DOI: 10.3897/neotropical.18.e103506

Authors: Gabriela Morais Olmedo, Mateus Raguse-Quadros, Guilherme Taboada Conrado, Juliano Morales Oliveira

Abstract: The study of vegetative and reproductive phenophases of plants is critical for understanding aspects related to plant behavior in different environments. In the tropics, there is a gap of understanding related to plant phenology since the theoretical framework on the topic has been built from perspectives of the temperate region. Furthermore, there are few studies in tropical regions influenced by anthropic conditions, which may be important for understanding these issues in the face of future climate scenarios. This study aimed to describe the vegetative and reproductive phenology of trees in an urban subtropical forest community and to test the influence of climatic variables on the tree community. In an urban forest fragment in Rio Grande do Sul, Brazil, eight individuals of locally dominant species were monitored: Allophylus edulis, Casearia sylvestris, Guarea macrophylla, Mimosa bimucronata, Myrsine coriacea, Myrsine umbellata, Schinus glandulosum, and Schinus terebinthifolia. The monitoring occurred every two weeks, for two years, with the recording of the presence of leaf flushing, leaf shedding, flowering, and fruiting phenophases for each tree. The seasonality of the species was tested using the Rayleigh test. We described the common pattern of community phenological activity by a Principal Component Analysis. Finally, we correlated the common patterns of each phenophase in the community with climatic variables of total precipitation, average temperature, and day length. All species showed a non-uniform phenological pattern for the evaluated phenophases despite the variable intensity. We evidenced common patterns for the community only for the vegetative phenophases. The reproductive phenophases of flowering and fruiting present themselves independently among species in the community. Finally, we identified influences only of temperature and day length on the vegetative phenophases.

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DOI: 10.3897/neotropical.16.e58188

Authors: Manuela Gazzoni dos Passos, Geisa Percio do Prado, Claudia Fontana, Edilvane Ines Zonta, Edmilson Bianchini

Abstract: The study of forest regeneration allows the diagnosis of conservation status of fragments and estimating population parameters that are essential for management projects. This study evaluated the structure, diversity and dynamics of the tree regenerating component of a remnant of mixed ombrophilous forest, aiming to support management actions for this forest type. The study was developed at the Parque Estadual das Araucárias (PEAR), located in the western region of the state of Santa Catarina, southern Brazil. A total of 100 plots of 25 m2 (0.25 ha) were allocated, all individuals with height ≥ 1.0 m and DBH < 5 cm were sampled. Shannon’s diversity index (H’), Pielou’s equability index (J) and total natural regeneration rate (TNR) were estimated. We sampled 1,425 individuals from 99 species and 39 families, with an estimated total density of 5,700 individuals by hectare. The richest families were Fabaceae (13), Myrtaceae (10) and Lauraceae (7). The H’ was 3.76 and the J was 0.80. The TNR rate ranged from 0.05 to 8.12%, highlighting Trichilia elegans, with the highest rate and Araucaria angustifolia with low potential for natural regeneration. The analysis of the results indicated a high diversity in the regenerating component of the PEAR compared to other studies, probably because the area presents itself as a successional mosaic due to past disturbances.

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DOI: 10.3897/neotropical.16.e56427

Authors: Juliano Ricardo Fabricante, Kelianne Carolina Targino de Araújo, Thieres Santos Almeida, João Paulo Bispo Santos, Daniel Oliveira Reis

Abstract: Biological invasions are considered one of the greatest threats to global biodiversity. In addition, they cause substantial economic impacts. However, studies about the subject in Brazil are still scarce. The aim of the present study was to prepare an inventory of non-native flora with invasive potential from Sergipe, Brazil. The inventory was carried out along the entire length of the sites. The species with potential invaders were grouped according to the biome/ecosystem and classified according to their habit and origin. Eighty-five species with invasive potential were sampled, 43 in the Caatinga, 75 in the Atlantic Forest, 36 in Sandbank and 22 in Mangrove. From these species, 17 were inventoried in all the biomes/ecosystems and 36 were observed in only one of them, six in the Caatinga, 27 in the Atlantic Forest and three in Sandbank. The number of potentially-invasive species sampled in Sergipe is alarming. The present study showed nearly twice the species listed by other authors for the entire northeast Brazil. This high number of taxa may be a consequence of facilitating the transfer of these species and the conservation conditions of the ecosystems studied in Sergipe. Another very worrying factor is that many of the species sampled are extremely aggressive and cause a series of impacts.

