Sociobiology: Volume 44, Number 2, 2004

Feature Articles:


Effects of Multiple Generations of Metarhizium anisopliae on Subterranean Termite Feeding and Mortality (Isoptera: Rhinotermitidae)

By Kimberly M. Engler & Roger E. Gold

ABSTRACT


This research evaluated the attractancy and mortality caused by Metarhizium anisopliae on two species of subterranean termites, Reticulitermes flavipes (Kollar) and Coptotermes formosanus Shiraki. This work was done by testing the mycelium mat matrix of M. anisopliae cultured on rice or corn in an olfactometer and a glass tube bioassay system. The tunneling distances of R. flavipes and C. formosanus, when exposed to aged strains of M. anisopliae, were measured along with the mortality caused by the fungus to populations of the termites. In addition, comparisons were made to determine if R. flavipes were attracted to ethanol extracts of the mycelium of M. anisopliae (X-5), or a commercial preferred feeding product (Summon®). The extracts and the Summon® disks were tested in the laboratory using glass plate bioassays, and in the field using commercial termite monitors containing each of the treatments individually.

The results with attractancy and mortality varied with age and generation of M. anisopliae mycelia, but all treatments were more attractive and caused more mortality than the controls. When presented with choices in the olfactometer, both R. flavipes and C. formosanus showed preference to both the mycelium and the extract forms of M. anisopliae. In the glassplates, the 1:1000 dilution of M. anisopliae extract (X-5) was strongly preferred over the other treatments, and all of the dilutions were preferred over the Summon® and ethanol (40%) treated disks in the laboratory. An analysis of the consumption of test cellulose matrix showed that Summon® did not attract termites, but it was a preferred food source. When the undiluted ethanol extract of M. anisopliae was tested in the field, there were more termite visits to the ethanol extract of M. anisopliae (X-5) treated monitor stations, and the fewest termite visits were observed in the monitors containing the untreated fiber pulp disks.

KEY WORDS: Metarhizium anisopliae, Coptotermes formosanus, Reticulitermes flavipes , attractancy, mortality, age and generational variability

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Changes in the Reproductive Tract of Melipona quadrifasciata anthidioides (Hymenoptera: Apidae, Meliponini) Queen After Mating

By Gustavo Ferreira Martins & José Eduardo Serrão

ABSTRACT


The effect of mating on the morphological features of the female reproductive system of the stingless bee Melipona quadrifasciata anthidioides was investigated as well as the amount of time required for spermatozoa transfer to the spermatheca after mating. Five-day old queens were allowed to mate in the presence of one male. After abandoning the females, the male was analyzed to verify genitalia loss. Fifteen mated queens were obtained and three specimens were dissected in the following periods after mating: 5, 10, 15, 20 and 40 days. For each mated queen analyzed there was another virgin queen used as control. Reproductive systems were extracted with light and scanning electron microscope procedures. Results indicated that mating induced ovarian activity and the increase of the spermatheca wall height. Ovarian activity was asynchronic, but in physogastric queens there was synchronism in oocyte production. Ovarioles in virgin queens were stretched, but after mating an enlargement of the basal portion occurred. Follicle degeneration was frequent and seemed to follow virgin queen aging. Ten minutes after mating we found spermatozoa in the spermatheca. Three hours was the necessary for spermatheca lumen to become filled with spermatozoa.

KEY WORDS: morphology, reproductive system; ovarian activation; stingless bee

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A Method to Trap and Rapidly Segregate Subterranean Termites (Isoptera: Rhinotermitidae) for Laboratory Bioassays

By Menandro N. Acda

ABSTRACT


A simple technique to trap and rapidly segregate large numbers of subterranean termites (Rhinotermitidae) using the jointed stems (culms) of bamboo, is described. The technique separates termites from their natural substrates by placing moist, weathered bamboo culms on top of broken nest debris. Termites immediately migrate from their natural substrates to the dark and moist cavities of the culms allowing rapid collection by tapping out one end onto flat trays when sufficient numbers of termites aggregate in the interior cavities. Field trapping technique involves the use of bundles of weathered, moist bamboo culms placed horizontally along foundation walls or strategic locations in a known area infested with termites. Termites readily feed on the nutrient rich bamboo, aggregate inside the cavities while feeding and then are collected by tapping out one end onto flat trays. This technique provides a fast, inexpensive and efficient method of trapping and segregating tens of thousand of live termites with no or minimal injury.

