Impact of plastic bags on the benthic system of a tropical estuary: An experimental study.

Plastic bags are among the most discarded waste items as they are generally only used once and are often improperly eliminated and transported by rivers and estuaries to the ocean. We developed an experimental design to mimic the effect of plastic bag deposition in a tropical estuary and investigated its short-term impact on benthic community structure. We observed a significant influence of the presence of plastic bags on the abundance, richness and diversity of benthic fauna after an eight-week exposure period. Plastic bags acted as a barrier and interfered in processes that occur at the water-sediment interface, such as organic matter and silt-clay deposition. Our results indicate that plastic bags, in addition to directly affecting benthic fauna, may alter processes such as carbon burying, known as "blue carbon", thus making its storage in the sediment more difficult.

Correction: A synopsis of Salvatoria McIntosh, 1885 (Annelida: Syllidae: Exogoninae) from Brazilian coastal and oceanic waters.

[This corrects the article DOI: 10.1371/journal.pone.0250472.].

A synopsis of Salvatoria McIntosh, 1885 (Annelida: Syllidae: Exogoninae) from Brazilian coastal and oceanic waters.

We compiled the records for the genus Salvatoria from Brazilian coastal and oceanic habitats, collected by several projects along the years. Here we present 12 species, eight of which already reported-S. breviarticulata comb. nov., S. clavata, S. euritmica, S. heterocirra, S. limbata, S. longiarticulata comb. nov., S. neapolitana and S. cf. nitidula-with comments regarding the confidence of some of these records. We also describe three new species, S. marielleae n. sp. and Salvatoria nitiduloides n. sp., based on material from Fernando de Noronha and Trindade islands, off the Northeastern Brazilian coast, and S. ypsiloides n. sp., from Fernando de Noronha and also, Campos Basin, off Southeastern Brazilian coast, in depths down to 970 m. Finally, we report a probably undescribed species, Salvatoria sp., represented by only one specimen lacking median antenna, preventing us to proceed with further identification properly. A dichotomous identification key and a comparative table with morphological data of specimens belonging to these species are also provided.

Diversity and distribution of hidden cultivable fungi associated with marine animals of Antarctica.

In the present study, we surveyed the distribution and diversity of fungal assemblages associated with 10 species of marine animals from Antarctica. The collections yielded 83 taxa from 27 distinct genera, which were identified using molecular biology methods. The most abundant taxa were Cladosporium sp. 1, Debaryomyces hansenii, Glaciozyma martinii, Metschnikowia australis, Pseudogymnoascus destructans, Thelebolus cf. globosus, Pseudogymnoascus pannorum, Tolypocladium tundrense, Metschnikowia australis, and different Penicillium species. The diversity, richness, and dominance of fungal assemblages ranged among the host; however, in general, the fungal community, which was composed of endemic and cold-adapted cosmopolitan taxa distributed across the different sites of Antarctic Peninsula, displayed high diversity, richness, and dominance indices. Our results contribute to knowledge about fungal diversity in the marine environment across the Antarctic Peninsula and their phylogenetic relationships with species that occur in other cold, temperate, and tropical regions of the World. Additionally, despite their extreme habitats, marine Antarctic animals shelter cryptic and complex fungal assemblages represented by endemic and cosmopolitan cold-adapted taxa, which may represent interesting models to study different symbiotic associations between fungi and their animal hosts in the extreme conditions of Antarctica.

The effects of plastic bags presence on a macrobenthic community in a polluted estuary.

