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After much debate, there is an emerging consensus that the composition of many ecological communities is determined both by species traits, as proposed by niche theory, as well as by chance events. A critical question for ecology is, therefore, which attributes of species predict the dominance of deterministic or stochastic processes. We outline two hypotheses by which organism size could determine which processes structure ecological communities, and we test these hypotheses by comparing the community structure in bromeliad phytotelmata of three groups of organisms (bacteria, zooplankton, and macroinvertebrates) that encompass a 10 000-fold gradient in body size, but live in the same habitat. Bacteria had no habitat associations, as would be expected from trait-neutral stochastic processes, but still showed exclusion among species pairs, as would be expected from niche-based processes. Macroinvertebrates had strong habitat and species associations, indicating niche-based processes. Zooplankton, with body size between bacteria and macroinvertebrates, showed intermediate habitat associations. We concluded that a key niche process, habitat filtering, strengthened with organism size, possibly because larger organisms are both less plastic in their fundamental niches and more able to be selective in dispersal. These results suggest that the relative importance of deterministic and stochastic processes may be predictable from organism size.

Three new state-level records for the genus Agarista are reported in Brazil. The distribution of Agarista revoluta is expanded in Northeast Brazil, with new occurrences in Alagoas and Pernambuco. Agarista eucalyptoides is newly recorded for Espírito Santo, based on previously misidentified collections, raising to three the number of Agarista species known in the state. These two species are the most widely distributed in Brazil, with A. eucalyptoides also occurring in Uruguay. Descriptions, distribution maps, and an updated taxonomic key for Espírito Santo are provided as a supplement to the previously published flora. Additionally, all taxa were assessed according to their conservation status.

The genus Polistomorpha (Hymenoptera: Leucospidae) is exclusive to the Neotropical region, comprising seven species. Polistomorpha fasciata has previously been recorded in the Brazilian states of Amapá, Amazonas, Pará, and São Paulo. This study presents the first record of P. fasciata from Northeast Brazil, parasitizing Euglossa cordata within a Restinga ecosystem. Additionally, it provides an extended diagnosis and illustrations of P. fasciata, E. cordata, and its nest. El género Polistomorpha (Hymenoptera: Leucospidae) es exclusivo de la región neotropical, con siete especies, seis de ellas en Brasil. Polistomorpha fasciata se registró anteriormente en Amapá, Amazonas, São Paulo y Pará. Este estudio proporciona el primer registro de P. fasciata en el Noreste de Brasil, parasitando a Euglossa cordata en un ecosistema de Restinga. También incluye un diagnóstico ampliado e ilustraciones de P. fasciata, E. cordata y su nido.

Aim: We aimed to assess the contribution of marginal habitats to the tree species richness of the Mata Atlântica (Atlantic Forest) biodiversity hotspot In addition, we aimed to determine which environmental factors drive the occurrence and distribution of these marginal habitats. Location: The whole extension of the South American Atlantic Forest Domain plus forest intrusions into the neighbouring Cerrado and Pampa Domains, which comprises rain forests (\"core\" habitat) and five marginal habitats, namely high elevation forests, rock outcrop dwarf-forests, riverine forests, semideciduous forests and restinga (coastal white-sand woodlands). Methods: We compiled a dataset containing 366,875 occurrence records of 4,431 tree species from 1,753 site-checklists, which were a priori classified into 10 main vegetation types. We then performed ordination analyses of the species-by-site matrix to assess the floristic consistency of this classification. In order to assess the relative contribution of environmental predictors to the community turnover, we produced models using 26 climate and substrate-related variables as environmental predictors. Results: Ordination diagrams supported the floristic segregation of vegetation types, with those considered as marginal habitats placed at the extremes of ordination axes. These marginal habitats are associated with the harshest extremes of five limiting factors: temperature seasonality (high elevation and subtropical riverine forests), flammability (rock outcrop dwarf-forests), high salinity (restinga), water deficit severity (semideciduous forests) and waterlogged soils (tropical riverine forests). Importantly, 45% of all species endemic to the Atlantic Domain only occur in marginal habitats. Main conclusions: Our results showed the key role of the poorly protected marginal habitats in contributing to the high species richness of the Atlantic Domain. Various types of environmental harshness operate as environmental filters determining the distribution of the Atlantic Domain habitats. Our findings also stressed the importance of fire, a previously neglected environmental factor.

