Sociobiology: Volume 51, Number 2, 2008

Feature Articles:

Colony Genetic Organization, Fusion and Inbreeding in Reticulitermes flavipes from the Midwestern U.S.

By Christopher J. DeHeer & Shripat T. Kamble

ABSTRACT

Several studies have documented that colonies within subterranean termite populations display substantial variations in both their spatial and genetic organization. In our study, we used microsatellite molecular markers to characterize the spatial organizations and genetic structure in colonies of the eastern subterranean termite, Reticulitermes flavipes (Kollar) collected from a wooded area in Nebraska. Based on molecular genetic analysis, we grouped termites collected from 18 different feeding sites into seven colonies. The three colonies from which we obtained sufficient numbers of samples to estimate foraging distances all spanned distances exceeding 100 m (106, 180 and 210 m, respectively). We also characterized the breeding system within all 7 colonies, of which five we identified as extended-families (headed by many neotenics), and two we identified as colonies that experienced colony fusion. The unusual spatial and genetic organization of this population make it one of the most extreme populations of R. flavipes studied to date within North America.

KEY WORDS: Subterranean termites, spatial organization, genetic variations

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A New Species of Scuttle Fly (Diptera: Phoridae) Parasitizing an Ant (Hymenoptera: Formicidae) in Borneo

By R. Henry L. Disney & Tom M. Fayle

ABSTRACT

Megaselia insignicauda Disney n. sp. is described from females observed attacking Leptogenys mutabilis F. Smith in Sabah, Borneo.

KEY WORDS: Phorid fly, ant parasite, Borneo

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Efficacy of Commercial Termite Baiting Systems for Management of Subterranean Termites (Isoptera: Rhinotermitidae) in Texas

By Grady J. Glenn, James W. Austin & Roger E. Gold

ABSTRACT

The success of commercial baiting strategies for remedial control of subterranean termites has historically had mixed results, owing to discrepancies in applicator error, pest pressure, and choice of toxicant. For this reason, an independent assessment of two specific active ingredients, and three dispensing mechanisms was evaluated to determine their overall efficacy for remedial control of subterranean termite activity in Texas. FirstLine® (FMC Corp.), Sentricon® with Recruit II® bait (Dow AgroSciences), and Terminate® (United Industries, Inc) systems were evaluated. The time required for foraging termites to locate and initiate feeding on Sentricon® and Terminate® bait stations was approximately one-half the time required to locate and begin feeding on FirstLine®, for both Reticulitermes flavipes and Coptotermes formosanus. The time required for C. formosanus to locate and initiate feeding on all termite baiting systems was approximately one-half the time required for R. flavipes. Significant differences in efficacy between the three baiting treatment systems for R. flavipes were not observed, with a mean efficacy of 84%. Sentricon® achieved efficacy (88%) results with supplemental liquid termiticide treatments. FirstLine® efficacy (80%) and Terminate® efficacy (84%) results required initial and subsequent spot-treatments with liquid termiticides for comparable results. Sentricon® yielded better results in the management of C. formosanus, if augmented with supplementary in-ground and above-ground bait stations. Optimum results were achieved when monitoring of bait stations occurred twice each month, rather than on a monthly monitoring regime.

KEY WORDS: termite baiting, Reticulitermes, Coptotermes formosanus, termites

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Local Genetic Co-Structuring of the Ant Petalomyrmex phylax and its Host Plant Leonardoxa a. africana: No Role for a Sixty Meter River Width in Separating Social Forms

By G. Léotard, E. Defossez, C. Debain, D. McKey, F. Kjellberg & R. Blatrix

ABSTRACT

The ant Petalomyrmex phylax is a protective mutualistic ant associated with Leonardoxa a. africana, a small tree of coastal rainforests of Cameroon. The association has expanded southwards during the last few centuries. Northern colonies of the ant are secondarily polygynous while in southern populations, colonies are strictly monogynous. This shift in social behavior seems to be associated with selection for dispersal along a colonization front. The Lobé river seems to constitute a geographic barrier for the system. In all populations north of the river, many polygynous colonies are observed, while mostly monogynous ones are observed south of the river. As the river flows towards the north-west, populations located close to the coast, but just south of the river, present a social structure mainly observed in more southern populations. We investigated, using microsatellite markers, whether the river constituted a genetic barrier thus explaining the rupture in social structure. For both plant and ant, the river did not appear to be an obstacle. These observations suggest that the distribution of social structure in the ant is not explained by physical obstacles. This distribution may rather reflect the historical dynamics of colonization. We showed also that the pattern of genetic structuring was the same for both plant and ant at a scale of a few hundred meters.

