Thematic Section: Reservoirs Ecology Acta Limnologica Brasiliensia, 2018, vol. 30, e306 https://doi.org/10.1590/S2179-975X13717 ISSN 2179-975X on-line version This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Is it possible to evaluate the ecological status of a reservoir using the phytoplankton community? É possível avaliar o Potencial Ecológico de um reservatório usando a comunidade fitoplanctônica? Aline Martins Vicentin1*, Eduardo Henrique Costa Rodrigues1, Viviane Moschini-Carlos1 and Marcelo Luiz Martins Pompêo2 1 Universidade Estadual Paulista – UNESP, Campus Experimental de Sorocaba, Av. Três de Março, 511, Iperó, CEP 18087-180, Sorocaba, SP, Brasil 2 Departamento de Ecologia, Instituto de Biociências – IB, Universidade de São Paulo – USP, Rua do Matão, 321, Travessa 14, CEP 05508-900, São Paulo, SP, Brasil *e-mail: line_vicentin@hotmail.com Cite as: Vicentin, A.M. et al. Is it possible to evaluate the ecological status of a reservoir using the phytoplankton community? Acta Limnologica Brasiliensia, 2018, vol. 30, e306 Abstract: Aim: The present study aims to evaluate the ecological status of the Broa reservoir through the application of the ecological index Evenness E2 on phytoplankton. Methods: Phytoplankton samples from surface were obtained during the dry period (June/2015) in 9 points (P1 to P9), along a longitudinal transect in the reservoir. The qualitative analysis was performed using binocular optical microscope, and the quantitative analysis was performed using the sedimentation chamber method and inverted microscope analysis. The Uniformity Index was calculated on density and richness data. The reference values used in this study were set according to the literature covering 5 classifications (High, Good, Moderate, Low and Bad) for the water quality from Evenness E2 index for phytoplankton, being 1 the maximum value. Results: The values observed ranged from 0.1142 in P1 to 0.1468 in P3, being both classified as “Bad”, since values were less than 0.21. Conclusions: The result reinforces the sanitary problem of the reservoir, the occurrence of consecutive algae blooms because the amount of nutrients in the region. A massive occurrence of Cyanobacteria was observed, with emphasis on the species Aphanizomenon gracile, which may be related to the adaptive advantages that this class presents on the community in eutrophic environments. Activities in the basin can contribute effectively to the eutrophication process of the reservoir, such as agriculture, sand mining and livestock. The water quality is compromised due to the dense presence of potentially toxic species, reflects of the eutrophication process, pointing commitments for the multiple uses of the reservoir, as well as human and ecosystem health. These processes could be corroborated by the application of the index and indication of poor water quality. Keywords: phytoplankton; Ecological Uniformity Index; Evenness Index E2; water quality; eutrophication. Resumo: Objetivo: O presente trabalho objetiva avaliar o potencial ecológico do reservatório Broa através da aplicação do índice ecológico Evenness E2 no fitoplâncton. Métodos: Amostras fitoplanctônicas de superfície foram obtidas no período seco (Jun./2015) em nove pontos (P1 ao P9) ao longo do eixo longitudinal do reservatório. A análise qualitativa foi feita usando microscópio óptico binocular e a análise quantitativa foi realizada pelo método de câmaras de sedimentação e análise em microscópio invertido. O Índice de Uniformidade foi calculado a partir dos dados de 2 Vicentin, A.M. et al. Acta Limnologica Brasiliensia, 2018, vol. 30, e306 resulting in modifications that directly affect the hydro-sedimentological dynamics between river-dam (Coelho, 2008). In response to these changing conditions, the environment becomes conducive to colonization by species that are tolerant to disturbances, and that may establish a relationship of dominance with other species, making that dams act as modulators of taxa richness and abundance (Smith et al., 2017). The maintenance of the water resource quality depends on the dynamics of the aquatic ecosystem and on the organisms that compose it, which are able to act in the nutrient cycling, gas exchange, sediment stabilization, composition and structure of the community (Lewis, 1995). This approach requires the interpretation of biotic and abiotic data to understand the existing ecological processes and, consequently, the functioning of the ecosystem and the concept of biodiversity (Lanari & Coutinho, 2010). According to the same authors, concepts related to the