KEY WORDS: Subterranean termites, Rhinotermitidae, trapping, segregation, bamboo culms

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The Influence of Fruit Morphology and Habitat Structure on Ant-Seed Interactions: A Study with Artificial Fruits

By Rafael Luís Galdini Raimundo, Paulo Roberto Guimarães Jr., Mário Almeida-Neto & Marco Aurélio

ABSTRACT


Artificial fruits designed to simulate lipid-rich non-myrecochorous diaspores were used to test for the effect of fruit morphology and habitat structure on ant-seed interactions in an Atlantic Forest site in SE Brazil. The outcome of the interaction (i.e., if the ìfruitî was removed, cleaned by ants on the spot or had no interaction with ants) and the time of ant response were the investigated variables. Models simulating ìdrupesî and ìarilateî diaspores were used to test for morphological effects and four habitat attributes (litter depth, number of logs, number of trees, and percentage of bromeliad coverage on the forest floor), likely to be correlated with the ant diversity and abundance in the study site, were measured to test for the effect of habitat structure. The proportion of fruits removed or cleaned did not differ between the two morphological models. Sites in which fruits were cleaned had more trees than those in which no interaction occurred. This may be a result of the foraging behavior of arboreal ants that frequently descend to the forest floor to exploit fleshy diaspores. Sites in which model removal occurred had lower litter depth than both those in which models were cleaned and those in which no interaction occurred. A negative correlation was observed between litter depth and ant response time. Accumulation of leaf litter at a given point may have constrained the movements of large ants in general, and ponerine ants (that are important seed removers) in particular. We conclude that that local pattern in litter depth and tree density influence the frequency and outcome of interactions between ants and non-myrmecochorous, fleshy diaspores.

KEY WORDS: seed removal, seed cleaning, Odontomachus chelifer, Pachycondyla striata, Ilha do Cardoso, Atlantic Forest, Brazil

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A Comparative Study of Protein and Enzymatic Activity in Venoms of Some Common Wasps (Hymenoptera: Vespidae) from São Paulo State

By Giselly Pereira da Silva, Márcia R. Brochetto-Braga, Maristela Ruberti, Marcos Lima Ternero & Nivar Gobbi

ABSTRACT


The Hymenoptera Aculeata venoms, with few exceptions, have been poorly studied and characterized. Nevertheless, they have raised increasing interest due to their medical importance, since accidents with these insects are fairly frequent in Brazil and may cause severe allergic reactions. The objectives of the present work were the quantitative characterization of the main allergenic enzymes present in the venom of the species Polybia paulista, Polybia ignobilis, Polistes simillimus, and Agelaia pallipes pallipes through biochemical assays for the determination of total protein content, as well as the level of the enzymatic activity of phospholipase, hyaluronidase, acid phosphatase and esterase. These results, in addition to providing biochemical knowledge about the venom of the species in question, also supply studies that allow phylogenetic inferences among them.

