Abstract The insect group is one of the most diverse on the planet and due to habitat degradation, many of these species are becoming extinct, leaving a lack of information on the basic biology of each one. In this study, previously unseen information about nesting biology is revealed in Auplopus subaurarius trap nests. This is a solitary ectoparasitoid spider wasp that nests in preexisting cavities. We used a trap-nesting methodology to sample A. subaurarius in two different sampling periods (2017/2018 and 2020/2021) in three types of environment (forest, grassland and Eucalyptus plantation). In our study, the A. subaurarius nest building was more frequent during the hottest months of the year (November to March), with its highest abundance found within natural forest areas and in Eucalyptus plantation than in grassland areas. In addition, the species had two development times: a short one (three months) and a delayed one (up to one year). Moreover, females were larger than males (weight and size) and the species’ sex ratio had a tendency toward female production. Auplopus subaurarius presented seven natural enemy species: Ceyxia longispina, Caenochrysis crotonis, Photochryptus sp.1, Photochryptus sp.2, Messatoporus sp., Ephuta icema and Sphaeropthalma sp. We emphasize the importance of wooded environments to maintain the A. subaurarius populations and their associated interactors, both spiders and natural enemies, as these environments can provide better life conditions than grassland areas. Furthermore, other solitary wasps that may have the same lifestyle of A. subaurarius can also be improved by natural forest conservation and by good silviculture plantation planning, which should consider ecological aspects of Atlantic Forest landscapes.

Resumo O grupo dos insetos é um dos mais diversos do planeta e devido à degradação dos habitats, muitas dessas espécies estão sendo extintas, deixando uma carência de informações sobre a biologia básica de cada uma. Neste estudo, informações inéditas sobre a biologia de nidificação em ninhos-armadilha de Auplopus subaurarius são reveladas. Essa espécie trata-se de uma vespa solitária ectoparasitóide de aranhas, que nidifica em cavidades preexistentes. Utilizamos a metodologia de ninhos-armadilha para amostrar A. subaurarius em dois períodos amostrais diferentes (2017/2018 e 2020/2021), em três tipos de ambientes (floresta, campo e plantação de Eucalyptus). Em nosso estudo, a nidificação de A. subaurarius foi mais frequente nos meses mais quentes do ano (Novembro a Março), com maior abundância encontrada em áreas de floresta nativa e em plantações de Eucalyptus comparados à áreas de campo. Além disso, a espécie apresentou dois tempos de desenvolvimento, um curto (três meses) e um longo (até um ano). Além disso, as fêmeas foram maiores que os machos (peso e tamanho) e a razão sexual da espécie apresentou tendência à produção de fêmeas. Auplopus subaurarius apresentou sete espécies de inimigos naturais: Ceyxia longispina, Caenochrysis crotonis, Photochryptus sp.1, Photochryptus sp.2, Messatoporus sp., Ephuta icema e Sphaeropthalma sp. Ressaltamos a importância de ambientes arborizados para manutenção das populações de A. subaurarius e seus interagentes associados, tanto aranhas quanto inimigos naturais, uma vez que estes ambientes podem apresentar melhores condições de vida comparados à áreas campestres. Além disso, outras vespas solitárias que podem ter o mesmo estilo de vida de A. subaurarius, também podem ser afetadas positivamente pela conservação das florestas naturais e por um bom planejamento de plantações de silvicultura, as quais devem considerar os aspectos ecológicos das paisagens da Mata Atlântica.

