Distribution patterns of loliginid squid paralarvae in relation to the oceanographic features off the South Brazil Bight (22°-25°S)

2017 ◽  
Vol 27 (1) ◽  
pp. 63-75 ◽  
Author(s):  
Carolina Costa de Araujo ◽  
Maria A. Gasalla
Keyword(s):  
Distribution Patterns ◽  
The South ◽  
Loliginid Squid ◽  
South Brazil

scholarly journals The trophic role of the squid Loligo plei as a keystone species in the South Brazil Bight ecosystem

2010 ◽  
Vol 67 (7) ◽  
pp. 1413-1424 ◽  
Author(s):  
Maria A. Gasalla ◽  
Amanda R. Rodrigues ◽  
Felippe A. Postuma
Keyword(s):  
Keystone Species ◽  
Stomach Contents ◽  
The South ◽  
Fish Prey ◽  
Loliginid Squid ◽  
Trophic Impact ◽  
South Brazil ◽  
Energy Pathways ◽  
Trophic Role

Abstract Gasalla, M. A., Rodrigues, A. R., and Postuma, F. A. 2010. The trophic role of the squid Loligo plei as a keystone species in the South Brazil Bight ecosystem. – ICES Journal of Marine Science, 67: 1413–1424. The issue of whether loliginid squid can influence the average structure of marine ecosystems in a keystone role, i.e. a strong effect with relatively low biomass, has not yet been examined. Here, the diet of Loligo plei in inner shelf waters of the South Brazil Bight was examined, as a first step, based on the stomach contents of 2200 squid hand-jigged in shallow water (<30 m) and taken as bycatch of shrimp trawlers in deeper water (30–100 m). Diet varied by size, season, and fishing zone. Stomachs were not empty in ∼12%, with more empty during winter. The range of mantle lengths of squid caught by jigging (101–356 mm) appeared to differ from the squid trawled (30–236 mm), and the diet also differed. Food categories recorded in deeper water did not include amphipods or polychaetes, but in both fishing areas, fish were the most common prey. The fish prey identified included Trachurus lathami, small pelagic species, trichiurids, and Merluccius hubbsi. Demersal species, such as Ctenosciaena gracilicirrhus, and flatfish were also present. An ecosystem network model is updated through which a mixed-trophic impact matrix and “keystoneness” indicators were calculated. Loligo plei represents an important link between pelagic and demersal energy pathways, with high indices of keystoneness.

scholarly journals Climate variability impacts on diversification processes in a biodiversity hotspot: a phylogeography of ancient pseudoscorpions in south-western Australia

2019 ◽  
Vol 186 (4) ◽  
pp. 934-949 ◽  
Author(s):  
Danilo Harms ◽  
J Dale Roberts ◽  
Mark S Harvey
Keyword(s):  
Phylogenetic Analyses ◽  
Distribution Patterns ◽  
Biodiversity Hotspot ◽  
Molecular Dating ◽  
Environmental Niche ◽  
Ecological Niche Models ◽  
The South ◽  
Niche Modelling ◽  
South West ◽  
Western Division

Abstract The south-western division of Australia is the only biodiversity hotspot in Australia and is well-known for extreme levels of local endemism. Climate change has been identified as a key threat for flora and fauna, but very few data are presently available to evaluate its impact on invertebrate fauna. Here, we derive a molecular phylogeography for pseudoscorpions of the genus Pseudotyrannochthonius that in the south-west are restricted to regions with the highest rainfall. A dated molecular phylogeny derived from six gene fragments is used for biogeographic reconstruction analyses, spatial mapping, environmental niche-modelling, and to infer putative species. Phylogenetic analyses uncover nine clades with mostly allopatric distributions and often small linear ranges between 0.5 and 130 km. Molecular dating suggests that the origins of contemporary diversity fall into a period of warm/humid Palaeogene climates, but splits in the phylogeny coincide with major environmental shifts, such as significant global cooling during the Middle Miocene. By testing several models of historical biogeography available for the south-west, we determine that Pseudotyrannochthonius is an ancient relict lineage that principally follows a model of allopatric speciation in mesic zone refugia, although there are derivations from this model in that some species are older and distribution patterns more complex than expected. Ecological niche models indicate that drier and warmer future climates will lead to range contraction towards refugia of highest rainfall, probably mimicking past variations that have generated high diversity in these areas. Their conservation management will be crucial for preserving the unique biodiversity heritage of the south-west.

