Contribution to the knowledge of the genus Vestalenula Rossetti & Martens, 1998 (Crustacea, Ostracoda, Darwinulidae), with the description of a new species, V. carinata n. sp., from the island of Florianópolis, Brazil.

The genus Vestalenula is the most species rich in the putative ancient asexual ostracod Family Darwinulidae. Several new Recent species were described from various continents, mostly based on carapace shape and structure. These species were found in a variety of aquatic and (semi-) terrestrial habitats, including springs, streams, interstitial waters, leaf litter in forests and in splash zones of waterfalls. Here, we describe V carinata n. sp. from moist leaf litter, collected from the Brazilian island of Florian6polis. The species belongs to the danielopoli-lineage within the genus because of its elongated internal tooth in the left valve and elongated external keel on the right valve. It can be distinguished from all other species in this group by its size, its L/H ratio and the relative length of the keel. The relationship of this new species to the enigmatic, putative marine species Senidarwinula terraenuxforna Choe, 1988, is discussed. An identification key to species of the genus is provided.

Six new species of Elpidium Müller, 1880 (Podocopida: Limnocytheridae) from Eastern Brazil.

Elpidium is the most common ostracod genus occurring in phytotelmata in the Neotropical region, with distributions ranging from Florida, USA in the north to Rio Grande do Sul, Brazil in the south. However, the genus remains poorly known both in terms of diversity and of the distributional pattern of its species. Here, we describe six new species of Elpidium, E. oxumae n. sp., E. cordiforme n. sp., E. picinguabaense n. sp., E. eriocaularum n. sp., E. higutiae n. sp., E. purium n. sp., all from phytotelm environments in the Brazilian Atlantic rain forest. In addition, we discuss the distributional pattern and endemicity levels of Elpidium species in the light of these new taxonomic results and argue about possible misunderstandings on the distribution of the type species E. bromeliarum.

A New Species of Elpidium (Crustacea: Ostracoda: Limnocytheridae) from Brazil and a Morphological Phylogenetic Proposal for the Genus.

Elpidium species exclusively inhabiting confined and temporary environments, such as those of tank-bromeliads, are a source of interesting and diverse studies on taxonomy, evolution and ecology, to name a few. However, despite its great diversity of species or potential for study, this genus (and other phytotelm members) has been poorly studied. In the last years, however, description of Elpidium species increased from six before 2013 to 11 today. This study is an effort to keep uncovering its great diversity and to go further in order to deeply understand the genus Elpidium. To this end, this study describes another species in the genus, Elpidium litoreum sp. nov., and proposes a phylogenetic reconstruction of it based on morphological characters. Our results point to the monophyly of Elpidium and puts Intrepidocythere ibipora as its sister-group. Although the phylogeny revealed some interesting relations, it also exposed some incongruities that ultimately demonstrate how superficial the current knowledge about the genus is. All these questions are discussed in detail. We see this work as at the same time an effort to better understand Elpidium and a stimulus to other researches to turn their attention to the historically neglected phytotelmata community.

Richness and composition of Cladocera (Crustacea: Branchiopoda) in Brazilian rupestrian cerrados, with comments on distribution and taxonomy.

Several studies that involve a faunal survey of Cladocera in Brazil have been carried out in recent years; however, knowledge of the distribution and diversity of species of this group in semiterrestrial and aquatic bodies of rupestrian cerrado is still rare. The present study evaluated the richness and composition of cladoceran species in these environments in the central parts of the country. Samples were collected at nine sites of rupestrian cerrado from 2011 to 2012. In total, 47 cladocerans species were identified, belonging to six families, emphasizing the Chydoridae family with the greatest richness (32 species) and abundance. The species Bryospilus repens had its first record for the state of Goiás and the Brazilian Midwest. Other species were also recorded for the first time: Leberis davidi for the state of Minas Gerais, and Alona yara and Flavalona asymmetrica for the state of Bahia. This demonstrates that rupestrian cerrados are relevant for cladoceran diversity on a regional scale. Carrying out new inventories of cladocerans in similar phytophysiognomies could contribute significantly to the knowledge of the biodiversity of these animals in Brazil, in addition to providing updates on the geographic distribution of species already recorded in previous studies.

Phylogenetic position of the acariform mites: sensitivity to homology assessment under total evidence.

