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1.
Environ Monit Assess ; 192(10): 668, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33005999

RESUMO

Watershed morphometric assessment is about measurements and calculations of land surface forms for the purpose of understanding hydro-geomorphological character and patterns. Important natural environment geo-information and summary of the spatial characteristics of Tana River Basin (TRB) in Kenya have been obtained through hydro-geomorphometric analysis. Advanced Spaceborne Thermal Emission and Reflection Radiometer Digital Elevation Model (ASTERDEM) data and ArcGIS (ESRI Inc., version 10.4.1) together with published mathematical equations were applied to extract morphometric parameters of the drainage basin, which covers a total area of 94,930 km2 and a span of 527.75 km. The quantitative morphometric analysis considered a total of 28 relief, areal, and linear hydro-morphometric characteristics of the TRB. Relief parameters of the basin suggest moderate-to-low overall watershed steepness, upland with rolling land surface patterns, rugged landforms susceptible to erosion and sediment transportation, and a landscape in evolution process tending towards maturity. This means stability of the land surface can be attained with intensive land degradation reversing strategies like erosion control measures. Areal characteristics further support the basin's susceptibility to erosion as shown by stream length, stream drainage density, and circulatory ratio values. Also, the areal aspects portray peak runoffs with short duration flashes. Linear parameter value results such as bifurcation ratio imply that infiltration capacity varies with stream orders across the watershed. This hydro-geomorphometric analysis would be useful to land and water managers, researchers and practitioners of TRB, and other similar systems in designing and planning soil and water conservation and management practices such as soil erosion control, groundwater recharge activities, catchment modelling, runoff and flood studies, prospecting groundwater mapping, and biological applications.


Assuntos
Monitoramento Ambiental , Sistemas de Informação Geográfica , Quênia , Rios , Solo
2.
Zootaxa ; 4819(1): zootaxa.4819.1.5, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-33055672

RESUMO

Vanmanenia intermedia, which has long been synonymized with V. pingchowensis since 1980, is here revalidated using morphological characters and molecular evidences, and redescribed on the basis of topotypic specimens. This species is distinguished from all other congeneric species by the following combination of characters: triangular-shaped rostral lobules without secondary rostral barbels; distal edge of dorsal-fin slightly concave; no longitudinal black stripe on the flank; a longer snout (length 52.6-64.5 % of HL); a more backwards-placed anus (the vent to anal distance 34.7-46.1% of the pelvic to anal distance); a slender caudal peduncle (depth 9.1-11.3 % of SL); a longer anal-fin base (length 7.5-9.5 % of SL); and a smaller gill opening with its upper extremity closer to the level of the lower margin of the orbit. The validity of V. intermedia is also confirmed by its significant cyt b gene sequence divergence with all sampled congeneric species and its monophyly recovered in the cyt b gene-based phylogenetic analysis.


Assuntos
Cyprinidae , Cipriniformes , Animais , China , Filogenia , Rios
3.
Zootaxa ; 4819(1): zootaxa.4819.1.9, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-33055676

RESUMO

A new species of Macrognathus of the M. aculeatus species group is described from the Kahayan River drainage in southern Borneo, Kalimantan Tengah, Indonesia. Macrognathus kris, new species, is distinguished from all Asian congeners in having the following unique combination of characters: rim of anterior nostril with two fimbriae and two fimbrules; 43-45 rostral tooth plates; 24-25 dorsal spines; 46-55 dorsal-fin rays; 51-59 anal-fin rays; 20-23 principal caudal-fin rays; 76-78 total vertebrae; body depth at anus 11.8-15.9% SL; color pattern consisting of light brown stripe on dorsum and 11-14 irregular pentagonal dark brown blotches on sides of body.


Assuntos
Peixes-Gato , Animais , Bornéu , Enguias , Indonésia , Rios
4.
Zootaxa ; 4819(1): zootaxa.4819.1.11, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-33055678

RESUMO

Betta nuluhon, new species, is described from a hill stream habitat in western Sabah. This species is allied to both B. chini and B. balunga, and differs from rest of its congeners in the B. akarensis group in having the following combination of characters: yellow iris when live; mature males with greenish-blue iridescence on opercle when live; mature fish with distinct transverse bars on caudal fin; slender body (body depth 22.1-25.2 % SL); belly area with faint reticulate pattern (scales posteriorly rimmed with black); absence of tiny black spots on anal fin; lateral scales 29-31 (mode 30); predorsal scales 20-21 (mode 20). Notes on a fresh series of B. chini are also provided.


