Volume 58 Number 1


Sociobiology: Volume 58, Number 1, 2011

Feature Articles:


New Species of the Ant Genus Pheidole (Hymenoptera: Formicidae) from Hainan Province, China

By Zhilin Chen, Duoduo Ye, Chunwen Lu & Shanyi ZhouABSTRACT

A new species of the Genus Pheidole Westwood 1839 is described, P. hainanensis sp. nov. The new species is easily distinguished from other congeners from China by the pronotum of both the major and the minor with a pair of blunt spines. It is closely related to P. acantha Eguchi, but differs from the later by pronotal spines triangular, much shorter, petiolar node in profile bluntly rounded at apex, not acute, hypostoma median processes absent, submedian processes distinct, a pair of lateral processes well developed, and postpetiole at least 2.4 times as broad as petiolar node. In addition, it differs from other species with pronotal spines in the Oriental Region by its shorter pronotal spines, and by the smooth and shining first gastral tergite.

KEY WORDS: Hymenoptera; Formicidae; Pheidole; new species; Hainan; China

Return to top


Observed Color Phenomena and Behavioral Abnormalities of Reticulitermes spp. in AWPA E1-09 Standard Laboratory Termite Test

By Todd E. Johnson, Shane C. Kitchens & Terry L. AmburgeyABSTRACT

A standard laboratory termite test was conducted in September of 2010 using termites from a single colony of Reticulitermes spp., gathered in East Central Mississippi. Testing was performed adhering to procedures outlined in the AWPA E1-09 Standard termite test. Wood wafers used in the test were treated with an organosilane compound. Observations of worker termites exposed to treated wood wafers during testing included disoriented, convulsive type movements as well as sluggish behavior. Post mortem observations indicated that some worker termites exposed to treated wood wafers assumed a light pinkish to red color, primarily in the head area extending to the abdomen. The abnormal behavior and post mortem color phenomena observed in this test resemble observations in past studies on the association between termites and the bacterium Serratia marcescens.

KEY WORDS:

Return to top


Ants on Sapling Cecropia in Forest and Urban Areas of Trinidad (Hymenoptera: Formicidae)

By James K. Wetterer & Daniela S. DutraABSTRACT

The mutualism between Azteca ants and Cecropia trees is among the most conspicuous and best-studied ant-plant relationships in the Neotropics. We surveyed ants on 60 Cecropia peltata saplings (1.2-2.0 m) at four forest and two urban sites in Trinidad. Azteca ants inhabited significantly more forest saplings (34/40) than urban saplings (4/20). We found 27 other ant species on the saplings; most were tending phloem-feeding Hemiptera. There were significantly fewer non-Azteca ant species records on forest saplings (0.65/sapling) than on urban saplings (1.65/sapling). Our results confirm earlier findings that the Azteca-Cecropia mutualism is disrupted in urban environments.

KEY WORDS: ant-plant mutualism, Azteca, Cecropia, myrmecophytes, symbiosis, Trinidad, urban ecology

Return to top


Imidacloprid Gel Bait Effective in Argentine Ant Control at Nest Scale

By O. Blight, J. Orgeas, M. Renucci & E. ProvostABSTRACT

The Argentine ant, Linepithema humile, has invaded urban, agricultural, and natural habitats worldwide, causing economic damage and disrupting ecosystem processes. As a contribution to Argentine ant management, the present study aimed to test in situ the efficacy of an imidacloprid gel bait. We tested the gel efficacy in terms of Argentine ant eradication at nest scale, conducting experiments on four nests. We recorded a significant decrease in ant abundance for three of the four study nests and three nests presented no activity 21 days after the first. There were strong assumptions that the decrease in ant abundance and activities was a direct consequence of the use of the gel bait, showing that the use of imidacloprid delayed toxic gel may be effective and an alternative to liquid and solid baits as part of much needed management strategies for this major pest.

