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1.
The ability of members of the arachnid order Solifugae to climb smooth, vertical surfaces and the organs involved in this behavior are investigated. Macroscopic, microscopic, and scanning electron microscopic observations are made of a palpal organ called the suctorial organ. Observations of the behavior but not the microstructure have been made in the past. Histological examination illustrates the internal gross anatomy of this structure and scanning electron microscopy demonstrates the fine structure in adults of four genera: Eremobates (Eremobatidae), Eremochelis (Eremobatidae), Eremorhax (Eremobatidae), Ammotrechula (Ammotrechidae), as well as an unidentified late stage immature and third stage instar. The suctorial organ is most likely primarily used for prey capture in the wild.  相似文献   

2.
First generation egg clusters of Elasmucha grisea are more closely guarded than second generation clusters. The ovaries of this species are structured to enhance this behavior. The population of E. grisea from S-W Poland breeds in the spring (May–June) and late summer (July–August). The second generation clutches contain fewer eggs and are destroyed 3–4 days after oviposition by predators and parasitoids.The ovary structure in the studied species differs from that found in other Heteroptera. The average number of ovarioles per ovary is 24 while in the other investigated species the number of ovarioles per ovary is 6–7. Lateral oviducts are elongated and the ovarioles are arranged in a pennate pattern. Each ovariole contains only one growing ovarian follicle. Differentiation of the ovarioles and ovarian follicles is synchronised thus enabling simultaneous oviposition. A comparative analysis of the ovary structure during the life cycle, particularly the presence of atresive ovarian follicles in the ovarioles of egg- and nymph guarding females, as well as the shape and structure of the apical part of the tropharium all support the hypothesis of cooperation between females in E. grisea. A similar ovary structure has been observed in the Coccoidea (Hemiptera, Homoptera) which indicates presocial behavior.  相似文献   

3.
The relation between the duration of ontogenesis of Polistes dominula males and the social structure of their colonies was studied in July–August 2012. Males developing in successful colonies with a foundress passed through the later-instar larval and pupal stages more quickly than those in orphaned colonies. Successful colonies more often produced males with weakly melanized mesopleura as compared with orphaned ones. Males from the two categories of colonies did not differ in the head and wing size. The influence of mechanical stress and nutrition during larval development and the specific signaling behavior of the foundresses on the male phenotypic diversity in P. dominula is discussed.  相似文献   

4.
Thermo-sensitive semi-IPN hydrogels were prepared via in situ copolymerization of N-isopropylacrylamide (NIPAAm) with poly(ethylene glycol)-co-poly(ε-caprolactone) (PEG-co-PCL) macromer in the presence of sodium alginate by UV irradiation technology. The effects of the sodium alginate content, temperature, and salt on the swelling behavior of the as-obtained hydrogels were studied. The results showed that the swelling ratio of the hydrogels increased with the increasing sodium alginate content at the same temperature, and decreased with the increase in temperature. The salt sensitivity of the semi-IPN hydrogels was dependent on the content of sodium alginate introduced in the hydrogels. The mechanical rheology of the hydrogels and in vitro release behavior of bovine serum albumin (BSA) in situ encapsulated within the hydrogels were also investigated. It was found that the introduction of sodium alginate with semi-IPN structure improved mechanical strength of the hydrogels and the cumulative release percentage of BSA from the hydrogels. Such double-sensitive semi-IPN hydrogel materials could be exploited as potential candidates for drug delivery carriers.  相似文献   

5.
Prochilodus magdalenae is an endemic freshwater fish that occurs in the Magdalena, Sinú and Atrato hydrographic basins. It has an important economic role and is a food resource for the artisanal fishing communities. Its socioeconomic importance contrasts with the current status of its fisheries, where stocks are being depleted. Considering its importance and lack of information on its genetic structure, we used seven microsatellite markers to assess the genetic structure of wild populations of P. magdalenae. The genetic diversity was assessed and the population genetic structure was estimated through Fst, analysis of molecular variance and Bayesian analysis. A total of 290 alleles were found in all loci throughout all population. The high polymorphism contrasts with the levels of observed heterozygosity (Ho = 0.276), which are the lowest values recorded for the family. We found three populations of bocachico coexisting throughout the studied system, contradicting the hypothesis that freshwater migratory fish form panmictic populations. These results on the genetic structure of P. magdalenae constitute tools for a better understanding of the behavior and biology of this species, contributing to fish management and conservation programs.  相似文献   