Abstract Background: The composition of the venom from solitary wasps is poorly known, although these animals are considered sources of bioactive substances. Until the present moment, there is only one proteomic characterization of the venom of wasps of the family Pompilidae and this is the first proteomic characterization for the genus Pepsis. Methods: To elucidate the components of Pepsis decorata venom, the present work sought to identify proteins using four different experimental conditions, namely: (A) crude venom; (B) reduced and alkylated venom; (C) trypsin-digested reduced and alkylated venom, and; (D) chymotrypsin-digested reduced and alkylated venom. Furthermore, three different mass spectrometers were used (Ion Trap-Time of Flight, Quadrupole-Time of Flight, and Linear Triple Quadruple). Results: Proteomics analysis revealed the existence of different enzymes related to the insect’s physiology in the venom composition. Besides toxins, angiotensin-converting enzyme (ACE), hyaluronidase, and Kunitz-type inhibitors were also identified. Conclusion: The data showed that the venom of Pepsis decorata is mostly composed of proteins involved in the metabolism of arthropods, as occurs in parasitic wasps, although some classical toxins were recorded, and among them, for the first time, ACE was found in the venom of solitary wasps. This integrative approach expanded the range of compounds identified in protein analyses, proving to be efficient in the proteomic characterization of little-known species. It is our understanding that the current work will provide a solid base for future studies dealing with other Hymenoptera venoms.

Abstract In the present study, data on the interaction between wasp specimens of the species Epipompilus platensis Roig Alsina, 2017 (Hymenoptera, Pompilidae) and spiders of the species Ariadna mollis (Holmberg 1876) (Araneae, Segestriidae) are presented for the first time. Present in the localities of Punta Lara (Partido de Ensenada) and José Hernández (Partido de La Plata), both belonging to the province of Buenos Aires. Several specimens of A. mollis were collected on april 2015, and those that presented an egg or a small larva attached to the back of the abdomen were selected. They were kept under observation in a bioterium until completing the development of the wasp's adult state. Of the total spiders collected, 9.6% were parasitized by wasps. Of that percentage, four larvae of E. platensis reached the adult stage (three females and one male). The results obtained contribute to the knowledge of a new interaction between wasps and spiders.

Resumen En el presente estudio se dan a conocer por primera vez, datos sobre la interacción entre ejemplares de avispas de la especie Epipompilus platensis Roig Alsina, 2017 (Hymenoptera, Pompilidae) y arañas de la especie Ariadna mollis (Holmberg 1876) (Araneae, Segestriidae), en las localidades de Punta Lara (partido de Ensenada) y José Hernández (partido de La Plata), ambas pertenecientes a la provincia de Buenos Aires. Se recolectaron varios ejemplares de A. mollis en el mes de abril del 2015, y se seleccionaron aquellos que presentaban un huevo o una pequeña larva adherida al dorso del abdomen. Se mantuvieron bajo observación en bioterio hasta completar el desarrollo al estado adulto de la avispa. Del total de las arañas colectadas, el 9.6% se encontró parasitado por avispas. De ese porcentaje, cuatro larvas de E. platensis llegaron al estado adulto (tres hembras y un macho). Los resultados obtenidos contribuyen al conocimiento de una nueva interacción entre avispas y arañas.

Abstract There are few studies dedicated to the natural history of Neotropical spider wasps (Pompilidae). When it comes to urban areas, the knowledge on these wasps is even scarcer. This study sheds light on the natural history of Auplopus cf. rufipes and A. cf. brasiliensis (Hymenoptera: Pompilidae: Ageniellini) from an urban Atlantic Forest fragment in the Jardim Botânico do Rio de Janeiro, Rio de Janeiro City, Brazil. Auplopus cf. rufipes displays a multivoltine pattern and frequently nests in bamboo canes scattered in the open areas, whereas A. cf. brasiliensis is a rare sight, with only a single nest collected from a hose trap-nest. Females of the former species show aggressive behaviour, which suggests a solitary lifestyle. Their nests were partly enveloped in a complex structure, similar to other species that build free-standing, unconcealed nests and display some degree of sociality. Such behaviour could not be observed for A. cf. brasiliensis. Despite that, nests of both species were built using mud pellets, though the brood cells differed regarding arrangement and position in the trap. Two parasites were found attacking the cells: Caenochrysis crotonis (Chrysididae) in a cell of A. cf. rufipes, and Chaenotetrastichus neotropicalis (Eulophidae) in two cells of A. cf. brasiliensis, both recorded for the first time. Auplopus cf. rufipes was found to prey on Frigga cf. quintensis (Salticidae), the first record of this genus as a host of Auplopus.