ecology of communities and ecosystems must be worked in an integrated way to derive the effects of species diversity on the representative parameters of the environment. Thus, biodiversity responds to the environmental condition generated by the ecosystem and determined by its ecological functioning. The phytoplankton community is a part of the aquatic ecosystems biota and contributes actively to primary productivity and to biogeochemical cycles (Miller  et  al., 2012). Phytoplankton can present spatial and temporal variations, both qualitative and quantitative. These characteristics are influenced by other conditions of the system: thermal stratification, water circulation, season of the year, and others (Esteves, 2011). Due to the environmental factors and individual advantages 1. Introduction The construction of multiple-use water reservoirs contributes significantly to the regularity of water supply, and to the development and maintenance of various economic activities (e. g. industrial, agricultural, aquiculture, navigation). However, these environments are facing different impacts involving water quality and consequently the ecological balance of these ecosystems. The main impacts affecting the water quality of the reservoirs are due to the discharge of domestic and industrial effluents, such as the surface runoff of agricultural and urban areas, which also contributes to the pollutants disposal to the interior of these environments (Cunha  et  al., 2013). Currently, aquatic and terrestrial ecosystems have been greatly modified by anthropic activities, direct or indirectly, leading to changes in ecosystem dynamics, including water quality, and consequently, the biological communities, which may compromise the multiple uses of the water body (Lewis, 1995; Sant’anna et al., 2008; Tundisi et al., 2015; Pompêo, 2017). Reservoirs are considered transition ecosystems between lotic and lentic environments, depending on the characteristics of the hydrographic basin where they are inserted which presents specific operating mechanisms (Pompêo, 2017). The impact on the environment from the rupture of the hydrological continuum changes the dynamics in its totality. These changes occur because the system components are altered, including the flow regime, channel size, substrate present and biotic diversity (Bunn & Arthington, 2002). The damming of a river means an interruption of a transportation open system by a more closed and accumulation system (Junk & Mello, 1990), densidade e riqueza. Os valores de referência utilizados foram estabelecidos de acordo com a literatura abrangendo cinco classificações (Alto, Bom, Moderado, Baixo e Ruim) do índice Evenness E2 para fitoplâncton, sendo 1 valor máximo indicando as classificações de qualidade da água. Resultados: Os valores observados variaram entre 0,1142 em P1 a 0,1468 em P3, sendo ambos classificados como “Ruim”, visto valores inferiores a 0,21. Conclusões: O resultado reforça a problemática sanitária do reservatório, pela ocorrência de consecutivas florações algais (“blooms”), pelo aporte e concentração de nutrientes na região. Ocorrência massiva de Cianobactérias foi observada, com ênfase para a espécie Aphanizomenon gracile, podendo estar relacionada às vantagens adaptativas que esta classe apresenta sobre a comunidade em ambientes eutrofizados. As atividades na bacia contribuem efetivamente para o processo de eutrofização do reservatório, como atividades agrícolas, de mineração de areia e pecuária. A qualidade da água está comprometida devido à densa presença de espécies potencialmente tóxicas, refletindo no processo de eutrofização, apontando comprometimento aos múltiplos usos do reservatório, além da saúde humana e ecossistêmica. Esses processos podem ser corroborados pela aplicação do índice e indicação de má qualidade da água. Palavras-chave: fitoplâncton; Índice Ecológico de Uniformidade; Índice Evenness E2; qualidade da água; eutrofização. 