6.
The structure of the male genitalia of Aedes diantaeus was studied under scanning electron and optical microscopes. The tridimentional structure of the coxite is described and the structure of apical and basal warts and the arrangement of setae on the coxite are clarified. The structure of the claspette, i.e., the position of the claspette’s wing (filament) in relation to the claspette’s stem and also the shape and the structure of the wing were studied. The shape of the proctiger and the position of the paraprocts were investigated. A large membranous area forming paired lobes on the dorsal surface of the proctiger is described. Significant differences between Aedes diantaeus and A. caspius, A. cantans, and A. communis in the structure of the coxite, claspette, and proctiger, are demonstrated.  相似文献   

7.
In this study we examined the territorial, courtship and coupling behavior, mating interruptions and influence of sunlight on mating behavior in Spalgis epius (Westwood). We constructed an ethogram of territorial and courtship behavior, and catalogued the sequence of behavioral acts associated with mating behavior. Mating behavioral acts were divided into four repertoires i.e. pre-courtship, pre-coupling, coupling and post-coupling behaviors. Totally 22 behavioral acts were recorded from four repertoires. Tree canopy, canopy height and sunlight conditions are the important factors that influence copulation in S. epius. The courtship activity led to successful copulation in 71.9 % pairs. Incidence of different types of courtship and copula interruptions in S. epius was also recorded.  相似文献   

8.
Despite the taxonomic value of pollen morphology within the tribe Vernonieae, a detailed study of the pollen of the subtribe Elephantopinae is still lacking. The pollen morphology of ten species, representing three of the four genera of the subtribe, Elephantopus, Pseudoelephantopus and Orthopappus, was studied with LM, SEM, and TEM. The pollen of all the species studied was found to be echinolophate, although the differences in aperture features and both sculpture and exine structure allowed recognizing two pollen types. The species of Elephantopus (except for E. elongatus) and Pseudoelephantopus share the regular or more or less regular ridges pattern, the colporate condition but with the ectoapertures little developed, and the acaveate exine structure. From the sculpture and the apertures, the pollen of Caatinganthus harleyi was found to be similar to that of Elephantopus and Pseudoelephantopus. The pollen morphology of the monotypic Orthopappus, which is shared with that of E. elongatus, was further investigated for the first time. We found that it differs from that of the other species in having an irregular pattern of ridges, colporate condition but with a well-developed ectoapertures, and caveate exine. Additional studies of the exine structure and apertures features, coupled with molecular phylogeny, are needed to understand the evolution of pollen characters and re-evaluate the intergeneric relationships within the tribe.  相似文献   

9.
We investigated the temperature- and pressure-dependent structure and phase behavior of a solvated oligopeptide, GVG(VPGVG), which serves as a minimalistic elastin-like model system, over a large region of the thermodynamic phase field, ranging from 2 to 120°C and from ambient pressure up to ~10 kbar, applying various spectroscopic (CD, FT-IR) and thermodynamic (DSC, PPC) measurements. We find that this octapeptide behaves as a two-state system which undergoes the well-known inverse-temperature folding transition occurring at T ≈ 36°C, and, in addition, a slow trend reversal at higher temperatures, finally leading to a reentrant unfolding close to the boiling point of water. Furthermore, the pressure-dependence of the folding/unfolding transition was studied to yield a more complete picture of the p, T-stability diagram of the system. A molecular-level picture of these processes, in particular on the role of water for the folding and unfolding events of the peptide, presented with the help of molecular-dynamics simulations, is presented in a companion article in this issue.  相似文献   

