A review of Neotropical species in Thienemanniella Kieffer (Diptera, Chironomidae).

Three species previously described from the neotropical region are revised and four new species are described: Thienemanniella biobio sp. n. and T. manihuales sp. n. as males and pupae from Chile, T. sancticaroli sp. n. and T ubatuba sp. n. as males, females and immature stages from Brazil. The new Thienemanniella spreta species group is delimited consisting of T. spreta (Roback) sensu Sublette & Sasa, T. sanctivincenta Saether, T. liae Paggi, T. sancticaroli sp. n. and T. ubatuba sp. n. Keys to the known Neotropical males, pupae and larvae are presented.

Tapajos cristinae gen. n., sp. n. (Diptera: Chironomidae: Chironominae) from the Neotropical region.

A new genus of non-biting midges, Tapajos gen. n., is erected for T cristinae sp. n. from the Neotropical region, and placed in the subfamily Chironominae, tribe Chironomini. Adult males are characterized by the combination of bare eyes; antenna with 11 flagellomeres; antepronotal lobes fused medially; fore tibia with inner scale broad and rounded; superior volsella with a long sickle shaped, bare part arising from the distal lateral corner of a globose, densely trichiose base; inferior volsella sub-cylindrical, surpassing the anal point, distally setose and slightly expanded.

Thalassomya gutae sp. n., a new marine chironomid (Diptera: Chironomidae: Telmatogetoninae) from the Brazilian coast.

One new species of Thalassomya Schiner, 1856 (Diptera: Chironomidae: Telmatogetoninae), T. gutae sp. n. is described and figured as male, pupa and larva. The specimen was collected in the marine zone between tidemarks, in southeastern Brazilian coast and is the first species of this genus recorded to Brazil.

Evaluating the use of predatory insects as bioindicators of metals contamination due to sugarcane cultivation in neotropical streams.

Streams located in areas of sugarcane cultivation receive high concentrations of metal ions from soils of the adjacent areas causing accumulation of metals in the aquatic sediment. This impact results in environmental problems and leads to bioaccumulation of metal ions in aquatic organisms. In the present study, metal concentrations in different predatory insects were studied in streams near sugarcane cultivation and compared to reference sites. Possible utilisation of predatory insects as bioindicators of metal contamination due to sugarcane cultivation from 13 neotropical streams was evaluated. Ion concentrations of Al, Cd, Cr, Cu, Zn, Fe, and Mn in adult Belostomatidae (Hemiptera) and in larvae of Libellulidae (Odonata) were analysed. Nine streams are located in areas with sugarcane cultivation, without riparian vegetation (classified as impacted area) and four streams were located in forested areas (reference sites). Metal concentrations in insects were higher near sugarcane cultivations than in control sites. Cluster analysis, complemented by an ANOSIM test, clearly showed that these insect groups are good potential bioindicators of metal contamination in streams located in areas with sugarcane cultivation and can be used in monitoring programmes. We also conclude that Libellulidae appeared to accumulate higher concentrations of metals than Belostomatidae.

New Polypedilum Kieffer (Diptera: Chironomidae) from mountains of the Atlantic Forest, Brazil.

Five new species of Polypedilum from mountains of the Atlantic Forest, Southeastern Brazil, are described and illustrated as adult male. Two new species belong to the subgenus Polypedilum s. str.: Polypedilum (Polypedilum) caete sp. n. and P. (P.) aymbere sp. n. and three new species belong to the subgenus Tripodura: P. (Tripodura) yvatekaty sp. n., P. (T.) goiocoio sp. n. and P. (T.) ybytyra sp. n.

Chironomus rishii sp. n., an enigmatic non-biting midge (Diptera: Chironomidae: Chironominae) from Neotropical region.

A new species of Chironomus Meigen, C. rishii (Diptera: Chironomidae: Chironominae) from Brazil, is described and figured as adults male and female, pupa and larva. Adults of C. rishii sp. n. can be recognized by the prominent scutal tubercle and the hypopygium with narrow, elongated and strongly hooked superior volsella. Pupae of this new species are indistinguishable from most of the described Neotropical species, while larvae may be separated by the mentum with deeply incised trifid median tooth and 7 pairs of lateral teeth and the absence of lateral and ventral tubules. This last feature would place C. rishii sp. n. within the 'salinarius group'. However, this is not a group in the systematic sense, but an artificial grouping equivalent to a morphotype that reflects only the tubule character state. It is suggested that the absence of tubules is an adaptation for tolerating a wide range of salinity levels, however the 'salinarius group' had been also recorded in freshwater environments. Here, larvae without abdominal tubules were found in an environment with low levels of salinity, which indicates that the tubule condition may be result of further abiotic pressures, and configures a rather enigmatic scenario to this feature, particularly when considered the fact that larvae of Chironomus having tubules had also been recorded at the same habitat, living under similar conditions of C. rishi sp. n.