Assuntos
Peixes , Animais , Cor , Ecossistema , Malásia , Masculino , Rios
5.
Zootaxa ; 4860(3): zootaxa.4860.3.3, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33055887

RESUMO

The New World genus Limnocoris Stål includes 73 described species, of which 13 are distributed in North America. A new species, Limnocoris rodriguesi Reynoso n. sp., from Mexico is described and illustrated, bringing the total number of species distributed in the country to eight. An updated checklist of the Mexican fauna of Limnocoris is presented and includes new state records for six species: Limnocoris hintoni La Rivers, L. inornatus Montandon, L. insularis Champion, L. lutzi La Rivers, L. pygmaeus La Rivers, and L. signoreti Montandon. Additionally, distribution maps for each of the species of Limnocoris in Mexico are presented.


Assuntos
Heterópteros , Distribuição Animal , Animais , México , Rios
6.
Zootaxa ; 4803(3): zootaxa.4803.3.3, 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-33056005

RESUMO

A parasitological survey of fishes from two tributaries (Veados and Paranapananema Rivers) of the Jurumirim Reservoir, Upper Paranapanema River, São Paulo State, Brazil, was carried out a during a sampling survey in 2011 and 2012. Several ectoparasitic copepods were found inside the nostrils of the freshwater anostomid fish, Schizodon intermedius Garavello Britski, 1990. The morphological analysis of the copepod specimens indicated that they represent two species of the ergasilid genus Gamispatulus Thatcher Boeger, 1984: Gamispatulus schizodontis Thatcher Boeger, 1984 (type species) and an undescribed species, Gamispatulus ferrilongus n. sp., which are described herein. The present specimens of G. schizodontis agree in several respects with its original description; however, some differences were found regarding the morphology of mouthparts and the ornamentation of legs and antennules. These differences were not sufficient to propose a new species for this genus. However, it could indicate the need for reassessment of the type material to have a more complete representation of this species. Gamispatulus ferrilongus n. sp. shares several similarities with its congener G. schizodontis but the new species can be readily distinguished from its congener in having a unique combination of diagnostic features including: a long rostral spine with tip extending up to half of cephalothorax, simple retrostylets (lacking adjacent spatulate processes), and dorsal surface of genital double-somite with 2 rounded processes (anterior and posterior) on both lateral margins. A host-parasite list for all vaigamid genera and species is included.


Assuntos
Caraciformes , Copépodes , Doenças dos Peixes , Animais , Rios
7.
Zootaxa ; 4803(3): zootaxa.4803.3.9, 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-33056011

RESUMO

Maharaja Barbs (Teleostei: Cyprinidae), endemic to the high-altitude streams of the northern Western Ghats are currently represented by a single species, Puntius sahyadriensis. Integrative taxonomic analysis of these fishes reveals them to form a distinct clade within the Cyprinidae, for which we propose the name Waikhomia gen. nov. Waikhomia differs from Puntius and other closely related genera by a combination of characters including: barbels absent; last unbranched dorsal-fin ray smooth, with highly segmented apex; total vertebrae 30 (17 abdominal and 13 caudal); post-epiphysial fontanelle absent, frontals elongated, parietals narrow; infraorbital 2-4 large, deep and wide, overlapping cheek and preopercle; opercle not overlapping the interopercle laterally; free uroneural 2 absent; lateral line complete, with 23-25 perforated scales; pelvic fins jet black with tip of fins white; and body coloration consisting of multiple (6-8) spots and blotches on side of body. We also describe a new species of Waikhomia from the west-flowing Kali river system in the northern part of the Western Ghats, India. The new species, Waikhomia hira is distinguished from W. sahyadriensis by a combination of characters including a distinct body coloration, consisting of 7-8 small, rhomboidal spots arranged across the lateral-line scale row; 23--25 perforated lateral line scales; 10 pre-dorsal scales and 2-3 sparsely spaced gill rakers on epibranchial 1. Further, W. hira differs from its sister taxon, W. sahyadriensis, by a raw genetic distance ranging from 4.3-4.9% in partial cytochrome oxidase subunit 1, and 7.0-8.2% in partial cytochrome b genes.


