Ant diversity (Hymenoptera: Formicidae) in Turvo State Park, municipality of Derrubadas, state of Rio Grande do Sul, Brazil

The knowledge of ant assemblages that occurs in Conservation Units in the Atlantic Forest domain is a priority, considering the number of endemic species and the impacts that this biome has been suffering. The aim of this study was to evaluate ant assemblages in the Turvo State Park, which is the largest conservation unit in the State of Rio Grande do Sul and presents an important role on biodiversity protection. Two samplings were conducted in 2019, one in the summer (January) and the other in the spring (November and December), at five sites 2 km apart, with pitfall traps (soil and canopy), sardine baits, glucose, beating net, sweeping net and manual collection. We sampled 121 species in the summer and 120 in the spring, totaling 163 ant species. A total of 78 species (47.8%) occurred in both sampling seasons. The richest genera in the study were Camponotus (S = 30), Pheidole (S = 23) and Linepithema (S = 11). Seventeen species were recorded for the first time for Rio Grande do Sul state. The results indicate that this is one of the most species-rich assemblages of ants ever surveyed in a conservation unit in southern Brazil. The study highlights the importance of Conservation Units as protected environments against habitat loss for ant biodiversity. The results of this study contribute to myrmecofauna knowledge and serve as a basis for environmental impact studies, management plans and conservation of Atlantic Forest remnants.

Unrecognized Ant Megadiversity in Monsoonal Australia: Diversity and Its Distribution in the Hyperdiverse Monomorium nigrius Forel Group

We document diversity and its distribution within the hyperdiverse Monomorium nigrius Forel group of the Australian monsoonal tropics, an unrecognized global centre of ant diversity. The group includes a single described species, but several distinct morphotypes each with multiple clearly recognizable taxa are known. Our analysis is based on 401 CO1-sequenced specimens collected from throughout the Australian mainland but primarily in the monsoonal north and particularly from four bioregions: the Top End (northern third) of the Northern Territory (NT), the Sturt Plateau region of central NT, the Kimberley region of far northern Western Australia, and far North Queensland. Clade structure in the CO1 tree is highly congruent with the general morphotypes, although most morphotypes occur in multiple clades and are therefore shown as polyphyletic. We recognize 97 species among our sequenced specimens, and this is generally consistent (if not somewhat conservative) with PTP analyses of CO1 clustering. Species turnover is extremely high both within and among bioregions in monsoonal Australia, and the monsoonal fauna is highly distinct from that in southern Australia. We estimate that the M. nigrius group contains well over 200 species in monsoonal Australia, and 300 species overall. Our study provides further evidence that monsoonal Australia should be recognized as a global centre of ant diversity.

Diversity of ants (Hymenoptera: Formicidae) in the University of Kerala Campus, Thiruvananthapuram, India

Survey conducted on the ant diversity in the Kerala University Campus revealed a total 64 species under six subfamilies. Species belonging to the Myrmicinae dominated (51.5%) followed by Formicinae (20.6%), Ponerinae (13.2%), Dolichoderinae (4.4%), Pseudomyrmicinae (4.4%) and Dorylinae (1.5%). Endemic species Camponotus invidus Forel, 1892 , Cardiocondyla parvinoda Forel, 1902, Carebara spinata Bharti & Kumar, 2013 and Tetramorium rossi (Bolton, 1976) were recorded in the campus. Anoplolepis gracilipes (Smith, 1857), Paratrechina longicornis (Latreille, 1802), Monomorium carbonarium Smith 1858, Solenopsis geminate (Fabricius, 1804), Strumigenys membranifera Emery, 1869, Tetramorium bicarinatum (Nylander, 1846) and Hypoponera ragusai (Emery, 1894) (introduced species) were found in the campus. The results showed that the campus is rich in ant diversity. The sites with human interference showed less diversity. A potential new species in the genus Lepisiota was recorded. Trichomyrmex abberans, Carebara spinata, Crematogaster anthracina, Crematogaster biroi and Nylanderia indica are new records.

Woody Encroachment Affects Multiple Dimensions of Ant Diversity in a Neotropical Savanna

Although savanna woody encroachment has become a global phenomenon, few studies have simultaneously evaluated its effects on multiple dimensions and levels of savanna biodiversity. We evaluated how the progressive increase in tree cover in a fire-suppressed savanna landscape affects the taxonomic, functional, and phylogenetic diversity of neotropical ant communities. We sampled ants along an extensive tree cover gradient, ranging from open savannas to forests established in former savanna areas due to fire suppression, and found that Leaf Area Index explained much of the observed variation in ant diversity at both the alpha and beta levels. However, ant responses to variation in tree cover were largely non-linear as differences in alpha diversity and in the dissimilarities of the sampled communities were often much more marked at the savanna/forest transition than at any other part of the gradient. The patterns of functional and phylogenetic diversity mirrored those of taxonomic diversity, notably at the beta level. At the alpha level, functional diversity tended to increase, whereas taxonomic and phylogenetic diversity decreased or was unrelated to tree cover. Our results indicate that savanna ant communities switch rapidly to an alternative state once savanna turns into forest. Ant communities in the newly formed forest areas lacked many of the species typical of the open habitats, suggesting that the maintenance of a fire suppression policy, is likely to result in a decrease in ant diversity and in the homogenization of the ant fauna at the landscape level.