The damaging effects of marine debris on wildlife are often noted through the observation of animals that ingest and/or become entangled in debris. Yet, few studies have evaluated the effects of marine litter on benthic habitats. The aim of this study was to investigate if the presence of plastic bags has any effect on benthic macrofauna in an estuary located in an urban area in North-eastern Brazil. Biogeochemical and macrofauna samples were obtained from 10 different deposition locations (location factor), under, border and distant (treatment factor) from plastic bags. The results did not show any significant alterations in the biogeochemical parameters of the sediment due to treatment effect except for summed microphytobenthic pigments. The macrobenthic community structure responded to treatment. The greatest dissimilarity (34%) was between samples that were under and distant. Effects occurred despite the high dynamics of deposition-resuspension of plastic bags and the dominance of opportunistic species. Changes in community structure are a complex result of plastic bags effects on species ecological interactions in the polluted estuarine environment, attracting deposit feeders, diminishing suspension feeders and providing mechanical protection against predation by seabirds.

Two new species and new records of the genus Paraopisthosyllis Hartmann-Schröder, 1991 (Annelida: Syllidae) from northeastern Brazil and Philippine Islands.

Two new species of Paraopisthosyllis are described herein, P. correiae sp. nov. (State of Pernambuco, NE Brazil) and P. kuluguhin sp. nov. (Philippines). Paraopisthosyllis correiae sp. nov. represents the first record for the genus in Brazilian waters and it is also the second species known to occur outside the Pacific Ocean. This species is characterized by having a marked color pattern, with a transverse red stripe between dorsal cirri on each segment and an inverted V anteriorly and a V posteriorly on some segments, small papillae on body, large, distinct papillae on dorsal cirri, compound chaetae with elongated, bidentate blades, shafts with moderate subdistal serration on margin, pharyngeal tooth located on anterior third of pharynx, near the pharyngeal opening, and reproduction by schizogamy. Paraopisthosyllis kuluguhin sp. nov. represents the first report of the genus for the Philippines, together with P. pardus, originally known from Australia and also found in the Philippines in the present study. This new species is characterized by its color pattern, with dark patches irregularly distributed on anterior segments, forming one anterior pigmented short band and two lateral areas on each chaetiger after the proventricle, club-shaped dorsal cirri, and short, bidentate compound chaetae. Our findings allow us to synonymize the genus Basidiosyllis to Paraopisthosyllis and represent the first report of sexual stolons (scissiparity) in this genus, which supports its allocation into the subfamily Syllinae.

On a new species of the rare syllid genus Exogonoides (Annelida, Phyllodocida, Syllidae).

The genus Exogonoides Day, 1963, was described probably based on a single specimen, broken into two pieces (Aguado & San Martín 2008) and no other specimens of the type species, E. antennata Day, 1963, were ever found, which characterizes this species and, until now, the very genus Exogonoides, as 'singletons' (Lim et al. 2012). Although described as a member of the Syllidae Grube, 1850, the positioning of the genus in the family was recently questioned (Aguado & San Martín 2008), since the pharynx of the holotype was dissected for the original description and not preserved with the specimen, resulting that the presence of the proventricle, considered the main synapomorphy of the family, could not be confirmed.

Branchiosyllis, Haplosyllis, Opisthosyllis and Trypanosyllis (Annelida: Syllidae) from Brazil, with the Description of Two New Species.

Brazilian specimens of Branchiosyllis cf. exilis, B. tamandarensis sp. n., Haplosyllis lattigae sp. n., H. loboi, Opisthosyllis brunnea and O. viridis are described and illustrated herein, from recently collected material; also, the distributions of Haplosyllis amphimedonicola and H. rosenalessoae are expanded to other localities in the states of Paraíba and Pernambuco. Branchiosyllis tamandarensis sp. n. was found associated with sponges and is characterized by having a flattened, ribbon-like body, with longitudinal line of mid-dorsal papillae, peristomium dorsally inconspicuous, branchiae with up to six lobes, branchiae and ungulae on all parapodia, and falcigers absent. Haplosyllis lattigae sp. n. is characterized by having two kinds of chaetae with different sizes and shapes per parapodium, papillate dorsum from midbody, and midbody dorsal cirri alternating in length. Additionally, we provide keys to the Brazilian species of Branchiosyllis, Haplosyllis and Opisthosyllis, comparative tables of the new species described herein and selected similar congeners, and the first record for Trypanosyllis zebra in the states of Espírito Santo and Paraíba.

