Occurrence of Aetalion reticulatum (Linnaeus) (Hemiptera: Aethalionidae) on Dipteryx alata Vogel (Fabaceae) in Minas Gerais, Brazil

The baruzeiro or baru (Dipteryx alata Vogel) is a tree species native to Brazil that is known for its production of edible nuts with high nutritional value. However, little is known about the insects associated with this forest species. Therefore, this study aims to document the occurrence of leafhoppers on baruzeiro trees in the state of Minas Gerais, southeastern Brazil. We therefore examined baruzeiro plants in an afforestation plot at the Universidade Federal de Uberlândia (18°43'33"S; 47°31'31"W) in August 2020, located in the municipality of Monte Carmelo, Minas Gerais. The leafhopper species was identified as Aetalion reticulatum (Linnaeus) (Hemiptera: Aethalionidae). The ant species Camponotus crassus Mayr (Hymenoptera: Formicidae) was found to feed on the honeydew released by leafhoppers, demonstrating facultative mutualism between the species. This is the first report of A. reticulatum on D. alata in Minas Gerais.

Contributions to the knowledge of Neotropical ant-like spiders: Myrmecotypus tahyinandu sp. n. from Bolivian Chiquitano forest, a new country record for M. niger, and indirect evidence for species-specific mimicry (Araneae: Corinnidae: Castianeirinae)

Myrmecotypus tahyinandu sp. n. is described from the Bolivian Chiquitano forest, and M. niger Chickering, 1937 is recorded from Bolivia for the first time. The morphological differentiation among the closely related M. tahyinandu sp. n. and M. iguazu Rubio & Arbino, 2009 is likely attributable to the selection for specific ant mimicry. Adults of M. tahyinandu sp. n. are accurate mimics of the ant Camponotus crassus Mayr, 1862, M. iguazu of C. sericeiventris (Guérin-Méneville, 1838), and M. niger of Dolichoderus bispinosus (Olivier, 1792). This study is the first to identify ant models for morphologically closely related Castianeirinae, providing a promising starting point for future research on ant mimicry.

Comportamento Predatório Incomum de Menemerus bivittatus (Dufour) (Araneae, Salticidae)

Resumo. Neste trabalho, a aranha-saltadora Menemerus bivittatus (Dofour) é registrada como predadora de pupas de formigas Camponotus crassus Mayr. A captura desse tipo de presa foi realizada por meio da execução de um comportamento especializado, conhecido como “snatching”. Aranhas que exibem esse comportamento roubam o material transportado por formigas operárias (presas ou formas juvenis) para se alimentar. No Brasil, registros desse tipo de interação são escassos na literatura. Trata-se do primeiro registro do comportamento “snatching” em ambiente urbano. Unusual Predatory Behavior of Menemerus bivittatus (Dufour) (Araneae, Salticidae)Abstract. In this work, the jumping spider Menemerus bivittatus (Dofour) is registered as a predator of pupae of the ant Camponotus crassus Mayr. The capture of this type of prey was performed by running a specialized behavior, known as "snatching”. Spiders that exhibit this behavior steal the material transported by worker ants (prey or brood) to feed. In Brazil, records of this type of interaction are quite scarce. This is the first record of the snatching behavior in urban environment.

Tree-Dwelling Ants: Contrasting Two Brazilian Cerrado Plant Species without Extrafloral Nectaries

Ants dominate vegetation stratum, exploiting resources like extrafloral nectaries (EFNs) and insect honeydew. These interactions are frequent in Brazilian cerrado and are well known, but few studies compare ant fauna and explored resources between plant species. We surveyed two cerrado plants without EFNs,Roupala montana(found on preserved environments of our study area) andSolanum lycocarpum(disturbed ones). Ants were collected and identified, and resources on each plant noted. Ant frequency and richness were higher onR. montana(67%; 35 spp) thanS. lycocarpum(52%; 26), the occurrence of the common ant species varied between them, and similarity was low. Resources were explored mainly byCamponotus crassusand consisted of scale insects, aphids, and floral nectaries onR. montanaand two treehopper species onS. lycocarpum. Ants have a high diversity on cerrado plants, exploring liquid and prey-based resources that vary in time and space and affect their presence on plants.