KEY WORDS: Polybia paulista, Polybia ignobilis, Agelaia pallipes pallipes, Polistes simillimus, Vespidae, venom, protein, enzymes

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A New species of Harvester Ant of the Genus Pogonomyrmex (Hymenoptera: Formicidae) from México (in Spanish)

By Miguel Vásquez-Bolaãos & William P. Mackay

ABSTRACT


We describe a new species of harvester ant, Pogonomyrmex humerotumidus from the state of Michoacán, México. The worker of this species is easily recognized, as the psammophore is poorly developed, the mandibles have only 5 teeth, the pronotal shoulders are swollen into protuberances, and the propodeum lacks teeth. The worker is ferrugineous red. The female and male are unknown. It also differs from similar North American species such as P. huachucanus Wheeler, 1914, P. imberbiculus Wheeler, 1902 and P. pima Wheeler, 1909 in lacking propodeal spines. It can be distinguished from P. laevinodis Snelling, 1982, which also lacks spines on the propodeum, as the side of the petiolar node is sculptured, not smooth as in the latter species. It is similar to P. guatemaltecus Wheeler, 1914, which also lacks propodeal spines, but differs in being larger (total length ~ 8 mm, vs. ~ 6 mm in P. guatemaltecus). The pronotal angles of P. guatemaltecus are slightly swollen, but do not form protuberances as they do in P. humerotumidus. In morphology this species is closely related to the Argentinean P. inermis Forel, 1914, which can be distinguished as it has 6 mandibular teeth, and lacks the angulate subpeduncular process.

KEY WORDS: Harvester ant, Pogonomyrmex humerotumidus, Formicidae, Mexico

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Cysts Reabsorption in the Testis of the Bee Wax Pest Achroia grisella (Lepidoptera, Pyralidae) During Spermatogenesis

By F. C. Fernandez & C. da Cruz-Landim

ABSTRACT


The present paper reports the occurrence of testicular cysts degeneration during spermatogenesis of Achroia grisella, a Lepidoptera with dimorphic spermatogenesis, through ultrastrucutural studies. Signs of cysts degeneration can be detected in the last larval instar but it increases during pupation and early adulthood. The degeneration affects the eupyrene, as well apyrene cysts but it is not always possible to recognize which cysts are degenerating. Some morphological features of cysts degeneration resemble apoptosis.

KEY WORDS: Cyst degeneration, eupyrene, apyrene, apoptosis, spermiogenesis

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Review of Remedial and Preventative Methods to Protect Timber in Service from Attack by Subterranean Termites in Australia

By Berhan M. Ahmed, John R. French & Peter Vinden

ABSTRACT


With the phasing out of organochlorine compounds as termiticides in Australia in 1995, consumers and the building industry moved to adopt alternative termite control strategies. These include chemical barriers (organophosphates, synthetic pyrethroids, nicotinoids, and phenyl pyrazoles), physical barriers (graded granite stones, stainless steel mesh) use of termite resistant building materials (metal and plastic termite shields and adhesives), and installing a slab construction that conforms with Australian Standard AS 2870-1996. The latter requires vibration of the concrete during slab formation, regular inspections, preventative action such as keeping garden beds, mulch, or stacked firewood away from exterior walls, or, a combination of all of the above methods.

The use of preservative treatment of timber as a second line of defence has gained momentum in Australia in recent years. This has arisen from the decline in availability of wood species with naturally durable heartwood. Shorter rotations for forest crops and higher quantities of non-durable sapwood and heartwood of species used in construction have accelerated this trend.

Increasingly termite control is adopting integrated pest management (IPM) based on ecological knowledge of termites and minimization of environmental impact of treatments. These include adopting a mix of alternative strategies in termite control that include chemical and physical barriers, and combinations of the same, bait and dust toxicants, treated timber and emphasize building practices that are designed to ëbuild out termitesí and ensure ëwhole of houseí protection of timber in buildings against termites for the reasonable life of the building.