Amblyosyllis, Eusyllis, Odontosyllis, Perkinsyllis and Streptodonta (Annelida: Syllidae) from Brazil, with descriptions of two new species and new records for the country.

We present herein the first records for Amblyosyllis, Eusyllis and Perkinsyllis from northeastern Brazil, describing and illustrating Amblyosyllis sp., Eusyllis kupfferi and E. lamelligera, which are compared to the morphologically most similar congeners; a brief diagnosis is provided for Eusyllis nonatoi, Odontosyllis aracaensis, O. guarauensis, O. guillermoi and Perkinsyllis biota, described from southeastern Brazil. In addition, a new species of Odontosyllis is described, O. brevichaetosa sp. n., characterized by having short, bidentate falciger blades with inverted dorso-ventral gradation in length, and shafts of ventralmost falcigers from midbody parapodia onwards subdistally inflated, with sigmoid tip. A key for the valid Brazilian species of Odontosyllis is provided. Finally, this is also the first account of the genus Streptodonta for the South Atlantic, with the description of S. fauchaldi sp. n., characterized by a distinct distribution pattern of cilia along body, presence of spiniger-like chaetae, and morphology of falciger blades.

The genus Exogone (Polychaeta: Syllidae) from the Brazilian coast, with the description of a new species.

A new species of Exogone, E. gigas sp. n., is described herein, together with E. africana, E. arenosa, E. dispar, E. naidinoides, E. rolani, and E. simplex, collected along the Brazilian coast, including new morphological details. The distribution of E. breviantennata is expanded to include the states of Espírito Santo, Paraíba and Pernambuco. Exogone gigas sp. n. is characterized by having a large median antenna, the absence of dorsal cirri on chaetiger 2, and having a triangular process and minute spines on the shaft of the spiniger-like chaetae on chaetiger 2. The Brazilian specimens are compared to the morphologically most similar congeners. A key for the species described in this paper is provided.

The effect of stocking density on the growth of apple snails native Pomacea bridgesii and exotic Pomacea lineata (Mollusca, Gastropoda).

The demand for alternative food sources is currently in evidence in the world and, therefore, the culture of animal species considered not conventional makes this theme relevant and appropriate. In the present study, the species Pomacea lineata and Pomacea bridgesii, each with three stowage densities (0.5 [T1], 1 [T2], and 1.5 [T3] animal/L), were tested. They were analyzed regarding growth rate, weight gain, final biomass, feed conversion and percentage of survival. There was not any statistically significant difference between the different densities for both species. The final average weight in the three waterworks did not differ significantly in P. bridgesii. In P. lineata, T1 (22.3 ± 1.80g) was significantly higher than T2 and T3. On the other hand, the absolute gain of weight in P. lineata and P. bridgesii was significantly higher in T1 (21.9 ± 1.80g and 37.2 ± 6.34g) than in T2 and T3 respectively. In contrast, the gain of biomass of P. lineata and P. bridgesii was significantly higher in T3 (276.3 ± 33.16g and 431.4 ± 37.20g) than in T1 and T2, respectively. Based on the results obtained, all species studied presented potential for aquaculture, mainly P. bridgesii, distinguished for showing a better development even in waterworks with higher densities.

Species of Odontosyllis Claparède, 1863 (Annelida: Polychaeta: Syllidae) occurring along the Brazlian coast.

Two new species of Odontosyllis were found in samples collected mainly on rocky shores off the states of São Paulo (SE Brazil) and Paraíba (NE Brazil). Odontosyllis aracaensis sp. nov., and O. guarauensis sp. nov., are herein described and compared to their most similar congeners. A key for the species found in Brazil is provided, and relevant morphological characters of similar species of the genus, based on falcigers morphology, are summarized and compared with those of the newly described species. The current state of knowledge on the genus is briefly discussed.