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1.
Egg deposition by the soil mites Trichouropoda (= Oodinychus) ovalis (C.L. Koch and Uroobovella (= Fuscuropoda) marginata (C.L. Koch), egg incubation and hatching behaviour were observed using continuous video-monitoring. The oviposition in both species was found to consist of three distinct phases. In Phase 1, both species engage in pre-ovipositional activity prior to the egg being extruded from the genital opening. Phase 1 lasted approximately 7.5 minutes in T. ovalis and about 6 minutes in U. marginata. Phase 2 involved egg deposition and lasted approximately 2.5 times longer in T. ovalis (88 seconds) than in U. marginata. Egg covering occurs in Phase 3, and in both species lasts about 25 minutes. Incubation time in U. marginata (137 hours) was approximately 30% shorter compared to that of T. ovalis, while the hatching time was 2 times longer (150 min) in the latter species.  相似文献   

2.
In the present study, we aimed to characterize the life history of the land snail Subulina octona integrating information on life-history traits and morphology. We also compared the histology of the free-oviduct and spermoviduct of ovoviviparous and egg-retaining species of subulinids. We considered as ovoviviparous the species in which the complete embryonic development as well as egg hatching occurs inside the parent’s body and, at the end of this process, the parent releases juveniles instead of eggs. We considered as egg-retaining the species in which a great part of the embryonic development takes place inside the parent’s body and the eggs laid contain well-developed embryos. The results showed that the free-oviduct of both ovoviviparous and egg-retaining species shows a histological arrangement that confers greater strength to its walls and is probably related to egg retention. The wall of the spermoviduct is formed by pseudostratified columnar epithelium, with cell apical processes (probably cilia), and by underlying secretory cells. In gravid egg-retaining snails, the eggshells appear in close contact with the secretory cells of the spermoviduct. This fact suggests that these cells play a role in eggshell formation. The present study is the first account for histological features of S. octona, Allopeas gracile and Allopeas micra. The life history of S. octona is a combination of long lifespan, early sexual maturity, indeterminate growth and egg retention. Egg retention limits the number of young that can be produced in one reproductive event. However, the reproductive strategy adopted by S. octona, associating egg retention and K-strategism, compensates this cost of retaining eggs, because the reproductive success may be enhanced as a result of the higher survival of juveniles and the possibility of performing several reproductive events during the year.  相似文献   

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The embryonic development of the squid Loligo vulgaris was observed from 183 egg masses collected from special devices deployed throughout Cabrera National Park (Baleares Islands, western Mediterranean Sea). Sequence alignment analysis of the cytochrome oxidase I gene revealed that all embryos belonged to L. vulgaris. In total, 549 egg capsules were examined. Viable egg capsules (n = 420) were classified into one of five maturation stages according to the primary external features. The length of the viable egg capsules varied between 40 and 170 mm, and increased with embryonic development. The non-viable capsules (n = 129) were categorized into four groups: I (Ginger root), non-viable II and III, and empty egg capsule (IV). The percentage of non-viable capsules (i.e. grades I, II and III) was 92.25%. Empty capsules accounted for 7.75% of the total non-viable egg capsules. Embryonic development was classified into a second scale of eight stages. Egg capsule stage and embryonic stage were significantly related (n = 420; p < 0.001), facilitating the determination of the embryo developmental phase based on the outward appearance of the egg capsules. The embryo development stage based on the external features of the egg capsules might constitute an innovative tool for in situ embryological data collection. This new method is neither time consuming nor invasive, and could be helpful in fishing cruises, for scuba diving visual census in natural habitats and for laboratory culture. Slight variability in the developmental embryonic stages within egg capsules from the same egg mass was identified. The origin of this asynchrony is discussed. Chronological appearance of organs was similar to that of the six loliginid species previously examined. However, some developmental changes in the timing or rate of events (heterochronies) were observed: Hoyle’s organ was formed earlier in L. vulgaris and the appearance of ventral chromatophores was slightly delayed (2 days) compared with the other species considered.  相似文献   