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DOI: 10.3897/neotropical.15.e54142

Authors: Felipe Fajardo Villela Antolin Barberena, Deivid Lucas de Lima da Costa, José Antônio Lima Rocha Junior

Abstract: The re-discovery of Catasetum mojuense A.T. Oliveira & J.B.F. Silva (Orchidaceae), an Amazonian species described in 1999 from the State of Pará, Brazil, is reported. In addition to geographic distribution data, a morphological description, taxonomical and ecological comments, conservation status assessment and photographs of C. mojuense are also provided. The species is characterised by having epiphytic habit, non-resupinate staminate flowers, brown-spotted petals, galeiform and smooth (no ribs) lip, lateral lobes with sparsely short-fimbriate margins and convergent antennae. Catasetum mojuense is morphologically similar to Catasetum discolor (Lindl.) Lindl, but is easily distinguished by the longer sepals and petals and the spotted petals on the staminate flowers. The new locality of occurence for C. mojuense is approximately 190 km east of the type locality, also in the State of Pará. The species is assessed as Critically Endangered. Habitat depletion and the limited number of sites of occurrence are the main concern for the conservation of C. mojuense.

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DOI: 10.3897/neotropical.15.e54017

Authors: Ana Y. Y. Meiga, Alexander V. Christianini

Abstract: Defaunation, the decline in animal species and populations, is biased towards large-bodied animals that have unique roles as dispersers of large seeds. However, it is speculated that these roles may still be performed by smaller animals, such as small mammals like rodents and marsupials, that thrive in defaunated sites. We investigated if small mammals can disperse the large-seeded palm Attalea dubia. We performed the study in a well-conserved Atlantic Forest remnant in southeast Brazil that still harbours large mammals, such as tapirs. Focal observations showed that capuchin-monkeys consumed the mesocarp of the fruits and dropped the seeds beneath the plant crown thereafter. Mammals preyed on ca. 1% and removed ca. 15% of the fallen fruit/seed and deposited them up to 15 m away. Amongst them, small mammals (< 1 kg), such as the squirrel Guerlinguetus brasiliensis and non-identified nocturnal Sigmodontinae, as well as the marsupial Philander frenatus performed the bulk of interactions. Dispersal enhances recruitment, but the short distances of seed removal did not match the current spatial distribution of palm seedlings and juveniles. Recaching rates of hoarded seeds were small (2%) and unlikely to increase distances of seed dispersal achieved. Short distances of dispersal would increase plant clumpiness and negative density-dependent effects with time. Although small mammals can provide legitimate dispersal, they cannot fully replace larger frugivorous mammals and maintain long-distance seed dispersal that feeds plant metapopulation dynamics and seed gene flow.

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DOI: 10.3897/neotropical.15.e49114

Authors: José Paulo Santana, Patrício Adriano da Rocha, Eduardo Vinícius da Silva Oliveira, Ana Paula Nascimento Prata, Adauto Souza Ribeiro

Abstract: Among the various applications of phytosociology, the evaluation of natural regeneration is of great importance, mainly because it provides insights for ecological restoration. The objective of this study was to analyze the composition and phytosociological parameters of shrub and tree vegetation in areas of plantation of eucalyptus (Corymbia citriodora) and areas of native forest in the Ibura National Forest, located in the Sergipe state of northeastern Brazil. For this purpose, 20 plots were sampled and all individuals with a diameter at breast height (DBH) ≥ 8 cm were measured. Sampling revealed 821 individuals in the forest area and 1,000 in the eucalyptus area. These individuals represent 84 species and the areas presented a significant difference in species composition, with 61 in the eucalyptus area and 65 in the Forest area, and only 40 species were common to both areas. There was a predominance of pioneer individuals in the eucalyptus area. There also was a significant difference in basal area, relative density and relative dominance, but no significant differences were observed in average height. It was concluded that a period of 35 years is insufficient for the recovery of the eucalyptus area, which remains in a more initial successional stage than the forest area.

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DOI: 10.3897/neotropical.15.e49013

Authors: Annette Aiello, Brian J. Stucky

Abstract: Twenty-nine Pacarina (Hemiptera: Cicadidae) adults, 12 males and 17 females, emerged from the soil of a potted Dracaena trifasciata (Asparagaceae) in Arraiján, Republic of Panama, providing the first rearing records and the first definitive host plant records for any species of Pacarina. These reared Pacarina appear to be morphologically distinct from all known species of Pacarina and likely represent an undescribed species. In light of this finding, we also discuss the taxonomy, biogeography, and ecology of Pacarina.

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