Resumo Amostras biológicas obtidas de uma pequena lagoa temporária do norte da Colômbia proporcionaram o primeiro registro de Coronatella undata Sousa, Elmoor-Loureiro e Santos, 2015 e do macho de Coronatella monacantha (Sars, 1901) na Colômbia. Neste estudo, foi descrita a morfologia de fêmeas de C. undata e de fêmeas e machos de C. monacantha, comparando-a com outras espécies do gênero. Coronatella undata foi descrita originalmente no Brasil e, entre as espécies do complexo C. monacantha, parece estar intimamente relacionada com Coronatella acuticostata (Sars, 1903). Coronatella undata apresenta algumas semelhanças com C. monacantha, mas pode ser identificada por seus principais caracteres, tais como: 1) ângulo posterior ventral da valva com dois dentículos; 2) cerda rudimentar no exopodito do ramo do tronco II; 3) filtro da gnatobase do apêndice torácico II com seis cerdas; 4) cerda ODL do membro do tronco I mais curta que a cerda mais longa do IDL. Coronatella monacantha é a espécie mais relatada na região neotropical, e o macho se assemelha mais a Coronatella paulinae Sousa, Elmoor-Loureiro & Santos em relação à/ao: (i) razão comprimento / largura do pós-abdômen, (ii) espinho basal quase reto e (iii) espinho basal longo com a metade do comprimento do espinho basal. No entanto, eles podem ser separados pelo/pela: (i) número de cerdas laterais na antênula, (ii) ângulo postanal, (iii) posição do gonóporo e (iv) presença de dentículo no canto ventral posterior da valva.

Abstract Biological samples obtained from a small temporary pond of northern Colombia yielded the first record Coronatella undata Sousa, Elmoor-Loureiro and Santos, 2015 and of the male of C. monacantha (Sars, 1901) for Colombia. In this study, the morphology of female of Coronatella undata and female and male of C. monacantha was described and compared to other species within the genus. C. undata was originally described from Brazil and, among the species of the Coronatella monacantha complex, seems to be closely related to C. acuticostata (Sars, 1903). C. undata shows some similarities with C. monacantha, but it can be identified by important diagnostic characters such as: 1) posterior-ventral corner of valve with two denticles, 2) seta on exopodite of trunk limb II rudimentary, 3) filter comb of trunk limb II with six setae, 4) ODL seta of trunk limb I shorter than longest seta of IDL. C. monacantha is the most reported species in the Neotropical region and the male most resemble C. paulinae Sousa, Elmoor-Loureiro & Santos, 2015 in relation to (i), length/wide of postabdomen ratio (ii) basal spine almost straight and (iii)) long basal spine reaching the mid-length of basal spine. However, they can be separated by (i) number of lateral seta on the antennule, (ii) postanal angle, (iii) position of gonopore (iv) presence of a denticle on posterior-ventral corner of valve

Abstract Our knowledge of cladoceran species composition and distribution of Neotropical taxa is incomplete, therefore misleading the basic understanding of biodiversity processes and biogeographical patterns of this ecologically relevant group. We present new records and an updated checklist of the cladocerans of Rio de Janeiro State (Brazil) based on a critical review of their known distribution throughout the different freshwater ecoregions. Nine marine species were recorded, and 80 non-marine cladocerans were counted from two of the four ecoregions of Rio de Janeiro State. We estimate species richness applying the interpolation and extrapolation method, using iNEXT function. With this approach we compute diversity estimates for rarefied and extrapolated samples up to double the reference sample size (number of studies). Four new records of rare species were included from surveys in the Paraiba do Sul ecoregion. The Fluminense ecoregion shows a higher richness with a more asymptotic curve and thus a lower expected richness in comparison to the Paraiba do Sul ecoregion. Ceriodaphnia cornuta Sars, 1886 was the most frequently found species whilst Moina macrocopa Straus, 1820 was the only non-native species encountered. Our study can contribute to developing a biogeographical understanding of this diverse group in a heterogeneous territory in terms of inland waters. Future studies are suggested to prioritize novel ecoregions and unexplored habitats e.g. littoral zones with high macrophyte and periphyton coverage, brackish waters, saline and high-altitude lakes, as more diverse and heterogeneous habitats will undoubtedly reveal additional records.