5.
《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   

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《Journal of Natural History》2012,46(23-24):1441-1465
In Argentina, five genera and 34 species are recorded, in the subfamilies Rhopalinae and Serinethinae. Harmostes apicatus Stål; H. brevispinus Blöte; H. corazonus Distant; H. corizoides Jensen-Haarup; H. dorsalis Burmeister; H. gravidator (Fabricius); H. imitabilis Harris; H. insitivus Harris; H. marmoratus (Blanchard); H. minor (Spinola); H. parafraterculus Göllner-Scheiding; H. petulans Harris; H. procerus Berg; H. prolixus Stål; H. reflexus viscens (Dallas); H. serratus (Fabricius); H. signoreti Reed; Jadera aeola aeola (Dallas); J. choprai Göllner-Scheiding; J. decipiens Göllner-Scheiding; J. golbachi Göllner-Scheiding; J. haematoloma (Herrich-Schaefer); J. obscura (Westwood); J. parapectoralis Göllner-Scheiding; J. sanguinolenta (Fabricius); Niesthrea agnes Chopra; N. josei Göllner-Scheiding; N. pictipes (Stål); N. similis Chopra; N. vincentii (Westwood); Liorhyssus hyalinus (Fabricius); L. lineatoventris (Spinola); Xenogenus gracilis Berg; X. picturatum Berg; and X. extensum Distant. New locality records are given for Buenos Aires; Catamarca; Corrientes; Córdoba; Chaco; Entre Ríos; Jujuy; La Pampa; Mendoza; Misiones; Neuquén; Río Negro; Salta; San Juan; San Luis; Santiago del Estero; Tierra del Fuego.  相似文献   

8.
《Journal of Natural History》2012,46(29-30):1891-1910
One hundred and ninety-one frogs collected in Papua New Guinea from 10 species of the genus Litoria, namely, L. angiana, L. arfakiana, L. caerulea, L. congenita, L. eurynastes, L. gasconi, L. infrafrenata, L. iris, L. kumae and L. modica, were examined for helminths. Eighteen species of helminths were found: one species of Monogenea, Parapolystoma bulliense; three species of Digenea, Diplodiscus amphichrus, Halipegus zweifeli and Mesocoelium monas; 13 species of Nematoda, gravid specimens of Aplectana macintoshii, Cosmocerca novaeguineae, Falcaustra papuensis, Maxvachonia adamsoni, Maxvachonia flindersi, Maxvachonia ingens, Meteterakis crombiei, Moaciria moraveci, Parathelandros mastigurus, Physalopteroides milnensis, Pseudorictularia dipsarilis, Seuratascaris numidica, and larvae (in cysts) of Abbreviata sp. and, one species of Acanthocephala, Pseudoacanthocephalus bufonis. Mean number of helminth species per host species was 3.0 ± 1.4 SD (range 1–5), mean number of helminth species per infected frog was 1.1 ± 0.4 SD (range 1–2), and mean number of helminths per infected host was 33.3 ± 5.8 SD (range 1–36). Twenty-eight new host records and two new locality records are reported. The biogeography of the recovered helminths is discussed.  相似文献   

9.
Cassidinae Gyllenhaal? is the second largest subfamily of Chrysomelidae (Coleoptera), which presents characteristic morphology, biology and behaviour. The current study describes the life cycle of Paraselenis(Spaetiechoma) dichroa (Germar), ?determining biological and behavioural aspects as well as the action of natural enemies on populations, when the species has maternal care. The study was conducted between February and April 2015 in the National Forest of Passa Quatro, municipality of Passa Quatro, Minas Gerais state, Brazil. Daily observations were made (morning and afternoon) to evaluate the offspring of females on Ipomoea sp. and Merremia macrocalyx (O’Donell?) (Convolvulaceae), as well as the actions of natural enemies on the young. The eggs are deposited on the midrib and abaxial surface of leaves (n = 25). Egg clusters are pedunculated, arranged in groups and devoid of any cover. On average, each female produced 27.3 ± 5.6 (n = 16) eggs, with a mean incubation period of 12.7 ± 2.9 days (n = 10 females with their young). The larvae remained grouped in the leaves throughout development, except when they fed. They retained faeces and exuviae as a stacked faecal structure on their mobile urogomphi (caudal process) like a faecal shield. The mean number of larvae per female was 12.7 ± 10.1 (n = 19) and the larval period lasted 24.9 ± 4.5 days (n = 12). Pupation occurred on the stem of the plant (n = 16). On average there were 8.1 ± 8.5 individuals for pupae progeny (n = 14). The mean duration of the pupal stage was 10.4 ± 3.3 days (n = 5). Overall, 3% of adults emerged (n = 13 individuals), with a total cycle time of 41.3 ± 8.4 days (n = 6). Adults are sexually dimorphic in the elytral shape. Females remain with the offspring throughout development. The natural enemies of immatures were Emersonella pubipennis Hansson? (Hymenoptera: Eulophidae), Tachinidae (Diptera) and Stiretrus decastigmus (Herrich-Schaeffer?) (Heteroptera: Pentatomidae), Conura sp. Spinola? (Hymenoptera: Chalcididae) and Brachymeria sp. Westwood? (Hymenoptera: Chalcididae). The information presented here on the natural history of P. dichroa are important as they may serve as a starting point to understand evolutionary questions and multispecies interactions.  相似文献   