Brazilian Pseudochironomini (Diptera: Chironomidae) Part 2. New Pseudochironomus and Riethia species.

In this second part of the study about Brazilian Pseudochironomini Sæther (Diptera: Chironomidae: Chironominae), seven new species are described and illustrated. Three species belong to the genus Pseudochironomus; they are: Pseudochironomus capivara sp. n., Pseudochironomus ariquemis sp. n. and Pseudochironomus boraceia sp. n. all are described from males, the first as pupa, the second as larva and pupa also. Four species belong to Riethia: Riethia cauame sp. n., Riethia fazzari sp. n., Riethia galilei sp. n. and Riethia pantera sp. n. all described as male. Except for R. fazzari sp. n. and P. boraceia sp. n. collected in São Paulo State, the remaining species were collected in Amazon region. A key of males to known species of Brazilian Pseudochironomini is given.

Madicolous Chironomidae from the Brazilian Atlantic Forest: a checklist with notes on altitudinal distributions (Diptera, Insecta).

Thin layers of water running over rocky surfaces are characteristic of madicolous habitats, which harbor a peculiar Chironomidae community. However, information on the identity, distribution, and ecology of madicolous chironomids in the Neotropical region are still sparse. The main purpose of this research is to reveal and contribute to the ecology of madicolous Chironomidae species, especially regarding their altitudinal distribution in the Atlantic Forest. Sampling was performed using our own designed emergence traps deployed from 0 to 2700 m a.s.l. in 70 sites in three mountains in southeastern Brazil. Sixty taxa of chironomids were collected and identified, of which only 22 are known to science. Most of the species showed a wider distribution than previously known, both in terms of geographic and altitudinal ranges, while others showed significant association with particular altitudinal bands (as evidenced by the indicator species analysis). Atlantic Forest mountainous regions are known to harbor one of the richest fauna in the world and have been suffering from several types of environmental impacts, including climate change, which will especially affect taxa living in specialized habitats. The narrow range of tolerance to environmental conditions verified for mountain species, and the fact that many of them are rare and endemic, make the conservation efforts in these areas indispensable.

Tanytarsini (Diptera: Chironomidae) from madicolous habitat in Southeast Brazil: new species and new records.

Tanytarsini (Diptera: Chironomidae: Chironominae) collected from madicolous habitats in Brazil are analyzed, and three new species of Tanytarsus van der Wulp are described and illustrated: T. angelae sp. n. and T. alaidae sp. n. as adult male and T. alienus sp. n. as male and female. New records of another Brazilian Tanytarsus species are also presented, and immature stages of Paratanytarsus silentii Trivinho-Strixino are described.

A systematic study on Endotribelos Grodhaus (Diptera: Chironomidae) from Brazil including DNA barcoding to link males and females.

Six new species of Endotribelos from Brazil are described and illustrated as male, female, pupa and larva: E. bicolor sp. n., E. fulvidus sp. n., E. jaragua sp. n., E. jiboia sp. n., E. semibruneus sp. n. and E. sublettei sp. n. The female of E. calophylli Roque & Trivinho-Strixino and the larvae of four unknown morphotypes are also described. Keys including males and larvae of all known species of Endotribelos are provided. Adults' males and females from five species were linked using DNA Barcoding mtCOI sequences.

The invasive white ginger lily ( Hedichium coronarium ) simplifies the trait composition of an insect assemblage in the littoral zone of a Savanna reservoir

ABSTRACT The invasive white ginger lily (Hedichium coronarium - J. Köenig, 1783) simplifies the trait composition of an insect assemblage in the littoral zone of a Savanna reservoir. Invasive plants are believed to shift the trait composition of aquatic insects dwelling in banks of lentic ecosystems. In this study, we analyzed the relationship between the presence of the invasive white ginger lily (H. coronarium) and the functional trait indices of the aquatic insect assemblage in the littoral zone of a tropical reservoir. We sampled aquatic insects on the invaded and non-invaded banks of the reservoir and then analyzed the insect trait indices by estimating the Functional Dispersion (FDis), Functional Evenness (FEve) and the Functional Divergence (FDiv), as well as the Community level Weight-Mean traits (CWM). Finally, we compared these indices between invaded and non-invaded banks as well as their relationship with the abiotic variables, such as dissolved oxygen, pH, depth and water temperature. The result confirmed that the invaded banks had lower values of functional indices as well as dissolved oxygen. However, this abiotic variable was found to have no effect on the functional indices. In addition, the white ginger lily bank presented higher contribution of collector-gathering to predator-piercer groups. We suggest that the invasion of white ginger lily promotes low heterogeneity habitat resulting in simplification on functional traits of aquatic insect assemblage.

