Polygonia C-aureum Research Articles

Material-structure collaborative design for broadband microwave absorption metamaterial with low density and thin thickness

There is a great demand for the metamaterials with low density, thin thickness and broadband microwave absorption in the aeronautic stealth domain. However, it is still a great challenge to achieve satisfactory impedance matching between free space and metamaterials subjected to above constraints. To address this issue, a material-structure collaborative approach was proposed for designing excellent microwave absorption metamaterial with low density and thin thickness, which includes nanomaterial synthesis, unit cell optimal design and absorption mechanism analysis. The 3D Graphene-Carbon nanotubes-Nickel nanomaterial was firstly synthesized by in-situ growth method for fabricating the low-density metamaterial. Inspired by the natural anti-reflection microstructure of Polygonia c-aureum's eye, the unit cell of metamaterial was designed. Size parameters optimization of designed unit cell was conducted with the efficient immune genetic algorithm. The optimized metamaterial is extremely advantageous in effective absorption bandwidth (EAB, reflection loss ≤ −10 dB), low density and thin thickness, which can achieve 29.1 GHz EAB and equivalent density as low as 0.65 g/cm3 (the areal-density is 3.58 kg/m2) with thickness of only 5.5 mm. The proposed material-structure collaborative approach provides an efficient and systematic avenue for designing broadband microwave absorption metamaterials.

Temporal shift between daily sperm movement and mating (sperm reflux) in the Asian comma butterfly, Polygonia c‐aureum

AbstractTemporal changes in mating behavior and daily sperm movement were examined in adult males of the butterfly Polygonia c‐aureum L. (Lepidoptera: Nymphalidae), reared under L15:D9 photoperiod at 21 °C. In this butterfly, when extra sperm is present in the duplex (storage organ) at mating, sperm reflux occurs: extra sperm are moved from the duplex to the lower and middle portions of the vasa deferentia by peristaltic movement of the lower portion of the vasa deferentia. It is known in several moth species that daily sperm movement from the testis to the upper portion of the vasa deferentia and from the upper vasa deferentia to the duplex occurs in a circadian manner. If sperm reflux and daily sperm movement occur at the same time, it could create confusion, because these sperm movements are directed oppositely. In this study, we examined the temporal changes of sperm movement and mating behavior in P. c‐aureum in order to clarify whether the two sperm movements are separated in time. Our results showed that most matings occurred during the second half of the photophase, whereas daily eupyrene (nucleate) sperm movement from the upper to the middle portion of the vasa deferentia occurred immediately after light on (early photophase), indicating the presence of a time lag between mating and daily sperm movement. As sperm reflux occurs during mating, these two oppositely directed sperm movements could be performed without conflict.

The complete mitochondrial genome of Polygonia c-aureum (Lepidoptera: Nymphalidae) from Yizhou of China and its phylogeny

The complete mitochondrial genome (mitogenome) of Polygonia c-aureum, from Yizhou of China, is a circular molecule of 15,202 bp in length, containing 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs, and a control region. The A + T content of the overall base composition is 80.6%. All of the 13 PCGs are begun with ATN (one with ATC, four with ATT and seven with ATG) as start codon except cox1 using CGA. Ten genes are terminated with TAA as stop codon, cox2, nad4 and nad5 end with an incomplete stop codon (T). The newly sequenced mitogenome will increase the basic information of Nymphalinae phylogenetic research and can help to better understand the phylogenetic status of P. c-aureum.

Effects of photoperiod and aging on the adult spermatogenesis of Polygonia c-aureum (Lepidoptera: Nymphalidae), in relation to adult diapause.

Adult spermatogenesis of Polygonia c-aureum was compared between non-diapausing and diapausing butterflies before overwintering. This butterfly has seasonal polyphenism, i.e., summer and autumnal forms. Summer form butterflies that emerged in summer reproduce shortly after emergence, while autumnal forms that emerged in autumn mate in spring. Immatures were reared under either a long photoperiod, which produced the summer form without diapause or under a short photoperiod, which produced the autumnal form with diapause. We found almost no differences in adult spermatogenesis between the two seasonal forms, indicating that adult spermatogenesis is not related to adult diapause. Although adult diapause in the autumnal form is maintained under short photoperiods and terminated under long photoperiods, such a photoperiod did not affect the spermatogenesis of the autumnal form. Our earlier studies indicate that relatively few eupyrene and apyrene sperm are produced after overwintering. Although apyrene spermatogenesis occurred in young adults, eupyrene spermatogenesis did in a small scale before overwintering. These results suggest strongly that male autumnal form butterflies prepare the sperm until overwintering, which had been formed during the larval, pupal and young adult stages.