Assuntos
Cyprinidae , Nadadeiras de Animais , Animais , Citocromos b , Índia , Rios
8.
Zootaxa ; 4845(4): zootaxa.4845.4.5, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-33056756

RESUMO

The stoneflies and caddisflies of North Africa are still poorly known as vast areas of Algeria have yet to be investigated. A survey of the macroinvertebrates of the Seybouse River, northeast Algeria, was carried out from July 2014 to December 2016. Three species of stoneflies (Capnopsis schilleri, Capnioneura petitpierreae, and Tyrrhenoleuctra tangerina) and five taxa of caddisflies (Mesophylax aspersus, Hydropsyche maroccana, H. resmineda, H. artax/lobata, and H. gr. pellucidula) were identified. All taxa are new records to the Seybouse River and seven of them are new to northeastern Algeria. A multivariate analysis indicated that the Hydropsychidae exhibited a clear longitudinal gradient along the Seybouse River while Mesophylax aspersus seemed adapted to species-poor, intermittent streams. Further investigations of the stoneflies and caddisflies may inform conservation efforts and will prove useful to monitor the Seybouse River and similarly threatened North African rivers and streams.


Assuntos
Insetos , Argélia , Animais , Holometábolos , Rios
9.
Water Res ; 185: 116067, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33086458

RESUMO

Land-based micropollutants are the largest pollution source of the marine environment acting as the major large-scale chemical sink. Despite this, there are few comprehensive datasets for estimating micropollutant fluxes released to the sea from river mouths. Hence, their dynamics and drivers remain poorly understood. Here, we address this issue by continuous measurements throughout the Rhône River basin (∼100,000 km2) of 1) particulate micropollutant concentrations (persistant organic micropollutants: polychlorobiphenyls [PCBi] and polycyclic aromatic hydrocarbons [PAHs]; emerging compounds: glyphosate and aminomethylphosphonic acid [AMPA]; and trace metal elements [TME]), 2) suspended particulate matter [SPM], and 3) water discharge. From these data, we computed daily fluxes for a wide range of micropollutants (n = 29) over a long-term period (2008-2018). We argue that almost two-thirds of annual micropollutant fluxes are released to the Mediterranean Sea during three short-term periods over the year. The watershed hydro-climatic heterogeneity determines this dynamic by triggering seasonal floods. Unexpectedly, the large deficit of the inter-annual monthly micropollutant fluxes inputs (tributaries and the Upper Rhône River) compared to the output (Beaucaire station) claims for the presence of highly contaminated missing sources of micropollutants in the Rhône River watershed. Based on a SPM-flux-averaged micropollutant concentrations mass balance of the system and the estimates of the relative uncertainty of the missing sources concentration, we assessed their location within the Rhône River catchment. We assume that the potential missing sources of PAHs, PCBi and TME would be, respectively, the metropolitan areas, the alluvial margins of the Rhône River valley, and the unmonitored Cevenol tributaries.


Assuntos
Rios , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Mar Mediterrâneo , Poluentes Químicos da Água/análise
10.
Water Res ; 185: 116295, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33086459

RESUMO

The Three Gorges Dam (TGD) is the world's largest hydropower construction. It can significantly impact contaminant transport in the Yangtze River-East China Sea Continuum (YR-ECSC). In addition to evaluating the impact of the TGD on the deposition of contaminants in the reservoir, we also address their cycles in the river below the dam and in the coastal East China Sea. A comprehensive study of metal contaminant transport along the YR-ECSC has not been previously attempted. We quantified the fates of mercury (Hg), arsenic (As), lead (Pb), cadmium (Cd) and chromium (Cr) within the YR-ECSC, and the impacts of the TGD, by sampling water and suspended particles along the Yangtze River during spring, summer, fall, and winter and by modeling. We found that the Yangtze River transports substantial amounts of heavy metals into the coastal ocean. In 2016, riverine transport amounted to 48, 5900, 11,000, 230, and 15,000 megagrams (Mg) for Hg, As, Pb, Cd, and Cr, respectively, while other terrestrial contributions were negligible. Metal flux into the coastal ocean was primarily derived from the downstream portion of the river (84-97%), while metals transported from upstream were largely trapped in the Three Gorges Reservoir (TGR, 72%-96%). For example, 34 Mg of Hg accumulated in the TGR owing to river damming, large-scale soil erosion, and anthropogenic point source releases, while 21 Mg of Hg was depleted from the riverbed downstream owing to the altered river hydrology caused by the TGD. Overall the construction of TGD resulted in a 6.9% net decrease in the Hg burden of the East China Sea, compared to the pre-TGD period.