New species of Tanytarsus van der Wulp (Diptera: Chironomidae) from São Paulo State, Brazil.

Tanytarsus lenyae sp. n., T. giovannii sp. n., T. fittkaui sp. n. and T. alfredoi sp. n. from São Paulo State (Brazil) are described and diagnosed, the first as adult male and pupa, and the remaining as male, pupa and larva. The species were collected in areas of Cerrado, at the boundaries of São Carlos city. Complete diagnoses and drawings of the species are given. The imagos can be separated from other species of Tanytarsus van der Wulp mainly by differences in the antennal ratio, dorsomedian extension of the eyes, the thorax and wing setation, the shape of anal tergal bands, the anal point armament and the shape of superior volsella, digitus and median volsella. The pupae are characterized by the thoracic horn armament, the arrangement of the precorneals, the shape of anal comb and the abdominal setation. The larvae can be separated by differences in the antennal pedestal, the sclerotization of the second antennal segment, the size of Lauterborn organ pedicels, the shape of the clypeal seta S3 and the sclerotization of the mentum. Apparently, the four new species are not closely related, and the anal point armament alone would be enough to separate one species from the other.

Chironomus amissum sp. n. (Diptera, Chironomidae) from southeastern Brazil

The paper presents a description of larva, pupa, imago (male) and karyotype of Chironomus amissum from southeastern Brazil. It belongs to pseudothummi cytocomplex with 2n=8 and chromosome arm combinations: AE BF CD G. Several fixed homozygous inversions distinguished arm A of the new species from that of Chironomus columbiensis Wülker et al. 1989 and Chironomus anonymus Williston, 1896. One homozygous inversion of arm F differentiated it from C. anonymus. Species-specific characters were presented in the larva, pupa and imago.

Neste artigo é apresentada a descrição de larva, pupa, adulto macho e cariótipo de Chironomus amissum, uma nova espécie do sudeste brasileiro. Ela pertence ao citocomplexo pseudothummi com 2n=8 e cromossomos com combinações de braços: AE BF CD G. Várias inversões homozigóticas diferem o braço A da nova espécie em relação às espécies Chironomus columbiensis Wülker et al. 1989 e Chironomus anonymus Williston, 1896. Uma inversão homozigótica do braço F diferencia essa espécie de C. anonymus. Caracteres que diferenciam a espécie nova são também apresentados para larva, pupa e adulto.

First record of larvae of Chironomidae (Insecta, Diptera) as prey of Temnocephala sp. (Platyhelminthes, Temnocephalidae), an ectosymbiont on larvae of Corydalidae (Megaloptera) / Primeiro registro de larvas de Chironomidae como presas de Temnocephala sp. (Platyhelminthes, Temnocephalidae), um ectosimbionte de larvas de Corydalidae (Maegaloptera)

First record of larvae of Chironomidae (Insecta, Diptera) as prey of Temnocephala sp. (Platyhelminthes, Temnocephalidae), an ectosymbiont on larvae of Corydalidae (Megaloptera). This study constitutes the first record of Temnocephala Blanchard, an ectosymbiont on Corydalidae, as a possible predator of chironomid larvae. Twenty-eight Corydalidae larvae (Corydalus and Protochauliodes) were examined under stereomicroscopic in search for Temnocephala and Chironomidae larvae, of which five megalopteran larvae had 24 Temnocephala sp. associated. Furthermore, eight of these Temnocephala worms had chironomid larvae in their gut contents, an interaction previously unknown. Gut content analyses revealed Corynoneura as the commonest chironomid, but larvae of Larsia, Rheotanytarsus and Tanytarsus were recorded as well. This study included Corydalus and Protochauliodes as hosts for Temnocephala, which might be important for this worm dispersion and population dynamics.

