喙尾琵甲（鞘翅目：拟步甲科）形态记述及生物学特性观察

记述了喙尾琵甲Blaps rhynchopetera Fairmaire各虫态特征,观察了其生物学特性.实验种群1月下旬至12月上旬产卵,卵期为8～15 d;幼虫期141～213 d,共9～13龄,第9龄以后,龄期较长;蛹前期8～14 d;蛹期12～24 d.成虫羽化24～92 d后性成熟,开始交配产卵活动,成虫期超过18个月.自然种群在昆明和曲靖1年发生1～1.5代,世代重叠严重;以不同龄期幼虫和成虫越冬,越冬幼虫于次年4月上旬开始化蛹,新羽化成虫于4月下旬至12月上旬交配产卵,成虫全年都能活动、产卵.该虫为夜出型、暂栖性土壤昆虫,喜潮湿阴暗的环境.成虫具有夜出习性、防御性和群聚性.     

沟眶象的生物学特性及行为观察

沟眶象Eucryptorrhynchus chinensis(Olivier)是臭椿林木的主要害虫之一。在宁夏银川地区该虫1年发生1代,世代不整齐,以成、幼虫越冬。卵期7~10d,幼虫共有6龄,化蛹时间为4月下旬至5月和7月下旬至8月上旬,蛹经过10~14d羽化为成虫。成虫主要啃食椿树枝条幼芽和韧皮部,幼虫危害衰弱木,有时危害生长健旺的幼树韧皮部或木质部。成虫具有假死性,喜光,活动高峰在11~17时。雌、雄虫间的单次交配时间可持续10~20min;有重复交配现象,交配的时间间隔大约是20~40min;交配结束后,雄虫仍伏于雌虫背上达20~30min。雌虫蛀孔产卵,每产1粒卵约需15min左右,每雌平均产卵40粒左右。     

THE IMMATURE AND ADULT STAGES OF CALLOCOCCUS LEPTOSPERMI (MASKELL) (HOMOPTERA: COCCOIDEA: ASTEROLECANIIDAE), WITH OBSERVATIONS ON LIFE HISTORY

Abstract
The gall-forming scale insect Callococcus leptospermi was studied in the field to determine its life history and method of distribution on the host plant, Leptospermum sp., previously L. juniperinum (Sm.) Domin (prickly tea tree, Myrtaceae). This paper complements earlier taxonomic studies on C. leptospermi. Until now the adult female has provided most of the available data on the species. Newly described stages include the second instar male, the third instar assumed female and the adult male. The sexually dimorphic first instar and adult female are redescribed. Callococcus leptospermi is ovoviviparous. It is dispersed by migration of second instar larvae from the parent gall to new feeding sites.     

Population dynamics of male-killing and non-male-killing spiroplasmas in Drosophila melanogaster

The endosymbiotic bacteria Spiroplasma spp. are vertically transmitted through female hosts and are known to cause selective death of male offspring in insects. One strain of spiroplasma, NSRO, causes male killing in Drosophila species, and a non-male-killing variant of NSRO, designated NSRO-A, has been isolated. It is not known why NSRO-A does not kill males. In an attempt to understand the mechanism of male killing, we investigated the population dynamics of NSRO and NSRO-A throughout the developmental course of the laboratory host Drosophila melanogaster by using a quantitative PCR technique. In the early development of the host insect, the titers of NSRO were significantly higher than those of NSRO-A at the first- and second-instar stages, whereas at the egg, third-instar, and pupal stages, the titers of the two spiroplasmas were almost the same. Upon adult emergence, the titers of the two spiroplasmas were similar, around 2 x 10(8) dnaA copy equivalents. However, throughout host aging, the two spiroplasmas showed strikingly different population growth patterns. The titers of NSRO increased exponentially for 3 weeks, attained a peak value of around 4 x 10(9) dnaA copy equivalents per insect, and then decreased. In contrast, the titers of NSRO-A were almost constant throughout the adult portion of the life cycle. In adult females, consequently, the titer of NSRO was significantly higher than the titer of NSRO-A except for a short period just after emergence. Although infection of adult females with NSRO resulted in almost 100% male killing, production of some male offspring was observed within 4 days after emergence when the titers of NSRO were as low as those of NSRO-A. Based on these results, we proposed a threshold density hypothesis for the expression of male killing caused by the spiroplasma. The extents of the bottleneck in the vertical transmission through host generations were estimated to be 5 x 10(-5) for NSRO and 3 x 10(-4) for NSRO-A.     