Quantitative response to photoperiod and weak coupling between seasonal morphs and diapause regulation in the Asian comma butterfly, Polygonia c-aureum (Lepidoptera: Nymphalidae)

Reproduction and wing patterns (shape and colouration) in Polygonia c-aureum L. (Lepidoptera: Nymphalidae) are regulated by both photoperiod and temperature experienced during the immature stages, which result in the development of summer or autumn forms. The critical day length for this seasonal change in form was 13.5L : 10.5D at 21°C and 13L : 11D at 25°C. We investigated the connection between seasonal form and female reproduction. Under a 15L : 9D photoperiod at 21°C, reproductively active summer form butterflies are produced, whereas under an 8L : 16D photoperiod at 21°C autumn form butterflies with a strong tendency to enter diapause were produced. On the other hand, under the critical day lengths at 21 or 25°C, autumn form butterflies developed with a weak tendency to enter diapause. When the adult butterflies were transferred from a critical or a short photoperiod to a long photoperiod shortly after emergence, the former were more likely to terminate diapause than the latter. If individuals are reared throughout their entire life cycle under a short photoperiod at 21°C, all the adults have a strong tendency to enter diapause. These results reveal the quantitative effects of photoperiod on diapause in this butterfly and strongly indicate that the determination of the autumn form and induction and maintenance of diapause are not rigidly coupled, at least under laboratory conditions.

Field and Laboratory Studies on the Ecology, Reproduction, and Adult Diapause of the Asian Comma Butterfly, Polygonia c-aureum L. (Lepidoptera: Nymphalidae).

Adult diapause and reproduction of a nymphalid butterfly, Polygonia c-aureum L., were investigated in field and laboratory examinations. Laboratory studies showed that old virgin male butterflies of non-diapausing generations had heavy accessory glands and simplex, which were suppressed in diapausing generations. The number of eupyrene sperm bundles in the duplex increased with adult age, whereas testis size decreased with age. Field examinations indicated that reproductive development of both sexes of diapausing generations in autumn was suppressed, and developed in spring. We attempted to estimate the physiological age of wild-caught males, as adult male age can be estimated from the testis size. We also attempted to determine whether or not wild male butterflies had mated from the development of the accessory glands and simplex, as well as the number of eupyrene sperm bundles in the duplex, by comparing unmated males with mated males. Field examinations suggest that almost all females in a population of non-diapausing generations mated and showed a tendency toward polyandry, while in the diapausing generation, in spring, monoandry rather than polyandry predominated. This suggests a different mating strategy between non-diapausing and diapausing generations.

Effects of photoperiod, temperature and aging on adult diapause termination and post-diapause development in female Asian comma butterflies, Polygonia c-aureum Linnaeus (Lepidoptera: Nymphalidae).

Polygonia c-aureum females exhibit photoperiodically induced imaginal diapause, characterized by cessation of ovarian development. Females grown at a short daylength (SD) entered imaginal diapause, whereas those grown at a long daylength (LD) produced eggs rapidly after adult emergence at 21°C. The termination of diapause was influenced by daylength: diapause ended faster at LD than SD. Complete termination of diapause took 30 days in unchilled females reared under LD at 21°C. On the other hand, prompt, synchronized and strong diapause termination occurred at post-chilling periods. Photoperiods at post-chilling periods affected ovarian development, when the length of pre-chilling periods or the length of chilling periods was shorter, suggesting that these treatments were not enough to complete diapause development. Ovarian development proceeded earlier in chilled and subsequent warmed females than unchilled females. Wing damage was remarkable at post-chilling periods when females were reared under an adequate length of pre-chilling and chilling periods, especially comparing with females under pre-overwintering conditions without chilling, indicating that post-diapause reproductive development was weak in unchilled females. Thus, exposure to low temperatures is necessary for a strong diapause termination in this butterfly.