10.
The structure of the ovipositor sclerites and musculature was studied in the tephritid fly Carpomya schineri (Loew) whose larvae develop in the fruits of Rosa. The structural characters of the ovipositor of this species facilitating laying eggs into such fruits are discussed. The ovipositor musculature and functioning in Carpomya are very similar to those in Ceratitis and Bactrocera; species of all these genera lay eggs in fruits. In the details of the ovipositor musculature, Carpomya is more similar to Ceratitis than to Bactrocera. The genera Carpomya, Ceratitis and Bactrocera are phylogenetically close but Ceratitis and Bactrocera belong to sister tribes within one subfamily, Dacinae. Thus, morpho-functional similarity of the ovipositor structure may not only reflect close relationship but also result from common adaptive transformations.  相似文献   

11.
12.
Parental behavior in ten pairs of male and female red-backed voles, Clethrionomus rutilus, was studied under laboratory conditions. Significant sex differences were found in total time spent in the nest, time spent by adults alone in the nest, grooming time, and nest-building activity; in half of the males under study, the level of paternal care was extremely low. These findings indicate different paternal contributions of female and male red-backed voles into the rearing of young, in agreement with the spatial-ethological structure of populations of this species. Parental behavior of C. rutilus is discussed in comparison with that of other species of the subfamily Microtinae.  相似文献   

13.
Members of the basal hexapod group Collembola perform indirect sperm transfer; males deposit spermatophores on the soil and these are then picked up by females for insemination. Orchesella villosa exhibits a dissociated mating behavior, while Allacma fusca has either associated mating behavior or, more commonly, produces spermatophores without pairing. Sperm ultrastructure in the two species has been studied by TEM and SEM observations to estimate the volume of these cells. The sperm number into each spermatophore has been determined by counting the fluorescent nuclei after Hoechst staining of sperm droplets squash preparations. Sperm droplets at the apex of spermatophores contain numerous spermatozoa of typical appearance, wound up and with a long anterior appendage (peduncle). Sperm droplets of Orchesella villosa are smaller (about 10 times) than in A. fusca, however they contain substantially more sperm cells (about three times). These differences could be explained as follows: (a) sperm of O. villosa are shorter than those of A. fusca (58 and 107 μm, respectively) and thus the volume of a single sperm of O. villosa is about 10 times smaller than in A. fusca; (b) considering the volume of sperm droplets and of sperm cells, the estimated number of sperm cells would be higher in A. fusca than in O. villosa; and (c) the conspicuous reduction of the sperm cells observed in A. fusca is likely linked to the aberrant meiosis present in this species, as well as in all Symphypleona studied so far, that causes a loss of 50% of their sperm.  相似文献   

14.
Age specific mating incidence, mating behavior, mate recognition cues and effect of sexual status on mating of ladybird beetle, Anegleis cardoni (Weise) (Coleoptera: Coccinellidae) were studied in detail. The mating duration was very short (14.40 ± 0.72 min) in comparison to other ladybirds. Courtship was male dominated and was displayed in steps, viz. approach, watch, examine, sharp turns, mount, attempt and mate. Sharp turns is an additional behavior observed during courtship in this ladybird, and is characterized by sharp turning movements towards the mate, and is undertaken by both males and females. Active mating of A. cardoni involved multiple strokes of the aedeagus. Mating duration and the number of strokes were higher in unmated males than in mated ones. Results reveal that physical cues probably play a role in the initiation of courtship, while chemical signals are probably involved in the continuation of courtship, culminating in intromission. The removal of male antennae and obscurity of elytral patterns significantly decreased mating success, whereas female antennal ablation and obscuring of the pronotum did not affect mate recognition.  相似文献   

15.
Temporal variation of the helminth infracommunity structure in the Gafftopsail pompano Trachinotus rhodopus was studied during bi-monthly revisions of samples collected offshore from Puerto Ángel, Oaxaca (Mexican Pacific) in 2018. In total, 110 specimens of T. rhodopus were subjected to a parasitic review. Helminths found were identified to the lowest possible taxonomic level (six species and three genera) by means of morphological and molecular data. Attributes of the helminth infracommunities are described through statistical analyses, showing stability in terms of their richness throughout the year. However, variations were found in helminth abundance related to the seasonality of samplings, which may be associated with the life cycles of the parasites, the host species' gregarious behavior, the availability of intermediate hosts, and/or the diet of T. rhodopus.  相似文献   

