scholarly journals STOMACHICOLA LYCENGRAULIDIS N. SP. (DIGENEA, HEMIURIDAE), PARASITE OF THE ATLANTIC SABRETOOTH ANCHOVY LYCENGRAULIS GROSSIDENS (CLUPEIFORMES, ENGRAULIDAE)

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Ruben Daniel Tanzola ◽  
Silvana Seguel
Keyword(s):  
Relative Size ◽  
Paraná River ◽  
The Body ◽  
Digenetic Trematode ◽  
Buenos Aires Province ◽  
New Taxon ◽  
Bahía Blanca Estuary ◽  
Parana River ◽  
General Terms ◽  
Blanca Estuary

This paper describes and illustrates a new species of digenetic trematode, parasitic in the stomach of the sabretooth anchovy Lycengraulis grossidens (Agassiz, 1829) from the Bahía Blanca estuary and the Paraná River, Argentina, designated as Stomachicola lycengraulidis n.sp. The new taxon differs from S. bayagbonai and S. singhi congeneric species from the Gulf of Guinea and Indian Ocean respectively, mainly in the body size, the structure of the reproductive system, the development of the ecsoma and the sinus sac. It differs from the first one mainly in the presence of two frontal protuberances at the level of the preoral lobe, which are absent in the specimens studied here. Also in general terms, S. bayagbonai is comprised of slightly larger individuals, with larger pharynx, testicles and ovary. And it differs from S. singhi by their smaller duct and hermaphroditic sac and for having a well developed seminal receptacle, which is absent in the Bay of Bengal specimens. When comparing the relative size of the ecsoma, we found significant differences among both of the populations of digeneans examined, the worms collected in the Paraná River was more developed than those from the Bahia Blanca estuary. The host, L. grossidens, migrates to the Paraná river in winter and spring and then, from December to March it makes a trophic migration towards the sea and is found all along the Atlantic coast of Buenos Aires province. For this reason, it is here hypothesized that the relative development of the tail, is affected by environmental conditions, such as pH and osmolarity of the stomach, salinity and/or water temperature.

A new trematode species parasitizing the catfish Hoplosternum littorale (Osteichthyes, Callichthyidae) from Paraná River, Brazil, with an emendation of the diagnosis of Magnivitellinum (Trematoda, Macroderoididae)

2009 ◽  
Vol 54 (1) ◽  
Author(s):  
Ana Lacerda ◽  
Ricardo Takemoto ◽  
Gilberto Pavanelli
Keyword(s):  
Ventral Sucker ◽  
Posterior Margin ◽  
Posterior Extremity ◽  
Relative Size ◽  
Paraná River ◽  
The Body ◽  
Trematode Species ◽  
Generic Diagnosis ◽  
Parana River ◽  
Hoplosternum Littorale

AbstractMagnivitellinum corvitellinum sp. nov. is a parasite from the intestine of tamboatá Hoplosternum littorale, a freshwater catfish from Paraná River, Brazil. This species has an elongate body, a small cirrus-sac, testes in the posterior half of the body and well-developed follicular vitellines. It differs from the only other species in the genus, M. simplex, in having tegumental spines along the body, ventral sucker distinctly bigger than oral sucker, oesophagus absent and vitellaria extending from posterior margin of ventral sucker to near posterior extremity of body. An emendation of the generic diagnosis is proposed in view of the presence of tegumental spines along the body, absence of oesophagus, relative size of ventral and oral suckers and uterus covering caeca from the level of ventral sucker to the end of caeca. This is the fourth trematode species recorded parasitizing Hoplosternum littorale.

scholarly journals Temporal distribution and early development of Moenkausia cf. gracilima (Lucena & Soares, 2016) (Osteichthyes, Characidae) in the upper Paraná River, Brazil

2017 ◽  
Vol 29 (0) ◽  
Author(s):  
Joyce Andreia dos Santos ◽  
Marcia Sayuri Iquematsu ◽  
Claudemir Martins Soares ◽  
Eliana Maria Galdioli ◽  
Klebert Faria da Silva ◽  
...  
Keyword(s):  
Early Development ◽  
Lower Lobe ◽  
Temporal Distribution ◽  
Reproductive Period ◽  
Paraná River ◽  
The Body ◽  
Parana River ◽  
Upper Paraná River Floodplain ◽  
Batch Spawning ◽  
Upper Paraná River

