sperm from the sperm duct is not fully mobile in comparison with sperm from the spermatophores.     

Male reproductive system of the arrow crab Stenorhynchus seticornis (Inachoididae)

Our aim was to describe the reproductive system of males and the formation of sperm packages in the seminal receptacle (SR) of recently mated females of the arrow crab Stenorhynchus seticornis. The male reproductive system was analyzed, and was described using light microscopy and histological and histochemical methods. The first pair of gonopods was described by means of scanning electron microscopy. Additionally, the dehiscence of spermatophores was tested using samples obtained from the vas deferens of males and from the seminal receptacle of recently mated females. Testes were tubular type, and each vas deferens consisted of three regions: the anterior vas deferens (AVD), including a proximal portion that was filled with free spermatozoa and a distal portion contained developing spermatophores; the median vas deferens (MVD) that contained completely formed spermatophores; and the posterior vas deferens (PVD), which contained only granular secretions. The accessory gland, which was filled with secretions, was located in the transition region between the MVD and the PVD. The spermatophores from the MVD were of different sizes, and none of them showed dehiscence in seawater, whereas those spermatophores in contact with the seminal receptacle were immediately broken. The ultrastructure of the gonopods revealed the presence of denticles at the distal portion, which contribute to the mechanical rupture of the spermatophore wall during the transfer of sperm. The contents of the PVD and accessory gland of males are transferred together with the spermatophores, and are responsible for the secretions observed among the sperm packets in the SR of the female. We suggest that these secretions formed the layers found in the SR of recently mated females, and may play a role in sperm competition in arrow crabs.     

Haltung und Zucht der Geißelspinne (Damon variegatus) (Phrynichidae) (Chelicerata: Amblypygi)

In the temporary carboniferous hall of „GONDWANA - Das Prähistorium“ in Germany, whip spiders (Damon variegatus) were kept and bred. 3,3 were purchased from a dealer in summer 2007. The night active spiders were kept together in a terrarium. No aggresions were observed. The animals were fed little locusts, young hissing cockroaches, and crickets. In 2008 courtship display and mating could be observed. The biggest male was the only active one. After 7 days after the intake of the spermatophores all females carried eggsacs under the ophistosoma. Each egg sack contained approximately 25-30 eggs. During the carrying phase only one female feasted on a cricket. 98 days after the egg sack was produced the young spiderlings hatched. The coloration of the spiderlings was completely different from the coloration of the adults. The spiderlings were carried by the female for the next 9 days. Then, the spiderlings moulted and left the female immediately. The adults were now separated from their young. The three groups of spiderlings stayed together in a smaller terrarium. However, each group from each female stayed separate from the others for weeks. The second moulting took place 41 days after the first one. No cannibalism was observed. Obviously Damon variegatus seems to be a spider with a social touch. If the terrarium and the climate conditions inside are adapted to the needs of the whip spiders keeping and breeding is possible. The species is highly attractive to visitors.     

回放雄虫第二种鸣声对稻褐飞虱生殖过程的抑制作用

结果表明：1. 回放稻褐飞虱雄虫第二种鸣声 (SMVS) 1～12 h可以显著降低雌雄虫的成功交配率,而回放SMVS 24 h则对此无明显影响;2. 回放SMVS对交配率的影响主要在于对试虫相遇前的求偶过程,表现为雌虫鸣叫率显著下降,对雄虫求偶声 (FMVS) 的反应延迟;雄虫对雌虫求偶声 (FVS) 的反应程度有所降低;雌雄虫的相遇前期显著延长;3. 回放SMVS不影响交配试虫的授精率和产卵量,但影响授精的质量, 表现在精包明显变小,卵的发育率下降。     

Male size,mating potential and lifetime reproductive success in the field cricket,Gryllus bimaculatus (De Geer)

Male size is known to influence short-term, competitive mating success in the field cricket, Gryllus bimaculatus. Short-term measures of mating success are, however, potentially misleading when considering the influence of sexual selection on male morphology and behaviour. The lifetime mating success of males was investigated in the absence of competition to determine the effects of male size per se on reproductive potential and any effects of female behaviour on male lifetime mating success. The cost of spermatophore production was relatively greater for small males who consequently had a longer refractory period between matings, thus limiting their reproductive potential. Large males had a mating advantage resulting from a differential response of females to the courtship attempts of large and small males. Furthermore, small males were ‘sexually incompetent’ in terms of their ability to attach spermatophores once mounted. There was, therefore, an overall positive relationship between male size and lifetime reproductive success.     