ABSTRACT Biological invasions pose significant threats to native biodiversity, particularly within coastal ecosystems. During long-term monitoring of populations of the threatened lizard Liolaemus lutzae Mertens, 1938 along the coast of Rio de Janeiro State, Brazil, we documented the widespread establishment of the non-native lizard Salvator merianae Duméril & Bibron, 1839 in the beach habitat of Barra da Tijuca, located within the environmental protection area (APA da Orla Marítima) in the municipality of Rio de Janeiro. In October 2024, we recorded 18 individuals of S. merianae, although this number is likely underestimated due to the species’ burrowing behavior. The presence of S. merianae within this protected area represents a potential risk to the persistence of L. lutzae through competition for space and resources or predation. Continuous monitoring, the implementation of a targeted removal program, and the urgent restoration of native dune habitats are recommended to mitigate the impact of this invasion and safeguard local biodiversity.

The flora of the Guiana Shield contains several plant lineages that are restricted to white‐sand vegetation, some of which are widespread in tropical South America. Here, the history of diversification of one of these lineages, the genus Pagamea (Rubiaceae), is reconstructed through phylogenetic hypotheses. Data from chloroplast (rps16 and rpl20‐rps12) and nuclear (ITS) markers were incongruent, with ITS found to be more consistent with morphological criteria to delimit species. Reconstruction of the ancestral area for the genus was ambiguous, with both the western Guiana Shield and the Atlantic coastal areas containing early divergent lineages, but most speciation events appeared to have happened in the western Guiana Shield where most extant diversity is present. Dispersal events into the western Amazon and the Andes (1.5–4.5 Ma) and the eastern Guiana Shield (0.4–2.2 Ma) were followed by speciation events in these regions. Dispersal events between the Amazon and Atlantic rain forest occurred at least three times independently. However, dispersals into new areas were limited, and most regions were found to be phylogenetically clustered. Altitudinal and habitat shifts happened multiple times independently, but ecological traits were found to be phylogenetically conserved, implying that such shifts were not the cause of lineage divergence. The result that most speciation events happened in the western Guiana Shield, where white‐sand habitats predominate in both lowlands and highlands, and which has been less affected by Pleistocene climatic change, coupled with the result that ecological traits are phylogenetically conserved, suggests that the diversification of Pagamea may have been related primarily to the patchy distribution of white‐sand vegetation.

ABSTRACT Experiments with artificial nests are widely used to gain insights into the behavioral and ecological factors affecting the survival of natural nests. Undesired effects on nest success may arise from variations in nest and egg characteristics (e.g., dimensions, texture, and color). Still, evaluating these potential factors is seldom considered in the design of artificial nest studies, particularly in tropical regions. We assessed the effect of two nest types (cup-shaped and dome-shaped) and two egg types (differing in size and color) on the survival of artificial nests. The egg types included smaller (22-25 mm), variously colored eggs of blue-breasted quails, Synoicus chinensis (Linnaeus, 1766) and larger (25-30 mm), white-spotted-with-brown eggs of Japanese quails, Coturnix japonica Temminck & Schlegel, 1848. The experiment took place within a coastal shrubland (restinga) in southeastern Brazil, from August 16-31, 2017. This period coincides with the onset of the breeding season for most insectivorous bird species in the region. The nests were observed for 15 days to assess predation, revealing higher survival rates in dome-shaped nests than cup-shaped ones. Egg type, however, did not affect survival rates. This suggests that coastal shrubland nest survival is influenced by factors seen in other Neotropical environments, where dome-shaped nests are likewise less vulnerable to predation. Interestingly, egg color and size did not impact nest predation in this environment. We suggest that future studies on artificial nests should incorporate variations in nest types and validate the selection of egg types.

Spatial limitation in seed arrival is pervasive among species in tropical forests and has been considered an important mechanism for species coexistence. Temporal limitation, when associated to a non-synchronous within-year pattern of seed arrival, could also contribute to species coexistence by diminishing encounter chances among species with distinct competitive abilities. However, temporal seed limitation (TSL) at the community level has been scarcely measured. Data from monitoring seed traps each month for three years in a subtropical Atlantic coastal plain forest in southeastern Brazil were used to evaluate if TSL could be an important mechanism structuring the community and if it was associated with an asynchronous pattern of temporal seed distribution. Furthermore, it was investigated if the values of spatial seed limitation (SSL) and TSL for each species were correlated and if some species traits could be used as a proxy for their SSL or TSL patterns. The SSL and TSL values were very high and strongly positively correlated, with 75% of the species found in less than four seed traps or three months each year. Within-year temporal seed distribution was clearly non-synchronous, but when compared to null models, there was no evidence of a deterministic process of temporal partitioning among species. Species with heavy seeds showed stronger SSL and TSL than species with light seeds. Our results suggest that high TSL associated with a non-synchronous temporal distribution could act as a complementary mechanism that structures this community by reducing encounter chances among species.

