Distribution and abundance of the Lesser electric ray Narcine brasiliensis (Olfers, 1831) (Elasmobranchii: Narcinidae) in southern Brazil in relation to environmental factors

The distribution and abundance of the lesser electric ray, Narcine brasiliensis, was assessed based on bottom-trawl survey data collected off the coast of Rio Grande do Sul, southern Brazil. Between 1980 and 1984 and in 2005, 416 bottom trawl hauls were carried out at depths of 10-100 m. Narcine brasiliensis occurred mainly in waters with bottom temperature between 20 and 25ºC. Density of the species was higher between the depths of 10 and 20 m, during the summer and autumn. The seasonal pattern of N. brasiliensis in the shallow coastal water of Rio Grande do Sul reflects a southward migration in summer. This is conditioned by the southward advance of warmer and high-salinity Tropical Water of the Brazil Current In winter, the return or northward migration is a response to seasonal cooling of the coastal waters and to the northward advance of cold Coastal Water of lower salinity. The latitudinal gradient in density of N. brasiliensis was related to the latitudinal gradient in salinity of the bottom waters. This was caused by the freshwater runoff from the Patos Lagoon establishing a physical barrier to the occurrence of the species farther south than the city of Rio Grande.

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Ecological analogies between estuarine bottom trawl fish assemblages from Patos Lagoon, Rio Grande do Sul, Brazil and York River, Virginia, USA

Revista Brasileira de Zoologia ◽

10.1590/s0101-81752006000100017 ◽

2006 ◽

Vol 23 (1) ◽

pp. 234-247 ◽

Cited By ~ 19

Author(s):

João P. Vieira

Keyword(s):

Fish Assemblages ◽

Seasonal Pattern ◽

Rio Grande ◽

Abundant Species ◽

Size Class ◽

Bottom Trawl ◽

Estuarine Fish ◽

Rio Grande Do Sul ◽

York River ◽

Patos Lagoon

The structure of estuarine fish assemblages at temperate latitudes in Patos Lagoon (32º05'S, 52º04'W), Rio Grande do Sul, Brazil and York River (37º17'N, 76º33'W), Virginia, USA was compared using mid and late 1970's data from bottom trawl collection to investigate whether geographically isolated fish assemblages have similar ecological structure given similar latitudinal positions on the warmtemperate southwestern and northwestern Atlantic regions, respectively. Since estuarine species often exhibit an ontogenetic shift in habitat requirements or preferences we examined Capture per Unity of Effort by size class (CPUE-SC) and split species into "size ecological taxa" (SET) for analysis. The use of CPUE-SC also allowed the abundance of a SET to be computed by summing the mean CPUE of each size class within that SET and use this information to follows SET's temporal and or spatial abundance. A total of 65 and 63 species was collected during a year of bottom trawling in the Patos Lagoon and York River estuaries, respectively. In both localities the strongest modal size class was < 80 mm TL, and several abundant species were smaller than 100 mm TL. The size between 80 and 100 TL effectively separated several species into discrete SET's in both systems. Those SET's could have different ecological preferences, temporal and spatial distributions and so identified as different "ecological taxa". In warm months, when predation by large fish is most likely, the abundance of fish between 80 and 100 mm TL in "bottom trawl" demersal fish assemblages was low in both systems. Only the sea catfishes, in Patos Lagoon, protected by strong dorsal and pectoral spines, and the Hogchoker, in the York River, protected by burrowing in the bottom substrate, peak in abundance at this size class. The seasonal pattern of estuarine use was similar between localities and did not differ from other warm-temperate estuarine fish assemblages.

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Reproductive biology of Menticirrhus littoralis in southern Brazil (Actinopterygii: Perciformes: Sciaenidae)

Neotropical Ichthyology ◽

10.1590/s1679-62252004000100005 ◽

2004 ◽

Vol 2 (1) ◽

pp. 31-36 ◽

Cited By ~ 5

Author(s):

Aloisio Sirangelo Braun ◽

Nelson Ferreira Fontoura

Keyword(s):

Reproductive Biology ◽

Seasonal Pattern ◽

Gonadosomatic Index ◽

Rio Grande ◽

Minimum Size ◽

Northern Coast ◽

Southern Brazil ◽

Rio Grande Do Sul ◽

Commercial Fish ◽

Total Length

Menticirrhus littoralis is an important sport and commercial fish species in southern Brazil. This paper aims to analyze the reproductive biology of the species in Rio Grande do Sul coastal waters. Captures were carried out at Cidreira's fishing pier (30º 08' S; 50º 11' W) located on the Northern Coast of Rio Grande do Sul, where sport-fishing takes place throughout the year. Sport fishermen using hook-and-line with different hook sizes and varied baits exclusively made the captures. A total of 807 individuals were obtained from June 1997 to May 1998. Sexual proportion was 0.67 female for each male (323 females and 484 males; chi2c = 32.120; DF=1; P<0.001). The smallest individual (total length) for captured animals was a male of 13 cm whereas the largest was a female of 46 cm. The minimum size (total length) for a mature female was 19.8 cm. The size at first maturation (L50) was 23 cm and females larger than 27 cm spawned at least once (L100). The reproductive period for M. littoralis is from September to March. Gonadosomatic index (GSI) showed a clear seasonal pattern. Mean ovarian weight was highest in November when it reached 5% of total body weight. Apparently, there is a size gradient for M. littoralis in the area. Larger individuals inhabit deeper water, and they move to the coast mainly for spawning.

