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1.
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   

2.
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   

3.
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   

4.
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   

5.
《Journal of Natural History》2012,46(6):1549-1571
Danielssenia intermedia Wells 1965, originally described from a single male specimen from the Fladen ground in the North Sea, is redescribed on the basis of new material of both sexes from off Cullercoats, also in the North Sea. Although D, intermedia has many similarities to the genera Danielssenia Boeck and Psammis Sars, it must be placed in a new genus Fladenia based on distinctive features of the female antennule, the mandible, maxilliped, first and fifth legs and the sexual dimorphism of both rami of legs 2–4. The characteristics of Fladenia are such that it serves to link the other genera of the danielsseniid complex with Paranannopus Lang. The proposal that all these genera should be placed in the family Paranannopidae Por is reinforced by close similarities in the structure of the female genital field.  相似文献   

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9.
Tanais dulongii (Audouin, 1826) is a small benthic crustacean with separate sexes and a marked sexual dimorphism characterized by a cephalothorax narrowed anteriorly, larger chelae (claws) and a pair of tiny genital cones in males, and ovisacs that form chambers for carrying embryos in females. Recent studies have described the existence of intersexual individuals with a cephalothorax similar to males, large chelae and ovisacs, but, due to their small size, it has not been possible to confirm the presence of genital cones under normal light microscopy. The present study analyses and compares external reproductive structures under scanning electron microscopy, of male and female T. dulongii, to corroborate the presence of both ovisacs and genital cones in potentially intersex individuals. The possible causes, such as hermaphroditism, environmental sex determination, parasitism, genetic aberration or endocrine-disrupting pollutants, are discussed.  相似文献   

10.
《Journal of Natural History》2012,46(27):2483-2514
A faunistic survey of the deep‐sea hyperbenthic copepods in the Sulu Sea, which has a deep basin and is connected via shallow straits with the Pacific and the South China Sea, was carried out in November and December 2002, using beam trawls and a mid‐water trawl. Two new genera and four new species of the primitive calanoid family Arietellidae are described. A new genus Metacalanalis shows intermediate characteristics between those of Metacalanus Cleve, 1901 and Pilarella Alvarez, . Another new genus, Protoparamisophria, is closely related to Paramisophria Scott, 1897, but exhibits more plesiomorphic states in the female genital system and appendages. Two new species of the genera Paraugaptiloides Ohtsuka, Boxshall and Roe, and Sarsarietellus Campaner, 1984 are the second and the third species, respectively, for these genera. This discovery enhances the validity of these rare genera, and sheds light on the geological history of the Sulu Sea and the evolution of the Arietellidae within it.  相似文献   

11.
《Journal of Natural History》2012,46(13-16):731-750
Three new species of rare benthopelagic clausocalanoidean genera with sensory setae on the maxilla are described from female specimens collected during the German Antarctic expeditions ANDEEP I–III in 2002 and 2005, mainly from abyssal depths close to the sea bed. Brodskius abyssalis sp. nov. differs from congeners by the lack of rostral filaments, two setae on the second segment of antenna exopod, thread‐like tips of maxillary worm‐like sensory setae, and the length of spines of P5 exopod. Rythabis assymmetrica sp. nov. is distinguished from other species in the genus by asymmetrical posterior corners of the prosome, the shape of spermathecae, and setal numbers on the maxillulary distal basal endite plus endopod. Omorius curvispinus sp. nov. is characterized by strongly curved setae of the maxillipedal syncoxa, a comparatively long seta on the basis of antenna, a slightly swollen genital double‐somite, and the shape of spermathecae. The genera Brodskius, Omorius, and Rythabis are recorded for the first time from the southern hemisphere.  相似文献   

12.
I present an update on the taxonomy of the filistatid genera Wandella Gray and Yardiella Gray, both endemic to Australia. Two new species are described: Wandella grayi sp. nov., known from Queensland, and Wandella infernalis sp. nov., known from a single cave in Western Australia. The male of Wandella australiensis (L. Koch) and the females of Wandella stuartensis Gray and Wandella waldockae Gray are described and illustrated for the first time. New records are given for these and other species of Australian filistatids, including the first epigeal records of Yardiella humphreysi Gray, a species so far known only from caves. Updated distribution maps are presented. Additionally, I present novel morphological data for Wandella using light and scanning electron microscopy. The cephalothorax, spinning organs, genitalia and appendages of some species are illustrated in detail. I report the presence of a putative claw extensor muscle in the male palpal cymbium, and describe interesting modifications in the clypeal region of adult males. The phylogenetic significance of these characters is briefly discussed.  相似文献   

