From species descriptions to diversity patterns: the validation of taxonomic data as a keystone for ant diversity studies reproducibility and accuracy.

Research findings in natural sciences need to be comparable and reproducible to effectively improve our understanding of ecological and behavioural patterns. In this sense, knowledge frontiers in biodiversity studies are directly tied to taxonomic research, especially in species-rich tropical regions. Here we analysed the taxonomic information available in 470 studies on Brazilian ant diversity published in the last 50 years. We aimed to quantify the proportion of studies that provide enough data to validate taxonomic identification, explore the frequency of studies that properly acknowledge their taxonomic background, and investigate the primary resources for ant identification in Brazil. We found that most studies on Brazilian ant diversity (73.6%) explicitly stated the methods used to identify their specimens. However, the proportion of papers that provide complete data for the repository institutions and vouchered specimens is vanishingly small (5.8%). Additionally, only 40.0% of the studies consistently presented taxon authorities and years of description, rarely referencing taxonomic publications correctly. In turn, the number of specialists and institutions consulted for ant identification in Brazil has increased in the last years, along with the number of studies that explicitly provide their taxonomic procedures for ant identification. Our findings highlight a shift between generations regarding the recognition of taxonomy as fundamental science, deepening our understanding of biodiversity.

Testing the context dependence of ant nutrient preference across habitat strata and trophic levels in Neotropical biomes.

Animals are integrated into the wider ecosystem via their foraging and behavior. The compensation hypothesis predicts that animals target their foraging efforts (i) toward nutrients that are scarce in the environment and (ii) toward nutrients that are not present in the usual diet of species, which varies across trophic levels. Understanding how foraging for resources varies locally, such as across habitat strata, and trophic levels will help to elucidate the links between the local environment and communities to the ecological functions that animals mediate. We examined whether the relative resource use of ants varies consistently along a habitat strata gradient and across trophic levels across Neotropical biomes. We placed 4500 baited tubes, each containing one of five liquid resources (sugar, amino acid, lipid, sodium, and distilled water) in one of three habitat strata (subterranean, epigaeic, and arboreal) across 60 transects in Amazon, Atlantic Forest, Caatinga, Cerrado, Pampa, and Pantanal biomes. We assessed the relative resource use of all ants across the habitat strata and among two different trophic groups across biomes. The relative preference for sugar increased from subterranean to arboreal strata in all biomes, while the relative preference for lipids decreased at this gradient in five biomes. We also found that in general sugar-consuming ants foraged more for sugar and less for lipids than predatory ants across biomes. Conversely, we found no consistency across biomes in nutrient preference of amino acid and sodium across habitat strata or trophic levels. Overall, our results indicate sugar limitation in the arboreal stratum and lipid limitation on the ground across biomes and that the trophic level of ants strongly determines their foraging efforts-possibly because ants try to fix their dietary nutrient imbalances. Hence, our findings suggest strong local niche partitioning of sugar and lipid use across habitat strata and trophic levels and that other large spatial scale processes influence the local amino acid and sodium dynamics.

Os animais se integram nos ecossistemas pelos seus esforços e comportamento de forrageio. A hipótese da compensação prevê que os animais direcionam seus esforços de forrageio para (i) nutrientes que são escassos no ambiente e (ii) para nutrientes que não estão presentes em sua dieta, que variam entre os níveis tróficos. Assim, entender como a busca de recursos varia localmente entre os estratos de habitat e entre níveis tróficos, ajudará a entender as conexões entre o ambiente e suas comunidades com as funções ecológicas mediadas pelos animais. Avaliamos se o uso relativo de recursos das formigas varia consistentemente em um gradiente de estratos de habitat e em diferentes níveis tróficos nos biomas Neotropicais. Disponibilizamos um total de 4.500 tubos contendo um de cinco recursos líquidos (açúcar, aminoácido, lipídio, sódio e água destilada) em três estratos de habitat (subterrâneo, epigéico e arbóreo) em 60 transectos distribuídos nos biomas Amazônia, Mata Atlântica, Caatinga, Cerrado, Pampa e Pantanal. Avaliamos o uso relativo de recursos de todas as formigas ao longo dos estratos de habitat e entre dois grupos tróficos diferentes nos biomas. A preferência relativa por açúcar aumentou do estrato subterrâneo para o arbóreo em todos os biomas, enquanto a preferência relativa por lipídios diminuiu neste gradiente em cinco biomas. Também descobrimos que, em geral, as formigas consumidoras de açúcar procuram mais açúcar e menos lipídios do que as formigas predadoras nos biomas. Por outro lado, não encontramos consistência entre biomas na preferência nutricional de aminoácidos e sódio nos estratos de habitat ou níveis tróficos. No geral, nossos resultados indicam limitação de açúcar no estrato arbóreo e limitação de lipídios no solo em todos os biomas e que o nível trófico das formigas determina fortemente seus esforços de forrageamento - possivelmente porque as formigas tentam corrigir seus desequilíbrios de nutrientes na dieta. Portanto, nossas descobertas sugerem forte partição de nicho local de uso de açúcar e lipídios em estratos de habitat e níveis tróficos e que outros processos de grande escala espacial influenciam a dinâmica local de aminoácidos e sódio.