KEY WORDS: Timber in service, attack by subterranean termites

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Problems Experienced by the Los Angeles County Unified School District with Africanized Honey Bees (Hymenoptera:Apidae)

By Hanif Gulmahamad

ABSTRACT


Africanized honey bees, Apis mellifera L. near scutellata Lepeletier (Hymenoptera: Apidae), first arrived in the United States in October 1990 at Hidalgo, Texas. In October 1994, a colony of these bees was discovered in California for the first time near Blythe. This was a result of natural population expansion and migration from Mexico. In April 1999, County of Los Angeles Agricultural Commissioner declared Los Angeles County colonized by Africanized honey bees. Since that time, honey bee work order calls at Los Angeles Unified School District have escalated from 147 in 1998 to 687 in 2003, a 467 % increase. This is probably due to widespread distribution and complete colonization of Los Angeles County by Africanized honey bees. It is postulated that this substantial increase in honey bee calls experienced by Los Angeles Unified School District is due to frequent reproductive swarming and absconding by Africanized honey bees.

KEY WORDS: swarming, Africanized honey bees

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Adelomyrmecini new tribe and Cryptomyrmex new genus of myrmicine ants (Hymenoptera: Formicidae)

By Fernando Fernández

ABSTRACT


Descriptions of Adelomyrmecini new tribe and Cryptomyrmex new genus are made. A key to genera (Adelomyrmex, Baracidris and Cryptomyrmex) is offered, as well as a key for the two known species of Cryptomyrmex, C. longinodus (Fernández & Brandão) comb. n. and C. boltoni (Fernández) comb. n.

KEY WORDS: Adelomyrmecini new tribe, Cryptomyrmex new genus, Key to Genera.

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Sampling Methods for Monitoring the Number and Area of Colonies of Leaf-Cutting ants (Hymenoptera: Formicidae) in Eucalyptus Plantations in Brazil

By José Cola Zanuncio, Efigênio Teixeira Lopes, Hélio Garcia Leite, Ronald Zanetti, Carlos Sigueyuki Sediyama & Maria do Carmo Queiroz Fialho

ABSTRACT


The number and the area of colonies of leaf-cutting ants were evaluated with two sampling methods from May to July 1998 in a Eucalyptus plantation in the Municipality of Montes Claros, State of Minas Gerais, Brazil. The area sampled, the time spent for sampling and the number and area of colonies of leaf-cutting ants were obtained with strips at fixed distances and random sampling. The systematic sampling was performed with nine meters wide strips every 120, 150 or 180 meters besides random allocation of one 720 square meters (9 x 80 meters) plot every five hectares of an Eucalyptus stand. The estimate accuracy for each methodology was evaluated with an F test. Sampling with one strip every 120 meters showed a rate of 2.5 hectares per hour while a random sampling indicated only 0.7 hectares per hour. A strip every 120 meters proved to be most accurate to sample colonies of leaf-cutting ants in Eucalyptus plantations.

KEY WORDS: Eucalyptus, sampling, leaf-cutting ants, Atta

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Catalog of the Fossil Isoptera of the New World

By Luiz Roberto Fontes & Maria Aparecida Vulcano

ABSTRACT


A Catalog on the New World fossil termites, termite ichnofossils and related subjects is presented. The number of taxa registered are: 22 genera (of which 10 are exclusively fossil) and 34 species, 4 ichnogenera and 4 ichnospecies.

KEY WORDS: Fossil termites, new world, review

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Colonial Growth Dynamics of Tropical Urban Pest Ants, Monomorium pharaonis, M. floricola and M. destructor (Hymenoptera: Formicidae)

By Annie G.H. Eow, Alexander S.C. Chong & Chow-Yang Lee

ABSTRACT


Experiments on the colonial growth dynamics of normal, broodless and queenless colonies of three tropical urban pest ants, namely the Pharaohís ant, Monomorium pharaonis (L), M. floricola (Jerdon) and the Singapore ant, M. destructor (Jerdon) were executed in the laboratory. The growth dynamics of M. pharaonis and M. floricola colonies were high, even in the absence of queen or brood. Intrinsic rate of increase (rn) calculated for normal colonies were 0.0233 ± 0.002 and 0.0249 ± 0.001 for M. pharaonis and M. floricola, respectively. In contrast, colonies of M. destructor showed poor growth dynamics in the laboratory, even under normal colony conditions. A further experiment was conducted to determine the minimum egg number required to produce queen(s) in a simulated queenless colony of M. pharaonis and M. floricola. Results indicated that a minimum of 1000 eggs with 100 workers were needed to successfully produce new queens in all replicates for both species. Percentage of queen production was recorded at 0.69 and 0.65% for M. pharaonis and M. floricola, respectively. The numbers of queens produced ranged between 1 and 6 for M. pharaonis, and between 1 and 18 for M. floricola. The mechanism of caste regulation in these tropical household ant species is discussed.