The complete mitochondrial genome of comma, polygonia c-aureum (Lepidoptera: Nymphalidae: Nymphalinae)

The mitochondrial genome (mitogenome) of Polygonia c-aureum (Lepidoptera: Nymphalidae: Nymphalinae) is determined to be 15,209 bp in length and shows AT bias (80.6%). Similar to other butterflies, it contains 37 typical mitochondrial genes and one AT-rich region (D-loop). All protein-coding genes (PCGs) started with ATN, except for cox1 gene with CGA(R), which is often found in other butterflies, and seven PCGs harbour the typical stop codon TAA, whereas cox1, cox2, nad3, nad5, nad4 and nad1 end with a single T. The rrnL and rrnS genes are 1332 bp and 773 bp in length, respectively. The 342 bp AT-rich region contains non-repetitive sequences, but harbour several features common to the lepidopterans, including the motif ATAGA followed by a 19-bp poly-T stretch and a microsatellite-like (TA)8 element preceded by the ATTTA motif. The complete mitogenome sequence provided here would be useful for further understanding the taxonomy and phylogeny of Nymphalinae.

Effects of juvenile hormone analogue (methoprene) and 20-hydroxyecdysone on reproduction in Polygonia c-aureum (Lepidoptera: Nymphalidae) in relation to adult diapause.

We investigated the effects of juvenile hormone analogue (methoprene) and 20-hydroxyecdysone on female and male reproduction in a nymphalid butterfly, Polygonia c-aureum. This butterfly has a facultative adult diapause controlled by the corpora allata and brain. Methoprene seems to terminate reproductive diapause, although transplantation experiments indicate that the activity of the corpora allata does not affect male mating behavior Endo (Dev Growth Differ 15:1-10, 1973a), suggesting that the brain may be involved in diapause. We found that exposure to methoprene promoted the development of ovaries and of the male accessory glands and simplex. On the other hand, exposure to 20-hydroxyecdysone did not promote the development of female and male reproductive organs and eupyrene sperm movement from the testis to the duplex in the adult stage. Ecdysteroid titer in both sexes was consistently low in adults. These results suggest that imaginal diapause is largely regulated by juvenile hormone in this butterfly.

Effects of pre-overwintering conditions on eupyrene and apyrene spermatogenesis after overwintering in Polygonia c-aureum (Lepidoptera: Nymphalidae)

Sperm polymorphism is widely known in invertebrates. In insects, Lepidoptera has two types of sperm: nucleated eupyrene (fertile) sperm and anucleated apyrene (unfertile) sperm. These sperm types are produced during post-embryogenesis, and eupyrene spermatogenesis precedes apyrene spermatogenesis. During overwintering, spermatogenesis stops and a portion of undifferentiated-stage spermatocytes degenerate. After overwintering, spermatogenesis restarts with unaffected spermatogonia. However, how new spermatozoa arise in the adult testes after overwintering is not known in Lepidoptera. In this study, we investigated the spermatogenesis events in the nymphalid butterfly Polygonia c-aureum after overwintering under various environmental conditions. Our results indicate that both eupyrene and apyrene spermatogenesis restart at any stopping stage and sperm of these types are regenerated in no particular order after adult insect overwintering. This suggests that the spermatogenesis occurring after overwintering proceeds without embryogenetic restrictions related to the developmental sequence.

Effects of photoperiod on the testis fusion in the Asian comma butterfly, Polygonia c-aureum Linnaeus (Lepidoptera: Nymphalidae)

The progress of testis fusion in the immature stages ranging from the 4th larval instar larvae to the pupae in Polygonia c-aureum was compared between two photoperiods (short-daylength and long-daylength). In this butterfly, imaginal diapause induction is controlled mainly by photoperiod and temperature during the immature stages. The study investigated the relationship between the imaginal diapause and testis fusion. The results showed that photoperiod did not exert significant effects on the process of testis fusion, indicating that testis fusion does not relate to the imaginal diapause. A pair of testes fused to a single testis during the prepupal stage and testis torsion occurred shortly after pupation. However, though in rare cases, a few male adults which had been reared in the laboratory and caught in the field had two testes, suggesting no occurrence of testis fusion during the prepupal stage.