10.
《Journal of Natural History》2012,46(17-18):1119-1129
Despite their abundance and diversity, Neotropical spiders have been the subject of relatively few studies of behavioural ecology. The sexual behaviour and maternal care of the spider Aglaoctenus lagotis (Lycosidae) is described here. We performed experimental manipulations to test the hypothesis that males are attracted by female cues in the web. Two predictions were tested: (a) webs used by a virgin female will attract more males than webs used by an inseminated female; (b) the main cue in the web is chemical, so webs recently used by virgin females will attract more males than those that are not recently used. Additionally, we tested the hypothesis that maternal care increases offspring survivorship. Results showed that males are attracted by recently used webs (z = 0.0015; p = 0.037; z-test) and webs of virgin females (z = 0.041; p = 0.036, z-test). Male sexual behaviour presented three different categories: court, pre-mate and mate. After the mating, the females built a cocoon that was transported adhered to the spinnerets and held by the last pair of legs. After the hatching of the eggs, the young migrated to the dorsal region of the mother's body for 5 days. During maternal care the mother eliminates a yellowish drop from its oral cavity, which is collected by the young. During the development of the young until adulthood, the offspring that have their mother present in the first stages of life have greater survival compared with those without maternal care. Our results make it possible to perform comparative analyses between a South American Lycosidae species and other species distributed worldwide.  相似文献   

11.
《Journal of Natural History》2012,46(37-38):2339-2345
The morphological effects of nematode parasitism by Pheromermis myrmecophila were investigated in two species of ants, Lasius flavus and Lasius niger, collected on Clare Island, Ireland. Infected males and queens were found for L. flavus but only infected queens in L. niger. The numbers of nematodes present in each infected specimen were counted and their lengths were measured. Head width, femur length and wing measurements were made for infected and non-infected individuals of both species. In queens, the length of the nematodes decreased as the number per ant increased. When single nematodes were present their mean lengths were significantly greater in L. flavus than in L. niger. In addition to the reduction in wing size for all parasitized specimens, head widths and femur lengths of the queens were significantly different in both species. A log–log graph of radial cell length versus width suggested a linear reduction of wing size.  相似文献   

12.
《Journal of Natural History》2012,46(25):2339-2354
The parasitoid complex of spiders was studied in three different sites of a forest and, for comparison, in open habitats in north‐western Lower Saxony (Germany). Qualitative data and, for four spider species, detailed quantitative rearing data were obtained. At least 25 parasitoids of spiders were recorded (23 species of Hymenoptera and two species of Diptera). External parasitoids of spiders were rare in the woodlands; only up to 1% of the spiders collected by hand searching and sweep netting had ectoparasitoids. During the investigation 23 parasitoid species were reared from spider egg masses, 10 of them occurring in woodlands. Two species were secondary parasitoids. Several parasitoid–host relationships were recorded for the first time. Egg masses of Floronia bucculenta were parasitized up to 5% by two species of the genus Gelis. Up to 10% of the egg masses of Linyphia hortensis were parasitized by Aclastus species. Egg masses of the spider genus Ero were parasitized by three species, causing an overall mortality of 40%. For egg masses of Agroeca spp. parasitization at some locations was up to 60%. An overview of the Central European parasitoid complex of spiders is provided.  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.
Population and reproductive behaviour aspects of the glass frog Espadarana prosoblepon are well known for populations from Central America, but similar information is lacking for populations from South America. We recorded the reproductive ecology of a population of the glass frog E. prosoblepon in the city of Armenia, Central Andes of Colombia. With weekly surveys with mark-recapture between December 2013 and November 2015, we monitored activity patterns and evaluated if the probability of males mating is associated to their body size or to chorus tenure (i.e. the number of nights a same individual is calling for attracting a mate). In addition, upon observing an amplexus, we recorded the behaviour of the individuals until oviposition and noted characteristics of egg clutch. We recorded 47 males and 32 females, nine amplexus events, eight ovipositions, and 21 egg clutches (35.4 ± 4.79 eggs per clutch, = 29). Activity of males and females and the number of egg clutches were positively correlated to rainfall. Mating success of males was not associated to their body size, but it was positively associated to longer chorus tenure; clutches from large females had a higher number of eggs than clutches from small females. Oviposition occurred on average 3.76 ± 1.74 hours after we first observed the amplexus, occurring 93.1% of the time in fronds of Selaginella geniculata at an average height of 1.58 ± 0.44 m. After the oviposition, the male left the site, while the female remained between 30 and 45 min, partially covering the eggs. The reproductive behaviour of E. prosoblepon did not vary widely between a population in Costa Rica and our population in time to oviposition, and mating success of males associated to chorus tenure; however, in our study population we recorded a larger clutch size and the preference for S. geniculata fronds as oviposition substrate.  相似文献   