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Distribution, abundance and morphometry of Atlantoraja cyclophora (Regan, 1903) (Elasmobranchii: Rajidae) in southern Brazil, Southwestern Atlantic

Neotropical Ichthyology ◽

10.1590/s1679-62252004000300005 ◽

2004 ◽

Vol 2 (3) ◽

pp. 137-144 ◽

Cited By ~ 14

Author(s):

María Cristina Oddone ◽

Carolus Maria Vooren

Keyword(s):

Sex Ratio ◽

Rio Grande ◽

Bottom Trawl ◽

Frequency Of Occurrence ◽

Southwestern Atlantic ◽

Southern Brazil ◽

Rio Grande Do Sul ◽

Total Length

A total of 459 individuals of Atlantoraja cyclophora were captured along the Rio Grande do Sul coast between latitudes 30º40'S and 34º30'S. Two surveys were performed, in the winter 2001 and in the summer/autumn 2002, using bottom-trawl between the depths of 100 and 600 m. This species occurred between 100 and 300 m deep, without significant differences in the frequency of occurrence and abundance (CPUE; kg/hour) between latitudes, depth and seasons. The sex ratio was not significantly different from 1:1 in all depths. In the study area, temperature ranged between 10.0 ºC and 17.6 ºC and salinity between 35.2 e 36.0 ppm. There was no correlation between CPUE and depth, temperature and salinity. Mean total length of females (53.2 cm) was significantly larger than males (50.9 cm). No differences were detected in mean total length between seasons, but mean total length was significantly larger in depths of 100 m and 200 m. The distribution of the frequencies of total length was asymmetric, indicating rareness or lack of juveniles in the samples.

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Description of Two New Species of the Genus Vorticella (Ciliophora: Peritrichia) Epibionts on Pomacea canaliculata (Mollusca: Ampullariidae: Gastropoda) in Southern Brazil

Zootaxa ◽

10.11646/zootaxa.4508.2.4 ◽

2018 ◽

Vol 4508 (2) ◽

pp. 211

Author(s):

MARCOS W. O. PEREIRA ◽

FABIANO CARVALHO De BRITO ◽

EDUARDO EIZIRIK ◽

LAURA R. P. UTZ

Keyword(s):

New Species ◽

Rio Grande ◽

The Other ◽

Pomacea Canaliculata ◽

Regular Pattern ◽

Southern Brazil ◽

Rio Grande Do Sul ◽

Patos Lagoon ◽

Two New Species ◽

Scanning Electron

The peritrich ciliates Vorticella veloxiiforme n.sp. and Vorticella ampullaria n.sp. were found as epibionts on the ampullarid mollusk Pomacea canaliculata collected from Patos Lagoon, Rio Grande do Sul state, Brazil. The detailed morphology of both species was investigated using live and stained specimens, as well as scanning electron microscopy. Zooids of Vorticella veloxiiforme are cup shaped measuring 57 X 41 μm on average. A J-shaped macronucleus lies in the upper half of the cell. One contractile vacuole was observed in the upper part of the cell. V. ampullaria presents an elongate zooid measuring 70 X 25 µm on average. A C-shaped macronucleus lies in the middle of the cell. Two contractile vacuoles are present: one close to the peristome and the other in the lower half of the cell. The pattern of oral polykinetids was typical of the genus, with all infundibular polykinetids composed by three rows of kinetosomes each. SEM revealed a regular pattern of pores present on the zooid membrane of both species. Analyses of the 18s rDNA placed the two new species in the order Vorticellida close to described species of Vorticella.

