The Entire Mitochondrial Genome of Macrophthalmus abbreviatus Reveals Insights into the Phylogeny and Gene Rearrangements of Brachyura.

Brachyuran crabs comprise the most species-rich clades among extant Decapoda and are divided into several major superfamilies. However, the phylogeny of Brachyuran remains controversial, comprehensive analysis of the overall phylogeny is still lacking. Complete mitochondrial genome (mitogenome) can indicate phylogenetic relationships, as well as useful information for gene rearrangement mechanisms and molecular evolution. In this study, we firstly sequenced and annotated the complete mitogenome of Macrophthalmus abbreviatus (Brachyura; Macrophthalmidae). The mitogenome length of M. abbreviatus is 16,322 bp, containing the entire set of 37 genes and a control region typically observed in Brachyuran mitogenomes. The genome composition of M. abbreviatus was highly A+T biased 76.3% showing positive AT-skew (0.033) and negative GC-skew (- 0.351). In M. abbreviatus mitogenome, most tRNA genes were folded into the clover-leaf secondary structure except trnH, trnS1 and trnC, which was similar to the other species in Macrophthalmidae. Phylogenetic analysis showed that all families form a monophyletic, and Varunidae and Macrophthalmidae clustered into a monophyletic clade as sister groups. Comparative analyses of rearrangement among Brachyura revealed that Varunidae (Grapsoidea) and Macrophthalmidae (Ocypodoidea) had the same gene order, which reinforced the result of phylogeny. The combined results of two aspects revealed that the polyphyly of Ocypodoidea and Grapsoidea were well supported. In general, the results obtained in this research will contribute to further studies on molecular based for the classification and gene rearrangements of Macrophthalmidae or even Brachyura.

Gene rearrangements in the mitochondrial genome of Chiromantes eulimene (Brachyura: Sesarmidae) and phylogenetic implications for Brachyura.

Complete mitochondrial genome (mitogenome) provides important information for better understanding of gene rearrangement, molecular evolution and phylogenetic analysis. Here we determined the complete mitogenome sequence of Chiromantes eulimene (Brachyura: Sesarmidae) for the first time. The total length is 15,894 bp and includes 13 protein-coding genes (PCGs), 22 transfer RNAs, two ribosomal RNAs, as well as a putative control region. The genome composition is highly A + T biased (75.5%), and exhibits a negative AT-skew (-0.017) and GC-skew (-0.206). All of the 13 PCGs are initiated by the start codon ATN, with an exception (GTG) in ND1. The typical stop codon (TAA or TAG) is detected in ten PCGs, whereas the remaining three PCGs (COI, COII and Cyt b) terminate by an incomplete T. The gene order in C. eulimene mitogenome was rearranged compared with that of the ancestor of Decapoda. The gene order of F-ND5-H changed to H-F-ND5. Like other sesarmid crabs, the I-Q-M gene cluster in the pancrustacean ground pattern became Q-I-M order in C. eulimene genome. Tandem duplication-random loss model and slipped-strand mispairing mechanism are determined as most likely to explain the observed gene rearrangements. Phylogenetic analysis places all Sesarmidae species into one group. Almost all families except Xanthidae, Gecarcinidae and Homolidae form a monophyletic clade and the polyphyly of Eriphioidea, Ocypodoidea and Grapsoidea is well supported. These results will help to better understand the gene rearrangements and evolutionary position of C. eulimene and lay a foundation for further phylogenetic studies of Brachyura.

The complete mitochondrial genome of Calappa bilineata: The first representative from the family Calappidae and its phylogenetic position within Brachyura.

In this study, we determined the complete mitogenome sequence of Calappa bilineata, which is the first mitogenome of Calappidae up to now. The total length is 15,606 bp and includes 13 protein-coding genes, 22 transfer RNAs, two ribosomal RNAs and one control region. The genome composition is highly A + T biased (68.7%), and exhibits a negative AT-skew (-0.010) and GC-skew (-0.267). As with other invertebrate mitogenomes, the PCGs start with the standard ATN and stop with the standard TAN codons or incomplete T. Phylogenetic analysis showed that C. bilineata was most closely related to Matuta planipes (Matutidae), and these two species formed a sister clade, constituting a Calappoidea group and forming a sister clade with part of Eriphioidea. The existence of the polyphyletic families raised doubts over the traditional classification system. These results will help to better understand the features of the C. bilineata mitogenome and lay foundation for further evolutionary relationships within Brachyura.