KEY WORDS: Linepithema humile; imidacloprid gel; eradication; nest scale

Return to top


Liquid Chemicals for Inhibiting the Damage of Odontotermes formosanus and Macrotermes barneyi (Isoptera: Termitidae) to Trees

By Wan Deng, Aishou Lin Aijuan Yi, Difei Wu, Lianghe Feng, Yunyue Hu, Ying Dong & Jianchu MoABSTRACT

The Objectives of this research were to compare the ability of fenvalerate, ivermectin and fipronil to control the damage of Odontotermes formosanus Shiraki and Macrotermes barneyi Light to trees in Huagaishan Park and Cuiweishan Park, Wenzhou city, Zhejiang province, China during the period of August 2008 to October 2009. The results of irrigating liquid chemicals in the soil around the base of trunks indicated that 0.05%~0.4% fenvalerate solutions and 0.003125%~0.025% fipronil solutions effectively retarded termite attacks on trees. However, 0.0025%~0.02% ivermectin solutions could only repress infestation by O. formosanus and M. barneyi for a shorter amount of time. This information shows fenvalerate and fipronil are preferable to ivermectin for the control of O. formosanus and M. barneyi.

KEY WORDS: Odontotermes formosanus, Macrotermes barneyi, fenvalerate, ivermectin, chemical control

Return to top


Molecular Cloning and Expression Analysis of the Gene Encoding TNI in the Ant Polyrhachis vicina (Hymenoptera:Formicidae)

By Xinjun Guo Gengsi Xi & Jin ChangABSTRACT

Troponin I (TNI), one of the subunits of the troponin complex, plays an important role in regulating muscle contraction. Here, a TnI homolog (referred to as PvTnI) was isolated from the ant Polyrhachis vicina Roger (Hymenoptera: Formicidae). Two isoforms (isoform A and B) of the PvTnI cDNA sequence were obtained. The two sequences of 2074bp and 1793bp in length possess different ORFs of 660bp and 615bp respectively, encoding 219- and 204-amino acid proteins. The deduced proteins possessing highly conserved Troponin domains show high homology with other TNI proteins. Results of real-time fluorescence quantitative RT-PCR show expression levels of different stages change constantly, with distinctly low levels in embryos relative to the following stages, while in the adult ants the PvTnI gene was highly expressed in males compared with workers and females. The results suggest that PvTnI transcripts exist in different developmemtal stages and the expression of PvTnI is developmentally and caste-specifically regulated.

KEY WORDS: molecular cloning, troponin I (TNI), real-time RT-PCR, Polyrhachis vicina

Return to top


Complete Genome Sequence of a Chinese Isolate of the Israel Acute Paralysis Virus

By Hongxia Ai, Xun Yan & Richou HanABSTRACT

Israel acute paralysis virus (IAPV) is associated with colony collapse disorder of honey bees. An isolate of IAPV was detected in China. Its genome was analyzed and compared with other IAPV isolates from different countries. The results revealed that the Chinese IAPV carried a 9482 nt RNA genome in positive orientation, with two open reading frames (ORF 1 and ORF 2) separated by an intergenic region of 184 nucleotides. Blastp analysis of the translated ORF1 recognized conserved domains for helicase, protease, and RNA-dependent RNA polymerase (RdRp). The Chinese isolate exhibited the highest (96.9%) nucleotide sequence identity with the original isolate (EF219380)from Israel across the complete genome. The amino acid sequences of ORF 1 and ORF 2 exhibited highest identities (96.9-98.8% and 97.1-99.0%, respectively) with other isolates (EF219380, EU436423, EU436455, EU436456, EU218534, EU224280, EU224279), which were much higher than the corresponding nucleotide regions (92.4-96.6% and 95.5-97.3%, respectively) within the genome. These data indicated that the nucleotide differences among the IAPV isolates were largely synonymous, suggesting purifying selection pressure on the viral genome. Phylogenetic analysis revealed the existence of three geographically distinct IAPV lineages, the Chinese isolate representing a distinct lineage. Analysis of representatives from each proposed lineage suggested the possibility of recombination events. Whether the differences in the coding sequences of different IAPV isolates implicated their virulence potentials were discussed.

