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Chemical control of leaf-cutting ants is widely used, but alternative control with toxic plant extracts is promising. Substances with insecticidal potential extracted from plants have numerous ecological advantages. This study evaluated the insecticidal and/or fungicidal potential of the plants Asclepias curassavica (tropical milkweed), Rosmarinus officinalis L. (Lamiaceae) (rosemary) and Equisetum spp. (horsetail) for control of the leaf-cutting ant Atta sexdens rubropilosa Forel, 1908 (Hymenoptera: Formicidae). Forty laboratory-reared colonies of Atta sexdens rubropilosa were used. The plants were collected, dried out in a circulating air oven for 48 hours, ground, and macerated in 96 o ethanol until exhaustion. After filtration, the products were evaporated under reduced pressure to obtain the ethanolic extracts. Acceptance of the reagent, topical application of the extracts, and application of baits containing 4% of the plant extracts were tested. The results showed that all plant extracts tested negatively influenced the development of the fungus garden. Baits produced with Asclepias curassavica caused the highest mortality of the colonies within 7 days. In conclusion, the ethanolic extracts of Asclepias curassavica , Rosmarinus officinalis and Equisetum spp. exhibit insecticidal (contact and ingestion) and fungicidal activity in colonies of the leaf-cutting ant Atta sexdens rubropilosa .

Cyphoderus innominatus Mills, 1938 (Collembola: Paronellidae) was first observed in early colonies of Atta sexdens leaf-cutting ants (Hymenoptera: Formicidae). The colonies were collected on February 6, 2019, from a transition area between the Atlantic Forest and the Cerrado, located in the municipality of Botucatu, São Paulo, Brazil. A total of four colonies collected had an average population density of 227 ± 212 C. innominatus individuals, and most of the latter were found in peripheral areas inside the fungus-garden-growing chamber of the colony. In addition, we observed a possible defensive behavior on the part of workers when C. innominatus individuals were present in the fungus garden chamber. Thus, this is the first record of C. innominatus living in association with early colonies of A. sexdens. Cyphoderus innominatus Mills, 1938 (Collembola: Paronellidae) foi observado pela primeira vez nas primeiras colônias de formigas cortadeiras Atta sexdens rubropilosa , Forel, 1908 (Hymenoptera: Formicidae). Essas colônias foram coletadas em 6 de fevereiro de 2019, em uma área de transição entre a Mata Atlântica e o Cerrado, localizada no município de Botucatu, São Paulo, Brasil. Um total de quatro colônias coletadas teve uma densidade populacional média de 227, de C. innominatus , ea maioria dos últimos foram encontrados em áreas periféricas dentro da câmara de cultivo do jardim de fungo da colônia. Além disso, observamos um possível comportamento defensivo por parte dos trabalhadores quandoC. innominatus estava presente presentes na câmara do jardim de fungos. Assim, este é o primeiro registro de C. innominatus vivendo em associação com colônias iniciais de A. sexdens rubropilosa .

Made available in DSpace on 2018-12-11T17:07:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-09-01 Feeding adaptaton is crucial for the ecological success of animals, which explore specific or varied resources according to the suitability of the selected morphological feature. We hypothesized that the mandibles of leaf-cutng ants exhibit a specializaton because of the specific food preference of some species. The objectve of this study was to highlight possible morphological differences between the mandibles of leaf-cutng ant species of the genus Ata related to food preference, i.e., to investgate the morphofunctonality. A detailed descripton of the mandibles of workers of the grass-cutng ant Ata bisphaerica and of the leaf-cutng ant Ata sexdens rubropilosa was provided. For morphometric analysis, 50 individuals of four size classes were dissected for removal of the right mandible and one sample of each caste was processed for scanning electron microscopy. It was observed differences between species and among castes, demonstratng the clear specializaton of workers. Although the results of mandibular morphometry accept the hypothesis of morphofunctonality, further investgaton is needed taking into consideraton the body size of foragers, robustness and factors that confer greater resistance to the mandibles such as zinc content, the force employed during cutng, and mandibular biomechanics. Faculdade de Ciências Agronômicas UNESP Laboratório de Insetos Sociais-Praga Departamento de Produção Vegetal, Rua Dr. José Barbosa de Barros, 1780 Universidade Federal de Juiz de Fora Faculdade de Ciências Agronômicas UNESP Laboratório de Insetos Sociais-Praga Departamento de Produção Vegetal, Rua Dr. José Barbosa de Barros, 1780