A class B scavenger receptor mediates antimicrobial peptide secretion and phagocytosis in Chinese mitten crab (Eriocheir sinensis).

Scavenger receptors (SRs) are pattern recognition receptors (PRRs) vital for innate immunity. As well as their importance in immune recognition, microbe phagocytosis, and the clearance of modified endogenous molecules, they also activate downstream immune responses as co-receptors. In the current study, we identified a class B scavenger receptor in Eriocheir sinensis (EsSR-B2). The full-length gene is 2,517 bp and encodes a 517 amino acid polypeptide. EsSR-B2 is expressed widely in all tested tissues and is induced by microbial stimulation. Recombinant EsSR-B2 binds to bacteria and pathogen-associated molecular patterns in vitro. Upon knockdown of EsSR-B2 and bacterial challenge with Staphylococcus aureus or Vibrio parahaemolyticus, phagocytosis rates in hemocytes are decreased. Moreover, the expression of several antimicrobial peptides (AMPs) in response to distinct microorganism stimulation is decreased following EsSR-B2 silencing. Thus, EsSR-B2 is a PRR that protects E. sinensis against invading pathogens by promoting phagocytosis and enhancing AMP expression.

ORDER within the chaos: Insights into phylogenetic relationships within the Anomura (Crustacea: Decapoda) from mitochondrial sequences and gene order rearrangements.

The infraorder Anomura consists of a morphologically and ecologically heterogeneous group of decapod crustaceans, and has attracted interest from taxonomists for decades attempting to find some order out of the seemingly chaotic diversity within the group. Species-level diversity within the Anomura runs the gamut from the "hairy" spindly-legged yeti crab found in deep-sea hydrothermal vent environments to the largest known terrestrial invertebrate, the robust coconut or robber crab. Owing to a well-developed capacity for parallel evolution, as evidenced by the occurrence of multiple independent carcinization events, Anomura has long tested the patience and skill of both taxonomists attempting to find order, and phylogeneticists trying to establish stable hypotheses of evolutionary inter-relationships. In this study, we performed genome skimming to recover the mitogenome sequences of 12 anomuran species including the world's largest extant invertebrate, the robber crab (Birgus latro), thereby over doubling these resources for this group, together with 8 new brachyuran mitogenomes. Maximum-likelihood (ML) and Bayesian-inferred (BI) phylogenetic reconstructions based on amino acid sequences from mitogenome protein-coding genes provided strong support for the monophyly of the Anomura and Brachyura and their sister relationship, consistent with previous studies. The majority of relationships within families were supported and were largely consistent with current taxonomic classifications, whereas many relationships at higher taxonomic levels were unresolved. Nevertheless, we have strong support for a polyphyletic Paguroidea and recovered a well-supported clade of a subset of paguroids (Diogenidae + Coenobitidae) basal to all other anomurans, though this requires further testing with greater taxonomic sampling. We also introduce a new feature to the MitoPhAST bioinformatics pipeline (https://github.com/mht85/MitoPhAST) that enables the extraction of mitochondrial gene order (MGO) information directly from GenBank files and clusters groups based on common MGOs. Using this tool, we compared MGOs across the Anomura and Brachyura, identifying Anomura as a taxonomic "hot spot" with high variability in MGOs among congeneric species from multiple families while noting the broad association of highly-rearranged MGOs with several anomuran lineages inhabiting extreme niches. We also demonstrate the value of MGOs as a source of novel synapomorphies for independently reinforcing tree-based relationships and for shedding light on relationships among challenging groups such as the Aegloidea and Lomisoidea that were unresolved in phylogenetic reconstructions. Overall, this study contributes a substantial amount of new genetic material for Anomura and attempts to further resolve anomuran evolutionary relationships where possible based on a combination of sequence and MGO information. The new feature in MitoPhAST adds to the relatively limited number of bioinformatics tools available for MGO analyses, which can be utilized widely across animal groups.

Molecular Characterization and Expression Profiles of Sp-uchl3 and Sp-uchl5 during Gonad Development of Scylla paramamosain.