BACKGROUND: Mites (Acari) have traditionally been treated as monophyletic, albeit composed of two major lineages: Acariformes and Parasitiformes. Yet recent studies based on morphology, molecular data, or combinations thereof, have increasingly drawn their monophyly into question. Furthermore, the usually basal (molecular) position of one or both mite lineages among the chelicerates is in conflict to their morphology, and to the widely accepted view that mites are close relatives of Ricinulei. RESULTS: The phylogenetic position of the acariform mites is examined through employing SSU, partial LSU sequences, and morphology from 91 chelicerate extant terminals (forty Acariformes). In a static homology framework, molecular sequences were aligned using their secondary structure as guide, whereby regions of ambiguous alignment were discarded, and pre-aligned sequences analyzed under parsimony and different mixed models in a Bayesian inference. Parsimony and Bayesian analyses led to trees largely congruent concerning infra-ordinal, well-supported branches, but with low support for inter-ordinal relationships. An exception is Solifugae + Acariformes (P. P = 100%, J. = 0.91). In a dynamic homology framework, two analyses were run: a standard POY analysis and an analysis constrained by secondary structure. Both analyses led to largely congruent trees; supporting a (Palpigradi (Solifugae Acariformes)) clade and Ricinulei as sister group of Tetrapulmonata with the topology (Ricinulei (Amblypygi (Uropygi Araneae))). Combined analysis with two different morphological data matrices were run in order to evaluate the impact of constraining the analysis on the recovered topology when employing secondary structure as a guide for homology establishment. The constrained combined analysis yielded two topologies similar to the exclusively molecular analysis for both morphological matrices, except for the recovery of Pedipalpi instead of the (Uropygi Araneae) clade. The standard (direct optimization) POY analysis, however, led to the recovery of trees differing in the absence of the otherwise well-supported group Solifugae + Acariformes. CONCLUSIONS: Previous studies combining ribosomal sequences and morphology often recovered topologies similar to purely morphological analyses of Chelicerata. The apparent stability of certain clades not recovered here, like Haplocnemata and Acari, is regarded as a byproduct of the way the molecular homology was previously established using the instrumentalist approach implemented in POY. Constraining the analysis by a priori homology assessment is defended here as a way of maintaining the severity of the test when adding new data to the analysis. Although the strength of the method advocated here is keeping phylogenetic information from regions usually discarded in an exclusively static homology framework; it still has the inconvenience of being uninformative on the effect of alignment ambiguity on resampling methods of clade support estimation. Finally, putative morphological apomorphies of Solifugae + Acariformes are the reduction of the proximal cheliceral podomere, medial abutting of the leg coxae, loss of sperm nuclear membrane, and presence of differentiated germinative and secretory regions in the testis delivering their products into a common lumen.

On three new species of Elpidium Müller, 1880 and the re-description of Elpidium laesslei (Tressler, 1956) from Jamaica (Ostracoda: Podocopida: Limnocytheridae).

Elpidium ostracods are known by their very particular niche (water accumulated in tank-bromeliads), their relatively low dispersal ability and their dependency on amphibians for dispersal and colonization of new bromeliads. All these characteristics make the genus an interesting group for evolutionary, ecological and even taxonomic studies. However, the diversity of the group remains poorly studied. Here, we describe three new species of Elpidium, Elpidium littlei n. sp., Elpidium heberti n. sp. and Elpidium wolfi n. sp., and re-describe Elpidium laesslei, all from Jamaica. These species are characterized by a copulatory process with separated ejaculatory duct and distal glans, a feature so far unique within the genus. Each species can, in turn, be diagnosed by soft part and carapace morphology, most notably comparing hemipenis, valve ornamentation and degree of sexual dimorphism. The observed morphological diversity of Elpidium is discussed in relation to previous genetic estimates that suggested an even higher diversity in Jamaica. We point to intraspecific variation and lack of complete morphological descriptions as possible explanations. We also reaffirm the need of multidisciplinary studies in order to do more objective and secure taxonomic classifications in future studies.

Description of a new species of Spongiopsyllus Johnsson, 2000, and redescriptions of Parmulodes verrucosus Wilson, 1944 and Entomopsyllus stocki Kim, 2004 with revised diagnosis of Entomopsyllus (Copepoda, Siphonostomatoida, Entomolepididae).