Made available in DSpace on 2018-12-11T16:59:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-01-01 Foraging behavior of leaf cutting ants: How do workers search for their food? Forager ants search for adequate food sources in nature and, after their discovery, they decide whether the source is suitable or not for the colony. However, we asked How do workers seek out the substrate for cultivation of the symbiontic fungus on which they feed? To answer this question, we evaluated the distance traveled by individual workers in the search of food and the distance traveled to return to the nest, as well as the time and velocity necessary for these activities. The results showed that the distance traveled by the leaf cutting ant, Atta sexdens rubropilosa (Linneus, 1758), in the search of food was greater than the distance traveled to return with the substrate to the colony. On the other hand, the mean time and velocity were similar for food search and return to the colony. These results support the hypothesis of information transfer, according to which the worker needs to return to the nest at the beginning of foraging to transfer information to other workers and thus to establish the process of worker ant foraging. It can be concluded that workers travel large distances in a random manner until finding their substrate, but the return to the nest is efficient considering the shorter distance traveled. Universidade Estadual Paulista-UNESP Laboratório de Insetos Sociais-Praga Departamento de Produção Vegetal Faculdade de Ciências Agronômicas, Caixa Postal 237 Universidade Estadual Paulista-UNESP Laboratório de Insetos Sociais-Praga Departamento de Produção Vegetal Faculdade de Ciências Agronômicas, Caixa Postal 237

Made available in DSpace on 2015-11-03T18:06:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-09-01. Added 1 bitstream(s) on 2015-11-04T10:13:23Z : No. of bitstreams: 1 WOS000347152000001.pdf: 685778 bytes, checksum: 637325f071937a239054bc578f4d57fd (MD5) FAPEMA Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Most ants, as leaf cutting ants, construct nests underground to maintain environmental conditions favorable to the development of immature and adult individuals. But there was little works about this, especially doing comparison of nest growth among leaf-cutting ant species. Thus, we studied the growth of nests of the leaf-cutting ants Atta bisphaerica and Atta sexdens rubropilosa from nest foundation until the appearance of a second chamber. To this end, we verified the measurements of the chamber recently constructed by the queen and monitored its growth in the initial phase of nest development. The nests were marked immediately after nuptial flight, with 40 nests of each species being dug at 45, 90, 135, 180, and 225 days afterwards. As a result, it was found a first time statistical demonstration that an ellipsoid chamber shape was verified in both species in the initial chamber at 45 days, and that, after, these chamber became spherical. In general, chamber size increased and format change was found in both species. The depth of the first chamber was found to increase significantly only in A. bisphaerica; this result means that this chamber growths downside rather than upside. The occurrence of a second chamber was verified from six months after nest foundation, in both species. Our study contributes to knowledge of the colony development for up to 1 year, by performing comparison of two leaf-cutting ants species. Univ Estadual Paulista UNESP, Botucatu, SP, Brazil Inst Fed Tocantins, Araguatins, Tocantins, Brazil Univ Estadual Paulista UNESP, Botucatu, SP, Brazil FAPESP: 2008/07032-7 CNPq: 472671/2008-1

Made available in DSpace on 2018-12-11T17:04:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-06-01 The nest dug by the leaf-cutter ant queen of the genus Atta is a vertical tunnel interconnected to a small chamber which holds its offspring and the symbiotic fungus. The depth of the initial chamber of the Atta sexdens rubropilosa ranges from 10 to 30 cm below the soil surface. With this information, we asked whether the ideal initial nest depth is adapted to favorable conditions for the initial colony. We hypothesized this depth can provide a minimum temperature range with almost constant temperature, leading to the development of symbiotic fungus and brood yet to emerge. To test this hypothesis, laboratory experiments were carried out and the soil temperature was measured at different depths. The colony development at different temperatures was studied in the laboratory and the brood production (number of eggs, larvae, pupae and adults) was measured until the first workers emergency. Additionally, lipid content and the survival of queens at different temperatures were determined. Our results show a suitable temperature range (ranging from 24.82±3.14°C to 24.11±1.30°C) at a depth of 5 to 25 cm from the ground, an ideal brood development at temperatures of 24 and 28 °C, and consequently a reduction in lipid content of the queens at high temperatures, without affecting their survival in the trial period. These results indicate that the depth of the initial chamber excavated by the queen is suitable for the success of the incipient colony. Laboratório de Insetos Sociais-Praga Departamento de Produção Vegetal Faculdade de Ciências Agronômicas/UNESP, Caixa Postal 237 Campus Experimental de Itapeva/UNESP Laboratório de Insetos Sociais-Praga Departamento de Produção Vegetal Faculdade de Ciências Agronômicas/UNESP, Caixa Postal 237 Campus Experimental de Itapeva/UNESP