Ubiquitin C-terminal hydrolases (UCHLs) are a subset of deubiquitinating enzymes, and are involved in numerous physiological processes. However, the role of UCHLs during gonad development has not been studied in crustaceans. In this study, we have first cloned and analyzed expression profiling of Sp-uchl3 and Sp-uchl5 genes from mud crab Scylla paramamosain. The full-length cDNA of Sp-uchl3 is of 1804 bp. Its expression level in the ovary was significantly higher than in other tissues (p < 0.01), and during gonadal development, its expression in both O1 and O5 stages was significantly higher than in the other three stages of ovaries (p < 0.05), while in T3 it was higher than in the former two stages of testes (p < 0.05). Meanwhile, the full-length cDNA of Sp-UCHL5 is 1217 bp. The expression level in the ovary was significantly higher than in other tissues (p < 0.01). Its expression in ovaries was higher than in testes during gonadal development (p < 0.05). The expression level in the O5 stage was the highest, followed by the O3 stage in ovarian development, and with no significant difference in the testis development (p > 0.05). These results provide basic data showing the role of Sp-UCHL3 and Sp-UCHL5 in the gonad development of the crab.

A chymotrypsin-like serine protease from Portunus trituberculatus involved in pathogen recognition and AMP synthesis but not required for prophenoloxidase activation.

Clip domain serine proteases (clip-SPs) play critical roles in various immune responses in arthropods, such as hemolymph coagulation, antimicrobial peptide (AMP) synthesis, cell adhesion and melanization. In the present study, we report the molecular and functional characterization of a clip domain serine protease (PtcSP2) from the swimming crab Portunus trituberculatus. The N-terminal clip domain and the C-terminal SP-like domain of PtcSP2 were expressed in Escherichia coli system, and assayed for their activities. Sequence similarity and phylogenetic analysis revealed that PtcSP2 may belong to the chymotrypsin family, which was confirmed by protease activity assay of the recombinant SP-like domain. The clip domain of PtcSP2 exhibited strong antibacterial activity and microbial-binding activity, suggesting the potential role in immune defense and recognition. Knockdown of PtcSP2 by RNA interference could significantly reduce PtcSP2 transcript levels, but neither decrease the total phenoloxidase (PO) activity in crab nor significantly alter the expression levels of serine protease inhibitors PtPLC and PtSerpin. These results indicate that PtcSP2 is not involved in the proPO system. However, suppression of PtcSP2 led to a significant change in the expression of AMP genes PtALFs and PtCrustin but not PtALF5. All these findings suggest that PtcSP2 is a multifunctional chymotrypsin-like serine protease and may participate in crab innate immunity by its antibacterial activity, immune recognition or regulation of AMP expression.

Morphological differences between Stenocionops furcatus (Olivier, 1791) and S. coelatus (A. Milne-Edwards, 1878) (Crustacea, Decapoda, Brachyura, Majoidea).

Stenocionops furcatus (Olivier, 1791) and S. coelatus (A. Milne-Edwards, 1878) have been treated either as subspecies or as species in their own right, but never as each other's synonyms. Compared to S. coelatus, S. furcatus has been regarded as having smoother dorsal surface carapace, shorter rostral spines, straighter and less divergent rostrum. and smaller interorbital width. These morphological differences between the two species, however, can be attributed to changes over ontogeny and, therefore, cannot be used as distinguishing characters. Adults of S. coelatus and S. furcatus can, however, be safely separated from each other by the presence in S. coelatus of a strong crenation on the anterior margin of the male sterno-abdominal cavity, which is absent in S. furcatus. A lectotype for S. coelatus is designated. The synonymy between S. furcatus, Cancer cornudo Herbst, 1804, and Chorinus armatus Randall, 1839, is confirmed based on the holotypes of the latter two species.

Adenosine monophosphate-activated protein kinase from the mud crab, Scylla paramamosain: cDNA cloning and profiles under cold stress.

