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This paper reports the first record of the endangered cerianthid Ceriantheomorphe brasiliensis in the State of Paraná, southern Brazil. The observed distribution of the species over Paranaguá Bay is described and some aspects of its conservation are discussed.

In this article, our knowledge of the geographic distribution of Grania species is expanded by describing seven new species, Grania bekkouchei sp. nov., Grania brasiliensis sp. nov., Grania capensis sp. nov., Grania chilensis sp. nov., Grania cryptica sp. nov., Grania hinojosai sp. nov., and Grania simonae sp. nov., from poorly investigated regions of the Southern Hemisphere, plus two new species, Grania carolinensis sp. nov. and Grania unitheca sp. nov., from off the east coast of the USA. An immature achaetous specimen that we call Grania cf. levis was also included. The newly generated data were combined with a previously published data set in order to update the hypothesis of phylogenetic relationships among Grania species. All new species except G. cryptica sp. nov. are supported by both morphological and molecular data. In addition, we find that G. chilensis sp. nov. is structured in at least four distinct populations along the Chilean coast. The species described from South Africa form a monophyletic clade where two are morphologically indistinguishable but diverging in both mitochondrial and nuclear ribosomal genes, and thus we describe them as different species, G. bekkouchei sp. nov. and G. cryptica sp. nov. Among the North Carolinian species, G. unitheca sp. nov. is indicated as a close relative of Grania monospermatheca Erséus & Lasserre, 1976, and G. carolinensis sp. nov. is indicated as a close relative of G. cf. levis. The updated phylogeny is strongly concordant with geographical species distributions, thus supporting a low level of dispersal within this genus, as has previously been hypothesized. © 2015 The Linnean Society of London

Bottom trawling is a large-scale fishing activity along the Brazilian coast, but its effects on benthic infauna are still poorly known. This is the first experimental evaluation of benthic responses to bottom trawling along the Brazilian coast. We tested the effects of trawling on macroinfaunal assemblages on the inner continental shelf off Paraná (southern Brazil) by using a sampling design with adjacent trawl and control areas. We hypothesized that if trawl fishing has a negative effect then we should expect lower numbers of species and lower benthic densities after an experimental trawling. Sampling was conducted at adjacent sites within each area to minimize confounding due to spatial variation. Five sites were sampled at a control, and five at an experimental area for infaunal and sedimentological variables. Sampling was carried out just before and one hour after experimental trawling. Multidimensional scaling followed by a PERMANOVA did not show any clear variation tendencies in the structure of the benthic assemblages in the impacted area before and after trawling. However, variance analysis showed a significant and unexpected increase in infaunal total density, in the density of the numerically dominant species (except for the polychaetes Capitella sp. and Loandalia tricuspis) and in species richness in the experimental area. Conversely, no significant variations were recorded in the control area. We suggest that the overall increase in benthic density after a disturbance is correlated with the reworking of the sediment matrix and benefits the suspension-feeders after sediment resuspension.

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Marine oligochaetous clitellates are poorly investigated in the South Atlantic Ocean, especially along the east coast of South America. Closely related species are often difficult to distinguish based on morphology. The lack of specialists and modern identification guides have been pointed out as the main reasons for the scarcity of studies in the South Atlantic Ocean as a whole. To increase the knowledge of this group in the South Atlantic, the genetic diversity of a sample of marine oligochaetous clitellates from Brazil, South Africa and Antarctica was assessed by the Automatic Barcode Gap Discovery (ABGD) and the generalised mixed Yule coalescent (GMYC) approaches. In total, 80 cytochrome c oxidase subunit I (COI) sequences were obtained, each with ~658bp, estimated to represent 32 distinct putative species. ABGD established a barcoding gap between 3% and 14% divergence for uncorrected p-distances and the estimates of GMYC were largely concordant. All the clusters or putative species were genetically associated with previously known species or genera. This study thus confirms the adequacy of the COI barcoding approach combined with a genetic divergence threshold at the order of 10% for marine oligochaetous clitellates.

Marionina Michaelsen, 1890 is a polyphyletic enchytraeid genus represented by about 100 nominal species (Rota et al., 2008). When the genus was originally described in 1889, it got a preoccupied name, Marionia, which was corrected into Marionina one year later by Michaelsen himself. According to the ICZN (1999: Art. 60.3), a new replacement name has its own author and date. Thus, the correct nomenclature of the genus should be Marionina Michaelsen, 1890 (Rota et al., 2008).

Enchytraeid worms collected in South Africa and on the Marion, South Orkney, South Georgia and South Shetland Islands during 2008–2015 were studied using morphology and seven genetic markers. Nine species were recognized: one terrestrial (Christensenidrilus blocki) and all the others marine littoral (five Lumbricillus and three Marionina s.s.). An estimated phylogeny including other enchytraeids from the Northern Hemisphere, many of which are members of Lumbricillus and some representing Marionina s.l., confirmed a non-monophyletic Lumbricillus, with some of its current species closely related to Grania or Marionina s.s. The phylogeny also corroborated a non-monophyletic Marionina s.l., with Marionina s.s. closely related to Grania and Lumbricillus s.l., but not to the remaining sequenced ‘Marionina’ or to Ch. blocki. These results provide a long-needed starting point for a revision of both Marionina and Lumbricillus. We provide morphological descriptions of all nine species, three of which are new to science: Lumbricillus finisafricae sp. nov., Lumbricillus nivalis sp. nov., and Marionina fusca sp. nov. Comments on three related species of Marionina s.s. based on re-examined type material are also provided.