The Family Entomolepididae is composed by 7 genera and 15 species. During a survey on the known species and the search for new species, a new Spongiopsyllus is described associated with sponge Aplysina insularis. The new species has antennule 14-segmented, four setae on both lobes of maxillule, some unique features on the leg setation and the armature of the maxilliped. These characteristics make the new species different from all other congeners in Spongiopsyllus. The diagnosis of Entomopsyllus was also revised once it does not consider the differences to Spongiopsyllus which was created posteriorly to its erection. An analysis of Entomopsyllus stocki also indicated that leg 5 somite and the genital somite are fused, instead of separated as originally stated, the structure is also redescribed. Finally, Parmulodes verrucosus is studied and an up-to-date description is provided, correcting some inconsistencies in the armature formula of the antennule and the leg setation, and providing re-analysis of the other appendages.

A new species of Notodiaptomus from the Amazon basin (Crustacea, Copepoda, Calanoida, Diaptomidae).

A new Diaptomidae species is presented from the Neotropical region. It was found in two Amazonian lakes, Ressaca and Arapujá, both in Pará State, Brazil. The lakes are 400 km apart and threatened by the building of reservoirs for hydropower generation and pollution by human settlements. The new species resembles N. paraensis Dussart & Robertson, 1984, but it can be distinguished from this species and other congeners in having a special process on the fifth leg basis of the male, by the place of insertion of lateral spine in the last segment of right P5 of male, the shape and relationship between length and width of segments of male and female P5 exopodite 2 with stout inner process bearing short setules and outer small spine, exopodite 3, with two terminal setae, outer smaller; endopodite 1-segmented with one subterminal seta and oblique comb of spinules, the presence of a line of dorsal spinules at the distal margin of thoracic somites in both sexes. A brief comparison with other Notodiaptomus species is presented in the discussion.

First record of Clausidium (Copepoda, Clausidiidae) from Brazil: a new species associated with ghost shrimps Neocallichirus grandimana (Gibbes, 1850) (Decapoda, Callianassidae).

A new clausidiid copepod was found living in galleries of ghost shrimps Neocallichirus grandimana (Gibbes, 1850) in Natal, Brazil. The new species resembles to Clausidium senegalense Humes, 1957 and Clausidium vancouverense (Haddon, 1912) in the armature of P2-P5 of the female, and shares with Clausidium senegalense similar segmentation and armature of the antenna and maxilla of the female. Nevertheless, it can be easily distinguished from its congeners by the unique characteristics observed in the antenna, maxilliped and first leg of males, as well as by the anal somite, maxillule and maxilliped of the females. This new species extends the group distribution to the Southwest Atlantic and represents the first record of the genus in Brazil. A key for the identification of the species based on females of Clausidium is provided.

Gastrotricha: a marine sister for a freshwater puzzle.

BACKGROUND: Within an evolutionary framework of Gastrotricha Marinellina flagellata and Redudasys fornerise bear special interest, as they are the only Macrodasyida that inhabit freshwater ecosystems. Notwithstanding, these rare animals are poorly known; found only once (Austria and Brazil), they are currently systematised as incertae sedis. Here we report on the rediscovery of Redudasys fornerise, provide an account on morphological novelties and present a hypothesis on its phylogenetic relationship based on molecular data. METHODOLOGY/PRINCIPAL FINDINGS: Specimens were surveyed using DIC microscopy and SEM, and used to obtain the 18 S rRNA gene sequence; molecular data was analyzed cladistically in conjunction with data from 42 additional species belonging to the near complete Macrodasyida taxonomic spectrum. Morphological analysis, while providing new information on taxonomically relevant traits (adhesive tubes, protonephridia and sensorial bristles), failed to detect elements of the male system, thus stressing the parthenogenetic nature of the Brazilian species. Phylogenetic analysis, carried out with ML, MP and Bayesian approaches, yielded topologies with strong nodal support and highly congruent with each other. Among the supported groups is the previously undocumented clade showing the alliance between Redudasys fornerise and Dactylopodola agadasys; other strongly sustained clades include the densely sampled families Thaumastodermatidae and Turbanellidae and most genera. CONCLUSIONS/SIGNIFICANCE: A reconsideration of the morphological traits of Dactylopodola agadasys in light of the new information on Redudasys fornerise makes the alliance between these two taxa very likely. As a result, we create Anandrodasys gen. nov. to contain members of the previously described D. agadasys and erect Redudasyidae fam. nov. to reflect this novel relationship between Anandrodasys and Redudasys. From an ecological perspective, the derived position of Redudasys, which is deeply nested within the Macrodasyida clade, unequivocally demonstrates that invasion of freshwater by gastrotrichs has taken place at least twice, in contrast with the single event hypothesis recently put forward.