KEY WORDS: ant-plant mutualism, monogyny, polygyny, dispersa

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Maculinea nausithous Exploits Myrmica scabrinodis in Transylvania: Unusual Host Ant Species of a Myrmecophilous Butterfly in an Isolated Region (Lepidoptera: Lycaenidae; Hymenoptera: Formicidae)

By András Tartally, László Rákosy, Tibor-Csaba Vizauer, Marin Goia, & Zoltán Varga

ABSTRACT

Isolated populations of the myrmecophilous Dusky Large Blue butterfly (Maculinea nausithous) occur in Transylvania (Romania). The hitherto unknown host ant specificity of these populations was investigated at two sites, where Myrmica scabrinodis was the only potential host ant found. A total of 107 M. scabrinodis nests were opened in early summer to check for the presence of M. nausithous larvae, and two of them contained overwintered larvae. Our observations suggest that, like the habitat, the host ant of these isolated populations essentially differs from other central European M. nausithous populations studied, which use exclusively Myrmica rubra.

KEY WORDS: host specificity, local host, Maculinea nausithous, myrmecophily, Myrmica scabrinodis, Transylvania

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Density Effect on Alate Wing-drop of Coptotermes formosanus (Isoptera: Rhinotermitidae)

By Shuang-Lin Dong, Lixin Mao & Gregg Henderson

ABSTRACT

Alate wing-dropping in termites is a distinct physiological event that occurs after alate swarming and prior to colony foundation. The factors inducing wing-drop and the underlying mechanism are not clear. In this study, we examined alate density effect on wing-drop behavior in the Formosan subterranean termite, Coptotermes formosanus Shiraki. The alates were collected from two sources, light traps and colonies kept in the laboratory. Alate groups were placed in Petri dishes (60x15mm) at different densities ranging from 1 to 20 per dish. The number of dropped wings and dealates were recorded at 5 time intervals after the initial set-up. The results showed that high alate density inhibited wing-drop behavior. Compared to the 1 alate/dish treatment, the 20 alates/dish density showed significant reductions in dealate percentage at almost all observation times. The inhibitory effects of 3, 5, 7 and 10 alates/dish densities varied with alate populations and observation times. To explore the mode of action of wing-drop behavior, we investigated worker presence (40 workers + 1 alate/dish), soldier presence (10 or 20 soldiers + 3 alates/dish) and dead alate presence (20 dead alates + 3 alates/dish) on alate wing-drop. The results revealed that the presence of workers significantly inhibited alate wing-drop, whereas soldiers and dead alates had no inhibitory effect on wing-drop. This suggests that certain types of physical (such as grooming) and/or chemical interactions among live workers and alates are involved in the inhibition of alate wing-drop behavior in this termite species.

KEY WORDS: alate density, wing-drop behavior, Formosan subterranean termite

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Necrophagy by the Social Wasp Agelaia pallipes (Hymenoptera: Vespidae, Epiponini): Possible Forensic Implications

By T. C. Moretti, P. J. Thyssen, W. A. C. Godoy & D. R. Solis

ABSTRACT

The occurrence of 62 specimens of Agelaia pallipes caught in carrion traps using three types of baits (fish, cow liver and poultry viscera) in three different types of environments (rural, urban and forest area) in seven municipalities in Southeastern Brazil is reported here. This specific necrophagic behavior is discussed, since investigations concerning carrion wasps are scant in literature.

KEY WORDS: swarm-founding wasps, vertebrate carrion, forensic entomology, Brazil

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Building of Extra Cells in the Nests of Paper Wasps (Hymenoptera; Vespidae; Polistes) as an Adaptive Measure in Severely Cold Regions

By Satoshi Hozumi, Sôichi Yamane, & Haruo Katakura

ABSTRACT

A paper wasp that dwells in cold regions, Polistes riparius, shows a behavioral habit of building empty cells around the brood-rearing areas and elongating cells up to twice as long as the body length of pupae. We investigated the thermal effect of the number and the length of cells by using model nests with various numbers and lengths of cells. The relationship between the position of the brood-rearing area and temperature distribution in the comb was also studied in relation to the height of the nest from the ground. When the models were heated from above, the cell temperature was high in the model with a greater number of cells or longer cells. Elongated cells appeared to effectively protect against the wind when the thermal effect of the number and the length of cells was compared. When a specific-size model was heated from below and above along with changing the distance from the floor, the temperature distribution was consistent with a change in the height from the floor, and the temperature distribution was consistent with the position of the brood-rearing area and the height of the model nest from the floor. Finally, we compared the thermoregulation of nests between P. riparius and P. biglumis, which also dwells in cold regions and builds extra cells, and it was concluded that these nesting habits are related to thermoregulation of brood-rearing areas and serve as adaptive measures in cold regions.

