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1.
In some butterfly species males attach a large external mating plug termed a sphragis to the female abdomen during mating. This is derived from male accessory secretions and covers the female ostium bursae and surrounding areas, thus preventing or delaying remating. Specimens of all 12 species of the genera Zerynthia, Allancastria and Bhutanitis (Lepidoptera: papilionidae), which form a natural clade within the Zerynthiini, were examined for presence or absence of a sphragis and their male and female genitalia were studied. In all three genera female genitalia lack a typical sinus vaginalis and the sterigma is modified to form an exposed, shiny, well-sclerotized genital plate, derived from the fusion and expansion of the lamellae ante- and postvaginales. The exposed ostium bursae is situated near the posterior end of the genital plate in Zerynthia, whereas in Allancastria and Bhutanitis it is near the anterior end. A crude irregularly formed sphragis was found at least facultatively in all species. The sphragides of Zerynthia and Bhutanitis were generally poorly developed, in most cases only partially covering the female genital plate. In Allancastria the sphragis mostly covered the genital plate entirely, and generally incorporated numerous long scales derived from the male’s 8th abdominal segment; scales were sometimes sparse or absent, probably due to depletion from repeated matings by males. In Zerynthia, males lacked the dense terminal abdominal tuft of elongated scales found in Allancastria, and their sphragis lacked scales. The sphragis of Bhutanitis thaidina incorporated scales from the male valves, whereas in the B. lidderdalii sphragis (and probably B. ludlowi) the scales derived from the male’s 8th abdominal segment. The role of the scales and possible reasons for the difference in the development of the sphragis among these genera are discussed.  相似文献   

2.
Two new species of the commensal shrimp genus Periclimenaeus Borradaile, found in the waters of the Maldive Islands, Indian Ocean, are described and illustrated. P. tchesunovi sp. nov. is related to P. rastrifer Bruce. The former may be distinguished by its deeper rostrum, with dentition 6/1, the presence of supraorbital tubercles, and broad, spatulate fingers on the first pereiopods. P. zarenkovi sp. nov. closely resembles P. diplosomatis Bruce in the presence of minute denticulations on the dactylar cutting edge of the major second pereiopod, but differs from it by a deeper rostrum with 5 dorsal teeth, more robust chelae of the second pereiopods, and small dorsal telson spines.  相似文献   

3.
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   

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(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   

6.
《Journal of Natural History》2012,46(33-34):2081-2094
The life cycle and population structure of Hemilepistus klugii were studied in a population in Varamin, Iran. The population was sampled monthly (or fortnightly during the breeding season) from February 2008 to June 2009 and a total of 7015 individuals, comprising 1069 males, 1079 females and 4867 juveniles, were collected. As in other Hemilepistus species, five distinct phenophases, namely pair formation, gestation, hatching, growth and stationary, were recorded during the life cycle of H. klugii. The overall sex ratio was 1 : 1 but varied over time. Ovigerous females were observed only in April, indicating a seasonal and very short breeding period. With a short lifespan after breeding, females demonstrated true semelparity. The mean cephalothorax width for ovigerous/post-ovigerous females was higher in 2008 than in 2009. These females attained the largest size in the population throughout the year. The number of eggs per female ranged from 28 to 147 (mean ± SE, 78 ± 1.8). There was a positive correlation between female size and fecundity. Recruitment occurred in late April and resulted in the highest population density in this month, whereas the lowest densities were observed during November to January. Despite a high percentage of ovigerous females carrying undeveloped eggs (72.3%), intramarsupial mortality was low (3.5%).  相似文献   

7.
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   

8.
Reproduction is a critical event in the life cycle of animals, and a high amount of energy is allocated to it. The aim of this study was to characterize the reproductive biology of two recently described species of Hyalella from the north-east region of state of Rio Grande do Sul in southern Brazil. The specimens were collected during 12 months from a stream source (Hyalella georginae) and from a water reservoir (H. gauchensis), in Palmeira das Missões municipality, state of Rio Grande do Sul. Upon sampling, ovigerous females and pairs in precopulatory behaviour were separated into microtubes. In the laboratory, the cephalothorax length (CL in mm) of all specimens was measured. Male size at onset of sexual maturity was larger than that of the females, in both species. There was a correlation between the size of paired males and females: larger males carried larger females, in both Hyalella species. Precopulatory pairs were found throughout the year; however, H. georginae had a higher frequency in spring, and H. gauchensis in autumn. There was a positive correlation between the CL of ovigerous females and the number of eggs/juveniles. A reduction in the number of eggs throughout the embryonic development was observed in H. georginae. The average fecundity of H. georginae was significantly higher than H. gauchensis. The differences between the reproductive biology of these species may be related to the physical and environmental conditions at which they are exposed in their habitats.  相似文献   