A study on selection of Butterfly and Plant Species for Butterfly Gardening

Various types of parks such as ecological park, dragonfly park, etc. are tried to design in order to resolve different environmental issues in urban areas. Parks are considered organism habitats that not only improve the biodiversity but also give people a chance to observe living organisms in urban area. This study was conducted to select basic materials for planning a butterfly garden through reference reviews. The following 21 species of butterflies belonged to 1 order, 4 families, and 16 genera were selected: Phengaris teleius, Pseudozizeeria maha, Thecla betulae, Argynnis hyperbius, Dichorragia nesimachus, Hestina assimilis, Polygonia caureum, Sasakia charonda, Vanessa cardui, Vanessa indica, Boloria selene, Byasa alcinous, Papilio machaon, Papilio macilentus, Papilio protenor, Papilio xuthus, Papilio bianor, Sericinus montela, Colias erate, Eurema hecabe, and Pieris rapae. 85 species belonged to 22 families, 59 genera, 74 species, 10 varieties, and 1 subspecies were selected for host and nectar plants for butterflies selected above. These results would be expected to useful in butterfly gardening. After that, we think it is necessary to be applied these study results in field. This study requires a test in the butterfly garden. The test results will be make the butterfly-plant matrix.

Comparison of Butterfly Communities between Guryongryeong and Gojigkyeong of the Baekdudaegan Mountain Range and the Changes in Their Distribution

The Baekdudaegan Mountain Range is home to a wide range of organisms inhabiting the Korean Peninsula. This study monitored butterfly communities of Guryongryeong (Myeonggye-ri) and Gojingkyeong (Seobyeok-ri) from April to September in 2013 to 2014, and the results were compared with previous data to determine changes in their distribution. We found 1,098 butterflies of 65 different species in Myeonggye-ri, and 1,161 butterflies of 63 different species in Seobyeok-ri. Comparing the two regions, 13 species appeared only in Seobyeok-ri and 15 species appeared only in Myeonggae-ri. When species were ranked according to number of individuals, the top species three species were as follows: Artogeia melete (127, 11.6%), A. napi (100, 9.1%), and Papilio maackii (90, 8.2%) in Myeonggye-ri; and Libythea celtis (146, 12.6%), A. napi (134, 11.5%), and Polygonia c-aureum (69, 5.9%) in Seobyeok-ri. The number of species with fewer than three individuals each was 24 in Myeonggye-ri and 23 in Seobyeok-ri, accounting for a high percentage among the total number of species. The similarities between the two regions were relatively high, and many of the butterflies are on the Red List of Korea. Compared with previous distribution data, there were no significant changes. This consistency indicates that the butterflies of the Baekdudaegan Mountain Range have been conserved well, and therefore the continuity in the Baekdudaegan Mountain Range is necessary to keep in the big picture.

Uptake of liquid from wet surfaces by the brush-tipped proboscis of a butterfly.

This study investigated the effect of the brush-tipped proboscis of the Asian comma (Polygonia c-aureum) on wet-surface feeding. The tip region of this proboscis was observed, especially two microstructures; the intake slits through which liquid passes into the proboscis and the brush-like sensilla styloconica. The sensilla styloconica were connected laterally to the intake slits in the tip region. The liquid-feeding flow between the proboscis and the wet surface was measured by micro-particle image velocimetry. During liquid feeding, the sensilla styloconica region accumulates liquid by pinning the air-liquid interface to the tips of the sensilla styloconica, thus the intake slit region remains immersed. The film flow that passes through the sensilla styloconica region shows a parabolic velocity profile, and the corresponding flow rate is proportional to the cubed length of the sensilla styloconica. Based on these observations, we demonstrated that the sensilla styloconica promotes the uptake of liquid from wet surfaces. This study may inspire the development of a microfluidic device to collect liquid from moist substrates.