KEY WORDS: Nest thermoregulation, Polistes, nest architecture, empty cells, cold climate

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Ant Species Richness in Sand Dune Environments Following Burning (Hymenoptera: Formicidae)

By Fabíola Bonicenha Endringer, Iracenir Andrade Santos, Marcos da Cunha Teixeira & José H. Schoereder

ABSTRACT

This study was conducted in the "restinga" (Sand Dune) of Guriri Island (18°43'S, 39° 45'W), São Mateus, Espírito Santo, Brazil. The aim of this work was to test the following hypothesis: the ant species richness in restinga is higher than in open areas and the effect of burnings on the decrease of this richness is stronger in restinga vegetation than in open areas. The ants were collected through the use of pitfalls in contiguous areas, one of these preserved and the other recently subjected to burning. The samples from both vegetation and open areas were compared, considering preserved areas and burned areas. The estimated richness of ant species through Chao2 was used. This was higher in the preserved restinga vegetation (16.25), followed by the preserved open area (13.25). The same pattern was observed when analyzing the burned restinga (coastal sand dune) forest (37), followed by the burned open area (18). The increase in species richness within the burned areas may be due to the fact that the sampling was conducted 35 days after burning, and possibly during the phase of initial colonization in which the environment favored the appearance of the generalist ant species in the area.

KEY WORDS: ant, communities, disturbance, dune, fire, sand

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Field Assessment of the Resistance of Timber Products to Termite (Isoptera) Damage: Results Can Change With the Amount of Bait Wood

By B.C. Peters, M. Lenz2& J.W. Creffield

ABSTRACT

Whether or not termites initiate damage to timber via the end grain may determine the need for spot-treating the exposed untreated cut ends of envelope-treated softwood framing material. Australian Coptotermes acinaciformis (Froggatt) were field-tested for their ability to initiate feeding via the end grain of timber (35 X 90 mm) treated with a repellent TanalithÒ T envelope. Specimens of commercial radiata pine Pinus radiata D.Don framing timber (untreated) and slash pine Pinus elliottii Englem. (untreated and envelope-treated) were partially clad in fine stainless steel mesh. Clad and unclad specimens were exposed to C. acinaciformis near Townsville, North Queensland, Australia, for four months. Results showed that this species of termite can indeed damage timber via the end grain, including exposed untreated cut ends of envelope-treated material as demonstrated earlier for different populations of C. acinaciformis. Differences between the test conditions in field trials carried out at different times (where C. acinaciformis either did or did not damage timber via the end grain) are discussed. Clearly, outcomes from field studies with preservative-treated materials are dependent upon experimental conditions. Notably, the amount of bait wood (highly termite-susceptible timber substrate) offered in a given method can strongly influence the termite response. Further investigation is required to standardise this aspect of conditions in protocols for the assessment of wood preservatives.

KEY WORDS: envelope treatment, preservation, subterranean termite, Coptotermes, softwood susceptibility, test methods, Australia

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Effect of Rod Tips and Soil Types on the Distribution of Imidacloprid and a Water Soluble Dye Following Subsoil Rodding Application for Subterranean Termite Control (Isoptera: Rhinotermitidae)

By Robert W. Davis & Shripat T. Kamble

ABSTRACT

The effects of soil type (sandy loam and silty clay loam), and rodding tool tip (straight, 360°, 180° [3.8 and 7.6 liters/min]) on the distribution of Premise® 75 (imidacloprid) were studied. Water diluted Premise 75 (0.05% AI, 6.06 liters) was applied to the soils per rodding point with a B&G® rodding application tool (1.22 m) using a constant application pressure (172.4 kPa). No significant differences in imidacloprid distribution resulted from the rodding tip or soil type. In all applications, the largest imidacloprid concentrations were located within 0.15 m of the injection site (>10 µg/g) 0-1.22 m below the soil surface. Generally, lesser termiticide quantities were detected in the soil with an increase in distance from the injection point (0-10 µg/g). Based on these results, rodding hole spacing 15 cm apart will provide sufficient imidacloprid overlap. This will create a continuous soil termiticide barrier from 0.0-1.22 m beneath the soil surface along a structure's foundation for protection from subterranean termites. Rodding spacing of 30 cm will provide a continuous barrier 0.61-1.22 m below the surface, but may result in untreated soil areas between the soil surface and the treated soil (0.0-61.0 m). Important differences in imidacloprid distribution are not expected regardless of the rodding tip selection or these soil types.