Temperature and productivity distinctly affect the species richness of ectothermic and endothermic multitrophic guilds along a tropical elevational gradient.

The diversity of endotherms and ectotherms may be differently affected by ambient temperature and net primary productivity (NPP). Additionally, little is known about how these drivers affect the diversity of guilds of different trophic levels. We assessed the relative role of temperature and NPP in multitrophic guilds of ectothermic (arthropods: ants, ground beetles, spiders, and harvestmen) and endothermic (large mammals) animals along a tropical elevational gradient. We sampled arthropods at eight elevation belts and large mammals at 14 elevation belts in Atlantic rainforest (ranging from 600 to 2450 m.a.s.l.) of Itatiaia National Park, Southeast Brazil. Overall arthropod species richness was more associated with temperature than overall large-mammal species richness, while the latter was more associated with NPP. When separated into trophic guilds, we found that the species richness associated with NPP increased across arthropod trophic levels from herbivores to predators. Conversely, although NPP influenced large-mammal herbivore species richness, its effects did not seem to accumulate across large-mammal trophic levels since the species richness of large-mammal omnivores was more associated with temperature and none of the variables we studied influenced large-mammal predators. We suggest that thermal physiological differences between ectotherms and endotherms are responsible for the way in which arthropods and large mammals interact with or are constrained by the environment. Furthermore, the inconsistency regarding the role of temperature and NPP on species richness across multitrophic guilds of ectotherms and endotherms could indicate that thermal physiological differences might also interfere with energy use and flux in the food web.

Head and mandible shapes are highly integrated yet represent two distinct modules within and among worker subcastes of the ant genus Pheidole.

Ants use their mandibles for a wide variety of tasks related to substrate manipulation, brood transport, food processing, and colony defense. Due to constraints involved in colony upkeep, ants evolved a remarkable diversity of mandibular forms, often related to specific roles such as specialized hunting and seed milling. Considering these varied functional demands, we focused on understanding how the mandible and head shape vary within and between Pheidole subcastes. Using x-ray microtomography and 3D geometric morphometrics, we tested whether these structures are integrated and modular, and how ecological predictors influenced these features. Our results showed that mandible and head shape of majors and minor workers tend to vary from robust to slender, with some more complex changes related to the mandibular base. Additionally, we found that head and mandible shapes are characterized by a high degree of integration, but with little correlation with feeding and nesting habits. Our results suggest that a combination of structural (allometric) constraints and the behavioral flexibility conferred by subcaste dimorphism might largely buffer selective pressures that would otherwise lead to a fine-tuning between ecological conditions and morphological adaptation.

A "Dirty" Footprint: Macroinvertebrate diversity in Amazonian Anthropic Soils.

