Herbivory and leaf expansion of Cyathea phalerata Mart. (Cyatheaceae) in subtropical Atlantic Forest, southern Brazil

Herbivory is an interaction with great impact on plant communities since relationships between herbivores and plants are fundamental to the distribution and abundance of species over time and space. The aim of this study was to monitor the rate of leaf expansion in the tree fern Cyathea phalerata and evaluate the damage caused by herbivores to leaves of different ages and whether such damage is related to temperature and precipitation. The study was performed in a subtropical Atlantic Forest fragment located in the municipality of Caraá, in the northeast hillside of Rio Grande do Sul state, in southern Brazil. We monitored 24 mature individuals of C. phalerata with croziers in a population of approximately 50 plants. Leaf expansion rate, percentage of damaged leaves and leaf blade consumption rate by herbivory were calculated. Monthly means for temperature and accumulated rainfall were calculated from daily data. Croziers of C. phalerata were found to expand rapidly during the first and second months after emergence (3.98 cm day-1; 2.91 cm day-1, respectively). Damage caused by herbivory was observed in all of the monitored leaves, but none of the plants experienced complete defoliation. The highest percentage (57%) of damaged leaves was recorded at 60 days of monitoring, and also the highest monthly consumption rate of the blade (6.04%) occurred with young, newly-expanded leaves, while this rate remained between 1.50 and 2.21% for mature leaves. Rates of monthly leaf consumption and damaged leaves showed positive and strong relationship with each other and with temperature. The rapid leaf expansion observed for C. phalerata can be considered a phenological strategy to reduce damage to young leaves by shortening the developmental period and accelerating the increase of defenses in mature leaves.

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.

Natural parasitism in fruit fly (Diptera: Tephritidae) and interaction with wild hosts surrounding apple orchards adjacent to Atlantic Forest fragments in Paraná State, Brazil

The South American fruit fly, Anastrepha fraterculus (Wiedemann, 1830) (Diptera: Tephritidae), is an important pest in the subtropical region of Brazil. This insect has tritrophic relation between wild fruits and parasitoids and is associated with apple (Malus domestica Borkh.) orchards adjacent to the Atlantic Forest in Paraná. We thus investigated the degree of infestation of the fruit fly and natural parasitism in wild and cultivated fruits surrounding apple orchards. For this purpose, we collected fruits of Acca sellowiana (Berg.) Burret, Campomanesia xanthocarpa (Mart), Eugenia uniflora L., Eugenia pyriformis Cambessèdes, Psidium cattleianum Sabine, Psidium guajava (L.), Annona neosericea Rainer and Eriobotrya japonica (Thumb) in apple orchards adjacent to the Atlantic Forest located in Campo do Tenente, Lapa and Porto Amazonas counties. In total, we collected 18,289 fruits during four growing years. The occurrence of A. fraterculus depends on the susceptible period of apple fruits. A. sellowiana and P. cattleianum were considered primary fruit fly multipliers and P. guajava was secondary, all occurring after the apple harvest (IS period). The group of parasitoids with A. fraterculus was Aganaspis pelleranoi (Brèthes, 1924) (Hymenoptera: Figitidae), Opius bellus (Gahan, 1930), Doryctobracon areolatus (Szépligeti, 1911) and Doryctobracon brasiliensis (Szépligeti, 1911) (Hymenoptera: Braconidae) all of which are first records in the Atlantic Forest in Paraná. First record of O. bellus occurring in the State of Paraná, as well as, first record of the tritrophic association between host plant A. neosericea, parasitoids D. areolatus and O. bellus and fruit fly A. fraterculus. The host P. cattleianum stood out among the Myrtaceae species in regard to the high diversity of parasitoid species (81% of parasitoids). The total number of Figitidae species (76.5%) was higher than that of Braconidae species. The influence of climatic events in southern Brazil on wild fruit production should be further studied to understand the association of A. fraterculus with the tritrophic relationship.