Reproduction of spined loach, Cobitis taenia, (Cypriniformes; Cobitidae) under laboratory conditions

A simple and reliable method is described for breeding spined loach, Cobitis taenia Linnaeus, 1758, under laboratory conditions. Three 40 L aquaria were each provided with a thick tuft of moss placed on top of a gauze-covered plastic box to serve as a spawning site. Ovoposition always occurred in the most densely available vegetation. The nonadhesive eggs fell through the gauze into the box. The spined loach is a fractional spawner releasing eggs in 14–18 batches at intervals of 2–23 (median 6) days. The total number of eggs per female was 2905–4282 during the reproductive season of 101–120 days. Yolks measured 1.14 ± 0.07 mm and eggs were 2.54 ± 0.22 mm in diameter. Total larval length was 5.03 ± 0.34 mm at hatching and 6.77 ± 0.34 mm at the beginning of exogenous feeding. The method allowed the rearing of numerous young for conservation measures and experimental investigations.     

Effects of carbaryl and cyhexatin on survival and reproductive behaviour of Cydia pomonella (Lepidoptera: Tortricidae)

The effects of carbaryl, an insecticide and an abscission agent, and cyhexatin, an acaricide, on the survival, reproductive behaviour and subsequent egg hatch and larval migration of the codling moth, Cydia pomonella L., were investigated under laboratory conditions. Dilution series starting with the concentration recommended for high volume application in the field were evenly sprayed in plastic cups. Depending on the concentration used, both pesticides resulted in high adult mortality, males being more susceptible. Although the total number of the eggs laid by C. pomonella females was significantly reduced in most treatments, the females exposed to different residues of carbaryl laid significantly more eggs during the first 24 h of exposure. This was not the case for cyhexatin. While in all treatments almost 50% of the eggs were laid on the side of the cups, the spatial distribution of the eggs laid under the lid and on the floor was concentration dependent. With one exception, continuous exposure of the moths to carbaryl significantly reduced the number of spermatophores per female. Less than one spermatophore per female was transferred at the highest four concentrations of carbaryl and the highest three concentrations of cyhexatin; whereas, the number of spermatophores per female amounted to about four per female for the other treatments. In contrast to carbaryl, which exhibited a high ovicidal effect at all concentrations, the ovicidal activity of cyhexatin was low. This was manifested in a high rate of egg hatch and the extent of embryonic development in most of the treatments. Furthermore, while carbaryl killed the newly-hatched larvae at all concentrations, cyhexatin acted as a larvicide at the highest two concentrations only.     

COURTSHIP FEEDING AND THE FITNESS OF FEMALE KATYDIDS (ORTHOPTERA: TETTIGONIIDAE)

Katydid males (Requena verticalis) produce spermatophores with a large sperm-free spermatophylax, which is eaten by the female after mating. In this study, I asked 1) how do spermatophylax nutrients affect the fitness of the mated female and her progeny? 2) does this male-produced food substitute for other food in the diet of the female, or is it a source of specialized nutrients? and 3) does an increase in the size of the spermatophylax eaten influence female reproduction in the same way as the additional spermatophylaxes that would be obtained from multiple mating? An experimental increase either in dietary protein or the number of spermatophylaxes eaten increased the number of eggs produced. However, spermatophylax size had no effect on egg number. An increase in either the size or number of spermatophylaxes eaten resulted in an increase in egg size. There was no influence of protein in the general diet on egg size. This suggests that males provide nutrition not available from other sources. Although there were no direct effects of number of spermatophylaxes eaten by females on the overwintering survival of their progeny, offspring from females producing larger eggs had a relatively higher probability of surviving winter. The amount of spermatophylax eaten had no influence on the mean adult size of progeny but significantly increased the mean date at which sons matured to adulthood. There was no influence of dietary protein on these variables. Since maturation date is positively correlated with adult size in both sexes, it is suggested that the influence of courtship feeding on maturation date may result in an increase in adult size and thus the fitness of sons. A significant correlation between the size of the female and the mean size of her sons (but not daughters) suggests that there is also a heritable component to body size.     