Changes of butterfly communities after forest fire

Fires change the diversity and composition of insects in forest ecosystems. In the present study, we examined the change of butterfly communities after a fire including the increase of butterfly richness, grassland species, and generalist species, and more changed communities. Butterflies were surveyed for 5years after the big Uljin fire in 2007. During each year, butterflies were counted monthly by the line transect method from April to October at two sites (burned vs. unburned, ~1.5km routes). Specialist grassland species decreased in the year of the fire but generalist species did not increase significantly. Butterfly richness did not change but butterfly diversity decreased due to a sudden increase of a species, Polygonia c-aureum. The butterfly community in the year of the fire was different from those in later years, showing temporary change of community in the year of the fire. Species composition was significantly different between burned and unburned sites, but this phenomenon cannot be interpreted as an influence of fire due to highly variable species composition of local butterfly assemblages and the non-repetitive sampling site of the present study.

우리나라 주남습지 지역의 육상 곤충상

경남의 대표적 습지인 주남습지를 구성하는 주남저수지, 동판저수지, 산남저수지와 인근의 인공 연꽃단지에서 2010년 5월부터 10월까지 육상 곤충상을 조사하고 군집특성을 분석하였다. 네 곳에서 총 12목 85과 268종, 5,730개체가 조사되었다. 조사된 종 수는 딱정벌레목 63종, 나비목 60종, 노린재목 37종 순이었다. 총 조사된 곤충 수에 대한 목별 개체수의 비율은 딱정벌레목 25.9%, 잠자리목 22.3%, 나비목과 메뚜기목이 각각 15.4%와 12.7% 이었다. 조사 저수지별로는 주남저수지에서 175종, 동판저수지에서 197종, 산남저수지에서 154종이 조사되어 비슷한 양상을 보였으나 인공 연꽃단지에서는 86종이 조사되었다. 조사된 4곳의 곤충상을 요약하면 딱정벌레목에서는 일본잎벌레, 잠자리목에서는 고추잠자리, 나비목에서는 네발나비가 우점종이었다. 조사 전(全) 기간에 대한 종다양성 지수를 분석한 결과, 우점도 지수는 인공 연꽃단지가 0.25로 가장 높았고 주남저수지가 0.08로 가장 낮았다. 다양도 지수는 주남저수지가 4.48, 동판저수지가 4.44, 산남저수지가 4.28, 인공 연꽃단지가 3.87로 모두 높은 편이었다. 각 습지의 곤충상 유사도를 분석한 결과 주남저수지와 동판저수지의 유사도가 0.96으로 가장 높았으며, 세 곳 저수지와 인공 연꽃단지의 유사도는 0.45~0.53으로 낮은 편이었다. Terrestrial insect fauna was surveyed in the Junam wetland area, which consists of the Junam, Dongpan, and Sannam wetlands, by visual counting and pictures. A sweep net collection was conducted from May to October 2010. A neighburing artificial lotus wetland was also surveyed for comparison. A total of 5,730 insects were surveyed, representing 268 species in 85 families and 12 orders. Sixty-three species of coleopterans were surveyed, followed by 60 species of Lepidoptera, and 37 species of Hemiptera. Coleopteran individuals were 25.9% of the total insect numbers surveyed, comprising most abundant group. This was followed by Odonata, Lepidoptera, and Orthoptera at 22.3%, 15.4%, and 12.7%, respectively. In total, 197 species were surveyed in the Dongpan wetland, 175 in the Junam wetland, and 154 species in the Sannam wetlands. However, only 86 species were surveyed in the artificial lotus wetland. Galerucella nipponensis in Coleoptera, Crocothemis servilia mariannae in Odonata, and Polygonia c-aureum in Lepidoptera were the most abundant in all four wetlands. Community analyses showed that the dominance index was highest in the artificial lotus wetland at 0.25 and lowest in Junam wetland at 0.08. Diversity indices were relatively high in all wetlands at 4.48, 4.44, 4.28, and 3.87 in Junam, Dongpan, Sannam, and the artificial lotus wetland, respectively. The insect fauna similarity index was highest in the Junam and Dongpan wetlands at 0.96. The lotus wetland showed the lowest similarity of the three wetlands with values of 0.45-0.53.

