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1.
Males in six of seven species of Phyllophaga perform apparent courtship behaviour during copulation. As predicted by the hypothesis that such copulatory courtship is under sexual selection by female choice, behavioural details differ between species. The modified male abdominal sternites, which rub against the female's pygidium during copulation and whose morphology also differs between species, and the flattened, setose tarsi of males of one species probably function as contact courtship devices during copulatory courtship. Observations of events inside copulating beetles were made through the semi-transparent abdominal sternites of females and male genitalia in three species. They revealed cryptic genitalic thrusting behaviour of male genitalia within the female which occurred even when there was little or no external movement of the male genitalia. Dissections of pairs frozen in copula demonstrated that males transfer large quantities of material to females during copulation that is not physically related to sperm transfer. The type of material varied between species. In at least two species most of the transfer apparently occurred after sperm transfer. The possibility that some male genitalic structures function as holdfasts and/or stimulatory devices was suggested by their positions relative to female structures, and/or their movements within the female. Portions of male genitalia with strong bristles tended to lie against setose or more heavily sclerotized portions of the female reproductive duct. Some portions of female genitalia which vary between species seem ill-designed to exclude the genitalia of cross-specific males. The female reproductive tract is partially everted during copulation in one species.  相似文献   

2.
Summary

Heptacarpus pictus, a small caridean shrimp inhabiting the low intertidal of southern and Baja California, breeds during the winter, spring, and summer months. Fall is a period of growth. Life span of an individual does not exceed 18 months, with fish predation as the most likely source of mortality.

Females are multiple brooders, carrying developing embryos concomitant with increase in ovary size. Hatching of larvae is followed by a moult, after which the female is attractive to males and receptive to copulation. A distance pheromone does not appear to be involved in attraction of males to females. Males apparently respond to a non-diffusible substance on the exoskeleton of newly moulted females.

Precopulatory behaviour is absent. Copulation can be divided into a series of relatively stereotyped events. Female rejection of the male or his spermatophore is the chief cause of unsuccessful matings.

Males deposit the spermatophore on the underside of the female's first abdominal segment. Sperm packets are formed upon extrusion from the male's genital openings, and are composed of a mucoid material in which sperm are mixed. The glutinous spermatophores adhere to the female's smooth abdominal sternite.

The endopods of pleopods 1 and 2 of the male are different in shape, size and setation from homologous rami of females and juveniles. Endopods of pleopod 1 possess a distally located appendix interna, absent in juveniles and females. An anteriorly projecting process, the appendix masculina, is located on the endopod of pleopod 2 in males. Experiments were performed which showed that these modifications insure proper deposition of spermatophores. Males which had the copulatory rami removed did not transfer spermatophores as successfully as normal males.

Transfer of the spermatophore from the male to the female is a result of the interplay of male pleopods 1 and 2 during copulation. The large expanded abdominal pleurae of females prevent the male's genital opening from contacting her abdominal sternite. Thus, the male's anterior pleopods have become modified to lift the emitted spermatophore from his genital orifices to the first abdominal sternite of the female.  相似文献   

3.
《Journal of Natural History》2012,46(19-20):1189-1202
Allocosa alticeps and Allocosa brasiliensis are two sex-role-reversed spiders. Females locate males and initiate courtship. Copulation occurs inside male burrows and after copulation the males deliver their burrows to the females. We explored the occurrence of differences in morphological traits related to sex roles in both Allocosa species and compared the results with two non-burrowing wolf spiders with typical sex roles. We measured the length of the foreleg's tibia-patella and the chelicerae. Scanning electron micrographs of palpal tarsus distal sections were taken. Males showed higher values than females in all the traits considered. Adult and penultimate males lacked true claws compared with juveniles and females, but showed modified spines. The palpal organ was more proximal to the tibia compared with the non-burrowing lycosids considered in this study. Spines and palpal organ location could be associated with more effective digging. We discuss how natural and sexual selection could interact on morphology in this scenario.  相似文献   