Sexual dimorphism, female reproduction and egg incubation in the oriental leaf-toed gecko (Hemidactylus bowringii) from southern China

We studied sexual dimorphism, female reproduction and egg incubation of the oriental leaf-toed gecko (Hemidactylus bowringii) from a population in southern China. The largest male and female in our sample were 60 and 57 mm snout-vent length (SVL), respectively. Males are the larger sex; sexual dimorphism in head size and tail length (TL) is evident in juveniles and adults, with males having larger heads as well as longer tails than females. Oviposition occurred between late May and late July. Females switched from laying two eggs early in the breeding season to 1-2 eggs later in the season. Clutch mass and egg mass were both independent of female SVL, whereas relative clutch mass was negatively correlated with female SVL. The previous conclusion that female H. bowringii lay a single clutch of eggs per breeding season is unlikely to be true. Thermal environments experienced by H. bowringii eggs affect incubation length as well as morphological and locomotor phenotypes of hatchlings. Hatchlings from eggs incubated at 30 degrees C were larger (SVL, tail length and body mass) and performed better in the racetrack than their counterparts from eggs incubated at 24 degrees C. Temperatures suitable for embryonic development are relatively high in H. bowringii, primarily as a consequence of the adaptive response to warm environments in southern China.     

Receptivity of female Neohelice granulata (Brachyura, Varunidae): different strategies to maximize their reproductive success in contrasting habitats

The extent of the receptive period may determine the mating strategies employed by female crabs to obtain mates. Here, we studied the receptivity of female Neohelice granulata (Dana, 1851) in the laboratory, including the form of the vulvae and the anatomy of the seminal receptacle (SR). We examined the factors that influence the duration of receptivity by comparing two populations inhabiting contrasting habitats: Mar Chiquita Coastal lagoon (MCL), which is an oligo-polyhaline estuary, and San Antonio Oeste (SAO), which is an eu-hyperhaline marine bay. Non-receptive females have immobile vulva opercula, while receptive females have mobile opercula. Histological sections of the SR showed that the degree of epithelium secretions was associated with the receptive stage of females, and they may be involved in the maintenance of viable sperm and in the dehiscence of spermatophores. The existence of a special tissue at the junction of the oviduct and the SR was described and proposed as an internal mechanism influencing the timing of ovulation. The duration of receptivity was dependent on the SR load and the capacity to lay eggs. Thus, females with empty SR exhibited longer receptivity and did not lay eggs, while those with full SR exhibited shorter receptivity and always laid eggs. Interpopulation differences showed that females from SAO had shorter receptivity and heavier SR and laid eggs more frequently than females from MCL. Based on our results, we suggest that N. granulata females can adjust the duration of their receptivity and control the moment of fertilization according to different internal mechanisms related to the morphology of the vulvae, the fullness of the SR and anatomical attributes of the SR. An important consequence of this control is greater sperm competition. The extent of the receptive period and the number of times that a female could become receptive in a single reproductive season may also depend on the habitat characteristics.     

Sexual Interference in the Sword-tailed Newt,Cynops ensicauda popei (Amphibia: Salamandridae)

This paper describes competitive interaction between males of the salamandrid Cynops ensicauda popei. The sexual behaviour of the male is influenced by the presence of a second, rival, male. Competition for access to the female and other male interactions continuously interrupt ongoing courtships. Spermatophore pick-up success is lower than in encounters involving single pairs. During triad encounters, fewer spermatophores were deposited than in dyad encounters, due to interference during the creep stage of courtship. Two basic forms of male sexual interference were distinguished: ‘lure away’ during the creeping stage, from a position that is different from the direction of creep; and ‘female mimicry’, during which the male presses his snout alternately against the courting male's tail and the female's snout. In both forms, a rival male may shove one of the courting individuals away. The repertoire of sexual behaviour patterns of Cynops ensicauda popei appears to be less complex and varied than that of most Triturus species. The courtship of Cynops places less emphasis on display behaviour with tail and body, and a stronger emphasis on the creeping stage, where the male carefully leads the responsive female over a series of spermatophores, but during which rival males may interfere in a variety of ways.     

Pelagic spawning of the hawkfish Oxycirrhites typus (Cirrhitidae)

Synopsis Pelagic spawning of the deep slope coral-dwelling cirrhitid Oxycirrhites typus was observed for two social groups at Papua New Guinea. This species was previously reported to be a demersal spawner in an aquarium. Courtship in social groups consisting of a single male and one or two females commenced just prior to or after sunset among the branches of gorgonian or antipatharian corals. Males and females occupied separate corals; males either visited females at their corals or met them at an adjacent coral just prior to courtship. Courtship was sequential and consisted of two or more bouts with each female that culminated in a rapid ascent into the water column and the release of floating eggs. Fertilized eggs, taken from a third social group, were spherical and averaged 0.69 mm in diameter. Spawning pairs sought refuge in their resident corals or in the coral where courtship occurred immediately after spawning was completed.