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Phylogenetic relationships of the Aegean Helix cincta and Helix nucula with congeneric species found in Greece were inferred using mitochondrial DNA sequence data. Twenty-three specimens from mainland Greece, Aegean Islands, Cyprus and North Africa were analysed, revealing that (1) H. nucula is monophyletic, (2) H. cincta from Greece and Cyprus is paraphyletic, and so questions arise regarding the taxonomy of this species, and (3) H. cf. cincta from Tunisia might be considered as a distinct evolutionary lineage. Moreover Helix valentini, an endemic species of Kalymnos Island group, is clustered within the lineage of H. c. anatolica, so supporting the synonymy of the two ‘species’, and the elevation of H. c. anatolica to species level. Hence, our results stress the need for a taxonomic reconsideration of H. cincta in the Aegean Sea, indicating that sequence data can prove useful in overcoming taxonomic issues at both species and subspecies level.  相似文献   

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《Journal of Natural History》2012,46(9-10):565-598
Thirteen new species of the genus Helina are described: H. briaroacantha sp. nov., H. corrugicerca sp. nov., H. cuneicauda sp. nov., H. curvoifemoralisa sp. nov., H. deqinensis sp. nov., H. dianibrunneigena sp. nov., H. kytososurstylia sp. nov., H. mesolobata sp. nov., H. nigrointermedia sp. nov., H. nudusimacula sp. nov., H. spinusiabdomena sp. nov., H. tigrisipedisa sp. nov., and H. yanzigouensis sp. nov.  相似文献   

19.
Endemic to the Tibetan Plateau, Nanorana parkeri figures among the highest altitude amphibians in the world. The present work, which was conducted in an alpine marsh at 4300 m altitude, is the first report of the species’ reproductive ecology. The breeding season, as indicated by the presence of amplectant pairs and fresh eggs in ponds, lasted from early Mary to early July. The ratios of adult male to female were 1.3 in hibernation ponds and 2.3 in spawning ones. Males were smaller than females. Amplexus was typically axillary (81.7%), with a few exceptional amplexus in which a male clasped another male or object rather than gravid females. Scramble competition occurred in 6.8% of the normal amplexus located. The body sizes of amplexed couples correlated positively. Deposited eggs were attached to submerged plants solitarily (60.5%) or in small clusters (39.5%), and the scattered arrangement of individual eggs could be a strategy to ensure embryonic development in oxygen-poor environments. Clutch size averaged 189 [standard deviation (SD) = 64], and correlated positively with female body size; egg size averaged 2.18 mm (SD = 0.10), independent of female body size; both traits within a clutch were negatively related with each other even controlling for female body size. Relatively few and large eggs laid by the Tibetan frogs, compared with those by lowland aquatic-spawning anuran species, should be adaptive to the harsh high-altitude conditions. Larvae hatched from eggs after 16.4 days on average (SD = 5.8). Froglets emerged between late July and early August, but some tadpoles were present in winter. These findings may help to understand the evolution of amphibians in extreme environments and to protect these remote species.  相似文献   

20.
《Journal of Natural History》2012,46(39-40):2419-2441
Two brachyurans of the varunid genus Hemigrapsus from the northwestern Pacific Ocean have invaded coastal regions of the north Atlantic – Hemigrapsus takanoi (sibling species of Hemigrapsus penicillatus) and Hemigrapsus sanguineus in Europe and the latter in the USA. Parasites are known from these crabs in their native habitats, but except for an undescribed larval nematode, none has been found in those examined from their new locations. These parasites include metacercariae of eight species of microphallid trematode, the rhizocephalan barnacles Polyascus polygenea, Sacculina nigra and Sacculina senta, and the obligate gut-inhabiting mesomycetozoan Enteromyces callianassae (potential parasite). The following have been identified in four of the other eight Pacific crabs within the genus (Hemigrapsus nudus and Hemigrapsus oregonensis, northern hemisphere; Hemigrapsus crenulatus and Hemigrapsus sexdentatus, southern hemisphere), none of which have been geographically displaced: metacercariae of two microphallid trematodes; cystacanths of three acanthocephalans Profilicollis antarcticus, Profilicollis botulus and Profilicollis novaezelandensis; larval nematode Ascarophis sp.; nematomorph Nectonema zealandica; entoniscid isopod Portunion conformis; mesomycetozoan Taeniella carcini; and nemertean egg predator Carcinonemertes epialti. The likelihood of the displaced species of shore crabs being rejoined with their native parasites or their susceptibility to becoming infected by similar parasites in their new locations is discussed. In future global displacements of parasitized Hemigrapsus species it is possible that their most serious parasites, rhizocephalans and entoniscid isopods, may infect previously uninfected species. For example, the two eastern Pacific species of Hemigrapsus (H. nudus and H. oregonensis) may be vulnerable to the rhizocephalans and may in turn be a source of entoniscids transported elsewhere.  相似文献   

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