3 Is it possible to evaluate… Acta Limnologica Brasiliensia, 2018, vol. 30, e306 of each family, or even of an organism of the community, phytoplankton can have its structure and composition rapidly changed under human effects due to the sensitivity of organisms, since planktons are profoundly sensitive to natural change they are best markers of water quality and particularly lake conditions (Parmar et al., 2016), by being well documented in the literature the use of these organisms, with greater importance given to phytoplankton, in studies of biomonitoring (using different methodologies) in aquatic environments, mainly reservoirs (Yuan et al., 2018; Santana et al., 2017; Machado et al., 2016; Hu et al., 2016; Silva & Costa, 2015; Padisák et al., 2006). The biodiversity of the phytoplankton community is influenced and it has the capacity to influence the ecological processes of the ecosystem based on the functional characteristics of each species that make up the community (Lanari & Coutinho, 2010). This biodiversity is responsible for the intense blooms occurrence and the eutrophication process of water bodies, which may worsen the water quality and the risks associated with its composition, considering the presence of Cyanobacteria. Currently, the alterations in the reservoirs have become more common and intense, generated or accelerated by anthropic activities, assuring a greater number of water pollution forms (Straskraba & Tundisi, 2013). It becomes challenging because the degradation speed is higher than the evaluation of the damage impact, complicating the decision-making process for water recovery (Miller et al., 2017). Although the Broa reservoir is intended for recreation and research purposes, it is inserted in the Tietê-Jacaré hydrographic basin that has potentially polluting activities, such as agriculture, sand mining, livestock, and other point and diffuse sources (Periotto & Tundisi, 2013). The activities includes the disposal of untreated residential effluent, deforestation, sand mining, tourism, intensive sport fishing (Cervi  et  al., 2016) and agricultural activities, also with areas under legal protection (Tundisi & Tundisi, 2016). There are also reforestation initiatives in the region, besides the natural maintenance from the vegetation cover, highlighting the mosaic vegetation acting as a buffer zone (Tundisi & Tundisi, 2016). Despite these notes, the authors Tundisi and Matsumura-Tundisi (2014) point out that the reservoir maintains its main characteristics. This environment is considered one of the most studied reservoirs in Limnology, for at least 40 years of information and data applied to several areas of knowledge, contributing to the region development related to social, economic and environmental issues (Periotto & Tundisi, 2013). The phytoplankton community was commonly characterized by the dominance of diatoms and chlorophytes (Tundisi & Matsumura-Tundisi, 2014), except for the year 2014 that presented a pioneering bloom of cyanobacteria (Tundisi et al., 2015). Emphasizing the importance of the study of the phytoplankton community, especially of the Cyanobacteria, due to their capacity to produce toxins (Cyanotoxins) with adverse health effects. Knowing that the phytoplankton composition of the reservoir depends on the environmental variables and their interactions, and that the eutrophication process can alter the occurrence and distribution of phytoplankton (Esteves, 2011), the application of Evenness E2 was performed understand these changes. T h e B r o a r e s e r v o i r i s c o n s i d e r e d oligo-mesotrophic (Calijuri & Tundisi, 1990; Tundisi & Matsumura-Tundisi, 2014; Tundisi et al., 2015), presenting oscillations in their trophic condition according to the period and specific site of sampling, but remaining between the bands of oligotrophic and mesotrophic (Tundisi, 1977; Luzia, 2009; Tundisi et al., 2015), with a tendency of trophic enrichment coming from the tributaries (Luzia, 2009). Considering the trophic history of the reservoir, the hypothesis is based on the dominance of Cyanobacteria along the longitudinal axis, resulting in low values for the Evenness E2 index. This index of equitability aims to express the way in which the amount of individuals is distributed among the different species, it will be used as an alternative to evaluate the water quality of the reservoir and to verify if it is corroborated by other obtained information. 2. Materials and Methods 2.1. Study area Carlos Botelho Hydroelectric Power Station, also known as the Broa or Lobo Reservoir, is an artificial water body located between the cities of Itirapina and Brotas, inserted in the Tietê-Jacaré hydrographic basin in the State of São Paulo, Brazil (between 49°32’-47°30’ longitude and 21°37’-22°51’ latitude). The reservoir was built in 1936 with the purpose of producing electric energy, with an surface area of 6 km2, maximum length of 8 km, average width of 0.9 km and average depth of 3 m (Cervi  et  al., 2016), considered shallow, 4 Vicentin, A.M. et al. Acta Limnologica Brasiliensia, 2018, vol. 30, e306 polymictic and presenting a retention time of less than 25 days (Tundisi & Tundisi, 2016). According to the Decree nº. 10.755/77, the Carlos Botelho reservoir is classified as class 2 (São Paulo, 1977), and is destined, according to CONAMA resolution no. 20/86, to water domestic supply (considering the conventional water treatment), to aquatic communities protection, to recreation of primary contact, to vegetable and fruit plant irrigation, to natural and intensive plantations for human consumption (Brasil, 1986). As well as the purposes that were pre-determined by law, the regulations regarding limnological variables are also clearly established in the CONAMA Resolution 357/05 (Brasil, 2005). 