Dam failure and mammals

Brazil experienced the largest socioenvironmental catastrophe of its history, caused by a tailings dam failure, known as “Mariana disaster”. The wave of iron-mining waste buried villages, contaminated the Doce River, and left an immense ocean plume. The Doce River watershed is the largest in southeast Brazil, and located in the Atlantic Forest domain, presenting an outstanding economic, social, and biological relevance. Although the effects of such tragic events are usually assessed through fish assemblage changes, mammals have important effects on environment structure and regeneration. Inventories are of prime importance for adequate conservation efforts as well as for evaluating impacts of any disaster. Therefore, the aim of this paper was to present an updated assessment of mammalian list collected in the affected portion of Doce River before the dam failure therefore contributing to future conservation efforts. Data collection comprised specimens deposited in Museu Nacional/UFRJ, the oldest mammal collection of Brazil, and literature review. The two surveys together retrieved 157 species from 31 families and 11 orders, representing around 60% of the known mammalian diversity in the Atlantic Forest, including some in critical conservation condition, such as the Franciscana dolphin, the northern muriqui and the giant otter. Mining is a byproduct of present society, with dam breaches as a recurring problem. Facing the importance of Doce River to both Brazilian biodiversity and society, the chain of events must be taken into account in environmental rehabilitation strategies, and taxa less commonly assessed, like mammals, should be included.

The distribution and conservation status of Tapirus terrestris in the South American Atlantic Forest

Tapirus terrestris is the largest South American land mammal, with an extensive historical distribution and capable of occupying diverse habitats, and yet its populations have declined across its range. In order to provide baseline data on the conservation status of tapirs in the Atlantic Forest, we conducted a long-term study in one landscape, visited 93 forests, and received 217 expert reports over the 15-year study. We estimate that 2,665–15,992 tapirs remain in 48 confirmed populations, occupying 26,654 km2 of forest or 1.78% of its original range in the biome. Historically, hunting and deforestation were the main causes of decline, but today population isolation is the principal long-term threat. Vortex models indicate that 31.3–68.8% and 70.8–93.8% of the populations are demographically and genetically non-viable over the next 100 years, respectively, and that only 3–14 populations are viable when considering both variables. Habitat use data indicate that tapirs are adaptable to disturbed and secondary forests and will use diverse tree plantations and agricultural lands but hunting and highways keep populations isolated. Reserve staff report tapirs as common/abundant at 62.2% of the sites, and populations as stable and growing in 60% and 36% of the sites, respectively, and there is ample habitat in the biome for a population expansion, but overcoming the causes of isolation will be necessary for this to occur. Lack of adequate funding for protecting reserves is a chronic threat throughout the biome, especially in federal and state/provincial reserves, and increased funding will be necessary to implement effective conservation plans.

Rediscovery of the rare Phrynomedusa appendiculata (Lutz, 1925) (Anura: Phyllomedusidae) from the Atlantic Forest of southeastern Brazil

The genus Phrynomedusa Miranda-Ribeiro, 1923 comprises rare and little known phyllomedusid species from southern Atlantic Forest, Brazil. Phrynomedusa appendiculata (Lutz, 1925) is known from three localities since its description and considered a “lost species” because it was last sighted 51 years ago. This pervasive lack of knowledge raised a significant concern about its threat status. Here, we present the rediscovery of P. appendiculata from a breeding population in the Atlantic Plateau forests of the state of São Paulo. This new record allowed the gathering of novel ecological, acoustic and morphological data for this species. Most of the novel data agreed with the variation historically reported for the species, but we found subtle divergences that we interpret as intraspecific variation. Moreover, this record also allowed a reassessment of geographic distribution of the species, and the first inference of its phylogenetic relationships based on molecular data (mitochondrial and nuclear DNA). The resulting phylogeny corroborated the generic placement and evolutionary distinctiveness of P. appendiculata, evidencing the species as sister to the clade P. marginata + P. dryade. Based on novel and historical data, we discuss some putative factors influencing the rarity of P. appendiculata and its congeners, and provide conservation perspectives. We expect that the novel data can support further assessments of threat status for this rare species, as well as initiatives aiming its conservation.