Primeiro registro de larvas de Chironomidae como presas de Temnocephala sp. (Platyhelminthes, Temnocephalidae), um ectosimbionte de larvas de Corydalidae (Maegaloptera). Este estudo constitui o primeiro registro de Temnocephala Blanchard (Platyhelminthes, Temnocephalidae), um ectosimbionte em larvas de Megaloptera, como um possível predador de larvas de Chironomidae. Vinte e oito larvas de Corydalidae (Corydalus e Protochauliodes) foram examinadas sobre estereomicroscópio na busca por Temnocephala e larvas de Chironomidae, das quais cinco larvas de Megaloptera continham 24 Temnocephala sp. associadas. Além disso, oito Temnocephala possuíam em seu conteúdo estomacal larvas de Chironomidae, uma interação desconhecida anteriormente. A análise do conteúdo estomacal revelou Corynoneura como o quironomídeo mais abundante, e também algumas larvas de Larsia, Rheotanytarsus e Tanytarsus. Este estudo inclui Corydalus e Protochauliodes como hospedeiros de Temnocephala, os quais podem ser importantes para a dispersão e dinâmica populacional desses vermes.

Kinetics of the aerobic decomposition of Talauma ovata and Saccharum officinarum / Cinéticas da decomposição aeróbia de Talauma ovata e Saccharum officinarum

The aim of this study is to evaluate the kinetics of aerobic decomposition of Saccharum officinarum and Talauma ovata leaves. For each species, decomposition chambers (leaves and water) were set up, which were maintained under controlled conditions. Each sampling day (1, 7, 15, 30, 39, 58, 72 and 90 days), the concentrations of total organic carbon, pH and electrical conductivity (EC) were determined in the dissolved fraction, while the mass and cell wall fractions (CWF) were determined in the particulate fraction. The pH stabilization of the chambers with T. ovata and S. officinarum leaves occurred in alkaline (ca. 8 - 8.5) and close to the neutrality (ca. 7 - 7.5) environment, respectively. The EC values were on average 1.6 times higher in incubations with T. ovata leaves. The mass loss did not differ between the species (mean = 53.85%), however the decay coefficient was higher for S. officinarum (k4 = 0.007 day-1) than for T. ovata (k4 = 0.005 day-1) leaves. The CWF mass loss (mean = 50.16%) and their coefficient (0.0090 day-1) were similar. S. officinarum decomposed faster due to its high concentrations of energetic compounds of interest to the microbiota. The slower decomposition of T. ovata may have occurred due to the presence of secondary compounds with negative effects to the microorganisms.

O objetivo deste estudo foi avaliar as cinéticas da decomposição aeróbia de folhas de Talauma ovata e Saccharum officinarum. Para cada espécie foram montadas câmaras de decomposição (folhas e água) que foram mantidas sob condições controladas. A cada dia amostral (1, 7, 15, 30, 39, 58, 72 e 90 dias), as concentrações de carbono orgânico total, pH e condutividade elétrica (CE) foram determinadas na fração dissolvida, enquanto a massa e as frações de parede celular (FPC) foram determinadas na fração particulada. A estabilização do pH das câmaras com folhas de T. ovata e S. officinarum ocorreram em meio básico (ca. 8 - 8,5) e próximo à neutralidade (ca. 7 - 7,5), respectivamente. Os valores de CE foram em média 1,6 vezes maiores nas incubações com folhas de T. ovata. A perda de massa não diferiu entre as espécies (média = 53,85%). No entanto, o coeficiente de decaimento foi maior para as folhas de S. officinarum (k4 = 0,007 dia-1) que para T. ovata (k4 = 0,005 dia-1). As perdas de massa da FPC (média = 50,16%) e seus respectivos coeficientes (0,0090 dia-1) foram similares. S. officinarum decompôs mais rapidamente devido às elevadas concentrações de compostos energéticos de interesse para a microbiota. A decomposição mais lenta de T. ovata pode ter ocorrido pela presença de compostos secundários com efeitos negativos sobre os micro-organismos.

Kinetics of the aerobic decomposition of Talauma ovata and Saccharum officinarum - doi: 10.4025/actascibiolsci.v34i4.9396

The aim of this study is to evaluate the kinetics of aerobic decomposition of Saccharum officinarum and Talauma ovata leaves. For each species, decomposition chambers (leaves and water) were set up, which were maintained under controlled conditions. Each sampling day (1, 7, 15, 30, 39, 58, 72 and 90 days), the concentrations of total organic carbon, pH and electrical conductivity (EC) were determined in the dissolved fraction, while the mass and cell wall fractions (CWF) were determined in the particulate fraction. The pH stabilization of the chambers with T. ovata and S. officinarum leaves occurred in alkaline (ca. 8 - 8.5) and close to the neutrality (ca. 7 - 7.5) environment, respectively. The EC values were on average 1.6 times higher in incubations with T. ovata leaves. The mass loss did not differ between the species (mean = 53.85%), however the decay coefficient was higher for S. officinarum (k4 = 0.007 day-1) than for T. ovata (k4 = 0.005 day-1) leaves. The CWF mass loss (mean = 50.16%) and their coefficient (0.0090 day-1) were similar. S. officinarum decomposed faster due to its high concentrations of energetic compounds of interest to the microbiota. The slower decomposition of T. ovata may have occurred due to the presence of secondary compounds with negative effects to the microorganisms.