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Gauchergasilus euripedesi (Copepoda, Ergasilidae) parasitizing different species of fish from two environments in southern Brazil

Neotropical Biology and Conservation ◽

10.3897/neotropical.16.e64668 ◽

2021 ◽

Vol 16 (2) ◽

pp. 289-298

Author(s):

Moisés Gallas ◽

Laura R. P. Utz

Keyword(s):

Electron Microscopy ◽

Fish Species ◽

Rio Grande ◽

Parasitic Copepod ◽

Southern Brazil ◽

Rio Grande Do Sul ◽

Porto Alegre ◽

Patos Lagoon ◽

Estuarine Area ◽

Scanning Electron

The parasitic copepod Gauchergasilus euripedesi (Montú, 1980) Montú & Boxshall, 2002 was described from plankton samples and specimens found in four fish species from the estuarine area of Patos Lagoon, state of Rio Grande do Sul (RS), Brazil. Later, one different fish species was reported parasitized with G. euripedesi in the same locality. Species of Astyanax Baird & Girard, 1854 (Astyanax henseli Melo & Buckup, 2006 and Astyanax lacustris (Lütken, 1875)) and Psalidodon Eigenmann, 1911 (Psalidodon eigenmanniorum (Cope, 1894) and Psalidodon aff. fasciatus (Cuvier, 1819)) were collected in two environments (Pintada Island, municipality of Porto Alegre and Itapeva Lagoon, municipality of Terra de Areia, RS) to investigate their parasites. The copepods found in the gill arches were counted, processed, mounted in permanent slides, and photographed using light microscopy, or processed for observation in scanning electron microscopy. Specimens of P. eigenmanniorum from Pintada Island, A. lacustris and P. aff. fasciatus from Itapeva Lagoon, were parasitized by G. euripedesi, with prevalences of 29.03% (A. lacustris), 10.34% (P. eigenmanniorum), and 9.68% (P. aff. fasciatus). Measurements obtained for specimens of G. euripedesi were similar to those found in the literature, except for egg sacs which were larger in the specimens examined in the present study. In addition to being the first report of G. euripedesi parasitizing species of fish (A. lacustris, P. eigenmanniorum, and P. aff. fasciatus), the results presented here also extend the known geographic distribution of the copepod species.

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The DiatomAnorthoneis dulcisHein from Southern Brazil: Morphology and Ecology

Research Letters in Ecology ◽

10.1155/2008/140245 ◽

2008 ◽

Vol 2008 ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

Garcia Marinês ◽

Talgatti Dávia Marciana

Keyword(s):

Fine Structure ◽

South America ◽

Relative Abundance ◽

Environmental Parameters ◽

Rio Grande ◽

Southern Brazil ◽

Rio Grande Do Sul ◽

Patos Lagoon ◽

Original Diagnosis ◽

Structure Morphology

A new geographic locality forAnorthoneis dulcisis reported. The paper describes the distribution and relative abundance ofA. dulcisin Lagoa dos Patos lagoon (a lagoon in Rio Grande do Sul state, Brazil) from samples collected between 2004 and 2005, and shows that this rare species is present all year round. This study extends the species distribution to South America indicating that the species can thrive on sand grains in lentic estuarine, and freshwater areas. It widens the range of tolerance to environmental parameters. The valve fine structure, morphology, and dimensions are in agreement with the original diagnosis.

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The fish fauna of the Corrientes stream basin, Patos lagoon system, state of Rio Grande do Sul, southern Brazil

Check List ◽

10.15560/8.1.077 ◽

2012 ◽

Vol 8 (1) ◽

pp. 077 ◽

Cited By ~ 7

Author(s):

Matheus Vieira Volcan ◽

Luis Esteban Krause Lanés ◽

Ândrio Cardozo Gonçalves ◽

Alinca Peres da Fonseca ◽

Maximiano Pinheiro Cirne

Keyword(s):

Fish Fauna ◽

Rio Grande ◽

System State ◽

Southern Brazil ◽

Rio Grande Do Sul ◽

Patos Lagoon ◽

Lagoon System

The fish sampled in this study were captured in seasonal collections samplings, conducted between May 2006 and February 2007 in 15 stretches of the Corrientes stream basin, Patos lagoon system, Rio Grande do Sul state, Brazil. A total of 8088 specimens were collected, belonging to nine orders, 24 families and 68 species. In general, the ichthyofauna in this basin has the same pattern recognized for Neotropical rivers with predominance of Characiformes and Siluriformes orders and a high representative of the Characidae and Loricariidae families.

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Pisces, Perciformes, Gobiidae, Ctenogobius stigmaticus (Poey, 1860): new species record at Patos Lagoon estuary, state of Rio Grande do Sul, Brazil

Check List ◽

10.15560/6.1.056 ◽

2010 ◽

Vol 6 (1) ◽

pp. 056 ◽

Cited By ~ 5

Author(s):

Marcelo Dias de Mattos Burns ◽

Alexandre Miranda Garcia ◽

João Paes Vieira

Keyword(s):

New Species ◽

Present Note ◽

Rio Grande ◽

Southern Brazil ◽

Rio Grande Do Sul ◽

Patos Lagoon ◽

Gobiid Fish ◽

Patos Lagoon Estuary ◽

First Time

The present note records for the first time the gobiid fish Ctenogobius stigmaticus (Poey, 1860) at Patos Lagoon stuary, state of Rio Grande do Sul, southern Brazil. The known distribution of this species is therefore extended 600 km southwards.

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