KEY WORDS: Israel acute paralysis virus, Apis mellifera, Phylogenetic analysis, honeybees

Return to top


Efficacy of Several Monitoring Stations to detect Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae)

By Ying Dong, Qingfeng Dai, Jingyang Zhao, Jianqiang Guo, Yuegang Gong, Wan Deng, Li Chen, & Jianchu MoABSTRACT

The subterranean termite Coptotermes formosanus (Isoptera: Rhinotermitidae), an economically important pest species damaging trees and wooden structures, has a wide distribution in cities and rural areas in China. The efficacy of five monitoring stations for the monitoring of this termite activity was tested in four locations which were seriously infested by Coptotermes formosanus in Deqing county and Hangzhou city, Zhejiang province, China. Results showed that every monitoring station tested was useful to monitor the activity of termites. Termites would enter into the monitoring stations to feed on wood blocks within 1~2 weeks after installation of monitoring stations during the season of activity. However, the number of termites entering into a monitoring station to feed was positively related with the total volume of blocks in a monitoring station. Among the five monitoring stations tested, the monitoring stations produced by the Hangzhou Institute of Termite Control and the Shanghai Wanning Pest Control Technology Co., Ltd. trapped much more termites than those produced by the U.S. companies Ensystex Inc. and DowAgro Sciences. The numbers of termites trapped were 3051~8712 and 2038~8684 for the former and 236~503 and 291~522 for the latter. This means the design of a monitoring station has an important effect on the number of termites trapped.

KEY WORDS: Subterranean termites; monitoring station; Coptotermes formosanus

Return to top


Influence of Colony Age on Production and Fecundity of Replacement Reproductives in the Dry Wood Termite Cryptotermes domesticus (Isoptera: Kalotermitidae)

By Zhen-You Huang Xing Qian, Jun-Hong Zhong, Jian Hu, Zi-Qian Li, Qiu-Jian Li & Bing-Rong LiuABSTRACT

Colony age is an important intrinsic factor for differentiation in production of replacement reproductives in termites. We tested the effect of colony age on production and fecundity of replacement reproductives of the dry wood termite Cryptotermes domesticus (Haviland) by culturing different ages of orphaned colonies. No replacement reproductives were produced by 1-year-old orphaned colonies. In contrast, 2.25-year-older orphaned colonies produced a pair of replacement reproductives, but no eggs. 3.25-year-old and above orphaned colonies oviposited functional eggs which can develop into larvae. The results reaffirm that colony age can have important influence not only on replacement reproductive production but also on their fecundity.

KEY WORDS: replacement reproductives, colony age, fecundity, Cryptotermes domesticus, orphaned colony

Return to top


Effects of Natural Infestations of the Mite Varroa destructor on the Development of Africanized Honeybee Workers (Apis mellifera)

By Igor Médici de Mattos & José Chaud-NettoABSTRACT

The mite Varroa destructor (Anderson & Treuman 2000) has caused extensive damage to beekeeping worldwide. In Brazil, weather conditions and the strains of bees do not provide ideal conditions for mite parasitism, which is reflected in the low number of deaths of colonies caused by varroatosis well as the stability of infestation levels. The aim of this study was to evaluate the damage caused by the mite infestation in hives maintained in natural conditions. For this purpose the number of mites per bee was calculated and used to quantify the level of infestation in each colony. To record the mortality rates of parasitized bees during development daily checks were performed. The data were analyzed by G test of independence and a Test of Proportions. The results indicate that the rate of mortality of pupae and larvae was proportional to the degree of infestation in each colony, and all colonies showed mortality rates significantly higher than the control rate. A significant interaction among death rates recorded between the third and fourth days of larval life and the total death of larvae was found (G Test = 50.22; P < 0.0001). So, it can be concluded that bee inbreeding contributed significantly to the increase of the larval rate of mortality. In Africanized honeybee colonies infested by the mite Varroa destructor mortality rates in conditions of natural infestation varied from 6.65 to 9.89% in pupae (= 8.78%) and from 6.13 to 13.48% in larvae ( = 9.91%), against 3.85% and 3.74% in the control colony, respectively. Therefore, in the infested colonies the average rates of mortality caused by the harmful effects of the mite were, respectively, 2.28 times and 2.65 times greater in those two developmental stages.