Assuntos
Monitoramento Ambiental , Metais Pesados , China , Metais Pesados/análise , Oceanos e Mares , Rios
11.
Zootaxa ; 4816(4): zootaxa.4816.4.3, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-33055684

RESUMO

The Gulf coastal drainages of central Mexico are a faunal transition zone between North and South America and harbor a unique assemblage of freshwater mussels (Bivalvia: Unionida). However, little information is available regarding the taxonomy, distribution, and evolutionary history of the Mexican mussel fauna due to limited sampling over the last 100 years. To address these knowledge gaps, we evaluated species-level diversity in the genus Popenaias Frierson, 1927, in Mexican Gulf coastal drainages as part of a larger effort to inform conservation efforts for members of this genus both in Mexico and the United States of America. Based on our analyses, we describe Popenaias berezai n. sp. from the Río Valles of the Río Pánuco basin, San Luis Potosí, Mexico. We also provide presumptive distributional range, phylogenetic structure, and molecular and morphological diagnoses of the new species and provide comments on the other species currently in Popenaias. Our findings highlight the high levels of endemism among freshwater mussels in Mexican Gulf coastal drainages and will help guide impending conservation actions for P. popeii, which is listed as "endangered" in the United States.


Assuntos
Bivalves , Unionidae , Animais , Água Doce , México , Filogenia , Rios
12.
Zootaxa ; 4780(2): zootaxa.4780.2.9, 2020 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-33055750

RESUMO

Museum specimens of a previously unknown species of the Anchitrematidae from a freshwater fish collected from the River Nile at Qena, Egypt were examined. This species is somewhat similar to species of Anchitrema, but was found to have a thick, continuous, shelf-like rim around the periphery of the ventral aspect of the distome, the lateral aspect of the forebody was composed of large internal patches of lightly vacuolated, somewhat glandular cells that formed pad-like structures (pelops-like structures), and it possessed a uterine seminal receptacle; characteristics that previously have not been found in any species in the family. Species currently assigned to Anchitrema or Mujibia (the only two genera in the family) are known only from reptiles and mammals and no species has previously been reported from a freshwater fish. We feel that these differences are sufficient enough to warrant the erection of Piscianchitrema n. gen. and amendation of the family. We support the synonymies of Anchitrema congolense with Anchitrema latum, and Anchitrema lucknowensis with Anchitrema indicum. The current status of species previously described in the family is discussed, and keys to the genera and species of Anchitrema are provided.


Assuntos
Rios , Trematódeos , Animais , Egito , Peixes , Água Doce
13.
Zootaxa ; 4858(1): zootaxa.4858.1.9, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-33056247

RESUMO

Serranochromis robustus robustus from Lake Malawi and Serranochromis robustus jallae from Zambia were compared using morphological data. We re-elevated S. robustus jallae to species based on the following. Serranochromis robustus generally has a longer lower jaw (50.7-59.6% HL) than S. jallae (49.2-52.7% HL). Serranochromis robustus is not as deep-bodied as S. jallae as evidenced by the distance between the posterior insertion of the dorsal fin and the posterior insertion of the anal fin (13.4-15.1% SL in S. robustus vs. 14.9-18.4% SL in S. jallae). Additionally, S. robustus has a narrower least caudal peduncle depth (10.9-12.8% SL) than S. jallae (11.3-14.2% SL); the least caudal peduncle depth of all S. robustus was less than 12.8% SL while, except for the smallest specimen of S. jallae (88.1 mm SL), the least caudal peduncle depth was greater than 13.2% SL. Adults in breeding color of Serranochromis robustus are blue/green laterally, while adults in breeding color of S. jallae are yellow/green laterally. The marginal bands on the dorsal and caudal fins of S. jallae are bright orange in specimens from the Okavango River system and creamy yellow in Upper Zambezi specimens. In S. robustus, there is a yellow marginal band on the dorsal fin.