Adenosine monophosphate-activated protein kinase (AMPK), an important energy sensor, is crucial for organism survival under adverse conditions. In this study, the roles of this gene under cold stress in a warm-water mud crab, Scylla paramamosain was investigated. The full-length cDNA (SpAMPK) was 1884 bp and its open reading frame of 1566 bp was isolated and characterized. The expressions of SpAMPK detected by quantitative real-time PCR (qRT-PCR) in various tissues revealed that the highest expression was in the hepatopancreas. The profiles of SpAMPK gene in the hepatopancreas, chela muscle and gill were detected when the subadult crabs were exposed to the four temperature conditions of 10, 15, 20 and 25°C. The results showed that the expression patterns of SpAMPK mRNA in the three tissues were significantly higher when crabs were exposed to 15°C than the other three temperature treatments, while at 10°C treatment, the SpAMPK mRNA was lowest among the four temperature treatments. These findings suggested that the high expression of SpAMPK mRNA might initiate ATP-producing pathways to generate energy to cope with cold stress at 15°C treatment, which was slightly below the range of optimum temperatures; while treatment at 10°C, far lower than optima, the low expression of SpAMPK mRNA could reduce the energy expenditure and thus induce the crabs into cold anesthesia. The results of SpAMPK in this study might contribute to the understanding of the molecular mechanism of acclimation to cold hardiness in S. paramamosain.

Carcinoplax fasciata, a new species of deep-water goneplacid crab from southwestern India (Crustacea: Decapoda: Brachyura: Goneplacoidea).

A new species of Carcinoplax H. Milne Edwards, 1852 (family Goneplacidae) is described from southern India. Carcinoplax fasciata n. sp. is closest to C. specularis Rathbun, 1914, but can be distinguished by its different coloration in life as well as structures of the carapace surface, anterolateral armature, supraorbital margin, chela and male first gonopod.

Report of leucine-rich repeats (LRRs) from Scylla serrata: Ontogeny, molecular cloning, characterization and expression analysis following ligand stimulation, and upon bacterial and viral infections.

Leucine-rich repeat (LRR) proteins are present in all living organisms, and their participation in signal transduction and defense mechanisms has been elucidated in humans and mosquitoes. LRRs possibly involve in protein-protein interactions also and show differential expression pattern upon challenge with pathogens. In the present study, a new LRR gene was identified in mud crab, Scylla serrata. LRR gene mRNA levels in different developmental stages and various tissues of S. serrata were analysed. Further, the response of the gene against different ligands, Gram-negative bacterium, and white spot syndrome virus (WSSV) was investigated in vitro and in vivo. Full-length cDNA sequence of S. serrata LRR (SsLRR) was found to be 2290 nucleotide long with an open reading frame of 1893bp. SsLRR encodes for a protein containing 630 deduced amino acids with 17 conserved LRR domains and exhibits significant similarity with crustacean LRRs so that these could be clustered into a branch in the phylogenetic tree. SsLRR mRNA transcripts were detected in all the developmental stages (egg, Zoea1-5, megalopa and crab instar), haemocytes and various tissues such as, stomach, gill, muscle, hepatopancreas, hematopoietic organ, heart, epithelial layer and testis by reverse-transcriptase PCR. SsLRR transcripts in cultured haemocytes showed a 2-fold increase in expression at 1.5 and 12h upon Poly I:C induction. WSSV challenge resulted in significant early up-regulation at 3h in-vitro and late up-regulation at 72h in-vivo. Peptidoglycan (PGN)-induction resulted in marginal up-regulation of SsLRR at timepoints, 6, 12 and 24h (fold change below 1.5) and no significant change in the expression at early timepoints. LPS-stimulation, on the other hand, showed either down-regulation or normal level of expression at all timepoints. However, a delayed 5-fold up-regulation was observed in vivo against Vibrio parahaemolyticus infection at 72hpi. The constitutive expression of the LRR gene in all the early life-stages, and its response to various ligands and to viral challenge suggest the possible role of the LRR in immune defense in mud crab. The result provides additional information which would help in future studies in understanding the innate immune pathways in crustaceans.