ABSTRACT Despite the fact that E. chlorotica (Linnaeus, 1766) is common and widely distributed in South America, the reproductive aspects of the species are poorly documented. Here we present data on 18 active nests found from August to February, between 2007 and 2012. Nests were globular with a lateral entrance, and measured 97.9 ± 14.4 mm in outside height, 110.6 ± 11.6 mm in outside diameter, and were 4.88 ± 2.09 m above ground. They were often supported from bellow and were composed mainly of tiny dry leafs and leaflets, fine petioles, and plumed seeds, all compacted with spider web silk. Eggs were laid on consecutive days or with one day interval, and clutch size varied from 1-3 eggs (2.1 ± 0.6, n = 9 nests). Only females incubated the eggs, but both sexes were involved in nest construction and nestling attendance at similar rates. Incubation and nestling periods were 14 and 21 days, respectively, and overall nest survival probability was 5%. A vespiary used for nesting was not occupied by wasps and nest material was deposited only to form the incubatory chamber. Although nesting near wasps or bees is a widespread strategy among birds in general, nesting inside the nests of social insects is a poorly documented behavior.

Despite precautions, the spontaneous invasion of undesired arthropod pests in greenhouses seems to be unavoidable. Secondary plants can be employed in biological control to enhance the proliferation of desired natural enemies of arthropod pests. However, these additional plants may also attract pests which in turn attack the crop plants. The present study is part of a long-term experiment to test eight species of banker plants (BPs) and their efficiency for biological protection against the spider mite Tetranychus urticae, employing the predatory mite Amblyseius californicus as natural enemy. Our goal was to find the best suited local plant species to be used as BPs, which enhances the reproduction and continuous release of the predators in a greenhouse. In the present paper, we document the spontaneous invasion of arthropods on eight species of BPs in a time span of three months, in a greenhouse in Southern France. The first arthropods appeared spontaneously on some of the plants after 4-8 weeks. After three months, there were 6 additional species of arthropods (whiteflies Trialeurodes vaporariorum, rose aphids Rhodobium porosum, gall midges Feltiella acarisuga, flower thrips Frankliniella occidentalis, parasitic wasps Encarsia sp. and predatory mites Phytoseiulus persimilis). Different species of plants attracted different species of arthropods. None of the pest arthropods reproduced on the available BPs in the experimental phase and thus did not represent a problem for the ornamental crop (rose plants). This shows that the mere presence of arthropods in a greenhouse might not affect the crop, as long as there is certain diversity of plant species. Although BPs may act as involuntary multipliers for pests, our study shows that, under the given conditions, this was not the case for the chosen BPs.

En los cultivos de invernadero, a pesar de las precauciones, a veces es inevitable la instalación espontánea de especies no deseadas de plagas de artrópodos. Para el control biológico, se pueden emplear plantas secundarias que aumenten la proliferación de los enemigos naturales de dichos artrópodos plaga. Sin embargo, estas plantas adicionales también pueden atraer plagas que ataquen a los cultivos. El presente estudio tiene que ver con los datos producto del efecto secundario de un experimento a largo plazo que ponía a prueba ocho especies de plantas banco (PB) y su eficacia para la protección biológica contra el ácaro Tetranychus urticae, empleando al ácaro depredador Amblyseius californicus como enemigo natural. La intención era encontrar las mejores especies de plantas locales adecuadas para ser utilizadas como PB, que mejoren la reproducción y liberación continua de los depredadores en un invernadero. A pesar de todas las precauciones, después de un corto período hubo muchas especies exóticas en las PB en el invernadero. En el presente trabajo se documenta la instalación espontánea de artrópodos en ocho especies de BP en un plazo de tres meses, en un invernadero en el sur de Francia. Después de 4-8 semanas desde el inicio del experimento, los primeros artrópodos aparecieron espontáneamente en algunas de las plantas. Después de tres meses se encontraron 6 especies adicionales de artrópodos (moscas blancas Trialeurodes vaporariorum, áfidos rosa Rhodobium porosum, moscas hiel Feltiella acarisuga, trips Frankliniella occidentalis, avispas parásitas Encarsia sp. y ácaros depredadores Phytoseiulus persimilis). Diferentes especies de plantas atrajeron distintas especies de artrópodos, de acuerdo con las propiedades químicas específicas y los rasgos morfológicos, como hirsutismo foliar, superficies de cera, o la presencia de domatia, típico de algunas especies de plantas. Estas no se reprodujeron en las plantas disponibles en la fase experimental y por lo tanto no representaron un problema para los cultivos. Esto muestra que la presencia de los artrópodos en un invernadero no afecta seriamente el cultivo, siempre que hay una cierta diversidad de especies de plantas presentes. Es posible que las plantas banco actúen como multiplicadores involuntarios para las plagas, pero para las especies aquí elegidas, no hay evidencia de que esto suceda. Nuestro estudio muestra que las plantas banco elegido, en las condiciones dadas, no contribuyeron a una multiplicación de los artrópodos plagas.