Assuntos
Peixes-Gato , Ciclídeos , Animais , Rios
14.
Zootaxa ; 4853(3): zootaxa.4853.3.7, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-33056370

RESUMO

Boana freicanecae is a medium-sized hylid (males SVL= 37.3-42.2 mm) belonging to the B. pulchella group (Carnaval Peixoto 2004). This species is associated with streams in Atlantic montane forests (450-750 m elevation) located from the Pernambuco Biogeographic Sub-Region (Silva Casteleti 2003), in the states of Pernambuco and Alagoas, northeastern Brazil (Carnaval Peixoto 2004; Cardoso et al. 2006). Currently, B. freicanecae is classified as 'Data Deficient' according to the Brazilian Red List of Threatened species (ICMBio 2018) and many aspects of its natural history (e.g., advertisement call) are poorly known. Here we describe the advertisement call of this treefrog based on calls obtained from two populations.


Assuntos
Anuros , Vocalização Animal , Animais , Brasil , Florestas , Rios
15.
Zootaxa ; 4786(4): zootaxa.4786.4.1, 2020 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-33056458

RESUMO

The main goal of the present paper is to define the kozlovi-species group of the genus Trechus Clairville, 1806, one of the most species-rich groups of Chinese Trechus and to describe new species of this group from two neighboring areas in Sichuan Province. Description of species groups for Chinese Trechus is a way to get a more consistent view of the taxonomy of this extremely diverse genus. The kozlovi group includes many described species, which are widespread in Qinghai, Gansu and Sichuan provinces. In turn, the group can be split into several subgroups each embracing close allopatric relatives but much more material from various areas of China is required for such detailed classification. In the present work, we describe 9 new Trechus species belonging to this group, all collected in central and southern Sichuan, China: T. suopoensis sp. n. and T. gemaensis sp. n., both from the northern slopes of Mount Gema, E of Danba City, T. bianericus sp. n. and T. maoniu sp. n., both from the nortwestern slopes of the mountain massif located south of Bianer Village, WNW of Danba City, T. shangensis sp. n., T. mengensis sp. n., both from the upper valley of the small river located WSW of the village of Shangmeng, NW of Lixian City, T. cuspis sp. n. from the southern slope of Mount "5200" NW of Lixian City, three latter species from the left bank of the Zagunao River, T. qunlaishanicus sp. n. from the Qunlaishan mountains on the right bank of the Zagunao River and T. chiguguanensis sp.n. from the Chiguguan Pass.


Assuntos
Besouros , Animais , Rios
16.
Environ Monit Assess ; 192(11): 721, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33089438

RESUMO

For most rivers in sub-Saharan Africa, information about pollution indices related to sediments is sparse. Sedimentological research of rivers that empty into Lake Victoria is highly patchy and wide apart. The present study determined the levels and associated risk of As, Cd, Cr, Hg, and Pb in sediments collected from four different sites along the Mara River that empties into Lake Victoria in Tanzania. Samples were collected in the dry and rainy months in 2019. Pollution indices, namely geo-accumulation index (Igeo), enrichment factor (EF), contamination factor (CF), modified contamination degree (mCd), pollution load index (PLI), potential ecological risk factor (Eri), and potential ecological risk index (RI) were used to evaluate the influence of heavy metal contamination in sediments. Dry month mean concentrations, in milligram per kilogram, of heavy metals were as follows: As (11.04 ± 0.13), Cr (1.02 ± 0.29), Cd (0.43 ± 0.05), and Hg (0.01) in the dry month. Respective sediment heavy metal concentrations for the rainy month were 22.22 ± 0.05 mg As/kg, 3.84 ± 0.34 mg Pb/kg, 1.53 ± 0.15 mg Cd/kg, 1.43 mg Cr/kg, and 0.03 mg Hg/kg. Generally, the risk indices showed high values in the rainy month and low values in the dry month, especially for As and Cd-an indication of anthropogenic influence. Correlation coefficient analysis for Pb and Cd showed a strong positive correlation (r = 0.99, p < 0.01)-this may suggest a similar source or similar transport behavior. Special attention needs to be paid with regard to rainy season As and Cd enrichment in the study area.