2.2. Sampling and analysis of samples The single collecting of five-liter sampling consisted of water from the surface during the dry season (June/2015), at nine points distributed along the longitudinal axis (P1 to P9). These points comprised the lotic (P1, P2 and P3), central (P4, P5 and P6) and lentic (P7, P8 and P9) region of the reservoir (Thornton et al., 1990) (Figure 1), and each one was meant for the physicochemical and biological analyzes. The collected material was stored and conditioned in thermal bags and sent to the Limnology Laboratory, University of São Paulo (USP). The GPS coordinates (UTM, Datum WGS 84), depth (m), water surface temperature (°C), dissolved oxygen (mg.L-1), electrical conductivity (µS.cm-1), pH and Secchi depth (m) of the water were measured in the field using the YSI 556 MPS multi-parameter probe (HORIBA). The euphotic zone was measured as 2.7 times the depth of Secchi (Cole, 1994). The physicochemical analyzes were performed in the laboratory, following a specific methodology: chlorophyll-a (Chlor. a) (Lorenzen, 1967), nitrite (NO2 -) and nitrate (NO3 -) (Mackereth  et  al., 1978), ammonium Figure 1. Representation of the sampling points (P1 to P9) in the Broa reservoir and its respective tributaries, located in the State of São Paulo, Brazil. The different shades of gray highlighting the following sets of sample points (P1 – P3; P4 – P6; and P7 – P9) indicate the theoretical zones of river, center and dam, respectively. From: Adapted from Tundisi et al. (2004). 5 Is it possible to evaluate… Acta Limnologica Brasiliensia, 2018, vol. 30, e306 (NH4 +) (Koroleff, 1976), total nitrogen (T.N.), total phosphorus (T.P.) (Valderrama, 1981) and Orthophosphate (P-ortho) (Strickland & Parsons, 1960). For the phytoplankton sampling, mesh net with 20 µm was used in horizontal trawls at the water surface (one point per zone), and fixed with formaldehyde (4%); and by direct collection in the photic zone, fixed with 1% acetic lugol, the material was subsequently identified according to current works (Sant’anna et al., 2006; Biolo et al., 2008; Dellamano-Oliveira  et  al., 2008; Menezes  et  al., 2011; Nogueira et al., 2011; Ramos et al., 2012; Rosini  et  al., 2013; Aquino  et  al., 2014; Souza & Felisberto, 2014; Alves-da-Silva & Klein, 2015), and counted according to Utermöhl (1958) methodology, in sedimentation chambers (Lund et al., 1958) and inverted microscope Zeiss (Axiovert 40C). The density of the phytoplankton community (cel.L-1) was obtained from the count of the organisms in relation to the area of the used sample container (INAG, I.P., 2009), following the Equation 1. = A*dN X* a*v (1) Where, N: number of units per volume in the sample (units.mL-1), X: average number of units per square or transept (or total number of units in the chamber), A: chamber area, v: sample volume sedimented in chamber, a: area of the counting field (grid, transept or chamber), and d: dilution factor or sample concentration, if applicable. For colonies and filaments, it was necessary to estimate the average number of cells present and to multiply by the number of times they occur. 2.3. Data analysis The application of Principal Component Analysis (PCA) was performed by using correlation matrix to verify the environmental variability in Carlos Botelho reservoir. The use of row color/symbols, convex hulls and filled regions in order to improve the visualization of the areas formed by the polygons, and associated with the limnological variables, using the PAST program (3.13) (Hammer, 2001). The Trophic State Index (TSI) proposed by Lamparelli (2004) was applied, and it was determined from the weighting between values of chlorophyll-a and total phosphorus, and classified as Ultra-oligotrophic, Oligotrophic, Mesotrophic, Eutrophic, Super-eutrophic and Hyper-eutrophic. The reference values to determinate the trophic limits are shown in Table 1. Data analysis consisted in application of Evenness E2 uniformity index, proposed by Sheldon (1969). Using software PAST (3.13) (Hammer, 2001), the following equation (Equation 2) is applied to the phytoplankton and the index values are generated. ( ) = ′exp H E2 S (2) The reference values used for the water quality classification from the application of the index to phytoplankton were proposed by Spatharis & Tsirtsis (2010), establishing five (5) classifications (High, Good, Moderate, Low and Bad), where 1 is the maximum value (Table 2). 