20세기말 남한의 대표적 곤충상

Total insects listed in 166 survey reports of Korean insect fauna for 30 years, from 1971 to 2000, are 4,393 species belonging to 301 families of 17 orders. Based on them, I examined the data of Korean fauna and present the list of Representative Insects in South Korea. A standard of representative species was decided on high frequency of appearance, 50 percent of high rank, whenever surveyed and collected in the field work. As a result, three species, Eristalis tenax(Diptera), Ammophila sabulosa(Hymenoptera) and Polistes snelleni(Hymenoptera) were the most representative species: E. tenax appeared with ratio of 96 percent and A. sabulosa, P. snelleni appeared 95 percent among Collected Chance. Also following four species were the representative species, with appearance of ratio of 90 percent: Atractomorpha lata(Orthoptera), Coccinella septempunctata(Coleoptera), Eristalis cerealis(Diptera) and Polygonia c-aureum(Lepidoptera). Although there were distributed many common species, they would not selected representative owing to the bias of researcher and collecting. Therefore, the result of this study is still highly fluid, and this trend will be apply to the list of Life Style. Additionally, the species list of Extinct Level in th Wild and Endangered or Prosperous in this period are presented here, based on some report and author

도시하천의 계절별 야생동물 서식 연구 - 춘천시 공지천을 대상으로 -

The purpose of this study is to analyze seasonal distribution of insects, birds, fishes, and benthos for Gongji stream in Chuncheon and to explore some strategies towards creating a desirable close-to-nature stream. The number of species occurred in the study stream was 23 for butterflies and 149 for other insects, 23 for birds, 15 for fishes, and 47 for benthos. The study stream was dominated by Artogenia rapae, Polygonia caureum, Cyntia cardui for butterflies, and Passer montanus, Anas crecca, Anas platyrhynchos for birds. The dominant species were Rhynchocypris oxycephalus, Zacco plutypus, Carassius auratus for fishes, and Limnodrilus sp. 2, Chiranumus sp. 2, Hydropsyche KUb for benthos. Attracting insect species of higher density requires planting of host plant species and stabilization of plant coverage against disturbances. To enhance species diversify and density of birds, it is desirable to provide diverse habitats including preservation of downstream wetland and natural vegetation, creation of sand bars and islands with sand and gravel, and restriction or traffic passing and parking. Restoring fish and benthos habitats needs improvement of water quality, layout of gravels and stones on sand-dominant streambed, and use of close-to-nature revetment techniques.

Sperm reflux and its role in multiple mating in males of a butterfly Polygonia c-aureum Linnaeus (Lepidoptera: Nymphalidae)

The relationship between sperm quantity in the duplex and that in the vasa deferentia was examined in the Asian comma butterfly, Polygonia c-aureum. In virgin males, the number of eupyrene sperm bundles in the duplex increased linearly with age, whereas that in the vasa deferentia was consistently small. However, numerous sperm were found in the vasa deferentia of males immediately after mating. The number of eupyrene sperm bundles in the vasa deferentia after mating significantly increased with age and with increasing the time interval between matings. From these and other results, it was suggested that some sperm in the duplex were moved back to the vasa deferentia during mating, and that such sperm reflux provides a means to save sperm for multiple mating.

Effects of Environmental Conditions and Aging on Eupyrene Sperm Movement in Male Adults of Polygonia c-aureum (Lepidoptera: Nymphalidae)

The effects of temperature, photoperiod and aging on eupyrene sperm movement from the testis to the duplex in Polygonia c-aureum male adults were examined in relation to seasonal form and imaginal diapause. In males of both summer and autumn forms obtained under long-day and short-day conditions, respectively, the number of eupyrene sperm bundles in the duplex increased linearly with age during the early stage of adult life at 21 degrees C, and no marked difference was observed between the two seasonal forms. Photoperiod during the adult stage did not influence the rate of sperm movement in autumn forms with diapause. The lower the temperature, the smaller the number of sperm bundles moved from the testis to the duplex. Sperm movement did not appear to occur during a period of chilling at 5 degrees C. Males of the autumn form which were pre-incubated for 30 days and chilled for 60 days failed to resume rapid sperm movement at the final incubation temperature of 21 degrees C. Those which were pre-incubated only for 15 days at 21 degrees C had much fewer sperm bundles in the duplex after chilling than those pre-incubated for 45 days. These results suggest the possibilities that eupyrene sperm movement is suppressed strongly during and after overwintering in the field, and that the eupyrene sperm to be used for reproduction in spring are transferred from the testis to the duplex before overwintering.