9.
《Journal of Natural History》2012,46(29-30):1801-1815
Records of Tanaidacea from the Isles of Scilly are collated; the published literature is reviewed, together with unpublished records from various sources. These data are supplemented by recent material collected in the archipelago between 2001 and 2010. A total of 10 species are now known from littoral and sublittoral habitats of the Isles. These records include the first published record for the British Isles of the tanaid Zeuxo holdichi, the known distribution of which is summarized. The apseudomorph Apseudopsis latreilli is common to abundant on littoral sandflats but Apseudes talpa generally replaces this species on more heterogeneous substrata and sublittorally. Tanais dulongii and Leptochelia savignyi are present throughout the archipelago among littoral algal-turf with embedded sediment. Zoogeographically, the list includes species from the temperate–boreal and, mainly, from Lusitanian waters.  相似文献   

10.
《Journal of Natural History》2012,46(6):1353-1365
Two new genera of Pilumnidae each with a single new species are described from southeastern Queensland waters. Priapipilumnus is defined by the greatly swollen base and simple blunt apex of the male first pleopod and the concomitant posteriorly protruding, bilobed, third abdominal segment. Takedana is separable by the very short spinous anterolateral margins, the swollen branchial regions, the moderately short walking legs, and the strongly spined chelae. Actumnus pugilator is reassigned to Bathypilumnus Ng and Tan, 1984.  相似文献   

11.
《Journal of Natural History》2012,46(29-30):1991-2010
Four new and four known species of soil nematodes belonging to the superfamily Tylencholaimoidea Filipjev, 1934 are reported from China. Tylencholaimus orientalis sp. nov. is characterized by having a 0.45–0.61‐mm body; a 5–6‐µm odontostyle; a monoprodelphic genital system with a short post‐uterine sac; and a conoid to hemispheroid tail. Tylencholaimus sinensis sp. nov. is characterized by having a 0.76–0.82‐mm body; a 7–7.5‐µm odontostyle; an amphidelphic genital system; a conoid to hemispheroid tail; and males with 32‐µm spicules and three ventromedians. Proleptonchus sinensis sp. nov. is characterized by having a 1.4–1.7‐mm body; wide amphids; 8–9‐µm odontostyle; a monoprodelphic genital system, the posterior branch with well‐developed uterus and oviduct rudiments; slender and slightly arcuate spicules; and a short conoid tail with thick cuticle at terminus. Dorylaimoides alpinus sp. nov. is characterized by having a 1.4–1.5‐mm body; a lip region offset by a depression; a 12–13‐µm odontostyle; an arcuate odontophore; an amphidelphic genital system with transverse vulva; and a tail that gradually tapers to a blunt terminus.  相似文献   

12.
《Journal of Natural History》2012,46(41-42):2599-2622
The taxonomy of the genus Metarhabditis is discussed with an emended diagnosis and a key to identification of its species. Three known species of Metarhabditis are described and illustrated. Metarhabditis amsactae (Ali et al. 2011) Sudhaus, 2011, a species recently transferred to the genus, is described in detail and its relationship with other congeners is discussed. The present population of Metarhabditis costai (Martins, 1985) Sudhaus, 2011 shows some minor differences with the original population in having slenderer individuals with relatively greater ‘a’ value, relatively smaller spicules and gubernaculum. Some minor differences are also noted in the present population of Metarhabditis andrassyana Tahseen et al. 2004 from the original population. The present population has distinct lateral fields, faint longitudinal striae, a nearly undifferentiated corpus and a relatively posteriorly located third genital papilla in males.  相似文献   

13.
The paper describes two new species of feather mites collected from the blue-throated blue flycatcher Cyornis rubeculoides (Vigors) (Passeriformes: Muscicapidae) in India (Meghalaya): Trouessartia kharkhanensis Constantinescu et al. sp. nov. (Trouessartiidae) and Proterothrix cyornissimilis Constantinescu et al. sp. nov. (Proctophyllodidae: Pterodectinae). Both sexes of T. kharkhanensis differ from the closest species, T. rubecula Jablonska, 1968 by having setae si and c2 lanceolate and setae c3 and sRIII with acute apex. In males of the new species, the adanal apodemes have a hook-like retroverse apophysis and the internal margins of terminal lamellae have a shallow invagination at the level of setae h3. Both sexes of P. cyornissimilis differ from the closest species, P. cyornis Mironov and Tolstenkov, 2013, mainly by the ornamentation of the dorsal shields: it is absent on the prodorsal shield and poorly expressed on the hysteronothal shield. In males of the new species, the supranal concavity is triangular and the genital arch has a pair of small ovoid sclerites at its tips.