3. Results 3.1. Phytoplankton characterization The qualitative analysis of the phytoplankton community from Broa Reservoir was represented by 92 species, distributed in 52 genera and 10 taxonomic classes. The percentage distribution of the community classes is represented in Figure  2. The following taxonomic classes and their respective percentage distribution were identified: Chlorophyceae (38%), Cyanophyceae (28%), Trebouxiophyceae (11%), Bacillariophyceae (8%), Coscinodiscophyceae (5%), Cryptophyceae (3%), Dinophyceae (3%), Euglenophyceae (2%), Xanthophyceae (1%) e Zygnematophyceae (1%) (Figure 2). The Chlorophyceae class presented the greatest richness, grouping 35 species in 13 genera, Table 1. Trophic state classification for reservoirs (modified by Pompêo, 2017). Category (Trophic State) Range P-Total – P (mg.m-3) Chlor. a (mg.m-3) Ultraoligotrophic TSI ≤ 47 P ≤ 8 CL ≤ 1.17 Oligotrophic 47 < TSI ≤ 52 8 < P ≤ 19 1.17 < CL ≤ 3.24 Mesotrophic 52 < TSI ≤ 59 19 < P ≤ 52 3.24 < CL ≤ 11.03 Eutrophic 59 < TSI ≤ 63 52 < P ≤ 120 11.03 < CL ≤30.55 Supereutrophic 63 < TSI ≤ 67 120 < P ≤ 233 30.55 < CL ≤ 69.05 Hypereutrophic TSI > 67 233 < P 69.05 < CL 6 Vicentin, A.M. et al. Acta Limnologica Brasiliensia, 2018, vol. 30, e306 of which the genus Desmodesmus sp. included 8 different species. The values of the phytoplankton community density are shown in Figure  3, distributed by sample point and taxonomic class, ranging from 32.2. 107 cel.L-1 in P8 to 67.6. 107 cel.L-1 in P4, following the decreasing order: Cyanophyceae, C h l o ro p h yc e a e , C o s c i n o d i s c o p h yc e a e , Tr e b o u x i o p h yc e a e , Ba c i l l a r i o p h yc e a e , Cryptophyceae, Dinophyceae, Xantophyceae, Euglenophyceae and Zygnematophyceae. The cell density of Cyanobacteria corresponded to 43.6. 108 cel.L-1 in relation to 8.4. 103 cel.L-1 of Zygnematophyceae class. The Cyanophyceae class was more representative due to the large number of cells of mature colonies of Microcystis sp. and Aphanocapsa sp. by sample, as well as of filamentous species of Dolichospermum sp. and Aphanizomenon gracile. 3.2. Limnological characterization The results from the field and research laboratory analyzes of the following variables (Var.): depth, water surface temperature (T.), dissolved oxygen (D.O.), electrical conductivity (E.C.), hydrogenation potential (pH), Secchi depth (S.D.), chlorophyll-a (Chlor. α), nitrite (N02 -), nitrate (NO3 -), ammonium (NH4 +), total nitrogen (T.N.), total phosphorus (T.P.) and Orthophosphate (P-ortho) are shown in Table 3, with their units, mean values, minimum (min.) and maximum (max.) values. The average depth observed in Carlos Botelho reservoir was slightly high (6.7 m), with lower depth in P1 (3.2 m) and gradually increasing towards the dam (13.0 m). The surface temperature of the water had thermal amplitude lower than 3ºC. The concentration of dissolved oxygen showed low values in all the sampled points, except for the peak in P1 (8.37 mg.L-1). The values of pH, electrical conductivity and Secchi depth were quite homogeneous along the longitudinal axis observed in the water body, presenting small amplitude of variation, with average values of 8.59, 0.02 mS.cm-1 and 0.61 m, respectively. The  inorganic nutrients analysis indicated low values of nitrate (12.95 µg.L-1) and total phosphorus (26.56  µg.L-1) in the environment. The nitrite, ammonium and orthophosphate analyzes indicated Table 2. Reference values of Evenness E2 index to phytoplankton classifying the water quality (Spatharis & Tsirtsis, 2010). Water quality classification Evenness E2 High 0.96-0.77 Good 0.77-0.46 Moderate 0.46-0.30 Low 0.30-0.21 Bad 0.21-0.09 Table 3. Data from physicochemical analyzes obtained in the field and posterior laboratory analysis. Var. Units Mean Min. Max. Depth m 6.71 3.20 13.00 T. °C 22.68 21.79 24.72 D.O. mg.L-1 4.34 3.36 8.37 pH - 8.59 8.09 9.07 E.C. mS.cm-1 0.020 0.017 0.032 S.D. m 0.61 0.48 0.78 NO3 - μg.L-1 12.95 10.46 18.20 NO2 - μg.L-1