Asynchronous male and female life cycles in the sexually dimorphic, harem-forming isopod Paragnathia formica (Crustacea: Isopoda)

The complex life history of the sexually dimorphic, harem-forming isopod Paragnathia formica Hesse is described, combining published information with new observations. The results of a two-and-a-half year field study, carried out within the animal's saltmarsh habitat, are presented, revealing significant differences in the life cycles of males and females. Settlement to the breeding habitat of final stage male and female larvae, derived from the same annual generation, was recorded at very different times of the year. The total lifespan of males was shown to be twice that of females.
The larvae, temporary ectoparasites of estuarine fish, and the non-feeding, burrow-living adults are described and categorized into several developmental phases, whose numbers were recorded during the course of the study.
The annual production of larvae during a limited period in the autumn, and the subsequent settlement of final stage larval females and males the following year, were monitored. Larval females entered the burrows of adult males in the spring to breed, and died after releasing viviparous broods in the autumn. Larval males settled later in the summer, reaching adulthood in the autumn and overwintering before breeding some 18 months after their birth and dying at the end of the breeding season. Adult males thus bred with females from the next generation. The differences in male and female life cycles led to great seasonal variations in adult sex ratios, a huge winter bias towards males contrasting with a brief excess of females in the summer.     

The ecology and social behaviour of the Neotropical butterfly Heliconius xanthocles Bates in Colombia

The mimicry, population ecology¹, adult behaviour and life cycle of Heliconius xanthocles were studied at two sites in Colombian tropical forest. The results were compared with the known biology of other Heliconius species. H. xanthocles is probably unpalatable and is a Mullerian comimic of some other species. In the Amazon basin H. xanthocles belongs to the 'dennis ray' mimicry ring of the Heliconiini, which includes Eueides tales, H. bumeyi, H. elevatus, H. melpomene and H. erato. In the Rio Negro valley, where the latter species either do not exist or have different mimetic allegiances, the 'clennis-ray' pattern of H. xanthocles breaks down. The adults are pollen-feeders, like other Heliconius. but they also visit other food sources such as bird droppings. During a mark-recapture programme in the Rio Negro, adults were found to be almost entirely restricted to small areas near their foodplant Passiflorapraeacuta. Females were rarer than males, but this was probably due to a behavioural difference between the sexes. The males had a Fisher-Ford survival rate of 0.95 per day and a life expectancy of 19 days. Population size estimates of males were between 11 and 17 individuals. These estimates are lower than, but comparable to those for other Heliconius. Males as well as females visit the larval toodplant, and an adult male was observed hovering over a small group of larvae. The females lav batches of 12–41 eggs. The largest batch (41 eggs) was laid cooperatively by two females. The larvae are gregarious feeders on shoot-tips of Passiflora praeacuta. and all lile stages are described for the first time. Predation on the larvae by a bug is described. The pupa has a distinctive morphology unlike that of other Heliconius. The adult population ecology, mimicry and larval behaviour are discussed.     

温室希蛛的生物学特性观察

温室希蛛Achaearanea tepidariorum在鲁东南沿海地区1年发生2代,但第2代不完整.越冬蜘蛛4月下旬出蜇,5月上旬开始产卵.卵期10 d,幼蛛期320 d,成蛛期76 d,越冬代成蛛寿命更长,雌雄性比为3∶1.成蛛日均食麦蛾4.9 头,是多种害虫的重要天敌.     