The validity of using a water soluble fluorescent dye to estimate the distribution patterns of a termiticide active ingredient in Nebraska soils after rodding also was investigated. Premise 75 (imidacloprid 0.05% AI) and Pylam D&C Green #8 (hidacid uranine 0.5% AI) were concurrently applied. The dye was easier to visually detect in the sandy loam (>83 ppm @ 90% probability) than in the silty clay loam (>143 ppm @ 90% probability). The dye distribution patterns in the soils were similar to those observed for imidacloprid. In the sandy loam, visual dye (>83 ppm) and imidacloprid (>1.00 µg/g) were distributed similarly in 88.8% of the soil samples. In the silty clay loam, visual dye (>143 ppm) and imidacloprid (>1.00 µg/g) were distributed similarly in 83.7% of the soil samples. The dye (visual) may be used as a conservative estimator of imidacloprid (>1.00 µg/g) distribution in the silty clay loam. However, caution should be exercised when using dye in predicting imidacloprid distribution in sandy loam soils since it may overestimate insecticide lateral dispersion.

KEY WORDS: Subterranean termites, imidacloprid, termiticide distribution, dye, soils

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Optimizing Pitfall Sampling for the Detection of Argentine Ants, Linepithema humile (Hymenoptera: Formicidae)

By Margaret Stanley, Darren Ward, Richard Harris, Greg Arnold, Richard Toft & Jo Rees

ABSTRACT

Effective sampling devices and optimized sampling strategies play an important role in the detection of invasive species and monitoring outcomes of pest management. Many ant species, such as the globally invasive Argentine ant, Linepithma humile (Mayr), are transported by human trade activity and establish in new regions. Because of their small size and their cryptic nature, they often go unnoticed upon arrival and survivors are hard to detect when controlled. This study compared the effectiveness of different pitfall trap designs (use of fish oil, Teflon coating on the trap) and trapping durations for the detection of Argentine ants in two urban reserves in Auckland, New Zealand. Detectability differences between pitfall traps and monitoring baits were also evaluated. The probability of detecting the presence of Argentine ants increased sixteenfold with the addition of fish oil. There was no significant change in detection if Teflon was used. The probability of detecting Argentine ants also increased with increasing duration of pitfall trapping. Pitfall trapping, particularly over 4-weeks duration, was consistently better at detecting the presence of Argentine ants than baiting. Optimizing sampling devices can play an important role in the detection of invasive species.

KEY WORDS: Argentine ants, detection, monitoring, pitfall traps, surveillance

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Social Organizational Influences on the Morphologic Differentiation in Polistinae Wasps (Hymenoptera: Vespidae)

By Z. García, C. E. Sarmiento & S. Rojas

ABSTRACT

The relationship between morphologic differentiation of Neotropical social wasp populations and social organization, altitude, climate, and geologic history of the northeastern Andes was studied. Populations of seven species of wasps were chosen as representatives of the two types of social organization, and of distribution in either lowlands separated by mountains, or highlands separated by valleys. Differentiation was detected through both principal component analysis and multivariate analysis of variance of eight body measurements. We found a relationship between morphological differentiation and both altitude and social organization in Vespid populations. There was no evidence that either climate or geologic history are related to the differentiation between Vespid populations. These results are consistent with the low dispersal capabilities proposed for the swarm-founding species and with the theories about Andes colonization. It is possible that social organization may be responsible for the diversification of the group.

KEY WORDS: swarm-founding species, independently-founding species, PCA analysis, morphometric differentiation, population differentiation

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Two New Species of the Melaloncha ungulata Group of Bee-Killing Flies (Diptera: Phoridae)

By Giar-Ann Kung

ABSTRACT

Two new species of Neotropical Melaloncha Brues, belonging to the M. ungulata group, are described: M. annicae from Costa Rica and M. browni from Argentina.