The lichen family Parmeliaceae is among the best studied groups of lichens. Canoparmelia amazonica, Myelochroa lindmanii, and Parmelinella salacinifera are species of Parmeliaceae that have yet to be studied in detail with molecular methods. This study used analyses of ITS sequences to examine the phylogenetic position of these three species. Canoparmelia amazonica and M. lindmanii were recovered within Parmelinella rather than the genera to which they are currently assigned. While for the P. salacinifera we confirmed its phylogenetic position within the genus. Chemical and morphological descriptions of species are provided, generic placement is discussed, and new combinations are proposed as needed. These results highlight the need for morphological revision of the delimitation of Parmelinella, a small genus of Parmeliaceae that has been considered well-defined morphologically and is phylogenetically closely related to Bulbothrix s.l.

Environmental features are predictors that assist in identifying patterns of species richness. To obtain accurate richness estimates, occupancy modeling is a useful tool because it can encompass variables at multi-scales and considers imperfect detection. We estimated the relative bird richness in a protected area in the Atlantic Forest to understand habitat requirements of a species assemblage as a function of environmental factors. Our study spanned dry and rainy seasons and covered four habitats (seasonal semideciduous forest, restinga, a planted experimental forest, and patch edge) across 42 sampling sites. Using point counts, we recorded all bird species during three visits at each site. We estimated species richness across temporal and spatial scales using community occupancy modeling. We recorded 86 species where four were threatened: the Pectoral Antwren (Herpsilochmus pectoralis), the White-collared Kite (Leptodon forbesi), the Rusty-margined Guan (Penelope superciliaris), and the Long-tailed Woodnymph (Thalurania watertonii). Relative species richness in the rainy season (Ψ = 0.31–0.66) was lower compared to the dry season (Ψ = 0.37–0.76). Open habitats had a higher richness (Ψ of patch edge = 0.66 and 0.76, Ψ of restinga = 0.51 and 0.62) than seasonal semideciduous forest (Ψ = 0.31 and 0.37) and planted experimental forest (Ψ = 0.36 and 0.40). Rates of species gain varied among habitats (γ = 0.15–0.59), unlike species loss, which did not vary (ε = 0.15). Richness at each site was negatively affected by pond distance, tree cover, and diameter of tree trunks. The low richness observed in seasonal semideciduous forest is probably a reflection of negative impacts on the area, such as the effects of forest fragmentation. We also highlight that occupancy modeling results in reliable estimates for ecological inferences, aiding in understanding patterns that can be evaluated and used in habitats and community conservation strategies. As características ambientais são preditores que ajudam a identificar padrões de riqueza de espécies. Para obter estimativas precisas de riqueza, a modelagem de ocupação é uma ferramenta útil porque pode abranger variáveis em múltiplas escalas e considera a detecção imperfeita. Estimamos a riqueza relativa de aves em uma área protegida na Mata Atlântica para compreender as exigências de habitat da assembleia de espécies em função de fatores ambientais. Nosso estudo abrangeu as estações seca e chuvosa e cobriu quatro habitats (floresta estacional semidecidual, restinga, floresta experimental plantada e borda da mancha) em 42 sítios de amostragem. Usando contagem de pontos, registramos todas as espécies de aves durante três censos em cada sítio. Estimamos a riqueza de espécies em escalas temporais e espaciais usando modelagem de ocupação para comunidades. Registramos 86 espécies, onde quatro estão ameaçadas de extinção: o chorozinho-de-papo-preto (Herpsilochmus pectoralis), o gavião-gato-do-nordeste (Leptodon forbesi), a jacupemba (Penelope superciliaris) e o beija-flor-de-costasvioleta (Thalurania watertonii). A riqueza relativa de espécies na estação chuvosa (Ψ = 0,31–0,66) foi menor em comparação com a estação seca (Ψ = 0,37–0,76). Os habitats abertos apresentaram maior riqueza (Ψ da borda da mancha = 0,66 e 0,76, Ψ da restinga = 0,51 e 0,62) do que a floresta estacional semidecidual (Ψ = 0,31 e 0,37) e a floresta experimental plantada (Ψ = 0,36 e 0,40). As taxas de ganho de espécies variaram entre habitats (γ = 0,15–0,59), ao contrário da perda de espécies, que não variou (ε = 0,15). A riqueza em cada sítio foi afetada negativamente pela distância das lagoas, cobertura de árvores e diâmetro dos troncos de árvores. A baixa riqueza observada na floresta estacional semidecidual é provavelmente um reflexo dos impactos negativos sobre a área, tais como os efeitos da fragmentação florestal. Também destacamos que a modelagem de ocupação resulta em estimativas confiáveis para inferências ecológicas, auxiliando na compreensão de padrões que podem ser avaliados e usados em habitats e estratégias de conservação de comunidades. ; ; ; ; ; ;