Small-scale drivers on plant and ant diversity in a grassland habitat through a multifaceted approach

Semi-natural grasslands are characterized by high biodiversity and require multifaceted approaches to monitor their biodiversity. Moreover, grasslands comprise a multitude of microhabitats, making the scale of investigation of fundamental importance. Despite their wide distribution, grasslands are highly threatened and are considered of high conservation priority by Directive no. 92/43/EEC. Here, we investigate the effects of small-scale ecological differences between two ecosites present within the EU habitat of Community Interest of semi-natural dry grasslands on calcareous substrates (6210 according to Dir. 92/43/EEC) occurring on a Mediterranean mountain. We measured taxonomic and functional diversity of plant and ant communities, evaluating the differences among the two ecosites, how these differences are influenced by the environment and whether vegetation affects composition of the ant community. Our results show that taxonomic and functional diversity of plant and ant communities are influenced by the environment. While vegetation has no effect on ant communities, we found plant and ant community composition differed across the two ecosites, filtering ant and plant species according to their functional traits, even at a small spatial scale. Our findings imply that small-scale monitoring is needed to effectively conserve priority habitats, especially for those that comprise multiple microhabitats.

Ant diversity and abundance in pasture system and two agricultural land uses in the Rashad district, Southern Sudan

The most common ecological consequence of biodiversity loss is a reduction in ecosystem functions. These responses, however, vary depending on the type of land-use change and the ecological setting. This study investigated the impact of land-use type and ecosystem functions on the ant assemblage of Rashad district, Sudan. Therefore, the purposes of this study are to evaluate the composition and structure of the ant assembly in the station, as well as to determine the trophic guilds and functional groups and their spatial variation in three different land uses. Furthermore, based on the type of land use to determine how the conversion of native vegetation affects the richness and composition of ant species. In each location, we sampled three 20-meter-long transects (Sample plot). Each sample plot consisted of a grid of 12 pitfall traps arranged in three rows of four traps each, with a 2 m spacing between them, replicated six times in a single year. We collected 38 ant species from four subfamilies and 17 genera. Parasyscia lamborni was the most abundant species followed by Bothroponera crassa. Ant diversity was higher in Soy monoculture and Organic farming than in the Pasture. The frequency distributions of ant Functional groups in Soy monoculture and Organic farming were significantly different from the frequency distributions in the pasture. The omnivorous and predator’s trophic guilds were the best represented and regarding functional groups. We found a high proportion of tropical climate specialists and Myrmicinae generalists. These findings suggest that Pasture Activation reduces ant diversity. It can also help to increase the population of species with a diverse diet that predominate in areas where stress and disturbance prevent other ants from reproducing.

Tree Preference and Temporal Activity Patterns for a Native Ant Community in an Urbanized California Woodland

Anthropogenic disturbances, including land use change and exotic species, can alter the diversity and dynamics of ant communities. To examine foraging behavior in an urbanized habitat in northern California, we surveyed the presence of 9 ant species on 876 trees across 4 seasons during both day and night in a 9.5-hectare urbanized oak-exotic woodland. Ants were more likely to be observed on native, evergreen trees, suggesting that native evergreen species may help maintain ant diversity. Species showed clear patterns of temporal partitioning of foraging activity. Ant species varied in their use of native evergreen Quercus agrifolia trees across season and day/night axes. Of the 3 ant species most frequently observed, Camponotus semitestaceus was most active during spring and summer nights, Formica moki was most active during spring and summer days, and Prenolepis imparis was most active during both day and night during fall and winter. Liometopum occidentale was the second most active species during summer day and night, and winter day. Our findings demonstrate that an oak-exotic urban woodland in Northern California was able to maintain a native ant community, and strong temporal partitioning within that community.

Ant diversity sampling in the Brazilian Amazon: a comparison of litter collection and pitfall trapping

Introduction: Ants in tropical forests are a hyper-diverse group that plays important ecological roles. Several studies on tropical forests have used different sampling protocols to capture soil ants, making it difficult to compare responses and patterns of diversity between studies. Thus, research that compares different well-structured and standardized sampling methodologies to adequately estimate the richness of ant species in tropical forests is necessary. Objective: In this study, we examined the combination of catches with pitfall traps with and without baits and litter collections for soil ant sampling. Methods: In the fall traps, we use two baited (sardines and bananas) and one non-baited. For the manual collections (litter sampling), the litter and only the topsoil of the loose soil were collected. Results: We found that traps containing sardine baits collected a greater abundance of ants, whereas non-baited traps collected a greater richness of ant species. On the other hand, litter collections captured the largest number of exclusive species, presenting a different species composition from the pitfall traps (with and without baits). In general, baited traps showed greater abundance in more degraded locations, while manual collections and unbaited pitfalls captured more individuals in preserved environments. Conclusions: Our results provide evidence that, for accurate sampling of soil ant assemblages in tropical forests, the use of different methodologies is necessary to capture a greater diversity of species because the methods differ in effectiveness according to habitat.