Abstract Aim: To analyze temporal distribution of larvae and juveniles and the early development and of Moenkhausia cf. gracilima. Methods Samples were taken quarterly in twenty-five sites in the upper Paraná River floodplain between August 2013 and May 2015. The samples were taken under the water surface at night using 0.5 mm mesh plankton nets. In the laboratory, samples were sorted, identified and separated into larval (preflexion, flexion and postflexion) and juvenile periods. Results A total of 248 individuals was collected, mainly in the Saraiva Lagoon, suggesting that the entire life cycle of this species occurs in this environment. The reproductive period takes place between December and April, since the postflexion larvae were found until May. However, the occurrence of juveniles between February and May indicates probable batch spawning. Among the 95 individuals used for ontogenic description, 82 were larvae and 13 juveniles. Larvae may be characterized by irregular pigmentation in the upper region of the head, mouth, and body, increasing throughout development; upper lobe of the caudal fin more pigmented than the lower lobe, only visible in postflexion larvae; terminal mouth; anal opening located anterior to the median region of the body and total number of myomers ranging from 34 to 40 (15 to 20 pre and 16 to 23 postanal), while juveniles have characteristics similar to adults. The total number of fin rays is: P. 11-16, V. 7-11, D, 9-11 and A. 21-23. Conclusions According to the distribution of developmental periods it is possible to conclude that this species reproduces in the summer, preferably in lagoons. Growth analysis indicated important alterations in larval morphology (metamorphosis) that may be associated with the ecomorphological characteristics of the species. The morphological separation of larvae of M. cf. gracilima from other larvae of small characids, especially at preflexion and flexion stages may be complicated by the overlap of traits, suggesting the use of other variables, mainly morphometric, for the separation of the species.

scholarly journals Morphological description of the developmental stages of Parauchenipterus galeatus (Linnaeus, 1766) (Siluriformes, Auchenipteridae) on the floodplain of the upper Paraná River

1999 ◽  
Vol 59 (3) ◽  
pp. 429-438 ◽  
Author(s):  
P. V. SANCHES ◽  
K. NAKATANI ◽  
A. BIALETZKI
Keyword(s):  
Developmental Stages ◽  
Paraná River ◽  
The Body ◽  
Morphological Description ◽  
Body Parts ◽  
Morphometric Data ◽  
Double Membrane ◽  
Parana River ◽  
Upper Paraná River ◽  
Development Analysis

We provide morphological and morphometric descriptions of the developmental stages of Parauchenipterus galeatus, from the floodplain of the Upper Paraná River. Specimens were obtained by induced spawning. The species has large adhesive eggs with a double membrane. The incubation period is long, 65 hours at 27°C. The larvae are well developed at hatching, with relatively rapid larval development. Analysis of the morphometric data showed that the body parts of P. galeatus grow proportionately.

Food chain length in a large floodplain river: planktonic or benthic reliance as a limiting factor

2017 ◽  
Vol 68 (7) ◽  
pp. 1336 ◽  
Author(s):  
M. Saigo ◽  
L. Ruffener ◽  
P Scarabotti ◽  
M. Marchese
Keyword(s):  
Chain Length ◽  
Food Chain ◽  
Trophic Position ◽  
Paraná River ◽  
The Body ◽  
Parana River ◽  
Ecosystem Size ◽  
Food Chain Length ◽  
Top Predators ◽  
Middle Paraná

Food chain length (FCL) is a key integrative variable describing ecosystem functioning. The aim of the present study was to test the hypothesis that the relative importance of planktonic and benthic energy pathways is a major factor affecting FCL in the Middle Paraná River. Samples were obtained from in eight waterbodies, measuring chlorophyll-a concentrations and the abundance of benthic invertebrates and the trophic position of top predators by stable isotope analysis. There was no evidence that resource availability, disturbances or ecosystem size limited FCL. Similarly, the body size and trophic position of predators were not correlated. However, the relative abundance of planktonic and benthic resources was correlated with FCL. In addition, stable isotopes analysis showed that the benthic reliance of top predators is correlated with their trophic position. The results of the present study indicate that because the major benthic primary consumer is a large fish (Prochilodus lineatus), the size structure of individual food chains is an important factor determining FCL. Whereas in floodplain rivers large detritivorous fishes are targets of commercial fishing, overfishing in the Middle Paraná River could be expected to increase FCL, the opposite effect to that seen in marine environments.

Dense Bathymetry in Turbid Coastal Zones Using Airborne Hyperspectral Images

2021 ◽  
Vol 87 (12) ◽  
pp. 923-927
Author(s):  
Steven Martinez Vargas ◽  
Claudio Delrieux ◽  
Katy L. Blanco ◽  
Alejandro Vitale
Keyword(s):  
Hyperspectral Images ◽  
Average Error ◽  
Support Vector ◽  
Buenos Aires Province ◽  
Coastal Zones ◽  
Bahía Blanca Estuary ◽  
Data Set ◽  
Spectral Bands ◽  
Unseen Data ◽  
Blanca Estuary