Burying Beetle Larvae Discriminate Between Individual Parents and Between Some Classes of Adults

Offspring begging can be triggered by a variety of acoustic, visual or chemical cues from the parents. In many birds, nestlings use information derived from these cues to discriminate between individual parents or different classes of adults. Although begging occurs in some insects, we know very little about discrimination between adults by insect larvae. Here, we examine whether begging larvae in the burying beetle Nicrophorus vespilloides can discriminate between individual parents or different classes of adults. We found that larvae showed no discrimination between male and female beetles, but that they begged more towards breeding beetles than towards non‐breeding ones. These results were robust regardless of whether larvae had been reared in presence or absence of adult beetles, thus suggesting that larval discrimination is based on an innate template that requires no prior exposure to adult beetles. We also found that larvae begged more towards unfamiliar beetles than towards familiar ones, suggesting that they can learn to discriminate between individual parents based on cues about familiarity. We conclude that insect larvae may benefit from discriminating between different classes of adult beetles, as it allows them to lower the costs associated with begging in response to irrelevant environmental cues (costly in terms of wasted effort) and with not begging in response to the presence of caring parents (costly in terms of lost feeding opportunities).     

黑缘红瓢虫生物学特性的研究

黑缘红瓢虫ChilocorusrubidusHope 1年发生 1代 ,以成虫在杂草、石缝中等处越冬 ,为朝鲜球坚蚧DidesmococcuskoreanusBorchs的重要天敌。主要分布在桃树、梅树等树上 ,对朝鲜球坚蚧有很强的控制作用。黑缘红瓢虫主要以幼虫捕食猎物为主 ,其幼虫对朝鲜球坚蚧雌蚧功能反应符合HollingⅡ模型 ,一昼夜最大捕食量为 8头。成虫主要起繁殖和扩散作用     

Redescription and Life History of Contortylenchus brevicomi,a Parasite of the Southern Pine Beetle Dendroctonus frontalis

Larval and adult life stages are described for Contortylenchus brevicomi (Massey) Rühm parasitizing a Mississippi population of Dendroctonus frontalis, the southern pine beetle. Fourth-stage larvae and free-living adult females of this species are identified and described for the first time. The life cycle of C. brevicomi can be reconstructed from this study. The adult female nematode lays eggs in a mature beetle. Larval development progresses within the hemocoel until fourth-stage larvae exit the host. Mating occurs in beetle galleries and only females enter an immature beetle host.     

山东茶褐蓑蛾生物学特性及防治

茶褐蓑蛾MahasenacolonSonan是茶树的主要害虫之一。该虫在山东茶区每年发生 1代 ,以 7龄幼虫越冬。作者于 1 997年起对其幼虫、蛹、成虫及天敌进行了初步研究 ,统计出害虫在各龄期的分布规律 ,并提出了针对性的防治方法。     

应用性外激素监测马尾松毛虫发生数量的初步研究

本研究采用持效期达 3 0天以上的复合橡胶载体的新型诱芯诱捕器对马尾松毛虫进行林间监测 ,发现诱蛾数量与田间调查的幼虫数量有很大的关联性 ,各乡镇每诱捕点平均诱蛾数与 1代、2代幼虫虫株率、平均虫口的变化趋势基本相同     

Life Cycle of the Mulberry Longicorn Beetle,Apriona germari Hope on an Artificial Diet

Mulberry longicorn beetle, Apriona germari, was reared on an artificial diet to investigate its life cycle. Average egg period was 17.95 days. Most larvae pupated at the 8th (33.3%) or 9th (33.3%) instars, but others emerged from the 7th to the 11th instars. The total duration of larval stage from the 1st to the end of the 9th and the 11th instars were 176.2 and 251.5 days, respectively. For terminatiopn of diapause and acceleration of pupation, low temperature treatment at 5°C for 60 days was highly effective. Average pupal period for female and male was 19.3 and 18.4 days, respectively. Average longevity of adults was similar with 40.5 days for female and 44.3 days for male. Mating had occurred from about 10 days after the adult emergence, and then a female adult laid one or two eggs per day. Average number of eggs oviposited by a female was approximately 47.7. Total life span of A. germari, when reared on an artificial diet in the laboratory, ranged broadly from 197.5 days to 331.5 days mainly depending on the larval period.     