Concordance between macroinvertebrate communities and the typological classification of white and clear-water streams in Western Brazilian Amazonia / Concordância entre comunidade de macroinvertebrados e classificação tipológica de igarapés em águas brancas e claras no oeste Amazônico, Brasil

In this study we have attempted to answer whether there is correspondence between aquatic macroinvertebrate communities and the typological classification of white and clean-water streams in western Amazonia lowlands. We worked within two distinct hydrographic basins: Moa River catchment (clear-water streams) and Azul River catchment (white-water streams) in Serra do Divisor National Park, Acre State, Brazil, sampling 10 streams in each basin. A total of 2,952 individuals were collected, distributed among 134 taxa. Our results show that macroinvertebrate communities, at genus as well as family level, are in concordance to a priori classifications that distinguish between white and clear water streams. The main implication of our results for biomonitoring is that biotic variation between white and clear streams can be partitioned regionally, which would improve the bioassessment accuracy of the Amazonian streams.

Neste trabalho, nós investigamos se há correspondência entre comunidade de macroinvertebrados e classificação de igarapés em águas claras e brancas no oeste da Amazônia. Nós trabalhos em duas bacias hidrográficas, Rio Moa (águas claras) e Rio Azul (águas brancas) no Parque Nacional da Serra do Divisor, Acre, Brasil, amostrando 10 igarapés em cada bacia. Coletamos 2952 indivíduos, distribuídos em 134 taxa. Nossos resultados mostram que a comunidade de macroinvertebrados, identificada com baixa e alta resolução taxonômica, responde claramente a classificação tipológica de igarapés em águas claras e brancas.A principal implicação dos nossos resultados no âmbito de biomonitoramento é que a partição da variação biótica entre igarapés de águas claras e brancas pode melhorar a racionalidade e implantação de sistemas de avaliação ambiental na Amazônia.

Chironomidae (Insecta, Diptera, Nematocera) do Estado de São Paulo, Sudeste do Brasil / Chironomidae (Insecta, Diptera, Nematocera) from São Paulo State, Southeast of Brazil

É apresentado um inventário atualizado (junho/2010) das espécies de Chironomidae do Estado de São Paulo. Ao todo são listadas 149 espécies (91 Chironominae, 44 Orthocladiinae, 13 Tanypodinae e 1 Podonominae) acompanhadas de informações sobre os estágios de vida conhecidos e comentários adicionais sobre alguns táxons com nomenclatura duvidosa e/ou modificada.

In this paper we present an updated inventory (June/2010) of the Chironomidae species from the State of São Paulo. Altogether 149 species are listed (91 Chironominae, 44 Orthocladiinae, 13 Tanypodinae and 1 Podonominae) accompanied by information about the known life stages and additional comments on some taxa with dubious nomenclature and / or modified nomenclature.

Larval description of Simulium (Notolepria) cuasiexiguum and Simulium (Chirostilbia) obesum and new records of black fly species (Diptera: Simuliidae) in the states of São Paulo and Minas Gerais, Brazil.

We describe the larval stage of Simulium cuasiexiguum Shelley, Luna Dias, Maia-Herzog & Lowry and Simulium obesum Vulcano and provide new distribution records of four black fly species in the State of São Paulo (Simulium cuasiexiguum, Simulium metallicum s.l. Bellardi, Simulium stellatum Gil Azevedo, Figuer6 & Maia-Herzog and Simulium oyapockense s.l. Floch & Abonnenc) and three species in the State of Minas Gerais (Simulium duodenicornium Pepinelli, Hamada & Trivinho-Strixino, Simulium obesum and Lutzsimulium pernigrum Lutz).

Assessment of chromium contamination in the Monte Alegre stream: a case study

The aim of this work was to study the contamination by chromium in the sediments of the Monte Alegre stream and in the larvae of Odonata and the possible impact caused by them on the stream macroinvertebrates community. It was found that chromium contaminated the sediments and the aquatic biota. Although, the stream macroinvertebrates community structure did not appear to be modified.