KEY WORDS: ants, Monomorium pharaonis, Monomorium floricola, Monomorium destructor, colony growth, intrinsic rate of increase, caste regulation

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Dominance Hierarchy in Different Stages of Development in Colonies of the Primitively Eusocial Wasp Mischocyttarus cassununga (Hymenoptera, Vespidae)

By Fábio Prezoto, Ana P. P. Vilela, Maria A. P. Lima, Sthefane Díávila, Danielle M. Souza Sinzato, Flávio R. Andrade, Helba H. Santos-Prezoto & Edilberto Giannotti

ABSTRACT


Seven colonies of Mischocyttarus cassununga were studied under field conditions at Universidade Federal de Juiz de Fora, MG, in southeastern Brazil: in pre-emergence, post-emergence and decline stages, during 145.8 hours. Dominance interactions among the females were quantified to verify the dynamics of succession in the social hierarchy of the colonies. Early pre-emergence colonies present more intense aggressive interactions than late pre-emergence ones, because the females are engaged in securing the role of main egg layer in the nest. In post-emergence (pre-male) colonies the dominance hierarchy is more defined and the frequency of dominance and subordination behaviors were lower than in pre-emergence stages: most of the agonistic behaviors are restricted to the first ranked females (potentially queens) and the subordinate individuals play the role of workers in the nests. In the post-emergence, post-male, and decline stages the hierarchy is still maintained by the aggressive behaviors of the 1st-ranked female but because the presence of males and future nest foundresses these interactions are not well defined in a linear way.

KEY WORDS: Hierarchy of dominance, aggressive behaviors, colony stages, Vespidae, Mischocyttarus cassununga

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A New interpretation of the Defense Glands of Neotropical Ruptitermes (Isoptera, Termitidae, Apicotermitinae)

By A. M. Costa-Leonardo

ABSTRACT


Suicidal altruism has been reported for some species of eusocial insects, in which the individual dies in defense of the society. The termites of the genus Ruptitermes are known for the suicidal behavior of the workers which liberate a sticky defensive secretion by body bursting. In the present paper it is given a new interpretation of the defense glands of Neotropical Ruptitermes based on the morphological analysis of three species collected at Rio Claro, SP, Brazil. Before the current study, the suicidal defensive behavior was attributed to the dehiscence of the salivary gland reservoirs. The defense or dehiscent glands of Neotropical Ruptitermes are pair structures rounded in shape that are independent of the salivary glands. The dehiscent glands consist of multiple secretory units that are kept together by thin connective tissue. Each secretory unit is composed of one cell generally with one peripheral nucleus and characteristic secretion. The three species studied here present some histological differences in the secretory units, probably related to the chemical composition of the secretion.

KEY WORDS: defensive behavior, autothysis, termites, salivary glands, dehiscent glands

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Feeding Preferences of White-Footed Ants, Technomyrmex albipes (Hymenoptera: Formicidae), to Selected Liquids

By John Warner & Rudolf H. Scheffrahn

ABSTRACT


Sucrose, fructose, glucose, and maltose in aqueous solutions were offered at selected concentrations in binary choice tests to white-footed ants (WFA) (Technomyrmex albipes) trailing on exterior building walls. Commercial ant baits and four NecDew™ formulae, a proprietary sweet bait, all without toxicants, were also tested against the sugar solutions. WFA foragers preferred NecDew™ to sucrose solutions, and sucrose solutions (≥25%) were preferred over other sugars tested. In tests with solutions containing disodium octaborate tetrahydrate (DOT), NecDew4 with 1% DOT was preferred over a commercial bait with 1% DOT. Additionally, no repellency was observed in 25% sucrose solutions containing up to 7% DOT.