Macrofauna bentónica de las playas de arena del Área de Conservación Osa, Puntarenas, Pacífico Sur de Costa Rica / Benthic macrofauna found in Sandy beaches from Osa Conservation Area, Puntarenas, Southern Pacific coast of Costa Rica

Resumen Se describe la diversidad y composición de especies las playas de arena del Pacífico Sur de Costa Rica. En las playas de arena de la región, se colectó individuos de la infauna por medio de barrenos. Para la zona de entre mareas arenosa el número de especies estrictamente marina varió de 5 a 13 taxones, número que es intermedio con los reportados previamente para estos ambientes en Costa Rica. En la zonas de arena, el supralitoral lo dominó el isópodo Cirolana salvadorensis, mientras nereidos y un gusano de la Familia Pisionidae dominaron en el infralitoral. Otros organismos encontrados en las playas fueron cangrejos del género Uca, cangrejos anomuros (Emerita), galletas de mar (Mellita longifissa) y varios grupos de poliquetos tubícolas permanentes o temporales de la familias Onuphidae, Spionidae, Magelonidae y Glyceridae. Las playas mostraron variación en su fauna atribuible en ciertos casos a la exposición al oleaje, teniendo menos fauna en las playas más reflectivas. Se mencionan acitivades humanas que pueden explicar la baja riqueza de especies encontrada en algunas de las playas analizadas.

Abstract The diversity and species composition of the intertidal sandy beaches in the southern Pacific coast of Costa Rica were studied by means of cores collected along perpendicular transects to the beaches. The numbers of strictly marine species varied between 5 to 13 taxa, representing an intermediate value compared to those previously reported for these environments in Costa Rica. The isopod Cirolana salvadorensis was the dominant species in the supralittoral zone, whereas polychaete worms belonging to the families Nereididae and Pisionidae dominated the low intertidal zone. Others organisms collected in the beaches were the crabs of the genus Uca, anomurans crabs (Emerita), sand dollars (Mellita longifissa) and several taxa of polychaete tubeworms, such as the Onuphidae, Spionidae, Magelonidae, and Glyceridae. The high faunal difference among the sites is possibly explained by their exposure to the wave energy, with fewer individuals in the more reflective beaches. In addition, human activities might also be responsible for the low infaunal diversity found in some of these beaches. This is the first effort to describe the benthonic fauna of beaches from this area. Rev. Biol. Trop. 63 (Suppl. 1): 273-285. Epub 2015 April 01.

Population biology and color patterns of the blue land crab, Cardisoma guanhumi (Latreille 1828) (Crustacea: Gecarcinidae) in the Northeastern Brazil / Biologia Populacional e padrões de coloração do caranguejo terrestre, Cardisoma guanhumi (Latreille 1828) (Crustacea: Gecarcinidae) no Nordeste do Brasil

The objective of this study was to analyze the population biology and color patterns of Cardisoma guanhumi Latreille, 1828 in a mangrove area in Natal, Rio Grande do Norte, Brazil. Crabs were collected monthly between February 2010 and January 2012 and totaled 1,837 individuals. Sex ratios were similar between males and females in the first year and differed in the second. Sex ratios by size class differed statistically in the extremes of the distribution, with an abundance of males in the large size classes. There was no difference (p > 0.05) in carapace width between males and females in the first year, but in the second year, males were larger than females (p = 0.003), showing the importance of considering interannual variation in such studies. Both sexes presented a unimodal distribution. The size of first maturing of the females was 6.00 cm. Asymptotic carapace width for males was 9.4 cm and females for 9.2 cm, using the Wetherall method. There was no defined modal progression, which made the determination of the Von Bertalanffy growth parameter K impossible. Juveniles were found throughout all months of the year, demonstrating that there was no defined period of recruiting, although slightly fewer juveniles were found in the dry season. Four color patterns were observed, the three first patterns were the same for both sexes, while the fourth pattern was observed in females only. The four color patterns identified could be clearly related to the stage of development (size) and sexual maturity of the animal.