Abstract Despite the rising interest in cladoceran biogeography worldwide, many species distributions are still unknown to science, especially in naturally rich freshwater of the Neotropics. Herein we present a checklist of the taxa, giving the distributions of the valid species throughout 13 hydrographic basins within the two freshwater ecoregions of Northeastern Mata Atlântica and São Francisco. Superorder Cladocera comprises 72 known species in Bahia State classified into two orders: the Anomopoda, represented by Chydoridae (36 spp), Daphniidae (7), Macrothricidae (6), Bosminidae (4), Moinidae (3) and Ilyocryptidae (2); and Ctenopoda, represented by Sididae (8 spp). Species from the orders Onychopoda and Haplopoda are still lacking in Neotropical waters. The first compilation of the data on the Cladocera of Bahia, Brazil, is represented by this checklist and contains 38 new records for the state. Critical remarks on species distributions, as well as detailed information on sampling sites and geographic coordinates are also included.

Abstract Although the cladoceran Anthalona neotropica Sousa, Elmoor-Loureiro and Debastiani-Júnior, 2015 has a wide geographic range in Brazil, until now, it has only been reported in a few localities. The present study reports the occurrence of this species in the estuaries of the Jequitinhonha River and Una River, representing the first records of An. neotropica in Bahia State, Brazil.

Abstract Flavalona asymmetrica sp. nov. belongs to the costata-clade. This species has two main head pores, a feature shared only with Flavalona setigera (Brehm, 1931). Morphological differences between them are related to main and lateral head pores, armature of scrapers on the second limb, and proportion of setae on the third and fourth limbs, number of denticles on the postabdomen. Males of F. asymmetrica sp. nov. has genital process about ten times shorter than length of postabdominal claw, which is an exclusive morphological trait. Flavalona asymmetrica sp. nov. is a Neotropical species, so far, it occurs only in Brazil and can be found together with Flavalona iheringula (Sinev & Kotov, 2004) and Flavalona margipluma (Sousa, Santos, Güntzel, Diniz-Filho, de Melo-Júnior & Elmoor-Loureiro, 2015).

Abstract Until recently, Lake Paranoá was considered the most thoroughly studied aquatic environment in relation to cladocerans in the Federal District. However, in new samplings carried out during the dry and rainy seasons of 2014, we found 10 new records of species. These species were presumed to occur in Lake Paranoá because of their range of geographical distribution. The male of Leydigiopsis ornata Daday, 1905 is described for the first time, adding new morphological traits to a recent redescription of the species. The presence of three rows of setulae on the labral keel is unique to the L. ornata male. As is the case in females, the male of L. ornata is mainly differentiated from L. megalops Sars, 1901 and L. curvirostris Sars, 1901 by the morphology of the postabdomen.

Abstract Cladoceran males are not very frequent in natural populations, since they are only produced in stress situations. Thus, only a few species have had the male morphology described. Nevertheless, whenever data concerning the morphology of males is available, they are used as a tool to resolve taxonomic problems. In this study, the morphology of Coronatella paulinae Sousa, Elmoor-Loureiro and Santos, 2015 (Cladocera: Chydoridae) was described and compared to other species within the genus. Coronatella paulinae shares the diagnostic morphological traits typically attributed to the genus: (1) gonopores opening ventrally, subapically to the postabdominal claw; (2) marginal setulae arranged in groups on the postanal margin; (3) Inner Distal Lobe (IDL) armed with three setae, of which one is the male seta. The absence of lateral aesthetascs on male antennules might also be an important diagnostic character for the genus, since they are present in other Aloninae groups. Coronatella paulinae males present a unique combination of morphological traits on the postabdomen, which distinguish them from other Coronatella Dybowsky and Grochowski, 1894 species, such as a marked postanal angle and an almost straight basal spine, longer than the mid-length of the postabdominal claw.