16.
The cephalic portion of the foregut of Neopachygaster is clearly subdivided into the pharynx and oesophagus. The precerebral pharynx is transformed into a well-developed anterior pharyngeal pump with two unpaired dilators and an intrinsic layer of the muscle fibers. There are two pairs of the posterior pharyngeal dilators, attached to the pharynx just behind the brain. According to these features, the pharynx of Neopachygaster has the most plesiomorphic structure among all the members of Stratiomyidae studied so far.  相似文献   

17.
《Palaeoworld》2019,28(3):381-402
The infrageneric taxonomy of the genus Cephalotaxus Siebold et Zuccarini ex Endlicher (Taxaceae) is controversial as morphological characters have been doubted to change coherently among species. Although the epidermal features are considered as important characters in the taxonomy of conifers, they have not been systematically studied in this genus. Neogene foliage shoots with well-preserved epidermal structure not only can provide systematic links to the extant species, but also have implications for the taxonomical definition of the extant species by their epidermal features. In this paper, the morphologies of leafy shoots combining epidermal structure of a Neogene Cephalotaxus, which was collected from the middle Miocene of Southwest China, and ten extant species (variants) were studied. Morphology as well as epidermal structures was compared among species (variants) in Cephalotaxus. Based on the comparisons, the taxonomical definition of extant species in genus Cephalotaxus are discussed. Our results indicate that leaf morphological characters in combination with the features of epidermal structure can distinguish species in genus Cephalotaxus. The fossil foliage shoots from the middle Miocene of Southwest China were assigned to a new species, C. maguanensis n. sp., which shows close affinities to the extant C. hainanensis. On the basis of leaf and epidermal information, we suggest there are seven extant species in Cephalotaxus. With global cooling and the uplift of the Qinghai-Tibet Plateau since the middle Miocene, the cooling climate induced the differentiation and southward expansions of C. maguanensis, and its extant offspring, C. hainanensis, is distributed to Hainan Island and the Indo-Chinese peninsula.  相似文献   

18.
Males of Parasitina and Dermanyssina (Gamasida = Mesostigmata) have chelicerae modified to function as gonopods. The slit-like spermatotreme in the movable digit of the chela in males of Parasitina was studied in three species: in Pergamasus quisquiliarum and Holoparasitus sp. a rather simple slit is indeed present, whereas in Vulgarogamasus kraepelini the structure is represented by a fine duct traversing the movable digit. The spermatodactyl studied in two phytoseioid species (Phytoseiulus persimilis, Blattisocius dentriticus) of Dermanyssina is a slender process arising from the movable digit and containing a fine duct which is formed by cuticular folds. The spermatodactyl of these species thus differs remarkably from that described in Veigaia sp. The diversity of these structures seen in the few taxa studied up to now is discussed under functional and systematic aspects.  相似文献   

19.
The herbaceous vine Aristolochia contorta (Aristolochiaceae) is a rare plant with a fragmented area in East Asia. Confocal laser-scanning microscopy and stereomicroscopy were employed to examine the seed and embryo structure. This is the first research on embryo anatomy in Aristolochia. Shape and structure of this embryo may be phylogenetically significant. The seed structure of A. contorta is similar to that of other Aristolochia species. Considerable variation is found for productivity traits; the average seed set is rather low (26.7%). The studied seed and embryo traits of A. contorta are found to be variable, but may be potentially informative at the genus and species level. The restricted productivity and reduced population size threaten the continued survival of A. contorta and, perhaps, the butterfly that depends on it.  相似文献   

20.
Oviposition and the development of larvae in Hydrachna cruenta Müller 1769 was studied using methods of light and scanning electron microscopy. Some features of similarity in the reproductive behavior and development of larvae were noted between H. cruenta and terrestrial trombiculid mites: spermatophore fertilization, the presence of one eggshell, tolerance to short-term egg drying, and formation of the stylostome. The life of H. cruenta larvae in water during the search for a host may be regarded as an adaptation of this species to a new habitat.  相似文献   

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