Amazonian rainforests, once thought to be pristine wilderness, are increasingly known to have been widely inhabited, modified, and managed prior to European arrival, by human populations with diverse cultural backgrounds. Amazonian Dark Earths (ADEs) are fertile soils found throughout the Amazon Basin, created by pre-Columbian societies with sedentary habits. Much is known about the chemistry of these soils, yet their zoology has been neglected. Hence, we characterized soil fertility, macroinvertebrate communities, and their activity at nine archeological sites in three Amazonian regions in ADEs and adjacent reference soils under native forest (young and old) and agricultural systems. We found 673 morphospecies and, despite similar richness in ADEs (385 spp.) and reference soils (399 spp.), we identified a tenacious pre-Columbian footprint, with 49% of morphospecies found exclusively in ADEs. Termite and total macroinvertebrate abundance were higher in reference soils, while soil fertility and macroinvertebrate activity were higher in the ADEs, and associated with larger earthworm quantities and biomass. We show that ADE habitats have a unique pool of species, but that modern land use of ADEs decreases their populations, diversity, and contributions to soil functioning. These findings support the idea that humans created and sustained high-fertility ecosystems that persist today, altering biodiversity patterns in Amazonia.

Temperature and productivity distinctly affect the species richness of ectothermic and endothermic multitrophic guilds along a tropical elevational gradient

The diversity of endotherms and ectotherms may be differently affected by ambient temperature and net primary productivity (NPP). Additionally, little is known about how these drivers affect the diversity of guilds of different trophic levels. We assessed the relative role of temperature and NPP in multitrophic guilds of ectothermic (arthropods: ants, ground beetles, spiders, and harvestmen) and endothermic (large mammals) animals along a tropical elevational gradient. We sampled arthropods at eight elevation belts and large mammals at 14 elevation belts in Atlantic rainforest (ranging from 600 to 2450 m.a.s.l.) of Itatiaia National Park, Southeast Brazil. Overall arthropod species richness was more associated with temperature than overall large-mammal species richness, while the latter was more associated with NPP. When separated into trophic guilds, we found that the species richness associated with NPP increased across arthropod trophic levels from herbivores to predators. Conversely, although NPP influenced large-mammal herbivore species richness, its effects did not seem to accumulate across large-mammal trophic levels since the species richness of large-mammal omnivores was more associated with temperature and none of the variables we studied influenced large-mammal predators. We suggest that thermal physiological differences between ectotherms and endotherms are responsible for the way in which arthropods and large mammals interact with or are constrained by the environment. Furthermore, the inconsistency regarding the role of temperature and NPP on species richness across multitrophic guilds of ectotherms and endotherms could indicate that thermal physiological differences might also interfere with energy use and flux in the food web.

Taxonomic revision of the genus Prionopelta Mayr, 1866 (Formicidae: Amblyoponinae) for the Neotropical region.

The ant genus Prionopelta Mayr, 1866 is revised for the Neotropics. Morphological traits combined with geographical data led to the recognition of eight species, four of them described here as new: Prionopelta dubia sp. n., Prionopelta menininha sp. n., Prionopelta minuta sp. n., and Prionopelta tapatia sp. n. Prionopelta marthae Forel, 1909 is proposed as a new junior synonym of Prionopelta antillana Forel, 1909. External morphological descriptions of the worker caste for all species are provided, as well as for some of the males and queens, mostly described here for the first time. Identification keys for all known castes, distribution maps and high-resolution illustrations are supplied for all species.

Additions to the taxonomy of Gnamptogenys Roger (Hymenoptera: Formicidae: Ectatomminae) with an updated key to the New World species.

This study aimed to raise and address nomenclatural issues surrounding Neotropical species in the genus Gnamptogenys, in addition to describing new species accumulated in myrmecological collections. New and reinstated names recognized here include G. pernambucana (Santschi) sp. rev., stat.n., G. lenis sp. n., G. latistriata sp. n., and G. avus sp. n. The queen and intercaste of G. lavra Lattke and the queen of G. pernambucana are described for the first time. For these five species we provide complete descriptions and diagnoses, comments on taxonomy and natural history, distribution data, and high-resolution images, including the first images of G. lavra. An updated identification key for all the Neotropical species of Gnamptogenys is also provided, including the new and revived species as well as G. aspera Morgan and G. pilosa Lattke, not present in previous keys for the genus.

First checklist of the ants (Hymenoptera: Formicidae) of French Guiana.