Se estudió el género Psorthaspis en Colombia. Se encontraron tres especies distribuidas en el norte y occidente de Colombia, de ellas dos representan nuevos registros de Pompilidae en el país: Psorthaspis variegata y Psorthaspis connexa que se encuentran en Chocó y Magdalena, respectivamente. Se establece un neotipo para Psorthaspis colombiae. La variación morfológica y la distribución de P. variegata y P. connexa hacen necesario evitar el uso de unidades subespecíficas. Se ofrece una discusión del estado de estas subespecies. Se presenta una clave para los miembros de Psorthaspis en Colombia.

The biodiversity of spider wasps in Psorthapsis occurring in Colombia was examined in this study. Three species of this genus were found in northern and western Colombia, of which two represent new distributional records: Psorthaspis variegata and Psorthaspis connexa are recorded from Chocó and Magdalena, respectively. A neotype is established for Psorthapsis colombiae. The morphological variation, coupled with geographic distribution, precludes the division of P. variegata and P. connexa into subspecies. A discussion on the status of these subspecies is provided. A key to the members of the genus in Colombia also is presented.

En este trabajo se estudia la biología de la nidificación de cuatro especies de Trypoxylon (Trypargilum) recolectadas a partir de 91 nidos-trampa en el Bosque Chaqueño Serrano de Córdoba, Argentina. La arquitectura de los nidos fue similar para las cuatro especies: celdas de cría ubicadas linealmente, una detrás de la otra separadas por tabiques de barro, como es habitual en otras especies del subgénero Trypargilum. El 48% de los nidos presentó celda vestibular, mientras que sólo dos nidos presentaron celdas intercalares. El ancho de los tabiques y el largo de las celdas de cría difirió entre las especies y estuvo relacionado con el tamaño de las avispas que emergieron. Así mismo, el diámetro del nido-trampa estuvo directamente relacionado con el tamaño corporal promedio de las especies de mayor y menor tamaño. La mortalidad debida a parasitoides (Eulophidae; Melittobia sp.) fue similar para las cuatro especies, mientras que la causada por cleptoparásitos (Chrysididae) fue mayor en T. lactitarse. No fue posible relacionar la presencia de celda vestibular con la mortalidad debida a enemigos naturales para ninguna de las especies. La familia de arañas más frecuentemente utilizada como presa fue Araneidae.