KEY WORDS: Africanized honeybees, Apis mellifera, Varroa destructor, mortality analysis, development

Return to top


Pathogenicity of Metarhizium anisopliae at Different Concentrations on Cornitermes cumulans (Isoptera: Termitidae)

By Karinelle Lima de Figueiredo, Raimunda Nonata Santos de Lemos, Antonia Alice Costa Rodrigues, Keneson Klay Gonçalves Machado, Priscila Assunção dos Santos, Michela Costa Batista, Aldenise Alves Moreira & Maria Aparecida CastellaniABSTRACT

The use of Metarhizim anisopliae (Metek) Soror in association with other substances for termite control has provided good results, but few studies have attempted to determine the fungus efficiency without these substances. The objective of this study was to evaluate the effect of different concentrations of the pathogenic fungus M. anisopliae (Metsch) Sorok on Cornitermes cumulans. The treatments consisted of suspensions containing 1×105, 1×106, 1×107, and 1×108 conidia.mL-1, in addition to a control (distilled water). Evaluations were performed daily for seven days after inoculation, by counting the number of dead termites. The most effective M. anisopliae concentrations against C. cumulans were 1×106, 1×107, and 1×108 conidia.mL-1, with efficiencies of 54.54%, 56.56%, and 84.84%, respectively, from the fourth day of evaluation. The fungus M. anisopliae showed potential to be used in the biological control of termites.

KEY WORDS: Biological control, entomopathogen, termites

Return to top


Molecular Analysis of Some Chinese Termites (Isoptera) Based on the Mitochondrial Cytochrome Oxidase (CoII) Gene

By Zhou Huang, Xiaoping Chen, Yu Shi, Zhao Shen, Jianxin Peng & Hong YangABSTRACT

Termites (Order: Isoptera) are a group of insects widely distributed in the world. In this study the molecular characters of some termites collected from two different Chinese regions were analyzed based on partial mitochondrial cytochrome oxidase (CoII) genes. In total, CoII genes from 15 different termite colonies were amplified and cloned. The genes were first analyzed by restriction fragment length polymorphism (RFLP) with the restriction enzyme TaqI, and then sequenced. There were 12 different RFLP profiles of CoII genes corresponding to different termite species. CoII gene sequences obtained from the 15 termite colony samples shared 70.2% to 99.8% similarity with each other. Phylogenetic analysis showed that the studied termites belong to the genera Reticulitermes, Odontotermes, Macrotermes, Sinocapritermes; Cryptotermes, Neotermes, and Nasutitermes. The molecular analysis of CoII genes was not only enrich our understanding of termite characters but also give us important insights into the strategy for termite control in the future.

KEY WORDS: Molecular analysis, termites, mitochondrial, cytochrome oxidase subunit II gene, phylogenetic analysis

Return to top


Temporarily Defended Dispersal Area of Alarmed Workers of Solenopsis invicta (Hymenoptera, Formicidae) Provoked by Physical Disturbance

By Y. J. Xu, L. Zeng & Y. Y. LuABSTRACT

The temporarily defended dispersal area (TDDA), i.e., the area around a nest that is defended by worker ants, was described for the fire ant Solenopsis invicta Buren after subjecting them to a major nest disturbance. Two methods were used to calculate this area, a graphical method and a probability theory model method, with no difference found in their respective results. Defensive workers emerged from the nest immediately upon disturbance; their numbers reached a maximum approximately 60-90 s later and then dwindled as workers returned to the nest. The number of defending workers was negatively correlated with the distance from the nest, and the relationship between nest territory and nest mound volume (an indicator of colony size) was found to be logarithmic, indicating that the TDDA increases more slowly than colony size.

KEY WORDS: disturbance, Solenopsis invicta, temporarily defended dispersal area

Return to top


Influence of Environmental Factors on the Foraging Activity of Mischocyttarus cassununga (Hymenoptera, Vespidae)

By Mariana Monteiro de Castro, Daniela Lemos Guimarães & Fábio PrezotoABSTRACT

The social wasp Mischocyttarus cassununga is easily found in the southeast and southern Brazil. However, their foraging behavior is little known. The aim of this study was to examine the foraging behavior and its variation over the seasons. The study was conducted in Juiz de Fora, Brazil, from July/2007 to June/2008. A pre-emergent colony and a post-emergent colony were observed monthly, from 7am to 5pm. The number of wasps that left and arrived to the nest, as well as information about temperature, air humidity, intensity of light and speed wind was recorded. In the rainy season, foraging activity was observed for the whole observation time. This activity was increased in the afternoon. Spearman””””””””””””””””s correlation showed that temperature was the only variable that was positively correlated with departures and multiple linear regression analysis showed that about 50% of departures were influenced by temperature and wind speed. In the dry season, the wasps left the nest later and the flow of individuals was only intense in the middle of the day. The departures showed positive correlation with temperature and humidity (Spearman””””””””””””””””s correlation). Multiple Linear Regression analysis showed that about 70% of exits were influenced by wind speed. Therefore, individual behavior can be influenced by environmental changes that promote activities in the warmer periods throughout the day and seasons.