4.
While expulsion of male ejaculates by the females after copulation has been reported for various animal groups, expulsion followed by consumption of the expelled ejaculate is a rare behaviour outside spermatophylax-producing orthopterans. Among Diptera, this behaviour has been reported for a few species of Piophilidae, Empididae and Ulidiidae. Here we report on its occurrence among Euxesta eluta and Euxesta mazorca (Diptera: Ulidiidae). We also attempt to characterize the mating system of E. eluta in order to facilitate future hypothesis testing to understand the behavioural factors leading to the evolution of this peculiar behaviour. For this, courtship sequences, copulation duration, frequency of ejaculate expulsion and subsequent consumption, and latency to ejaculate expulsion for both E. eluta and E. mazorca were recorded. The time of sexual maturation, the time window of sexual receptivity during the day, and the mating frequency and variance in mating success for males and females (degree of polygamy) were determined for E. eluta. Both E. eluta and E. mazorca males engaged in elaborate courtship sequences involving visual and tactile displays before copulation. Females of both species almost invariably expelled and consumed ejaculates after copulation. Female E. eluta, required a 6- to 9-day period feeding on protein and sugar before becoming sexually receptive. Reproductive activity occurred continuously over the day with an early morning and late afternoon peak. Both males and females could mate multiply, with multiple partners over a 2-h observational period. Sexual network analysis revealed that some males and females had greater mating success than others. Ejaculate consumption appears to be widespread in the genus Euxesta. It is possible that females obtain nutrients from this behaviour while exerting some control over egg fertilization.  相似文献   

5.
《Journal of Natural History》2012,46(8):1639-1659
Males of Tidarren cuneolatum (Tullgren, 1910) amputate one of their palps a few hours after the penultimate moult, like T. sisyphoides (Walckenaer, 1841) from the USA (Branch, 1942). Hence adult males, which are minute, have only one palp, either left or right randomly. This palpal organ is not oversized, when compared with other small spiders. During courtship females are unusually active, signalling receptivity by continuous twanging with legs II. Males construct a mating thread. Copulation involves one insertion, which lasts ca 4 min. Thus, only one receptaculum is inseminated during copulation. With the advance of insertion the male's prosoma becomes shrunken. Copulation regularly ends in mate consumption. In copulation with a virgin female the palp was inserted contralaterally. Females taken in the field had both receptacula filled with sperm and therefore were polyandrous. Re-mating was also observed in the laboratory. Remarkably the second male performed an ipsilateral insertion, if it possessed the same palp as the previous male. Probably the virgin receptaculum was recognized. Postembryonic development is rapid in males, which moult three times and mature ca 41 days after hatching from the cocoon. Females need four or five moults and ca 69 days to reach maturity and then survive ca 2-4 months.  相似文献   

6.
Antennation can play several roles in hymenopteran copulation, mainly in wasps. The digger wasp Sphex ingens Smith has a very peculiar sexual behaviour, in which forced copulation is a striking element. However, communication through antennation during the pre-copulation and copulation phases and the relationship between the sexual performance of males and the final result of copulation require further clarification. The sexual behaviour of wild populations of S. ingens was filmed during the breeding season in a site between the beaches Meros and Aventureiro, Ilha Grande, southeastern Brazil. We assessed antennation behaviour, courtship duration, sexual performance, and genital clasping. Only successful males had the genital clasping assessed. Evidence found so far points out that the successful males showed better sexual performance – that is, they antennated more in a shorter courtship duration. Also, genital clasping in successful males did not depend on antennation, courtship duration, or sexual performance. Our results shed light on some aspects of the sexual behaviour of wasps, as they explain part of the sexual selection mechanisms adopted by the species.  相似文献   

