Enchytraeids are small oligochaetes found worldwide in soils with sufficient moisture and organic matter, but scarcely studied in the Southern hemisphere. This is the third study on enchytraeid abundance in Brazil using wet extraction and the first carried out in Araucaria Mixed Forest (subtropical region). The sampling and extraction were based on the standard method ISO 23611-3/2007 using an adapted split soil corer and wet extraction with and without heat to assess the abundance of enchytraeids in a forest fragment at Embrapa Forestry in Colombo, Paraná State. The samplings were performed in 3 occasions between September 2011 and April 2012. The average numbers estimated by each method varied from appr. 2.000-12.000 (cold) and 5.000-12.000 ind./ m 2 (hot), respectively, with a maximum of 44.000 ind./ m 2 in one of the samples, the highest value reported so far in Brazil. The hot extraction was more advantageous, given the speed and preservation of the specimens in vivo, allowing taxonomic identification. Advantages and disadvantages of wet extractions compared to handsorting and formol methods are also discussed. Guaranidrilus, Hemienchytraeus, Enchytraeus, Fridericia and Achaeta were the genera identified in the samples.Keywords: Enchytraeidae, Oligochaeta, extraction methods, Araucaria, subtropical. Abundância de enquitreídeos na Floresta Ombrófila Mista determinada por extração úmida quente e fria ResumoOs enquitreídeos são pequenos oligoquetas encontrados no mundo todo em solos com suficiente umidade e matéria orgânica, porém muito pouco estudados no hemisfério Sul. Este é o terceiro estudo sobre a abundância de enquitreídeos no Brasil utilizando o método de extração úmida e o primeiro realizado em Floresta Ombrófila Mista (região subtropical).A amostragem e extração foram baseadas no método padrão ISO 23611-3/2007, utilizando-se um trado desmontável adaptado e extração úmida com e sem aquecimento para acessar a abundância de enquitreídeo em um fragmento de floresta na Embrapa Florestas em Colombo, Paraná. As amostragens foram realizadas em três ocasiões entre setembro, 2011 e abril 2012. Os números médios estimados através de cada método variaram de 2.000-12.000 (frio) e 5.000-12.000 ind./ m 2 (quente), respectivamente, e o máximo de 44.000 ind./ m 2 em uma das amostras, o mais alto já relatado no Brasil. A extração quente foi a mais vantajosa, considerando a rapidez e preservação dos exemplares in vivo. As vantagens e desvantagens das extrações úmidas comparadas aos métodos de triagem manual e extração com formol foram discutidas. Os gêneros Guaranidrilus, Hemienchytraeus, Enchytraeus, Fridericia e Achaeta foram identificados nas amostras.Palaras-chave: Enchytraeidae, Oligochaeta, métodos de extração, Araucária, subtropical.

Over 150 species of earthworms are known from the Brazilian Atlantic rainforest, but many more are expected to live in this megadiverse biome. In the present study, we evaluated earthworm species occurrence and diversity in native and reforested areas in four National Forests in three Brazilian states: Três Barras National Forest (Santa Catarina), Irati and Piraí do Sul National Forests (Paraná) and Capão Bonito National Forest (São Paulo) using formalin and hand sorting methods. A total of 13 species were found, five exotic and eight natives (of which four were new, undescribed species), belonging to six genera and five families (Rhinodrilidae, Glossoscolecidae, Ocnerodrilidae, Benhamiidae, Megascolecidae). In general, higher number of earthworms were collected in Araucaria plantations, except in Capão Bonito where Pinus sp. plantations had higher abundance. Hand sorting also collected more species in all forests, so this should be the preferred sampling method to evaluate earthworm communities. Formalin extraction was efficient only for epi-endogeic earthworms, most of them exotic species. Exotic pine species plantations tend to reduce species richness and abundance, compared with native forests and Araucaria plantations, and substitution of native vegetation for pine plantations should consider potential negative effects on soil animal populations.

The diets of 3 of the most abundant coastal pelagic fish species in the eastern Atlantic (sardine, anchovy and Atlantic chub mackerel) were investigated, including seasonal, geographical and ontogenetic variability of the diets. We also estimated the impact of cannibalism and intraguild predation on egg mortality, and a different method to evaluate egg mortality is proposed taking the spatial overlap of predators and eggs into account. Diet overlap occurred between the 3 pelagic species, which derive most of their dietary carbon from mesozooplankton prey. However, calanoid copepods were mostly important for anchovy and sardine, whereas the diet of the Atlantic chub mackerel also included crustacean eggs, nauplii, small copepodites and larger prey such as decapods. Sardine was the main predator of fish eggs (90% of all identified eggs), followed by Atlantic chub mackerel (8%) and anchovy (2%). Cannibalism by anchovies and sardines on their eggs was low (<10% of spawned eggs) for all areas and seasons. The impact of sardine predation on anchovy egg mortality was high (71% of the anchovy eggs spawned per day during the spring off northwestern Iberia) and may explain why anchovy abundance has only peaked in recent years, when sardine abundance was at its lowest level, highlighting the importance of taking an ecosystem approach to fisheries management into account. However, species-specific data of gastric evacuation rates and feeding durations are needed to obtain more accurate estimates of the impact of cannibalism and intraguild predation on egg mortality.

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