Dinâmica Populacional de Pulgão Preto dos Citros (Sternorrhyncha) em Cultivo Orgânico de Tangerina (Citrus reticulata Blanco) em Seropédica-RJ

O pulgão Toxoptera citricida (Kyrkaldy) (Sternorrhyncha) é um potencial transmissor do vírus da tristeza cítrica sendo considerada uma praga importante para a cultura, foi realizado monitoramento quinzenais no período entre outubro de 2002 a outrubro de 2003, com o objetivo de estudar a dinâmica populacional deste afídeo, incluindo predadores e a interação com formigas, em cultivo orgânico de tangerina cv. Poncã, Fazendinha Agroecológica, Seropédica, RJ. A Análise faunística dos formicídeos atendentes e dos predadores, foi através dos índices de diversidade de Shanon-Wiener (H') e Simpson (D), dominância de Berger-Parker (d) e equitabilidade J (e). Os predadores considerados efetivos na redução populacional do Pulgão preto dos citros (PPC) foram Cycloneda sanguinea (L.), Azya luteipes Mulsant e Pseudodorus clavatus (Fabr.), apesar de terem sido registrados oito predadores atacando colônias do PPC. Verificou-se C. sanguinea com maior pico populacional, seguido de P. clavatus e A luteipes. A diversidade e equitabilidade dos predadores foi considerada alta (H'= 0,7979; D =0,9638; e= 0,8836). Atendendo o PPC registrou-se Brachymyrmex sp., Camponotus rufipes (Fabricius) Camponotus atriceps (Fabricius), Camponotus crassus (Mayr), Camponotus clypeatus (Mayr); Crematogaster sp., Solenospis sp., Ectatomma brunneum (Fabricius) e Pseudomyrmex termitarius (Fr. Smith). A diversidade de formicídeos foi considerada mediana pelo valor H' (0,6585) e alta pelo valor D (0,9012). A equitabilidade também foi considerada mediana (e =0,69). A dinâmica populacional de T. citricida é influenciada pela brotação foliar seguido da predação e o atendimento de formigas. Estes dois últimos fatores são antagônicos devido a proteção oferecida pelas formigas ao PPC. Populational Dynamic of Brown Citrus Aphid (Sternorrhyncha) in Organic Cropping of Tangerine (Citrus reticulata Blanco) in Seropédica – RJ Abstract. The aphid Toxoptera citricida (Kyrkaldy) (Sternorrhyncha) is a potential vector of citrus virus tristeza, consider an important pest of the orchard. Was realized bimonthly monitoring between October 2002 and October 2003, with aim of study the populational dynamic this aphid, included predators ant ant-tending, in organic cropping of tangerine cv Ponkan, Fazendinha Agroecológica, Seropédica, RJ. The faunistic analysis of the ant-tending and predators, were realized across Shanon-Wiener (H') and Simpson (D) diversity index's, Berger-Parker dominance (d) and equitability J (e). The predators considered efficient in the populational reduction of brown citrus aphid (BCA), was Cycloneda sanguinea (L.), Azya luteipes Mulsant and Pseudodorus clavatus (Fabr.), although has been registered eight predators attacking BCA colonies. Verified that C. sangiunea obtained the biggest populational peak, following P. clavatus and A. luteipes. The predators diversity and equitability was considered high (H'= 0.7979; D =0.9638; e= 0.8836). Tending BCA, was registered Brachymyrmex sp., Camponotus rufipes (Fabricius) Camponotus atriceps (Fabricius), Camponotus crassus (Mayr), Camponotus clypeatus (Mayr); Crematogaster sp., Solenospis sp., Ectatomma brunneum (Fabricius) and Pseudomyrmex termitarius (Fr. Smith). Ant-tending was considered medium to H' value (0.6585) and high to D value (0.9012). The equitability was considered medium too (e =0.69). T. citricida populational dynamic is influenced to foliar shoot following predation and ant-tending. These two end factors are antagonist due to protection offer to ants at BCA.

Faecal shield of the tortoise beetle Plagiometriona aff. flavescens (Chrysomelidae: Cassidinae) as chemically mediated defence against predators

Larvae of Plagiometriona aff. flavescens carry a structure on their back made of faeces and exuviae, called faecal shield, which may protect larvae against natural enemies. Previous investigations suggested that the nature of such protection was chemical. To test if chemicals found in the faecal shield of Plagiometriona aff. flavescens provided defence for larvae, experiments in the field and in the laboratory (using the ant Camponotus crassus, and chicks Gallus gallus as model predators) were undertaken. Both field and laboratory experiments showed that live larvae with faecal shields, as well as baits treated with faecal shield extracts, were rejected by predators, confirming the chemical nature of this kind of defence.