Assuntos
Rios , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Medição de Risco , Tanzânia , Poluentes Químicos da Água/análise
17.
Environ Monit Assess ; 192(11): 713, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33074388

RESUMO

The quality of surface water could be influenced by both anthropogenic and natural factors. This study was designed to determine the impact of informal settlement and wastewater treatment plants on helminth egg contamination of urban rivers and the risks associated with everyday use. We also ascertained the accumulation of these eggs in the river sediments. The study was carried out in two rivers in the eThekwini Municipality of South Africa. Grab samples were taken at different points over a 10-month period. Ascaris spp., hookworm, Toxocara spp., Trichuris spp. and Taenia spp. were the helminth eggs detected in both the water column and sediments, with mean Ascaris spp. eggs of 0-6.3 (± 5.1)/L in the water and 0-6.8 (± 5.2)/kg in sediment samples. The helminth egg concentrations showed seasonal variation, probably due to changes in infection levels of the populations or natural factors, such as rainfall. The informal settlements had a greater impact than treated wastewater. For every 10,000 recreational users of the rivers 19 to 58 may be infected under undisturbed conditions, increasing to 29-88 individuals when the riverbed is disturbed. The risk from agricultural use of the rivers was above the tolerable risk values applicable for wastewater reuse, recommended by the World Health Organization. This calls for a re-evaluation of the policies governing surface water quality assessment, where the inclusion of helminth eggs and sediment monitoring will be critical.


Assuntos
Helmintos , Águas Residuárias , Animais , Monitoramento Ambiental , Humanos , Rios , África do Sul
18.
Environ Monit Assess ; 192(11): 700, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33047214

RESUMO

To investigate the possible impact of the traffic flow of mountainous roads and the construction and operation of a long tunnel on the water quality of a reservoir, this study conducts statistical analysis on water quality, meteorological, and traffic data of the Feitsui Reservoir and its upstream tributaries over the last three decades. Results from statistical regression analysis indicate that in the upstream area where the traffic flow is low, water quality varies insignificantly with rainfall and traffic flow, providing as a background reference of natural environment. Water quality near a conventional highway on which many vehicles travel through the catchment area is significantly affected by both rainfall and traffic flow since the drainage system of a conventional highway sends its gathered water into adjacent rivers. Not only does traffic flow generate contaminants, but also the construction of the Hsuehshan Tunnel of the No. 5 Expressway, Taiwan, in the catchment area of the Feitsui Reservoir generates pollution. Drainage, silt settling and retarding basin, and wastewater treatment facilities near the construction site mitigate the impact of tunnel construction and traffic flow on the environment. The No. 5 Expressway makes good use of viaduct and tunnel structures, collecting water from pavements within the catchment area into sewage facilities, filtering it, and then emitting it outside the catchment area, forming a closed system over the Feitsui Reservoir. The Expressway now shortens travel time from two hours to 40 min and accommodates 7-13 times previous traffic flows, insignificant influencing water quality in the upstream tributaries of the reservoir, demonstrating the effectiveness of its environmental protection measures.


Assuntos
Monitoramento Ambiental , Qualidade da Água , Rios , Taiwan , Águas Residuárias
19.
Zootaxa ; 4810(3): zootaxa.4810.3.4, 2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-33055732

RESUMO

Helminthological examination of viscera of six freshwater fish species, collected from Misión la Paz, Pilcomayo River, Province of Salta, Argentina, revealed the presence of five species of parasitic nematodes belonging to the Camallanidae, Cystidicolidae, Cucullanidae and Anisakidae  The material also contained one unknown species, Procamallanus (Spirocamallanus) tomsici sp. nov. collected from Pimelodus albicans, Pygocentrus nattereri and Hoplias misionera. This species is distinguished from its congeners all over de world by possessing six pores distinctly surrounding the mouth aperture, a buccal capsule with 3-4 spiral thickenings complete, females possessing a lateral cuticular ornamentation along the body, and two pairs of preanal and three pairs of postanal papillae in males. The findings represent new hosts and geographical records.


Assuntos
Peixes-Gato , Nematoides , Animais , Argentina , Feminino , Água Doce , Masculino , Rios
20.
Zootaxa ; 4790(2): zootaxa.4790.2.8, 2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-33055845

RESUMO

Rhodeus flaviventris, a new species, is described from the Le-An River, a tributary flowing into Poyang Lake in the Yangtze River basin, in Jiangxi Province, China. It is distinguished from all congeners by the combination of characters: branched dorsal-fin rays 9 (9-10); branched anal-fin rays 9 (9-10); longest simple rays of dorsal and anal fins thick and stiff; longitudinal scale series 33-34; transverse scale series 11 (10-12); pored scales 4-7; vertebrae 32-34; spindle-shaped eggs with major axis of 3.1-3.7 mm; color pattern of nuptial males (iris yellowish, belly yellow, central part of caudal fin orange, dorsal and anal fins with reddish-orange stripe).


Assuntos
Cyprinidae , Animais , China , Cor , Masculino , Rios
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