7.
《Journal of Natural History》2012,46(14):1639-1660
Three new species of Pseudohaliotrema Yamaguti, 1953 were collected from two Siganus species caught off Singapore. They are Pseudohaliotrema virgata n. sp. and P. molnari n. sp. from Siganus virgatus and P. falcata n. sp. from S. guttatus. They differ in the shape and size of both the body and haptoral sclerites and in the morphology of the male organ (modified copulatory organ). Pseudohaliotrema species from siganids are characterized by having a large prominent vaginal pouch, an eversible spermatophore transfer tube associated with the vaginal pouch, ovoid spermatophores (in mature worms), a male organ adapted for spermatophore formation, a large prostatic reservoir, and a testis and ovary arranged side by side. Pseudohaliotrema plectocirra Paperna, 1972 is re-assigned as Tetrancistrum plectocirra (Paperna, 1972) n. comb. Pseudohaliotrema species from non-siganid fish do not possess these characteristics and belong elsewhere. The generic diagnosis of Pseudohaliotrema is amended. Pseudohaliotrema species use a spermatophore for sperm transfer, which is documented in detail for P. virgata n. sp. The same reproductive strategy is used by P. molnari n. sp. and P. falcata n. sp., as indicated by the presence of spermatophores on the spermatophore transfer tube and inside the vaginal pouch. The presence of individuals exchanging spermatophores indicates that P. sphincteroporus Yamaguti, 1953 and P. sigani Yamaguti, 1953 also employ the same mechanism. The spermatophore, assembled in the sclerotized male organ and stored in the spermatophore chamber, is retrieved by the eversible spermatophore transfer tube (housed within the vaginal pouch) and drawn into the vaginal pouch as the spermatophore transfer tube invaginates. Within the vaginal pouch, the wall of the spermatophore disintegrates releasing spermatozoa.  相似文献   

8.
Several Caucasian rock lizards of the genus Darevskia of hybrid origin are known to reproduce parthenogenetically. Local communities can be composed exclusively of parthenogens, though syntopy with bisexual members of the genus may occur. In some localities, reproduction between bisexual and parthenogenetic Darevskia has been previously reported based on lizard intermediate morphology and karyology (3n, 4n). However, the frequency of such heterospecific matings remains unknown. We indirectly quantified the reproductive interactions through the inspection of copulation marks in females in a mixed Darevskia community from Kuchak (Armenia) composed of two hybrid parthenogens (D. armeniaca and D. unisexualis), one bisexual species (D. valentini) and their putative backcrosses. A total of 139 adults were randomly collected and photographed. Females were later measured (SVL), inspected for inguinal marks and ranked from 0 (no scars) to 3 (≥ 3 scars). The lizard species and ploidy determination was ensured by a parallel microsatellite analysis. Sex-ratio in the community was extremely biased due to the high abundance of parthenogenetic females. All female types displayed copulation marks with frequencies varying from 80% in D. valentini to 64% in D. armeniaca. Remarkably, 7 out of 11 (64%) backcross females also showed marks. In the most abundant D. armeniaca, the prevalence and intensity of copulation marks increased with body size, just as predicted for polygynous female lacertids. These results indicate that copulation between parthenogenetic and bisexual species in Darevskia mixed communities is common and driven by sexual selection, thus reinforcing previous suggestions of reproductive interaction in syntopy. Evolutionary implications of these findings are discussed.  相似文献   

9.
Summary

The intra-specific mating behaviour of two closely related sympatric staphylinid beetles, Philonthus cephalotes (Grav.) and P. sordidus (Grav.) is described in detail. Mating is essentially similar in the two species, although differing in the duration of copulation (1·7 min in cephalotes, 44·6 min in sordidus), and consists of four phases (A)-(D); (A) pre-copulatory phase, (1) examination of female abdominal apex by male, (2) examination of male abdominal apex by female, (3) prolonged examination of female by male, (4) mounting by male (5) extrusion of male genitalia; (B) copulatory phase; (C) terminal phase; and (D) post-copulatory phase.

An attempt to test the role of species specific patterns of peg setae, occurring on the genitalia of males, as a tactile signalling system was made by observation of inter-specific interactions between males and females of the two species. Under the trial conditions inter-specific intromission did not occur and behaviour was predominantly aggressive. Evidence suggests that signals during the early stages of an encounter between the sexes of different species are generally sufficient to deter further courtship. In two instances courtship reached a more advanced stage and here the patterns of peg setae on the male genitalia may have come into play, operating as a signalling device.  相似文献   

10.
《Journal of Natural History》2012,46(33-34):2117-2129
A new species of Mesabolivar is described from Brazilian forests: Mesabolivar delclaroi. The mating behaviour, postembryonic development, number of egg sacs and eggs, birth rate, number of instars, developmental time until adulthood, sex ratio and size of cephalothorax (per instar) were recorded. The sexual behaviour was described and categorized into four steps: courtship, pre-copulation, copulation and post-copulation. After hatching, individuals presented five instars until maturity. The mean number of eggs (42 ± 16.6) and live births (31.5 ± 3.4) of the first egg sac were significantly greater than that of a second one (23.8 ± 3.8, and 19.25 ± 3.9, respectively). The developmental time from birth to adulthood (130.8 ± 9.6 days) did not differ significantly between egg sacs produced (128.61 ± 11.1). The size of the cephalothorax did not differ among adults or between sexes. The sex ratio revealed a shift in favour of females (4: 3).  相似文献   