13.
Observations on the behaviour and chosen environment are reported of the zygopine weevils Mecopus audinetii, M. bispinosus, M. fausti, M. pulvereus, Phylaitis v-alba and Osphilia sp. Mecopus audinetii and M. bispinosus were not distinguished in the field, but can be separated by details of the male and female genitalia and by the presence in the male of M. bispinosus of long black hairs on the pronotum. All the species studied were found on the bark of fallen or dying trees, the Mecopus species and Phylaitis v-alba being associated with whitish-silvery bark and the Osphilia species with greenish-brown substrates. The small Phylaitis species was found on branches of smaller diameter than those frequented by the larger Mecopus species. All the species are fairly cryptic in coloration, but when moving the larger species are more visible than the smaller, and the ones on pale bark are more visible than those on greenish-brown bark. Potential predators may be confused by jerky movement patterns observed in all species and the distant shadows cast by the long-legged larger Mecopus. The weevils are not believed to be involved in any mimicry, although this has been suggested for other members of the same subfamily. A single contest between males of Mecopus audinetii/bispinosus was observed, in the absence of a female. Each male attempted to dislodge its opponent from the substrate using its rostrum; the thoracic spines were not seen to be used. Contests between males of Osphilia sp. and Phylaitis v-alba were observed in the presence of females of the appropriate species. The males of Osphilia species attempted to dislodge one another from the back of the female in contention, and also engaged in a spiralling flight together. The males of Phylaitis v-alba did not come into physical contact, but responded to the threat of an approach. During copulation in Mecopus audinetii/bispinosus and Osphilia sp. the male repeatedly brushed the head and thorax of the female with his front legs. In the first species the male stood on the substrate and ‘caged’ the female with his legs and rostrum but in the second the male, ‘rode’ the female. Both species oviposit into the bark of their trees, the females using the rostrum to drill a hole for the ovipositor. The length of the rostrum probably determines the thickness of the bark through which eggs are laid, and hence the area of the region of the tree inhabited by the beetles.  相似文献   

14.
《Journal of Natural History》2012,46(21):2615-2626
Based on external structural features, especially those of the mouthparts, and male and female genitalia, the aleocharine staphylinid genus Leptandria, new genus, is proposed and diagnosed. Three new species are also described, L. ashei, L. tishechkini and L. ecitophila, with a key to differentiate them and numerous illustrations of diagnostic features presented.  相似文献   

15.
Summary

The reproductive organs of the male and female Gryllodes sigillatus, together with their associated muscles, are described in detail. The male reproductive organs are characterized by the presence of the accessory gland tubules and the absence of sperm vesicles. The presence of a pair of lateral pouches on the genital chamber and a chitinous bursa copulatrix at the posterior end of the spermathecal duct are peculiar features of the female reproductive organs. The testes and the ovaries are attached by the testicular and ovariolar ligaments respectively to the tergum of the first abdominal segment.  相似文献   

16.
《Journal of Natural History》2012,46(25-26):1793-1804
The eumaeine hairstreak species Thecloxurina tegulina Bálint and Boyer, sp. n. from SW Peru, department Apurímac (type locality: Karkatera, NW of Ampay, 3,200 m, 13°34′286″S; 72°58′501″W) is described on the basis of qualitative and quantitative wing pattern, male genital and spectral characters. The spectral reflectance of the closely related genera Penaincisalia and Thecloxurina are investigated and compared. It is demonstrated that the spectral characteristics of the two genera are qualitatively differing, and the taxa investigated representing the two genera (Penaincisalia:Thecloxurina = 3:5) also have characteristic species dependent reflectance peaks measured at normal incidence.  相似文献   

17.
Summary

A gynandromorph of Austrosimulium (Austrosimulium) australense (Schiner) is described. This individual had the head of a female, whereas the thorax and abdomen were a mosaic of male and female characters. The genitalia of both sexes were present, but only the female set was complete. Overall, the female characters of this specimen appeared to be more fully expressed than those of the male.  相似文献   

18.
19.
《Journal of Natural History》2012,46(9-10):615-624
Two new species of Porphyrochroa Melander are described from Paraná, Porphyrochroa atlantica and Porphyrochroa sierra. A new record is also made for Porphyrochroa pacaraima Mendonça, Rafael and Ale-Rocha, from Mato Grosso state. Drawings of the male genitalia are provided. A key to Brazilian species from southern and south-eastern Brazil is presented.  相似文献   

20.
The Schizopodidae (formerly subfamily Schizopodinae, family Buprestidae) is elevated to family status, based on a review of its morphology including wing venation, male and female genitalia, larvae, and also a cladistic analysis of in-group and out-group comparisions. Two tribes are recognized: Schizopodini LeConte with one genus, Schizopus LeConte and Dystaxiini Théry with two genera: Dystaxia LeConte and Glyptoscelimorpha Horn. The genus Schizopus contains two species: S. laetus LeConte and S. sallei Horn with one new subspecies, S. sallei nigricans Nelson. The genus Dystaxia includes two species: D. murrayi LeConte, and D. elegans Fall. The genus Glyptoscelimorpha is separated into two subgenera: G. (s. str.) with two species, G. marmorata Horn, and G. viridis Chamberlin; and G. (Dystaxiella) Knull, new status, with one species, G. (D.) juniperae (Knull), new combination, with a new subspecies, G. (D.) juniperae viridiceps Nelson. All taxa are described and information on variation, type localities, distribution, biology, and comparisons are given for each species. Keys to taxa for tribes to subspecies are provided. Illustrations for all species, including habitus, male and female genitalia and other parts, as well as cladograms of relationships are presented. Lectotypes are designated for the following: Yermoella helferi Obenberger, Dystaxia elegans Fall and Glyptoscelimorpha marmorata Horn. Tables of taxa, characters and character states used in the cladistic analysis are included.  相似文献   

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