We provide here a checklist of the ants of French Guiana, an overseas department of France situated in northern South America, with a very low human population density and predominantly covered by old-growth tropical rainforests. Based on 165 scientific papers, specimens deposited in collections, and unpublished surveys, a total of 659 valid species and subspecies from 84 genera and 12 subfamilies is presented. Although far from complete, these numbers represent approximately 10% of the ant diversity known to occur in the Neotropical realm. Additionally, three ant genera and 119 species are reported for the first time for French Guiana. Finally, five species are recognized as erroneous records for the the department in the literature. This checklist significantly expands the basic knowledge of the ants in the Guiana Shield, one of the world's most important biodiversity hotspots.

Taxonomic revision of the genus Probolomyrmex Mayr, 1901 (Hymenoptera: Formicidae: Proceratiinae) for the Neotropical Region.

We revise the taxonomy of the ant genus Probolomyrmex for the Neotropical region. Eight species are recognized, four of them already known: P. boliviensis, P. brujitae, P. guanacastensis, and P. petiolatus. Four new species are described: P. cegua sp. n., P. dentinodis sp. n., P. kelleri sp. n. and P. lamellatus sp. n. We present complete descriptions and redescriptions for all the species, including diagnoses, comments on the taxonomic history and biology, high-quality images, and scanning electron microscope micrographs for diagnostic anatomic structures. In addition, distribution maps and an illustrated identification key are provided.

A new species of Pheidole (Formicidae, Myrmicinae) from Dominican amber with a review of the fossil records for the genus.

Pheidole comprises approximately 1,000 extant species distributed worldwide, being particularly diverse in the New World. In addition to its high diversity and ecological prevalence, the genus is also characterized by the predominantly intraspecific dimorphism, with major and minor workers. Currently, five fossil species are known, all of which are represented only by minor workers. A new species, †Pheidoleanticua sp. nov., is described from Dominican amber, based on a major worker. Additionally, the identity of the currently known fossil species in Pheidole is discussed and †P.cordata from Baltic amber is considered as incertae sedis, resulting in no Pheidole species currently recognized for Baltic amber.

Using controlled vocabularies in anatomical terminology: A case study with Strumigenys (Hymenoptera: Formicidae).

Morphological studies of insects can help us to understand the concomitant or sequential functionality of complex structures and may be used to hypothetize distinct levels of phylogenetic relationship among groups. Traditional morphological works, generally, have encompassed a set of elements, including descriptions of structures and their respective conditions, literature references and images, all combined in a single document. Fast forward to the digital era, it is now possible to release this information simultaneously but also independently as data sets linked to the original publication in an external environment. In order to link data from various fields of knowledge, disseminating morphological information in an open environment, it is important to use tools that enhance interoperability. For example, semantic annotations facilitate the dissemination and retrieval of phenotypic data in digital environments. The integration of semantic (i.e. web-based) components with anatomic treatments can be used to generate a traditional description in natural language along with a set of semantic annotations. The ant genus Strumigenys currently comprises about 840 described species distributed worldwide. In the Neotropical region, almost 200 species are currently known, but it is possible that much of the species' diversity there remains unexplored and undescribed. The morphological diversity in the genus is high, reflecting an extreme generic reclassification that occurred in the late 20th and early 21st centuries. Here we define the anatomical concepts in this highly diverse group of ants using semantic annotations to enrich the anatomical ontologies available online, focussing on the definition of terms through subjacent conceptualization.

Ant fauna associated with Microgramma squamulosa (Kaulf.) de la Sota (Polypodiaceae) fern galls

Abstract Galls are neoformed plant structures created by cell hyperplasia and hypertrophy induced by a number of organisms, especially insects. After adult insects hatch, senescent galls may remain on the host plant and be occupied by a succession of fauna, the most important and dominant being ants. This study aimed at characterizing the ant fauna successor of stem galls induced by microlepidoptera in Microgramma squamulosa (Kaulf.) de la Sota (Polypodiaceae). Four collections were carried out in the municipality of Nova Friburgo, Rio de Janeiro state, Brazil. The galls were packed in plastic bags and taken to the laboratory. Ants were euthanized and conserved in 70° GL alcohol and later identified. A total of 49 stem galls were collected and analyzed, 15 containing microlepidoptera galler larvae, one a parasitoid wasp and 33 without the microlepidoptera or parasitoid (67%). Twelve of these galls (39%) contained ants. Six ant species were recorded (Camponotus crassus, Crematogaster curvispinosa, Crematogaster sericea, Procryptocerus sampaioi, Tapinoma atriceps, and Wasmannia auropunctata), all native to Brazil. Ant occupation in M. squamulosa seems to be associated with senescent galls due to hatching of the galler insect, which leaves a hole that allows ants to colonize it, in other words, an opportunistic domatia. Senescent galls resulting from the death of galler insects do not seem to facilitate ant occupation.