Trypoxylon (Trypargilum) (Crabronidae) wasps are solitary spider predators that can build their nests in artificial trap-nests, which enables study of their nesting architecture and biology. Twenty traps (each containing 15-30 internodes of cane) were placed in each of nine sites of Chaco Serrano Woodland in Central Argentina (Córdoba) in October 2005, and were recovered in June 2006. We obtained 91 nests of four species of Trypoxylon (Trypargilum). In the laboratory, each Trypoxylon nest was sectioned longitudinally to study its architecture. The number of brood cells was counted, and the occurrence and length of vestibular and intercalary cells and the pre-closing plug space were recorded. We measured the diameter of the cane entrance, total length of the nest, length of each brood cell, maximum thickness of mud partitions and closing plug thickness. We also recorded the cell contents: the wasps, their natural enemies and the prey spiders. Mortality was assessed and the sex ratio calculated for each species. Finally, the nests were examined to help clarify the function of the vestibular cell. The nest architecture was similar in the four species, with linear brood cells located one after the other separated by mud partitions, as in other species of the subgenus Trypargilum. Forty-eight percent of the nests had vestibular cells, but only two had intercalary cells. The thickness of the mud partitions and the length of the brood cells differed among species and were related to the size of the emerged wasp. The diameter of the nest entrance was directly related to the average length of the fore-tibia. Sex ratios of all species did not deviate from 0.5. Mortality due to parasitoids (Eulophidae; Melittobia sp.) was similar among species, while the mortality due to cuckoo wasps (Chrysididae) in T. lactitarse was higher than in the other species. The presence of vestibular cells was not related either to the mortality due to natural enemies or to the orientation of the trap in the field. Spiders in the family Araneidae were the most frequently collected prey. Rev. Biol. Trop. 58 (4): 1177-1188. Epub 2010 December 01.

One hundred and two species and thirty two genera of the four subfamilies of Pompilidae wasps, collected at localities of eight municipalities of Tamaulipas, México were recorded. Twenty one species of these are new records for the country meanwhile 88 species are new records for the state of Tamaulipas. The most abundant species were Aporus notabilis notabilis y Episyron conterminus posterus. Thirty three species are Neotropical. The results suggest that others species will be present in this region of the country and therefore more studies must be necesary to make in order to know the richness of this group of wasps.

Se registran 102 especies y 32 géneros de las cuatro subfamilias de avispas Pompilidae, colectadas en localidades de ocho municipios de Tamaulipas, México. De éstas, 21 especies son nuevos registros para el país y 88 especies son nuevos registros para el Estado de Tamaulipas. Las especies más abundantes fueron Aporus notabilis notabilis y Episyron conterminus posterus. Entre las especies, 33 son de afinidad neotropical. Es muy posible que más especies estén presentes en esta región del país y por lo tanto será necesario realizar más estudios encaminados a conocer la riqueza de este grupo de avispas.

Vespas do gênero Trypoxylon apresentam comportamento solitário e aprovisionam seus ninhos de forma massiva com aranhas paralisadas. Algumas espécies utilizam cavidades preexistentes para nidificação, o que facilita sua amostragem e estudo. Neste trabalho, dados sobre a biologia de nidificação de quatro espécies de Trypoxylon (Trypargilum) - T. rogenhoferi, T. lactitarse, T. aurifrons e T. nitidum - são apresentados. As espécies foram amostradas por meio de ninhos-armadilha durante três anos em Araras e dois anos em Rifaina e São Carlos (São Paulo). As localidades de estudo foram subdivididas em sítios de amostragem. Foram obtidos 2.698 ninhos de himenópteros solitários, dos quais 2.268 foram fundados por espécies de Trypoxylon. Intensa atividade de nidificação foi observada principalmente na estação quente e chuvosa (outubro-março). Os ninhos-armadilha utilizados para nidificação pelas diferentes espécies apresentaram dimensões significativamente diferentes. A família de aranhas mais utilizada para aprovisionamento foi Araneidae; no entanto, as espécies de vespas diferiram quanto às espécies forrageadas. O principal parasitóide das quatro espécies foi Melittobia, mas indivíduos das famílias Chrysididae, Ichneumonidae, Chalcididae e Sarcophagidae também foram verificados. Observou-se que as espécies de Trypoxylon coexistem temporalmente e que nas três localidades cada espécie nidificou com maior freqüência em um sítio particular, sugerindo uma ocupação diferencial do habitat. A partição do habitat aparentemente homogêneo pode ser resultado de "competição aparente" mediada por inimigos naturais comuns.