Described from a high-altitude lake in Peru, Bosmina huaronensis Delachaux, 1918 has been recorded in diverse kinds of water bodies in South and North America, suggesting that this species has high environmental tolerance and a wide niche breadth. The present study surveyed the occurrence records of B. huaronensis from 55 localities and, using multivariate analysis, investigated the niche differentiation among populations from different biogeographic regions, based on altitude and seven climatic variables. The first two principal components (PC) explained 73% of the overall variance. PC1 was related to annual mean temperature, precipitation of driest quarter, and annual precipitation. PC2 was related to temperature seasonality and precipitation of wettest quarter. The PCA diagram showed three population groups, occupying different climate niches: (1) tropical highlands; (2) Neotropical lowlands; (3) temperate zones of both hemispheres. These results point to the need for further evaluation of these populations under morphological, genetic and ecological aspects.

Através de amostragens rápidas, levantou-se as espécies de cladóceros fitófilos presentes em zonas litorâneas de rios, lagoas e brejos permanentes e temporários do vale do Rio Paranã, Goiás, Brasil. Foram encontradas 39 espécies, das quais 22 são registradas pela primeira vez na região central do Brasil. São discutidos aspectos da taxonomia de algumas dessas espécies. A análise de agrupamento (UPGMA) dos pontos de amostragem mostrou dois tipos de associações de espécies de cladóceros fitófilos, caracterizadas pela maior ou menor riqueza e abundância relativa das espécies das famílias Daphniidae e Moinidae (filtradoras), em contraste com as famílias dominantes Chydoridae e Macrothricidae, tipicamente raspadoras do substrato.

A rapid assessment survey identified 39 phytophilous cladocerans species from littoral zones of rivers, permanent and temporary lagoons, and swamps of the Paranã River Valley, Goiás, Brazil, 22 are registered for the first time in Central Brazil. Aspects of the taxonomy of some of these species are discussed. Cluster analysis (UPGMA) revealed two phytophilous cladoceran assemblages, characterized by higher or lower richness and relative abundance of species of the families Daphniidae and Moinidae (filter feeders), in comparison with the dominant families Chydoridae and Macrothricidae (scraper feeders).

Foi conduzida uma análise cladística dos gêneros sul-americanos de Macrothricidae (Crustacea, Cladocera, Radopoda) com base em 36 caracteres morfológicos e incluindo 15 taxa terminais (três como grupos externos). Uma única árvore foi obtida pela análise, a qual suporta o monofiletismo de Macrothricidae e de Macrothricinae. O grupo chamado de "não-Macrothricinae" é indicado como parafilético. Neothricidae também não encontrou suporte.

A cladistic analysis of the genera of the Macrothricidae (Crustacea, Cladocera, Radopoda) was performed based on 36 morphological characters, and including 15 terminal taxa (three as outgroups). The single tree obtained from this analysis supported the monophyly of Macrothricidae and Macrothricinae. The group called as "non-Macrothricinae" was indicated as paraphyletic. Neothricidae was also not supported.

The cladoceran Kurzia polyspina Hudec, 2000 (Anomopoda, Chydoridae) was found associated with Eichhornia Kunth, 1843 (Pontederiaceae) roots in Paranoá Lake, Brasília. It represents the first record of this species in Brazil and in the Southern Hemisphere. Comments on Kurzia Dybowski & Grochowski, 1894 South American records are included.

In order to verify the existence of seasonal variations in morphology of Bosmina longirostris and Bosmina hagmanni, samples were taken from Paranoá Lake (Brasília, DF) during 1983. Body length and breadth, antennule, mucro and eye diameter were measured. Alometry rates were also calculated. It was verified that throughout the year both Bosmina species presented variation involving the five measures. The measures, except the antennule and mucro of B. longirostris, depend, at least partially, on the size of the individual and, therefore, on the age structure of the population. The antennule and mucro variations of B. hagmanni were strongly related to alometry rates. For B. longirostris the antennule and mucro variations appeared to be related to phenomena in an embryonic phase.