KEY WORDS: sugars, borates, ant baits, NecDew™, Florida

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Method for the Evaluation of Insecticidal Activity Over Time in Atta sexdens rubropilosa Workers (Hymenoptera: Formicidae)

By Nilson S. Nagamoto, Luiz C. Forti, Ana Paula P. Andrade, Maria Aparecida C. Boaretto & Carlos F. Wilcken

ABSTRACT


The active ingredients used in the formulation of toxic baits for leaf-cutting ants (Hymenoptera: Formicidae) should possess a delayed action defined as an insecticidal activity whereby worker mortality is ≤15% at 24 hours and ≥90% at 21 days. Serious shortcomings have occurred in the search for new active ingredients, such as the initial selection of fenoxycarb, copper oxychloride and diflubenzuron, compounds considered very promising but whose inefficiency was verified only later, indicating methodological problems. In view of this situation, we developed a classification method for insecticidal activity over time using workers of the leaf-cutting ant Atta sexdens rubropilosa Forel. The insecticides used were fipronil, sulfluramid GX071HB and sulfluramid GX439, vehicled in an attractive pasty formulation prepared based on citrus pulp. The results obtained were consistent from a toxicological viewpoint and agreed with the literature in terms of the control of colonies. Sulfluramids were found to possess a delayed action at a broad range of concentrations, in agreement with the fact that these substances are highly effective in the control of all leaf-cutting ant species. The smaller range of concentrations of fipronil with delayed action is probably related to its lower efficacy for species more difficult to control such as Atta capiguara (Forti et al. 2003). We discuss the importance of relating behavioral particularities to the specific feeding habits of leaf-cutting ants, with methodological adequacy of the assessment of insecticides aimed at toxic baits.

KEY WORDS: Atta, Acromyrmex, Attini, toxic bait, sulfluramid, fipronil.

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Developmental Pathways and Plasticity of Neuter Castes in Nasutitermes takasagoensis (Isoptera: Termitidae)

By Masaru Hojo, Shigeyuki Koshikawa, Tadao Matsumoto & Toru Miura

ABSTRACT


Caste developmental pathways vary among termite species. We investigated the caste developmental patterns of Nasutitermes takasagoensis, based on morphometric data. These patterns appear to be identical to those of other Nasutitermes species. In addition, a nymph-presoldier intercaste was found during the study. We analyzed the detailed morphology of the intercaste and discuss the developmental plasticity of the caste differentiation in this nasute termite.

KEY WORDS: caste development, intercaste, Nasutitermes takasagoensis

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Grooming Interaction and Reproductive Status Among Queens in Functionally Polygynous Colonies of the Ant Myrmica kotokui (Hymenoptera: Formicidae)

By Tomonori Kikuchi, Noriko Azuma & Seigo Higashi

ABSTRACT


We investigated the behavioral interactions and reproductive status among queens in polygynous colonies of Myrmica kotokui. Reproductive status among queens largely differed and virgin and non-reproductive queens were often observed in the colony with a large number of queens. Reproductive skew positively correlated with the number of queens. Whereas queen-queen aggressive behavior was not seen, allogrooming between queens was observed frequently in six colonies that contained some virgin and non-reproductive queens. In these colonies, some queens were more frequently groomed by nestmates than the others, and rank order based on allogrooming was observed. This rank was correlated with the reproductive status of queens. Rarely-groomed bottom-ranked queens were usually unmated and showed worker-like behavior, while high-ranked queens had yellow bodies in their ovarioles, indicating oviposition experience. However, in the remaining colonies, the relationship was unclear because of the low frequency of allogrooming between queens.

KEY WORDS: reproductive skew, grooming, Myrmica kotokui, polygynous colony

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