Wasps of the genus Trypoxylon are solitary and females mass-provision their nests with paralyzed spiders. Some species use successfully trap-nests for nesting foundation, making easier their sampling and study. This paper reports data about nesting biology of four species of Trypoxylon (Trypargilum) - T. rogenhoferi, T. lactitarse, T. aurifrons and T. nitidum. These species were sampled by trap-nests during three years in Araras and two years in São Carlos and Rifaina (São Paulo). These areas were subdivided into sampling sites. A total of 2,698 nests of solitary hymenopterans were collected and most of them (2,268) were founded by Trypoxylon species. Nesting activity was higher in the warm, rainy season (October-March). The trap-nests used by the different species showed significantly different dimensions. Araneidae was the spider family mainly used for provision, but a species-specific provisioning was observed. The most important parasitoid of the four species was Melittobia, but adult chrysidids, ichneumonids, chalcidids and sarcophagids also attacked their nests. In the three areas, the different species of Trypoxylon coexist temporally but each of them built their nests frequently in a specific site. This result may suggest differential occupation of the habitat. This habitat partition of an apparently homogeneous area may be a result of an "apparent competition" shaped by shared natural enemies.

Las tasas de parasitismo de Theridion evexum por la avispa parasitoide Zatypota petronae y de Allocyclosa bifurca por Polysphincta gutfreundi fueron estudiadas durante dos años. El parasitismo en T. evexum fue muy bajo (promedio 1.39+1.8%) y restringido a aproximadamente siete meses del año. El parasitismo en A. bifurca fue más alto (promedio 7.8+7.6%) y no mostró un claro patrón estacional. La reproducción de la araña hospedera T. evexum fue muy estacional, con solamente una generación por año, mientras que los adultos de A. bifurca estuvieron presentes todo el año. Autocorrelaciones de las tasas de parasitismo entre censos consecutivos en diferentes sitios sugiere que P. gutfreundi tiende a retornar a los mismos sitios para parasitar las arañas hospederas durante algunas semanas.

The rates of parasitism of Theridion evexum by the parasitoid wasp Zatypota petronae, and Allocyclosa bifurca by Polysphincta gutfreundi, were followed for two years. Parasitism of T. evexum was very low (mean 1.39+1.8%), and restricted to nearly seven months of the year. Parasitism of A. bifurca was higher (mean 7.8+7.6%), and did not show a seasonal pattern. Reproduction of the host spider T. evexum was highly seasonal, with only one, highly coordinated generation per year, while adults of A. bifurca were present year round. Short-term autocorrelation on parasitism rates over time at different sites suggest that P. gutfreundi tend to return to the same sites to hunt hosts over periods of a few weeks. Rev. Biol. Trop. 56 (2): 749-754. Epub 2008 June 30.

Fifty five nests and 216 cells of Trypoxylon (Trypargilum) rogenhoferi were obtained from trap-nests (cut bamboo canes) in Santa Carlota Farm (Itaoca Section=IS and Santana Section=SS), Cajuru and on the São Paulo University Campus, Ribeirão Preto (=RP), both in the State of São Paulo, Brazil (Sept. 1993 - Oct. 1995). The prey (spiders) of 40 cells from IS, 58 from SS and 39 from RP were identified. The greatest nesting frequency occurred during the hot and wet season (September to April). T. rogenhoferi preyed upon individuals of five spider families, with Araneidae (orb-weaver spiders) being the most frequent (99.6%). Alpaida aff. negro (58%) was the most frequently collected species in IS, followed by A. alto (24.8%); in SS (59.6%) and RP (64.7%) the most frequent species was A. veniliae, followed in SS by A. aff. negro (14.9%) and in RP by A. leucogramma (13.5%). The size of reproductive niches, H’=1.25 (IS), H’=1.30 (SS) and H’=1.29 (RP) were not significantly different. There was a positive correlation between the reproductive niche width (H’) and evenness.