Topical application of a plant extract to different life stages of Trichoplusia ni fails to influence feeding or oviposition behaviour

We have previously determined that larval feeding experience with a feeding/oviposition deterrent modified the feeding responses of larvae and oviposition responses of subsequent moths. These behavioural changes were attributed to learning, but the possibility of chemical legacy could not be ruled out. In the present study, we have topically applied a feeding/oviposition deterrent plant extract from Hoodia gordonii (Masson) Sweet ex Decne (Asclepiadaceae) to larvae, pupae, and adults of Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae) to determine whether the feeding response of larvae and oviposition response of subsequent female moths is similarly modified by chemicals applied to the external surface of the insect. Our results indicate that traces of the extract that may be present internally or externally on the larvae do not reduce the feeding deterrent response of larvae. Furthermore, traces of the extract in or on larvae, pupae, or adult moths did not alter oviposition choice of female moths, leading us to discount the role of experience through topical application in this study. The fact that feeding/oviposition choice was only influenced by prior feeding experience of the larvae and not by topical administration suggests that habituation via sensory stimulation through mouthpart chemosensilla is likely a central phenomenon. Continuous exposure of adult moths to the extract over a period of 7 days did not affect the oviposition response of the female moths, ruling out the role of adult experience on host-plant selection in T. ni . To the best of our knowledge, this is the first study to examine the role of experience via topical application of chemicals onto all life stages of the insect except the egg. Chemical legacy may not be playing a role in influencing the oviposition choices of female T. ni moths.     

Lucilia sericata strain from Colombia: Experimental colonization, life tables and evaluation of two artificial diets of the blowfly Lucilia sericata (Meigen) (Diptera: Calliphoridae), Bogotá, Colombia strain

The objective of this work was to establish, under experimental laboratory conditions, a colony of Lucilia sericata, Bogotá-Colombia strain, to build life tables and evaluate two artificial diets. This blowfly is frequently used in postmortem interval studies and in injury treatment. The parental adult insects collected in Bogotá were maintained in cages at 22°C±1 average temperature, 60%±5 relative humidity and 12 h photoperiodicity. The blowflies were fed on two artificial diets that were evaluated over seven continuous generations. Reproductive and population parameters were assessed. The life cycle of the species was expressed in the number of days of the different stages: egg = 0.8±0.1, larvae I = 1.1±0.02, larvae II = 1.94±0.16, larvae III = 3.5±0.54, pupae = 6.55±0.47, male adult = 28.7±0.83 and female adult = 33.5±1.0. Total survival from egg stage to adult stage was 91.2% for diet 1, while for diet 2 this parameter was 40.5%. The lifetime reproductive output was 184.51±11.2 eggs per female. The population parameters, as well as the reproductive output of the blowflies that were assessed, showed relatively high values, giving evidence of the continuous increase of the strain over the different generations and making possible its maintenance as a stable colony that has lasted for more than two years.     

Host sex preferences and transmission success by the water mite Unionicola foili (Acari: Unionicolidae) parasitic on the midge Chironomus tentans (Diptera: Chironomidae)

This study examined whether ecoparasitic larval Unionicola foili exhibited a sex bias when infecting laboratory populations of the host insect Chironomus tentans and whether an association with male or female midges increased the likelihood of larval mites returning to the aquatic habitat. When laboratory populations of C. tentans were exposed to larval U. foili, there was a higher prevalence of mites among female hosts at emergence (17 of 30 males vs. 25 of 30 females infected by mites). However, there was no significant difference in the distribution or abundance of larvae among infected male (mean = 2.3 larvae per host) and female (mean = 2.6 larvae per host) midges. Larval mites parasitizing both male and female chironomids were more likely to return to water than could be expected by chance. Mite larvae infesting female C. tentans were more likely to return to water when female hosts deposited egg masses in water, suggesting that oviposition plays an important role in cueing larvae parasitizing female midges to detach. The mechanism responsible for increasing the likelihood that mites parasitizing male hosts return to water remains unclear. Future studies will address the possibility of parasite-mediated changes in host behavior.     