11.
A total of 22 Indonesian and Japanese species of epilachnine ladybird beetles were divided into the following three groups on the basis of the conditions of bursa copulatrix and spermatheca, and modes of sperm transfer. Group 1, ‘Henosepilachna’, being characterized by a spermatheca derived from the lateral side of a well developed bursa copulatrix and formation of a ‘spermatophore’ prior to ejaculation; group 2, Epilachna admirabilis species-group and E. chapini group, by a spermatheca derived from terminal end of a well developed bursa copulatrix and lack of spermatophore formation; and group 3, E. flavicollis group and E. fallax group, by a reduced bursa copulatrix with or without a terminally positioned spermatheca and lack of spermatophore formation. It was suggested that groups 2 and 3 are phylogenetically more closely related to each other than they are to group 1.  相似文献   

12.
《Journal of Natural History》2012,46(22):2035-2045
Observations on the courtship behaviour, mating behaviour and mating success of a leaf‐frog, Phyllomedusa rohdei, population were conducted in a temporary flooded site of the Atlantic Forest, south‐eastern Brazil. We did not find any influence of size and body weight on male mating success across three scales: seasonal, nightly chorus and local groups (males found within 1?m of a mated pair). In addition, no evidence was found that female Phyllomedusa rohdei exhibit overt mate choice. The formation of mated pairs in P. rohdei occurred because males moved toward the females, rather than reverse. The only variable that was significantly related to male mating success was the number of nights of participation in chorus activity. Besides calling tactics, males showed active searching behaviour. There was no evidence of size‐ and mass‐assortative mating, and a high percentage of fertilization at all size and mass ratios of males and females was observed. Clutches in this species are produced in the same manner found in others members of Phyllomedusa; a purse‐like nest is made over water by folding a leaf around the egg mass (embryos and fluid‐filled capsules). Finally, we supply a list of several studies that examined the relationship between size or mass ratios of males and females in amplexus and its influence on fertilization rate, and show that size‐assortative mating in anurans is inconsistent (present in some species but not in other).  相似文献   

13.
《Journal of Natural History》2012,46(1-2):107-117
Males of Conops quadrifasciata “claim” females in late morning and then spend the rest of the day exposed as “riders” to attacks by other males. Male riders can respond to an attack by performing an abdomen‐lift which denies the attacker access to the female's genitalia. Attacking males can tailor their behaviour to suit the prevailing conditions. If a rider is engaged in a “repeat” copulation (as he does at regular intervals), the attacker “waits” beside the rider. If the rider is not in genitalic contact with the female, the attacker tries to mate with her immediately. It is proposed that females deliberately expose their riders to takeovers in order to gain the fittest mate.  相似文献   

14.
《Journal of Natural History》2012,46(12):2241-2250
The sexual behaviour of a diurnally active cricket in the genus Nisitrus is described from observations made in its natural habitat. Courtship consists of both auditory and visual elements. The male transfers up to five spermatophores to an individual female during a single reproductive sequence lasting more than 3 h. Males guard females during the intervals between successive production of spermatophores. The visual signal-one or more hind-leg waves-given by the male to indicate to the female that she can eat the old spermatophore, and that a new one is now ready, appears to be unique among gryllids studied so far. Females are very co-operative, as they stand to receive and then eat as many as five spermatophores in relatively quick succession. Inter-male rivalry does not occur in the absence of females, but possible 'spoiling' behaviour may occasionally interrupt mating sequences.  相似文献   