KEY WORDS: Seasons, social wasps, pre-emergence, post-emergence

Return to top


Life Expectancy and Entropy Values for Workers of Pachycondyla striata (Hymenoptera: Formicidae: Ponerinae)

By Adolfo da Silva-Melo & Edilberto GiannottiABSTRACT

We investigated the life expectancy and entropy value for workers of the ant Pachycondyla striata. Seven nests were excavated and these colonies were raised in laboratory conditions. The workers have a mean life-span of 74.48 days, these have a high mortality rate in the period of 1 to 85 days with a high entropy value of H = 0.611, confirming the number of deaths in the initial period.

KEY WORDS: worker longevity, mortality rate, life table, Pachycondyla striata, Ponerinae

Return to top


Swarming of Termites (Isoptera) in the Mianwali District, Pakistan

By S. Nasir & M.S. AkhtarABSTRACT

Present studies on swarming of termites of Mianwali indicated that no single factor alone was responsible for the initiation of swarming of termites. Instead, a combination of various environmental factors was responsible for swarming and rainfall played a critical role in creating a suitable humidity and temperature combination for flight period. During the period, 83 swarms of eight species of termite were observed. The influence of extrinsic factors on the daily capture rates was analyzed by correlation coefficient and regression. Atmospheric temperature and wind speed turned out to be the main determinants, as humidity remained more or less in the same range and swarming mostly continued in the absence of rainfall.

KEY WORDS: Termite, swarming, atmospheric temperature, relative humidity, rainfall, wind speed

Return to top


Feeding Preference of Coptotermes formosanus and Reticulitermes flaviceps under Laboratory Conditions

By Boris Dodji Kasseney, Jiqian Wei, Tianfu Deng & Jianchu MoABSTRACT

The feeding preference of Coptotermes formosanus Shiraki and Reticulitermes flaviceps Oshima were tested in choice and no choice bioassays with 8 different wood species. Three bait types including solid wood (SW), crude flour (CF) and extracted flour (EF) which was extracted from CF with a mixture of toluene and ethanol were offered to vigorous workers of these two species of termites. Their feeding preferences were determined by bait consumption rate. For SW and CF in both choice and no choice test, C. formosanus and R. flaviceps showed a preference to Liquidamba formosana Hance, Populus bonati Levl, Elaeocarpus glabripetalus Merr, and Magnolia denudate Desr. No clear preference was found in both choice and no choice tests with 8 EF baits. This result suggests that L. formosana could be potentially regarded as a suitable bait matrix in baiting strategies against C. formosanus and R. flaviceps.

KEY WORDS: Coptotermes formosanus, Reticulitermes flavicepes, wood consumption rate, feeding preference, bait type

Return to top


Contributions to the Knowledge of the Myrmecophilous Pselaphines (Coleoptera, Staphylinidae, Pselaphinae) from China. VIII. Myrmicophila tangliangi, a New Genus and Species of Batrisini from Yunnan

By Zi-Wei Yin, Li-Zhen Li & Mei-Jun ZhaoABSTRACT

A new genus and species, Myrmicophila tangliangi Yin & Li gen. et sp. n., collected from a colony of ant Myrmica sp., is described from Yunnan Province, Southwest China. Myrmicophila is formally placed in the subtribe Batrisina, but its systematic position within the subtribe remains uncertain. A detailed description, illustrations of male habitus and diagnostic features of the new taxa are provided.