Diurnal flight periodicity of a Neotropical ant assemblage (Hymenoptera, Formicidae) in the Atlantic Forest

ABSTRACT In this study we document for the first time flight patterns along a 24 h time range for an ant assemblage in one of the most diverse ecosystems on Earth, the Brazilian Atlantic Forest. Malaise traps were used to analyze the diurnal nuptial flights of a Neotropical ant assemblage during five days. Traps captured 802 individuals, revealing a remarkably high diversity (42 ant species), with samples strongly male biased (1:22). Contrariwise to similar studies, we found only a small proportion of species engaged in nocturnal nuptial flights, with diurnal flights accounting for an impressive 95% of all ant flight activity recorded. For the 18 most common species, three ant groups could be identified regarding flight period: sunrise, sunset, and continuous flight activity. Similarity analyses, however, suggest that closely related time ranges of flight activity may actually not be continuous. Further, three species showed pulsed flight activity, at varied hours of the day. Two species of Hypoponera showed flight activity at different periods of the day, suggesting congeneric staggered nuptial flights. Our results match long-term studies of ant assemblages showing high diversity of flight phenologies in hyperdiverse tropical ant assemblages and provide the first data on the reproductive phenology for several Neotropical ant species.

Timeless standards for species delimitation.

Recently a new species of bombyliid fly, Marleyimyia xylocopae, was described by Marshall & Evenhuis (2015) based on two photographs taken during fieldwork in the Republic of South Africa. This species has no preserved holotype. The paper generated some buzz, especially among dipterists, because in most cases photographs taken in the field provide insufficient information for properly diagnosing and documenting species of Diptera.

Bird and ant synergy increases the seed dispersal effectiveness of an ornithochoric shrub.

Seed dispersal may involve different vectors of dispersal in two or more sequential phases (i.e., diplochory). However, contributions of each phase to the overall seed dispersal effectiveness (SDE) are poorly understood and hard to evaluate due to post-dispersal processes that affect seed and seedling survival. We investigated the simultaneous bird (phase 1, in plant canopy) and ant (phase 2, on the floor) contributions to SDE with the ornithochoric shrub Erythroxylum ambiguum in a Brazilian Atlantic forest. Twelve species of birds fed on fruit and dispersed approximately 26 % of the seed crop. The remaining seed crop, 90 % of which contained viable seeds, fell to the ground beneath the parental plant. Ants either cleaned seeds in fruits or carried fallen fruit and seeds from bird feces to their nests. Although E. ambiguum has no adaptation for ant dispersal, ants were as quantitatively important as birds. Birds and ants equally increased germination rates compared to controls. However, birds deposited seeds farther from the parent, where seedling survival was higher (78 %) than it was beneath the parent (44 %), whereas ants carried seeds to their nests, where seedling survival was higher (83 %) than in controls away from their nests (63 %). Diplochory allowed a 42 % increase in SDE compared to dispersal in phase 1 alone. High lipid content in the fruit pulp of E. ambiguum may facilitate the inclusion of ants in a second step of dispersal after diaspores reach the floor. Ants can also buffer the dispersal of diplochorous plants against decreases in phase 1 dispersers.

Taxonomic revision of the Neotropical Myrmicinae ant genus Blepharidatta Wheeler.

We revise the taxonomy of the exclusively Neotropical Myrmicinae ant genus Blepharidatta (Attini), redescribing the known species (B. brasiliensis and B. conops), and describing two new species, B. delabiei sp. n. (Brazil: Bahia) and B. fernandezi sp. n. (Colombia: Amazonas). We also describe worker sting apparatuses, larvae, males, and ergatoid gynes of all species, except for B. fernandezi, known only from few worker specimens; we provide a key for identifying workers, present distribution maps for all species and summarize the knowledge on the biology of Blepharidatta species.