O objetivo deste artigo foi analisar a biologia populacional e os padrões de coloração da carapaça de Cardisoma guanhumi Latreille, 1828 em uma área de manguezal em Natal, Rio Grande do Norte, Brasil. Os caranguejos foram coletados mensalmente entre fevereiro de 2010 e janeiro de 2012 e totalizaram 1837 caranguejos. A proporção sexual foi semelhante para machos e fêmeas (1:1) no primeiro ano e diferiu no segundo ano. A proporção sexual por classe de tamanho diferiu estatisticamente nas classes extremas da distribuição, com abundância de machos nas superiores. Não houve diferença (p ≥ 0,05) entre as larguras de carapaça de machos e fêmeas no primeiro ano, porém no segundo os machos foram maiores que as fêmeas (p = 0,003), revelando à importância de se considerar as variações interanuais nestes estudos. Ambos os sexos apresentaram distribuição unimodal. O tamanho de primeira maturação sexual das fêmeas foi 6,00 cm. A largura de carapaça assintótica para machos foi de 9,4 cm e para as fêmeas de 9,2 cm, usando o método Wetherall. Não houve progressão modal definida, o que impossibilitou a determinação do parâmetro de crescimento k de Von Bertalanffy. Foram encontrados juvenis ao longo de todos os meses do ano, mostrando não haver um período de recrutamento definido, embora a abundância de juvenis tenha sido menor na estação seca. Foram observados quatro padrões de coloração, três para ambos os sexos e um quarto padrão observado apenas para as fêmeas. Os quatro padrões de coloração da carapaça estão claramente relacionados ao estágio de desenvolvimento (tamanho) e à maturidade sexual do animal.

Differential habitat use by demographic groups of the redfinger rubble crab Eriphia gonagra (Fabricius, 1781) / Ocupação diferencial do habitat por grupos demográficos do caranguejo de dedos vermelhos Eriphia gonagra (Fabricius, 1781)

The structurally diverse rocky shores along the northern coast of the state of São Paulo, Brazil, support a varied fauna and provide refuges for many organisms. Some of these environments allow for extensive microhabitats, among them the sand reefs formed by the polychaete Phragmatopoma lapidosa, which occupy much of this area. The beauty of the landscape attracts large numbers of tourists, who contribute to the damage to the sand reef colonies, causing an imbalance in the patterns of population distribution and of this ecosystem. We describe the structure and population biology of the redfinger rubble crab Eriphia gonagra, and investigated the differential occupation of the habitat by each demographic category of this species. Crabs were sampled monthly for two consecutive years on the rocky coast of Grande Beach, Ubatuba, São Paulo, during spring low tides. Sampling was carried out over an area of approximately 1200 m2, during two hours on the rock surface and another two hours on the sand reefs. A total of 1407 crabs were collected; 776 on the sand reef (SR) and 631 on the rocky shore (RO). The majority of juvenile crabs inhabited the SR, while adult crabs were equally distributed in both microhabitats. This study showed that the SR is a natural nursery ground for the establishment of the early juvenile stages of E. gonagra, which use the reefs as a refuge and food resource. Many other organisms (mollusks, echinoderms, polychaetes etc.) settle on the reefs, and these areas may be among the most important in maintaining benthic diversity in the region.

Os costões rochosos do litoral norte paulista, devido à sua constituição diversificada, sustentam uma grande diversidade de espécies animais e vegetais, além de proporcionar uma série de abrigos para proteção de muitos organismos. Em alguns destes costões ocorre a formação de microhabitats, entre eles os recifes de areia formadas pelo poliqueta Phragmatopoma lapidosa, que ocupam grande parte desta área. A paisagem diferenciada do local atrai um grande número de turistas, o que contribui para a deterioração das colônias que constituem esse recife, causando um desequilíbrio nos padrões de distribuição das populações desse ecossistema. Este trabalho visou levantar informações sobre a estrutura e dinâmica populacional de Eriphia gonagra, além de investigar uma ocupação diferencial do habitat por diferentes grupos etários deste caranguejo. Os caranguejos foram amostrados mensalmente, durante dois anos consecutivos, no costão rochoso da Praia Grande, Ubatuba, São Paulo, Brasil, em períodos de marés baixas de sizígia. A coleta ativa dos indivíduos foi efetuada em uma área de aproximadamente 1200 m2 por um período de duas horas na superfície rochosa e outras duas horas nos recifes de areia. Foi capturado um total de 1407 indivíduos, sendo 776 no recife de areia (SR) e 631 na superfície rochosa (RO). A maior parte dos jovens habita o recife, enquanto adultos encontram-se igualmente distribuídos nas duas áreas amostradas. Este estudo mostra que os recifes de areia podem ser considerados berçários de suma importância para o estabelecimento dos estágios juvenis de E. gonagra, que utilizam tais locais para proteção e alimentação. Muitos outros organismos (moluscos, equinodermos, poliquetas etc) se estabelecem sobre os recifes, sendo que essas áreas podem estar entre as mais importantes na manutenção da diversidade bêntica na região.