KEY WORDS:

Return to top


Cytogenetics of Three Melipona Species (Hymenoptera, Apidae, Meliponini)

By Denilce Meneses Lopes, Anderson Fernandes, Milene Miranda Praça-Fontes, Hugo de Azevedo Werneck, Helder Canto Resende & Lucio Antônio de Oliveira CamposABSTRACT

Three species of stingless bees, M. flavolineata, M. fasciculata and M. fuliginosa, were cytogenetically analyzed using conventional staining, C banding and stained with the fluorochromes CMA3/DA/DAPI. The chromosome number was the same for the three species, 2n = 18 (female) and n = 9 (male). The conventional staining and C banding revealed very condensed chromosomes with a high content of heterochromatin, which made it difficult to locate the centromere and visualize the morphology of the chromosomes. The staining with DAPI fluorochrome made it possible to observe that the constitutive heterochromatin consists mainly of AT bases, which are present in great numbers in the chromosomes. The euchromatin was restricted to the chromosomic extremities, being CG positive, as seen by the CMA3 staining. All of the species presented a strongly stained chromosomic pair with the CMA3 indicating a possible relation with the organizing region of the nucleole. Comparing the proposed phylogenetic hypothesis and the distribution of heterochromatic content suggests that the appearance of these characteristics seem to have happened in different moments and more than once in the evolution history of the group, which represents an interesting problem to investigate, requiring additional cytogenetic and phylogenetic studies of the group.

KEY WORDS: stingless bees, Meliponini, C band, fluorochrome, M. flavolineata, M. fasciculata, M. fuliginosa

Return to top


Sex-ratio Bias in Natural Polygyne Colonies of the Red Imported Fire Ant, Solenopsis invicta (Hymenoptera: Formicidae)

By Jing-wen Ye, Yong-yue Lu, Yi-juan Xu & Ling ZengABSTRACT

After a one-year investigation, it was found that there was a serious male bias phenomenon in natural polygyne colonies of Solenopsis invicta Buren in south China. In the Liuyi Area of South China Agricultural University (SCAU), the Wushan Yuejin Area of SCAU, Wasteland in Zengcheng, and Banana Park in Zengcheng, the maximum proportions of nests without female pupae were 40%, 40%, 43% and 33% respectively, while the maximum proportions of nests without male pupae were 17%, 17%, 30% and 17% respectively, without female alates 30%, 30%, 40% and 27% respectively, without male alates 20%, 23%, 23% and 20% respectively. A paired T-test was carried out for comparison for the sum of pupae and alates between male and females. The results showed the male sum was larger than the female, and there were significant differences between them (t=3.37, df= 11, P<0.05). Further, we compared the investment (the gross weight) ratio between male and female alates, and the results showed there was no difference (t=0.49, df= 11, P=0.63).

KEY WORDS: ants, Solenopsis invicta, natural colony, reproductives, sex-ratio bias

Return to top


Immunocompetence and Energetic Metabolism in Different Groups of Workers of Atta sexdens rubropilosa (Hymenoptera: Formicidae)

By Myriam Marques Ramos Ribeiro, Danival José de Souza, Lailla Cristina Gandra & Terezinha Maria Castro Della LuciaABSTRACT

Leaf-cutting ants live in big societies that have a very developed structure and elaborate division of labor. Because different castes are subject to different levels of parasitism, it is expected that workers adjust their innate immune system to minimize fitness loss. We tested for this possibility by measuring encapsulation rate in different groups of Atta sexdens rubropilosa workers: workers of the fungus garden (GARD), foragers (FOR), leaf transporters (LTR), waste transporters (WTR), and waste dwellers (WDL) (those working in waste manipulation). GAR workers, those performing internal activities, exibhited the highest encapsulation rate when compared to other groups, those working outside the colony. Regarding oxygen consumption, no statistical difference was found among the groups, although lower absolute values for GARD workers could indicate lower energy consumption by them, reflecting their low level of activity. Our study indicates that control of diseases in an adult colony of leaf-cutting ants involves changes in innate immune response as workers age and switch tasks.

KEY WORDS: encapsulation, immunity, leaf-cutting ant, respiratory rate, polyethism

Return to top


Effect of Climate Change on Seasonal Foraging Activity of Termites (Isoptera)