http:/zoobank.org/urn:lsid:zoobank.org:pub:1671D6D4-8895-467B-A124-05EDBB0DF406  相似文献   


14.
The adult behaviour of Odontota dorsalis on its host plant Robinia pseudo-acacia was studied by following marked individuals in nature. Copulations often lasted several hours, and were characteristically followed by long escort phases in which males remain mounted atop females. Pairing lasted as long as several days. Most pairs broke up around the time of day when most females were ovipositing. Females normally laid a small cluster of eggs once per day. Both sexes mated repeatedly, and females did not resist copulations.

Long pairings in O. dorsalis may have evolved because the encounter rate between the sexes is high and costs to the female low. It is suggested that escort behaviour will be found in many other species with similar ecology and in which males remain mounted on females while copulating.  相似文献   

15.
《Journal of Natural History》2012,46(9-10):495-522
This paper describes five new species of earthworms belonging to the genera Amynthas and Metaphire (Megascolecidae: Oligochaeta) from Matsu, Taiwan. They are Amynthas bimontis sp. nov., Amynthas hsiyinensis sp. nov., Amynthas dongyinensis sp. nov., Amynthas dongjuensis sp. nov. and Metaphire matsuensis sp. nov. Amynthas bimontis is a small, quadrithecate earthworm with two pairs of spermathecal pores in 5/6/7 and two small genital papillae lateral to each male porophore. Amynthas hsiyinensis is quadrithecate with two pairs of spermathecal pores in 7/8/9, has numerous small genital papillae and is morphologically similar to Amynthas polyglandularis (Tsai, 1964) from northern Taiwan. Amynthas dongyinensis is sexthecate with three pairs of spermathecal pores in 6/7–8/9 and has simple male pore structure. Amynthas dongjuensis is octothecate with or without a genital papilla medial to each male pore. Metaphire matsuensis is sexthecate with three pairs of dorsolateral spermathecal pores in 5/6–7/8, and has each male pore surrounded by 0–10 small papillae on top of a cone-shaped everted copulatory chamber. DNA barcodes (the 5’-end sequences of the mitochondrial cytochrome c oxidase subunit I gene) of the five new species are also reported.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:2EBE3507-917B-4074-B73B-CF8DC88966B9  相似文献   

16.
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   

17.
In this paper we describe the postmarsupial development of the manca stages of Atlantoscia floridana (van Name, 1940). Ovigerous females were collected in Reserva Biológica do Lami, Porto Alegre, RS, Brazil and separately reared in small containers at 20°C (±1°C). After birth each newborn (manca I) was reared separately in order to observe the subsequent moults. In a period of about 12 h the animals underwent the first moult. The manca II stage lasts 9.16±1.57 days while manca III takes up a period of 9.96±1.05 days. Growth was observed through measurements of cephalothorax width. The three manca stages are described, illustrated and compared with the adults. The main distinguishing characteristics among mancas I, II and III are presented as well as the b/c and d/c co-ordinates of the noduli laterales.  相似文献   

18.
19.
《Journal of Natural History》2012,46(9):1303-1318
A new species of the demersal calanoid copepod Ridgewayia, R. boxshalli n.sp., is described from southern Japan. This is the first record of the genus in Japan. It is distinguishable from other congeners by the antennule and leg 5 of both sexes. In order to identify evolutionary trends, detailed observations were also carried out on the female genital structures using light and scanning electron microscopy for comparison with other calanoids. Their organization is characterized by two egg-laying ducts opening through paired gonopores into a small cavity, the genital atrium, covered by a genital operculum and opening to the outside through a distal atrial slit. No seminal receptacle is present. The unique morphological features and in situ feeding habit of Ridgewayia are also noted.  相似文献   

20.
《Journal of Natural History》2012,46(47-48):2961-2967
Explosive breeding is a common reproductive strategy, especially in anurans. In some cases of explosive breeding in anurans, intense aggressive interactions occur among males attempting to gain access to females, and for terrestrial species that mate in water, females may die by drowning during long mating struggles. Such occurrences are obviously detrimental to females, and may also cause a decrease in the reproductive success of males through depletion of energy without obtaining access to a live female. However, the males of the small Amazonian frog Rhinella proboscidea can promote the ejection of oocytes from the abdominal cavities of dead females and fertilize them. This behaviour can minimize losses to both partners during explosive reproduction events. The existence of such a “functional necrophile strategy” shows that there may be possible selection in favour of stronger and more persistent males in explosive breeders.  相似文献   

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