Chemical defense in the red seaweed Plocamium brasiliense: spatial variability and differential action on herbivores / Defesa química na macroalga marinha vermelha Plocamium brasiliense: variabilidade espacial e diferentes ações sobre herbívoros

Species of Plocamium are known as prolific sources of halogenated secondary metabolites exhibiting few explored ecological roles. In this study the crude extracts from specimens of P. brasiliense collected in two distinct places, Enseada do Forno and Praia Rasa, Búzios, Estado do Rio de Janeiro, were evaluated as defense against the sea urchin Lytechinus variegatus and the crab Acanthonyx scutiformis. These specimens produce a similar amount of crude extract and also halogenated monoterpene compound-types, but individuals of P. brasiliense from Praia Rasa exhibit a major compound representing about 59% of the total chemicals. Natural concentrations of the crude extracts obtained from both specimens of P. brasiliense significantly inhibited the herbivory by the sea urchin L. variegatus, but had no significant effect on the feeding by A. scutiformis, a crab commonly associated to chemically defended host. Crude extract from P. brasiliense collected at Praia Rasa was more efficient as defense against L. variegatus than that crude extract from populations of this alga from Enseada do Forno, probably due to presence of a major secondary metabolite. These two studied population live under different environmental conditions, but they are only about 30 Km apart. However, it is impossible to affirm that environmental characteristics (abiotic or biotic) would be responsible for the difference of defensive potential found in the two populations of P. brasiliense studied here. Further genetic studies will be necessary to clarify this question and to explain why populations of a single species living in different but close locations can exhibit distinct chemicals.

Espécies de Plocamium são conhecidas como fontes prolíficas de metabólitos secundários halogenados com significados ecológicos pouco conhecidos. Neste trabalho extratos brutos de espécimes de P. brasiliense coletados em duas localidades distintas, Enseada do Forno e Praia Rasa, Búzios, Estado do Rio de Janeiro, foram avaliados como defesa química contra o ouriço Lytechinus variegatus e o caranguejo Acanthonyx scutiformis. Estes espécimes produzem teores similares de extrato bruto e tipos de substâncias monoterpenos halogenados, mas os indivíduos da Praia Rasa possui um componente majoritário representando 59% do total de metabólitos. Concentrações naturais dos extratos brutos destes espécimes inibiram significativamente o consumo por L. variegatus, mas não causaram qualquer efeito sobre A. scutiformis, um caranguejo comumente associado a P. brasiliense, um hospedeiro quimicamente defendido. O extrato bruto de P. brasiliense coletada na Praia Rasa foi mais eficiente como defesa frente a L. variegatus do que aquele obtido de população desta alga da Enseada do Forno, provavelmente pela presença de uma substância majoritária. Estas duas populações de P. brasiliense estudadas vivem sob diferentes condições ambientais, mas distantes somente cerca de 30 km. Entretanto, é impossível afirmar que características ambientais (abióticas ou bióticas) seriam responsáveis pelas diferenças de potencial defensivo encontrados nestas duas populações de P. brasiliense estudadas. Futuros estudos genéticos são necessários para esclarecer esta questão e para explicar porque populações de uma mesma espécie vivendo em regiões tão próximas, mas ambientalmente distintas, produzem substâncias distintas.

On the identity of Cancer urania Herbst, 1801 (Crustacea: Decapoda: Brachyura: Leucosiidae).

Cancer urania Herbst, 1801, is the type species of the leucosiid genus Coleusia Galil, 2006. Its identity has been a subject of confusion due to various taxonomical and nomenclatural issues. We redescribe the species, discuss its complex history and taxonomy, and a female syntype is designated as the lectotype of the species to clarify any lingering ambiguities concerning the type material of Cancer urania Herbst, 1801.