By Boris Dodji Kasseney, Jing Li, Jiqian Wei & Jianchu MoABSTRACT

Seasonal foraging activity of termites depends principally on air temperatures which are increasing in recent years due to global warming. To examine the seasonal foraging activity of termites, a walking belt transects of 1 m wide was randomly laid every two weeks in four plots. Inside the frame of each plot, 100 wood logs were examined for the presence or absence of termites during one year. To determine the effect of temperature on termite foraging activity, the relation between the monthly mean temperatures (maximum and minimum) and the termite foraging activity were analyzed. The effect of climate change on this activity was analyzed by comparing our results with a previous study. In our study period, termites foraged throughout all the year. Their activities were low (but occurred) in winter. Foraging increased significantly in summer, reaching a maximum in autumn (especially for Odontoterms formosanus). Odontotermes species were the most active termites in our study sites. The species of this genus attacked 23% of the examined wood logs. Odontotermes dimorphus was also recorded for the first time in Hangzhou. The foraging activity of termites was positively correlated with air temperature. The occurrence of termite activity in winter and the presence of O. dimorphus in our study sites could be a result of global warming. We suggest that any management strategy against termites in these sites should be carried out at the period of high foraging activity.

KEY WORDS: Subterranean termites, foraging behavior, foraging activity, air temperature, belt transect, global warming

Return to top


Technological Needs for Sustainable Termite Management

By Nan-Yao SuABSTRACT

Sustainability of current termite control practices was examined from three perspectives: economic, social and environmental. Soil termiticide treatments, which account for >80% of current subterranean termite control practices in the United States, provide more financial incentives (economic) for the industry than bait treatments, which account for <20% of the market share. While more expensive to operate, bait systems can be used to manage termite populations in a community (social) with less toxic insecticides at smaller quantities (environmental) than soil termiticide treatments. Because the labor expense associated with quarterly site visits for current bait systems is the main reason for the cost difference between soil termiticides and bait systems, there is a need to develop technologies to reduce the frequency of on-site inspections. Electronic sensing and automated monitoring devices have been developed, but the equipment cost prohibits the widespread use of such technologies. A durable bait that protects active ingredient (AI) and bait matrix from degradation is a promising technology that may reduce the annual service frequency to a level comparable to that of soil termiticide treatments so that the “socially” and “environmentally” more sustainable bait technology will become as “economically” sustainable as the soil termiticide treatment.

KEY WORDS: soil termiticide, termite bait, subterranean termite IPM, durable bait

Return to top


Social-Organization Shift in the Sweat Bee, Lasioglossum baleicum (Hymenoptera, Halictidae), Corresponds to Changes in Foraging Activity of the Predatory Ant Tetramorium tsushimae (Hymenoptera, Formicidae)

By Norihiro Yagi & Eisuke HasegawaABSTRACT

Ecological factors, such as predation pressure or survival rate, affect social structure (e.g., gyny or founding modes) in social insects. Multiple females may cooperatively found a nest under severe ecological conditions. In bivoltine sweat-bees, most nests in the first reproductive period include a single female, but nest organization changes to cooperative in the second period. This fact predicts low predation pressures during the first period. However, few studies have examined corresponding changes between nest organization and predation pressures in social insects. Here, we compare the predation pressure between the two reproductive periods by using a sweat bee, Lasioglossum baleicum, that shifts the social organization from solitary to cooperative between the two reproductive periods. We recorded foraging activities of the predatory ant, Tetramorium tsushimae, during the whole reproductive season of L. baleicum and compared those between the first and second periods. The foraging activities of T. tsushimae were low in the first season but rapidly increased with the start of the second season. The foraging activities vary among bee populations depending on temperature conditions. The foraging activities were high during the cooperative period, suggesting that cooperation is a counter strategy to a high risk of predation. Further investigations on relationships between nest organization and strength of predation will bring us deeper insights into the effects of predators on the evolution of cooperation.

KEY WORDS: Halictine bee, Sociality, Cooperation, Predation, Ants

Return to top


Morphology of Richards”””””””””””””””” Gland in the Wasp Metapolybia docilis

By Johan Billen & Fernando B. NollABSTRACT

Richards”””””””””””””””” gland in the epiponine wasp Metapolybia docilis occurs at the anterior side of the 5th abdominal sternite, and is formed by approx. 360 secretory cells. The cells discharge their secretory products through accompanying duct cells into a reservoir that is formed by the invaginated intersegmental membrane between the 4th and 5th sternites. The ultrastructural characteristics of the secretory cells are indicative for the production of a non-proteinaceous secretion, which is in line with the trail substance that is used by these wasps during their swarm-founding.

KEY WORDS: Epiponini, exocrine glands, histology, ultrastructure

Return to top

Bookmark the permalink.

Comments are closed.