KEY WORDS: Diptera, Phoridae, Melaloncha, new species, Neotropical, parasitoid, Apidae

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Effect of Bait Supplements on the Feeding and Tunneling Behavior of the Formosan Subterranean Termite (Isoptera: Rhinotermitidae)

By Mary L. Cornelius & Weste L. A. Osbrink

ABSTRACT

This study examined the effects of water soluble chemicals from an aqueous extract of Summon Preferred Food Source disks and from a sports drink, GatoradeTM, on the feeding and tunneling behavior of the Formosan subterranean termite, Coptotermes formosanus Shiraki. Both the Summon extract and GatoradeTM significantly increased the rate of tunneling in treated sand. The Summon extract had a stronger effect on the rate of tunneling than Gatorade. In both choice and no-choice tests, there was significantly more feeding on wood blocks in the containers with sand moistened with water than in containers with GatoradeTM-treated sand. Summon extract-treated sand had no effect on consumption of wood blocks. In experiments where sand was dyed with solutions of Nile Blue A, termites were more likely to become blue when sand was dyed with a GatoradeTM/Nile Blue A solution than when sand was dyed with Nile Blue A dissolved in water or in the Summon extract. These results suggest that termites were ingesting the GatoradeTM, but not the Summon extract. Termites were less likely to feed on wood blocks when sand was treated with GatoradeTM, presumably because they were able to obtain some nourishment from the GatoradeTM. Increasing our understanding of how water soluble chemicals influence the foraging behavior of Formosan subterranean termites will enhance our ability to use attractants and feeding stimulants more effectively to improve the efficacy of commercial bait products.

KEY WORDS: feeding, tunneling, attraction, termite baits, wood consumption

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Effect of Parental Environment on Preweaning Growth of Sprague-Dawley Pups

By Nilufer Sabuncuoglu & Omer Coban

ABSTRACT

The objective of this study was to compare preweaning growth of Sprague-Dawley pups in three different parental settings. The settings consisted of (1) a single mother with her pups (solitary breeding), (2) two mothers with their pups (plural breeding) and (3) a single mother with her pups and the presence of a non-lactating sister, serving as a social enhancer and an assistant caretaker for the mother (singular breeding). Pups reared by single mothers and sister assisted-mothers (1 and 3) gained significantly more weight than those in plural breeding units (P<0.05). Alterations in mother weights during lactation were not statistically different. Our findings suggest that solitary and singular breeding result in greater preweaning weight of Sprague-Dawley pups than plural breeding.

KEY WORDS: parental environment, social enhancement, Sprague-Dawley, preweaning growth, singular/plural breeding

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Differential Predation of Soldiers and Workers of Cortaritermes fulviceps (Termitidae: Nasutitermitinae) by Ants (Hymenoptera: Formicidae)

By Isabel C. T. Brandão, Daniela F. Florencio & Elena Diehl

ABSTRACT

The termite neutral castes of the subfamily Nasutitermitinae differ regarding their defense system, thus this work aimed to evaluate if there are differences in the predatory activity of ants on soldiers (with chemical defense) and workers (without chemical defense) of Cortaritermes fulviceps (Silvestri). Tests were carried out using termite-baits (400/caste) pasted on the trunk of Inga marginata (Willd.) Kuntze (Fabaceae), a native tree species. The numbers of individuals of each caste antennated and those removed by the ants were assessed at 15, 30 and 60 minutes after the beginning of the tests. The differences between the number of soldiers and workers antennated by ants were not significant (15 minutes: χ2Yates=0; df=1; P>0.05 - 30 minutes: χ2Yates=0.729; df=1; P>0.05 - 60 minutes: χ2Yates=0.287; df=1; P>0.05). However, significantly more workers than soldiers were removed (15 minutes: χ2Yates=5.224; df=1; P<0.05 - 30 minutes: χ2Yates=5.512; df=1; P<0.05 - 60 minutes: χ2Yates=7.955; df=1; P<0.01). The results suggest that ants discriminate between the neutral castes of the termite, preferably choosing workers. Tests in the laboratory were performed, where a soldier of C. fulviceps and a worker of Crematogaster quadriformis Roger (Formicidae, Myrmicinae) were placed on a mini-dish in order to verify if the soldier threw a frontal secretion toward the ant. Thirty replicas of the test were performed and for each one a control-dish with only C. fulviceps was made . In the treatment group there was a significantly higher number of soldiers releasing the secretion than in the control group (χ2Yates=15.600; df=1; P<0.001), indicating that the ants, and not other factors, such as stress, make this termite release their defense secretion.

KEY WORDS: behavior, Crematogaster quadriformis, chemical defense, Nasutitermitinae, recognition

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