We used airborne hyperspectral images to generate a dense survey of bathymetric data in the Bahía Blanca estuary (Buenos Aires Province, Argentina). This estuarine area is characterized by intense sediment transport turning the water muddy, and thus optical bathymetric estimations are difficult. We used 24 spectral bands in a range of 500–900 nm acquired with a hyperspectral camera aboard an unmanned aerial vehicle, together with 100 bathymetry data points surveyed with a sonar sensor aboard an unmanned surface vehicle, covering an area of about 800 m2. Random-forest and support-vector-machine regressors were trained with this data set. The resulting model yielded a determination coefficient of 0.815 with unseen data, a root-mean-square error of 0.166 m, and an absolute average error less than 2%. These results allow dense and accurate reconstructions of the underwater profile in wide, muddy, shallow regions of the Bahía Blanca estuary, showing the feasibility of hyperspectral imagery combined with sonar data in turbid shallow waters.

scholarly journals Effects of the flood regime on the body condition of fish of different trophic guilds in the Upper Paraná River floodplain, Brazil

2009 ◽  
Vol 69 (2 suppl) ◽  
pp. 469-479 ◽  
Author(s):  
F. Abujanra ◽  
AA. Agostinho ◽  
NS. Hahn
Keyword(s):  
Body Condition ◽  
Food Resources ◽  
Paraná River ◽  
The Body ◽  
Food Sources ◽  
Trophic Guilds ◽  
River Floodplain ◽  
Parana River ◽  
Hydrological Cycles ◽  
Paraná River Floodplain

In this study, we evaluated the influence of various hydrological cycles on the feeding body condition of fish species of different trophic guilds in the Paraná River floodplain, as well as the impacts of upstream impoundments on fish conditions. Attributes of the river floods (duration, time of year, intensity, and variability in a given year) and the body condition, measured by the mean residuals of length-weight ratios, of the detritivorous, herbivorous, insectivorous, invertivores, omnivorous, piscivorous, and planktivorous species were evaluated. Fish were sampled during a period before (1986-1994) and after (2000-2004) the completion of filling of the Porto Primavera Reservoir, which is located upstream from the floodplain area under study. Three sub-basins in the floodplain were sampled: the Ivinheima River, which has no dams; the Paraná River, which has several dams; and the Baia River, which is influenced by the Paraná. A two-way ANOVA identified significant variations in mean body conditions for localities and for the hydrological cycles, and the interactions were also significant. The findings revealed that before the Porto Primavera Reservoir was filled, the body condition of the feeding guilds varied similarly in the three sub basins, but this pattern was not observed after filling was completed. However, in years with minor or no floods, the body condition was high, especially in the sub-basins influenced by Porto Primavera (Paraná and Baía). Pearson's and Spearman's correlations showed that most effects of the floods were unfavorable to the body condition of the guilds, except for the annual variation in water level, which aids herbivores in accessing allochthonous food resources. Detritivores were negatively affected by all flood attributes. A correlation between the relative stomach weight (mean residual of the ratio of total and stomach weights) and the body condition demonstrated the poor relationship between the amount of food intake and weight gain; insectivores were the exception, showing a significant negative correlation. Therefore, for this guild, there is evidence that their food sources during floods have low nutritional value. It is hypothesized that dry years lead to improvement in the nutritional quality of food resources, and that the water released from the upstream dam dilutes and removes these resources without providing new food inputs. This exacerbates the effects of floods on body conditions.

scholarly journals Stranded humpback whale (Megaptera novaeangliae) (Cetacea: Balaenopteridae) in Paraná River Delta, Buenos Aires Province, Argentina. Comments on the occurrence of marine mammals in the La Plata River Basin

2018 ◽  
Vol 58 ◽  
pp. 1 ◽  
Author(s):  
Sergio O. Lucero ◽  
María Constanza Gariboldi ◽  
Valeria Bauni ◽  
Juan Manuel Meluso ◽  
Daniela Del Castillo ◽  
...  
Keyword(s):  
River Basin ◽  
Marine Mammals ◽  
Buenos Aires ◽  
Humpback Whale ◽  
Paraná River ◽  
Megaptera Novaeangliae ◽  
River Delta ◽  
Buenos Aires Province ◽  
La Plata ◽  
Parana River

The humpback whale (Megaptera novaeangliae) is distributed among most oceans and seas of the globe (except Mediterranean Sea). These whales migrate from feeding regions in the Antarctic waters to breeding areas in tropical and subtropical seas. Here we report the stranding of a female young humpback whale, which was founded dead in the vicinity of the Talavera Island, in the Paraná River Delta, Buenos Aires Province, Argentina. From the analysis of mitochondrial cytochrome c oxidase subunit I gene sequences, two novel haplotypes were found, totalizing four haplotypes described for the species. In the La Plata River Basin this species was found only twice at the end of the XIX century. Thus, the new finding constitutes an important addition to the list of cetaceans that occurs in Uruguay, Paraná and La Plata Rivers.