Fifty one nests and 200 cells of Trypoxylon (Trypargilum) lactitarse were obtained from trap-nests (cut bamboo stems) in Santa Carlota Farm (in two habitats: Itaoca Section-IS and Santana Section-SS), Cajuru and on the São Paulo University Campus, Ribeirão Preto (RP), both in the State of São Paulo, Brazil. The prey (spiders) of 18 cells from IS, 38 from SS and 70 from RP were identified. Nesting most frequently occurred during the hot and wet seasons (September to April). T. lactitarse preyed upon representatives of ten spider families. Araneidae (96.6%) (orb-weaver spiders) were the most frequent. Eustala sp.1 was the most frequently collected species in the three habitats (31.6% in IS, 20.1% in SS and 48.7% in RP), followed by Acacesia hamata (19.5%) and Alpaida leucogramma (10%) in IS, by Parawixiaaudax (16%) and A. hamata (15.4%) in SS and by P.audax (17.9%) and Eustala sp.2 (12%) in RP. The sizes of the reproductive niches were significantly different. There was a positive correlation between reproductive niche width and evenness.

Ninhos de Trypoxylon (Trypargilum) lactitarse Saussure e Trypoxylon (Trypargilum) rogenhoferi Kohl foram obtidos em ninhos-armadilhas na Fazenda Santa Carlota, Cajuru, SP e Campus da Universidade de São Paulo, Ribeirão Preto, SP. Os ninhos de T. lactitarse (n=51) e de T. rogenhoferi (n=55) foram construídos em gomos de bambu que variaram em comprimento e diâmetro interno, respectivamente, de 88,2 a 233,9 mm e de 7,4 a 14,7 mm, para a primeira espécie e de 104,1 a 201,2 mm e de 7,5 a 14,8 mm para a segunda. As células foram aprovisionadas com aranhas, previamente paralisadas, em número variável de três a 23 aranhas e as biomassas de 129,1 a 367,9 mg, para T. lactitarse, e de três a 24 aranhas e de 143,8 a 506,6 mg, para T. rogenhoferi. Células de T. lactitarse contendo de três a 11 e de T. rogenhoferi de três a 12 presas apresentaram biomassas semelhantes às daquelas contendo de 12 a 23 e de 13 a 24, respectivamente. Para as duas espécies estudadas, os machos mostraram-se menores que as fêmeas, enquanto que machos e fêmeas de T. rogenhoferi foram maiores do que aqueles de T. lactitarse. A família de aranha mais representada nas coletas foi Araneidae, a qual correspondeu a 96,6% dos indivíduos capturados por T. lactitarse e 99,45% daqueles capturados por T. rogenhoferi; as espécies de aranhas mais coletadas pelo primeiro e segundo predador foram Eustala sp1 (37,6%) e Alpaida veniliae (Keyserling) (48,1%), respectivamente.

Nests of Trypoxylon (Trypargilum) lactitarse Saussure and Trypoxylon (Trypargilum) rogenhoferi Kohl were obtained from trap-nests at Fazenda Santa Carlota, Cajuru, SP and at the Campus of the Universidade de São Paulo, Ribeirão Preto, SP. Nests of T. lactitarse (n=51) and T. rogenhoferi (n=55) were constructed in bamboo canes, 88.2 to 233.9 mm in length and 7.4 to 14.7 mm in internal diameter for the first species and 104.1 to 201.2 mm in length and 7.5 to 14.8 mm in internal diameter for the second one. Individual brood cells of T. lactitarse were provisioned with three to 23 paralyzed spiders and the total weight varied from 129.1 to 367.9 mg, whereas T. rogenhoferi were provisioned with three to 24 spiders and their weight varied from 143.8 to 506.6 mg. Cells of T. lactitarse with three to 11 and of T. rogenhoferi with three to 12 spiders showed weight similar to those with 12 to 23 and 13 to 24 spiders, respectively. For both species, females were larger than males, and males and females of T. rogenhoferi were larger than those of T. lactitarse. Araneidae was the most abundant family of spiders, with 96.6% of captures for T. lactitarse and 99.4% for T. rogenhoferi; the spider preys most collected by the first and second predator species were Eustala sp.1 (37.6%) and Alpaida veniliae (Keyserling) (48.1%), respectively.