20. Since the community included 92 identified and counted species, the application result was considered valid. Borges  et  al. (2008) observed a scenario closed to the present work in a study of daily variation in eutrophic environment, highlighting the low equitability with occurrence and dominance of Cyanobacteria in one arm of the Rosana reservoir (Ribeirão do Corvo, Paraná, Brazil). From a comparative analysis between the TSI and Evenness E2, both were applied to measure the water quality status from different approaches. The first index relates the availability of nutrients in relation to algal growth, correlating an 11 Is it possible to evaluate… Acta Limnologica Brasiliensia, 2018, vol. 30, e306 environmental condition variable corresponding to the total phosphorus concentration and a biological response variable (Chlorophyll-a). The   trophic levels are associated with the intensity of the eutrophication process, so it can be considered a more robust index to evaluate the ecological potential of a reservoir. However, considering that Evenness E2 is an index of equitability applicable to the phytoplankton community, it is a more accurate biological indicator than a metric of abundance obtained from the quantification of photosynthetic pigments, although satisfactory. This index, individually analyzed, is able to derive a biological response and to identify ecological imbalances, but it is not robust in integrated environmental approaches, since it does not accompany any physical-chemical variables in its composition, being necessary the accomplishment of complementary analyzes. Thus, it is possible to apply the Evenness E2 index in the evaluation of the ecological potential combined with complementary environmental analyzes, so that can robustly measure water quality. For both indexes, the knowledge of the composition of the community enriches the results, since different taxa imply different measures of flowering containment and modulate the risk with which the water quality is associated. In this study, the hypothesis of dominance of Cyanobacteria along the longitudinal axis was corroborated from indicative of the trophic degree associated with the TSI and low values for the Evenness E2 index. 5. Conclusion The results are associated to the sanitary problem of the reservoir, giving margin to the occurrence of blooms and consequently to the presence of Cyanobacteria. Despite the diffuse sources of phosphorus and nitrogen, Cyanobacteria can develop more efficiently in environments with a higher trophic level, as observed by the massive presence of Aphanizomenon gracile in the eutrophic environment, with high concentrations of nitrogen, chlorophyll-a, Cyanobacteria density and low concentrations of dissolved oxygen. The control of the effluents from the basin activities and other nutrient sources, mainly nitrogen and phosphorus, is determinant in the control of the eutrophication process. This process prioritizes the phosphorus concentration, since nitrogen sources can be difficult to identify, because it includes the fixation of atmospheric nitrogen by some algae. The use of biological communities and application of Evenness E2 proved to be satisfactory when compared to limnological analysis, since it made the environmental analysis more accomplished and it also assisted in better understanding of the other results, contributing to more robust information for the decision maker. The application of the Evenness E2 index using the phytoplankton community indicated that the water quality of the Broa reservoir is compromised by the presence of potentially toxic species. This condition may influence the multiple uses of the reservoir and bring risks to human and ecosystem health. Complementary studies should be performed to determine the toxicity that the ecosystem is subject. Acknowledgements The authors are grateful to CAPES, to FAPESP (Processes 2014/22581-8; 2016/17266-1), to the research group of the Limnology Laboratory, to the Institute of Biosciences (IB) of the University of São Paulo (USP), to the Environmental Sciences Program (PROPG), to the Institute of Science and Technology of the São Paulo State University “Júlio de Mesquita Filho” (UNESP), for direct and indirect collaboration in the present work. The study is part of the Dissertation Project “Assessment of the spatial heterogeneity of the Carlos Botelho Reservoir (Lobo/Broa), with emphasis on the phytoplankton community”. References ALVES-DA-SILVA, S .M. and KLEIN, I .C. Euglenophyceae na Área de Proteção Ambiental do Rio Ibirapuitã, sudoeste do Estado do Rio Grande do Sul, Brasil. 1. Cryptoglena Marin & Melkonian emend. Kosmala & Zakrýs, Monomorphina (Ehrenberg) Mereschkowsky emend. 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