Precopulatory mate guarding and mating behaviour in the rotifer Epiphanes senta (Monogononta: Rotifera)

Epiphanes senta is a littoral rotifer species that occurs in temporary waters and displays a mating behaviour which has not, to my knowledge, so far been described for monogonont rotifers. Monogonont rotifers show distinctive periods within their life cycle during which mictic females appear. Mictic females produce haploid eggs that develop into males or into diapausing eggs if fertilized. The females of E. senta are mostly stationary on the substrate while males are more active swimmers. If they encounter eggs with female embryos of their own species, they attend them and mate with the hatching female. Experiments showed that males are able to discriminate between male, female and diapausing eggs. They exhibit a strong preference for female eggs that are only a few hours away from hatching compared with eggs in early developmental stages. Further experiments did not show any significant differences in male attendance of mictic and amictic eggs. It is hypothesized that males judge the age of a female egg by sensing a chemical that is produced by the growing embryo and diffuses through the egg shell. The male mating behaviour is similar to precopulatory mate guarding known from arthropods but it lacks the monopolization of the female by the male.     

Natural Populations of Shipworm Larvae Are Attracted to Wood by Waterborne Chemical Cues

The life cycle of many sessile marine invertebrates includes a dispersive planktonic larval stage whose ability to find a suitable habitat in which to settle and transform into benthic adults is crucial to maximize fitness. To facilitate this process, invertebrate larvae commonly respond to habitat-related chemical cues to guide the search for an appropriate environment. Furthermore, small-scale hydrodynamic conditions affect dispersal of chemical cues, as well as swimming behavior of invertebrate larvae and encounter with potential habitats. Shipworms within the family Teredinidae are dependent on terrestrially derived wood in order to complete their life cycle, but very little is known about the cues and processes that promote settlement. We investigated the potential for remote detection of settling substrate via waterborne chemical cues in teredinid larvae through a combination of empirical field and laboratory flume experiments. Natural populations of teredinid larvae were significantly more abundant close to wooden structures enclosed in plankton net compared to empty control nets, clearly showing that shipworm larvae can sense and respond to chemical cues associated with suitable settling substrate in the field. However, the flume experiments, using ecologically relevant flow velocities, showed that the boundary layer around experimental wooden panels was thin and that the mean flow velocity exceeded larval swimming velocity approximately 5 mm (≈ 25 larval body lengths) from the panel surface. Therefore, we conclude that the scope for remote detection of waterborne cues is limited and that the likely explanation for the higher abundance of shipworm larvae associated with the wooden panels in the field is a response to a cue during or after attachment on, or very near, the substrate. Waterborne cues probably guide the larva in its decision to remain attached and settle, or to detach and continue swimming and drifting until the next encounter with a solid substrate.     

Mating and Sexual Communication by Steinernema carpocapsae (Nemata: Steinernematidae)

Entomopathogenic nematodes are lethal insect parasites that reproduce exclusively inside their hosts in nature. Infection decisions made by the free-living infective-stage juveniles have an impact on reproductive success, but it is likely that mating decisions are made by adults while inside their host. We investigated sexual communication between male and female adult stages of Steinernema carpocapsae (Rhabditida: Steinernematidae) to assess whether mating is chemically mediated during the adult stage or results from incidental encounters between adults inside the insect host. To assess chemical communication, we measured the behavioral response of adult male S. carpocapsae to several different potential sources of chemical information. Male S. carpocapsae responded to virgin females only and were not influenced by mated conspecific females, conspecific males, or heterospecific females. These results show that species-specific communication takes place between adult entomopathogenic nematodes within the host cadaver just prior to mating.