15.
《Journal of Natural History》2012,46(23-24):1439-1452
We studied the breeding activities of Bokermannohyla nanuzae at an Atlantic Forest site in southeastern Brazil from August 2010 to April 2012. We described courtship behaviour, acoustic parameters of calls, egg clutch features and the egg-laying site, and characterized the reproductive mode. We recorded calling males and gravid females almost year-round, except for a few months in the dry season. We observed the interaction of five male–female pairs that exhibited stereotyped behavioural sequences including visual and tactile signals. We identified three different types of calls that we considered as the advertisement call and two types of courtship calls. Egg clutches were placed in rocky crevices with water or in streamside puddles, among rocks, that would be likely to be flooded as stream water level raises, which characterizes a reproductive mode different from the one previously recognized for this species. The breeding biology of B. nanuzae is complex, with elaborate courtship behaviour and signalling.  相似文献   

16.
Collections, observations and experiments were used to investigate the behavioural ecology of gall thrips (Thysanoptera: Phlaeothripidae) in New South Wales and Queensland, Australia. Data are presented on aspects of gall morphology, male and female morphology, behaviour, life cycles, and sex ratios for six gall-forming species, five species of inquilines (invaders that do not form galls), and one genus that uses secretions to glue phyllodes (modified petioles) together. During gall foundation on phyllodes of Acacia pendula, females of Kladothrips rugosus Froggatt fight other females to the death, males fight other males to the death, and one female or one adult of each sex remains alive within the gall to breed. In addition to the live adults, half of newly found galls contained dead bodies of from one to 13 males and females, which were apparently killed in fights. In Oncothrips tepperi Karny, which forms galls on Acacia oswaldii, single females found new galls, and females engage in lethal fighting during the period from gall initiation until closure. First-generation broods of Oncothrips tepperi comprise winged males and winged females with a sex ratio of about 1:6 female biased. Each gall also contains several wing-reduced adults with larger forelegs than winged adults, which probably either fight among themselves or defend their siblings from gall invaders. Adults of Oncothrips tepperi breed in the galls for two or more generations, whereas in all of the other species studied on Acacia only one generation occurs in a gall. Females of the inquiline Koptothrips flavicornis invade young, first-generation galls of Oncothrips tepperi, kill the foundling female, and produce their own offspring. Single females of Oncothrips antennatus (Moulton) form galls on Acacia aneura, and apparently do not fight. Winged females of Oncothrips antennatus have smaller forelegs, relative to their body size, than do winged females of Oncothrips tepperi. In Onychothrips arotrum Mound and Onychothrips tepperi (Uzel), single females from galls on Acacia aneura. In each species, females engage in lethal fighting during gall initiation. The sex ratio of Onychothrips arotrum broods is about 1:18 female biased. The inquiline Csirothrips watsoni Mound invades galls of Onychothrips arotrum, apparently after most or all of the offspring have left, and breeds inside. Females of this inquiline will kill live Onychothrips arotrum inside the galls, and they apparently plug gall entrances with cast O. arotrum exuviae. Iotatubothrips crozieri Mound and Crespi is involved in the formation of large, woody galls on stems of Casuarina, perhaps in association with a microorganism. They breed in these galls for many generations. Galls contain several to thousands of individuals, and the adult sex ratio is about 1:4 female biased. Adults of the inquilines Thaumatothrips froggatti and Phallothrips houstoni Mound and Crespi invade these galls, kill the Iotatubothrips adults, and breed therein. The Iotatubothrips occasionally attempt, ineffectually, to fight off the invaders, and they apparently make partitions within the gall to protect themselves from takeover. Adults of Lichanothrips spp. glue phyllodes of Acacia harpophylla together using eggs and patches of secretion, and they breed in the resultant narrow space. Xanothrips xantes Mound breed in these spaces after the Lichanothrips have left. Fighting in Kladothrips rugosus, Oncothrips tepperi and Onychothrips tepperi involves two adults rearing up head to head, sparring with their enlarged, armed forelegs raised, and attempting to grasp and hold their opponent with their forelegs and drive their sharply pointed fore-tarsal teeth into their opponent's body. Females of Onychothrips arotrum also grasp, stab and kill with their forelegs, but they have not been observed to rear up head to head. Three of the inquiline species, Csirothrips watsoni, Thaumatothrips froggatti and Phallothrips houstoni, kill the original gall inhabitants by extending their forelegs directly in front of their bodies, tilting their heads back, remaining in this position for variable periods of time, and sharply pulling their armed fore tibiae towards the fore femora when their victim is near. Inquilinism in gall thrips may have evolved from lethal intraspecific fighting. Certain aspects of behaviour and morphology in Australian gall thrips, such as high prevalence of lethal fighting, gall ‘plugging’ in Csirothrips watsoni, attempted gall defence and apparent formation of partitions in Iotatubothrips crozieri, and the presence of wing-reduced adults in Oncothrips tepperi, indicate that these species exhibit some of the most complex behaviour thus far discovered in Thysanoptera.  相似文献   