Staurosirella paranaensis sp. nov., a new epiphytic freshwater diatom (Bacillariophyceae) from the Paraná River floodplain, Brazil, South America

Phytotaxa ◽  
2021 ◽  
Vol 480 (2) ◽  
pp. 163-173
Author(s):  
NICOLLI C. OSÓRIO ◽  
LUC ECTOR ◽  
LILIANA RODRIGUES ◽  
CARLOS E. WETZEL
Keyword(s):  
Morphological Characteristics ◽  
Paraná River ◽  
Similar Species ◽  
New Taxon ◽  
River Floodplain ◽  
Parana River ◽  
Apical Pore ◽  
Eichhornia Azurea ◽  
Upper Paraná River Floodplain ◽  
Paraná River Floodplain

A new diatom species, Staurosirella paranaensis, is described only from epiphytic samples on the macrophyte Eichhornia azurea in a lake from the Upper Paraná River Floodplain in Brazil. Description of the new taxon is based on morphological characteristics observed using light and scanning electron microscopy. The new species is characterized by short elliptic valves with an axial area narrowly lanceolate, sometimes giving the impression of having a zig-zag form due the alternating nature of the striae. The lineolate striae, running uninterrupted from valve face to mantle. Spines are solid, thin, spatulate with two prominences at the top, located at the costae. Apical pore fields are inconspicuous, located at both apices and equally developed on both valves. Girdle elements variable in number, open, lacking pores, ligulated, and with valvocopula being much larger. The species previously identified in the region as the “catch-all” taxon “Staurosirella (Staurosira) pinnata” is placed in the genus Staurosirella based on the striae bearing well-developed internal vimines delimiting typically long areolae. Comparisons with similar species ascribed to the genus Staurosirella are provided to highlight the peculiar characteristics of S. paranaensis.

scholarly journals Radiocarbon Reservoir Ages and Hardwater Effect for the Northeastern Coastal Waters of Argentina

Radiocarbon ◽  
2008 ◽  
Vol 50 (1) ◽  
pp. 119-129 ◽  
Author(s):  
Eduardo A Gómez ◽  
C Marcela Borel ◽  
Marina L Aguirre ◽  
Daniel E Martínez
Keyword(s):  
Mass Spectrometry ◽  
Calibration Curve ◽  
Coastal Waters ◽  
Buenos Aires ◽  
Buenos Aires Province ◽  
Layer Model ◽  
Bahía Blanca Estuary ◽  
Radiocarbon Dates ◽  
The Difference ◽  
Blanca Estuary

Accelerator mass spectrometry (AMS) radiocarbon dates were obtained for 18 mollusk shells collected alive along the Buenos Aires province coast, Argentina, over the period AD 1914–1935. Reservoir ages were estimated for all samples on the basis of the tree-ring calibration curve for the Southern Hemisphere (SHCal04, McCormac et al. 2004) and the marine δR values calculated as the difference between the conventional 14C age and the age deduced from the marine, mixed-layer model calculation (Marine04, Hughen et al. 2004). For most coastal locations, a great δR scatter was observed, ranging from 191 to 2482 yr, which is explained by the input of varying content of dissolved carbonate by rivers and groundwater (“hardwater effect”) and indicates a serious limitation for shell-based 14C chronologies. Within the interior of Bahía Blanca estuary, δR values ranged from −40 to 50 ± 46 as a consequence of the local geological particularities of the environment. This suggests that, with some restrictions, the marine calibration curve with standard parameters (δR = 0) could be used at this location.

Description of Ptilohyale corinne sp. nov. (Amphipoda: Hyalidae) from the Bahía Blanca estuary, Argentina, including a key to all valid Ptilohyale species

Zootaxa ◽  
2020 ◽  
Vol 4763 (1) ◽  
pp. 125-137
Author(s):  
CATALINA DI ROSSI ◽  
MICHEL SCIBERRAS ◽  
VERONICA N. BULNES
Keyword(s):  
New Species ◽  
South America ◽  
Buenos Aires ◽  
First Record ◽  
Valid Species ◽  
Buenos Aires Province ◽  
Bahía Blanca Estuary ◽  
A New Species ◽  
Blanca Estuary

A new species of amphipod, Ptilohyale corinne sp. nov. (Hyalidae) is described from the Bahía Blanca estuary (38°53’S, 62°07’W) in Buenos Aires Province, Argentina. Ptilohyale corinne sp. nov. can be differentiated from its valid congeners by having two posterior marginal cusps on coxa 2 and 3, and asymmetrical telson lobes with a particular combination of setae: each lobe with three dorsal plumose setae and one seta on inner margin. This is the first record of Ptilohyale in South America. Additionally a key to the valid species of the genus is provided 

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