Comparative anatomy of the gut of the South American species of Amitermes, with description of two new species and an identification key based on soldiers and workers

Zootaxa ◽  
2020 ◽  
Vol 4751 (1) ◽  
pp. 75-104
Author(s):  
MAURICIO M. ROCHA ◽  
ELIANA M. CANCELLO
Keyword(s):  
New Species ◽  
South America ◽  
Geographic Distribution ◽  
Comparative Anatomy ◽  
Distribution Patterns ◽  
South American ◽  
The South ◽  
South American Species ◽  
Two New Species ◽  
First Time

In this contribution we present updates on the taxonomy and morphology of the South American species of Amitermes. Two new species are described: Amitermes bandeirai, sp. n., from Brazil, and Amitermes lilloi, sp. n., from Argentina. Amitermes nordestinus is a junior synonym of Amitermes aporema. The imago of A. aporema is described for the first time. Detailed comparative gut anatomy of the eight species is presented for the first time. The geographic distribution of Amitermes in South America is expanded and the distribution patterns of some species are discussed. 

scholarly journals Carbon Flow for Plankton Metabolism of Saco do Mamanguá Ría, Bay of Ilha Grande, a Subtropical Coastal Environment in the South Brazil Bight

2019 ◽  
Vol 6 ◽  
Author(s):  
Frederico Brandini ◽  
Luan Sayeg Michelazzo ◽  
Gabriel Ruske Freitas ◽  
Giulia Campos ◽  
Mateus Chuqui ◽  
...  
Keyword(s):  
Coastal Environment ◽  
Carbon Flow ◽  
The South ◽  
South Brazil

scholarly journals The use of the South African Diatom Index as a concervation management tool for Hewitt’s Ghost frog

2012 ◽  
Vol 31 (1) ◽  
Author(s):  
V. Botha ◽  
C. Weldon ◽  
J.C. Taylor
Keyword(s):  
South African ◽  
Distribution Patterns ◽  
Management Tool ◽  
The South ◽  
Diatom Index ◽  
The Impact

Distribution patterns of diatoms were investigated to determine the impact ofshading on the distribution of diatomes, which form the main diet of the endangered frogspecies, Heleophryne hewitti.

New archeointensity data from South Brazil and the influence of the South Atlantic Anomaly in South America

2019 ◽  
Vol 512 ◽  
pp. 124-133
Author(s):  
Gelvam A. Hartmann ◽  
Wilbor Poletti ◽  
Ricardo I.F. Trindade ◽  
Lucio M. Ferreira ◽  
Pedro L.M. Sanches
Keyword(s):  
South America ◽  
South Atlantic ◽  
The South ◽  
South Atlantic Anomaly ◽  
South Brazil

Regional distribution patterns of chemical parameters in surface sediments of the south-western Baltic Sea and their possible causes

2017 ◽  
Vol 37 (6) ◽  
pp. 593-606 ◽  
Author(s):  
T. Leipe ◽  
M. Naumann ◽  
F. Tauber ◽  
H. Radtke ◽  
R. Friedland ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Surface Sediments ◽  
Regional Distribution ◽  
Distribution Patterns ◽  
Chemical Parameters ◽  
The South

scholarly journals The influence of the Brazil and Malvinas Currents on the Southwestern Atlantic Shelf circulation

Ocean Science ◽  
2010 ◽  
Vol 6 (4) ◽  
pp. 983-995 ◽  
Author(s):  
R. P. Matano ◽  
E. D. Palma ◽  
A. R. Piola
Keyword(s):  
World Ocean ◽  
Deep Ocean ◽  
Western Boundary ◽  
Oceanic Circulation ◽  
Southwestern Atlantic ◽  
The South ◽  
Wind Speeds ◽  
The North ◽  
Brazil Current ◽  
South Brazil

Abstract. The oceanic circulation over the southwestern Atlantic shelf is influenced by large tidal amplitudes, substantial freshwater discharges, high wind speeds and – most importantly – by its proximity to two of the largest western boundary currents of the world ocean: the Brazil and Malvinas currents. This review article aims to discriminate the dynamical processes controlling the interaction between this extensive shelf region and the deep-ocean. The discussion is focused on two broad regions: the South Brazil Bight to the north, and Patagonia to the south. The exchanges between the Brazil Current and the South Brazil Bight are characterized by the intermittent development of eddies and meanders of the Brazil Current at the shelfbreak. However, it is argued that this is not the only – nor the most important – influence of the Brazil Current on the shelf. Numerical simulations show that the thermohaline structure of the South Brazil Bight can be entirely ascribed to steady state, bottom boundary layer interactions between the shelf and the Brazil Current. The Malvinas Current does not show the development of eddies and meanders, but its influence on the Patagonian shelf is not less important. Models and observations indicate that the Malvinas Current not only controls the shelfbreak dynamics and cross-shelf exchanges but also influences the circulation in the shelf's interior.

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