17.
During mating, males of Cressida cressida (Lepidoptera, Papilionidae) form a large external mating plug or sphragis that covers the female's copulatory opening and physically prevents remating. The sphragis has lateral and distal projections that make it an obvious structure. We tested experimentally the hypothesis that the sphragis acts as a signal of female mating status. Males pursue mated females with an intact sphragis only briefly and rarely make physical contact with them. When the sphragis of a mated female is removed or reduced in size, males are significantly more likely to physically contact the female and initiate the aerial takedown that preceeds a copulation attempt. These results suggest that the sphragis deters male sexual interest at a distance and thus functions as a signal of female mating status. The discussion focuses on the fitness consequences for females and their mates of the signal function of the sphragis.  相似文献   

18.
《Journal of Natural History》2012,46(35-36):2363-2371
Reproductive aspects of Ameerega braccata, a Cerrado endemic species of Dendrobatidae, were studied in the surroundings of the type locality of the species, Chapada dos Guimarães, mid-southern Mato Grosso State, Brazil. We found that males call mainly early in the morning and in the late afternoon. During courtship, the female approaches a calling male and tactile and visual communication occurs. Males call continuously while guiding females to the oviposition site, which may be situated as far as 24 m (in a straight line) from the initial encounter site. Spawn are deposited over fallen leaves on the soil surface or in burrows. Female snout–vent length and body mass did not explain the variation in ovary mass, or the variation in the number and size of post-vitellogenic oocytes. The results reported here for A. braccata might help to understand trends in the evolution of dendrobatids in open Cerrado environments.  相似文献   

19.
The reproduction and parasite associates of the squat lobster Munidopsis platirostris (A. Milne Edwards and Bouvier, 1894) were investigated based on collections made in the Bahamas and Curaçao with grassmat and bundled fishing net traps used to collect sipunculan worms and other small invertebrates. Size of ovigerous M. platirostris was significantly correlated with clutch size for females from both localities but females from the Bahamas produced significantly more eggs (on average 10.1 eggs/clutch) than females from Curaçao (on average 6.6 eggs/clutch). Early embryos of M. platirostris from the Bahamas were 0.74–0.82 mm in diameter, similar to some other species of Munidopsidae as well as Chirostylidae. Two species of crustaceans, another squat lobster and a leptostracan, as well as a limpet mollusc, were collected with M. platirostris in the Bahamas, while a sipunculan was an associated species in a Curaçao collection. One specimen of M. platirostris had an unidentified cryptoniscoid epicaridean isopod, possibly representing a new genus and species. Two specimens of M. platirostris each had one rhizocephalan externa of a species belonging to Lernaeodiscus Müller, 1862 but their morphology does not match that of L. schmitti Reinhard, 1950, the only species in the genus known from squat lobsters in the western Atlantic. Additional materials and tools, such as DNA analysis, are needed to describe these potentially new parasites and we suggest that use of these traps may be an effective method to obtain additional samples.  相似文献   

20.
《Journal of Natural History》2012,46(4):1015-1027
Males of many bees in the subfamily Nomiinae (Halictidae) have numerous secondary sexual characters, which provide much systematic information. Similarly, the use of these structures by males during sexual behaviour may provide useful characters, but the courtship and copulatory behaviour of most of these bees is not known. Structures and behaviour used for courtship and mating are described for two species of nomiine bees, Dieunomia heteropoda and Nomia tetrazonata, along with brief observations of mating in a parasitic bee, Triepeolus verbesinae (Apidae: Nomadinae). A review of mating behaviour within the Nomiinae shows no obvious phyletic patterns, based upon present limited knowledge. The species-specific nature of the male secondary sexual characters suggests they may have evolved in the context of sexual selection, but behavioural data from populations of additional species are needed to evaluate the hypothesis adequately.  相似文献   

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