Local distribution and abundance of Cardisoma guanhumi Latreille, 1928 (Brachyura: Gecarcinidae) in southern Brazil / Distribuição local e abundância de Cardisoma guanhumi Latreille, 1928 (Brachyura: Gecarcinidae) no sul do Brasil

The blue land crab, Cardisoma guanhumi Latreille, 1828 (Brachyura: Gecarcinidae) is officially included in the list of over-exploited species in Brazil, although still abundantly found in the state of Santa Catarina, the southern limit of its distribution. This species was found in forested areas, gardens, and grassy areas, including crabs with carapace width larger than 80mm. The existence of this population with these characteristics is surprising, since there is only one official record of the species in the southern region. The objectives of this study are to estimate the abundance and occupation patterns of C. guanhumi in this region. Correlations with conservation were discussed. The absolute abundance of crabs in the middle of summer activity was established for an area of 100,000 m2. A smaller area was mapped and divided into sampling units for statistical analyses. We distributed approximately 240 crabs in a forested area of about 3,000 m2 and 150 crabs in grassy areas (90,000 m2). The statistical test of Kruskal-Wallis test showed that there are significant differences between the sizes of the openings of the galleries inside the forest and that located in grassy areas. In the forest, the openings tend to be much larger. Burrows were found at a distance of 150 metres from the channel. The number of galleries was higher in the forested area, although the burrows were more densely grouped in grassy areas. Although C. guanhumi seems to be adjusting well to changes caused by human occupation, small forested areas are more conducive to growth and conservation of this species.

O Guaiamum, Cardisoma guanhumi Latreille, 1828 (Brachyura: Gecarcinidae) é uma espécie oficialmente inclusa na lista de espécies sobre-explotadas no Brasil, ainda encontrada em abundância no Estado de Santa Catarina, seu limite austral de distribuição. Esta espécie foi encontrada tanto em áreas florestais quanto em jardins e áreas abertas, sendo comuns caranguejos de grande porte (largura da carapaça > 80mm). A existência dessa população com tais características surpreende, pois há apenas um registro oficial da espécie na região sul. Os objetivos deste estudo é estimar a abundância desta espécie na região, inferir padrões de distribuição relacionados ao tipo de ecossistema e ao tamanho das aberturas de toca. Essas informações foram relacionadas à conservação desta população. A abundância absoluta de caranguejos em atividade no meio do verão foi estabelecida para uma área de 100.000 m2. Uma área menor foi mapeada e dividida em unidades amostrais, utilizadas para análises estatísticas. Contamos aproximadamente 240 caranguejos distribuídos em uma área de floresta de aproximadamente 3.000 m2 e 150 caranguejos em áreas abertas equivalentes a 90.000 m2. O teste estatístico de Kruskal-Wallis evidenciou que há diferenças significativas entre os tamanhos das aberturas das galerias no interior da floresta em relação às localizadas em áreas abertas. Na floresta, as aberturas tendem a ser muito maiores. Foram encontradas tocas a uma distância de 150 metros do canal. O número de galerias foi maior na área florestada, embora as tocas sejam mais densamente agrupadas em áreas abertas. Embora C. guanhumi pareça estar se adaptando bem as mudanças provocadas pela ocupação humana, as pequenas áreas florestadas são mais propícias para o crescimento e a conservação desta espécie.

Expression and function analysis of metallothionein in the testis of Portunus trituberculatus exposed to cadmium.

Metallothioneins (MTs) possess a unique molecular structure that provides metal-binding and redox capabilities. These capabilities include the maintenance of metal equilibria that protect against heavy metals (especially cadmium) and oxidative damage. Past studies have focused on the function of MTs in vertebrates. However, the functions of MTs during spermiogenesis in invertebrates remain unclear. In order to investigate the function of MTs during spermiogenesis in Portunus trituberculatus, we used RT-PCR and RACE to identify two MT complete cDNA sequences in the total RNA from the P. trituberculatus testis. The 450 bp MT-1 cDNA consists of a 77 bp 5' untranslated region, a 196 bp 3' untranslated region, and a 177 bp open reading frame that encodes 58 amino acids including 19 cysteines. The 581 bp MT-2 cDNA consists of 73 bp 5' untranslated region, a 328 bp 3' untranslated region, and a 180 bp open reading frame that encodes 59 amino acids including 18 cysteines. MT-1 and MT-2 of P. trituberculatus more closely resemble invertebrate (especially crab) MT homologues than vertebrate MT homologues as indicated by protein alignment comparisons and phylogenetic tree analysis. MT-1 and MT-2 were detected in the heart, testis, muscle, hepatopancreas, and gill of P. trituberculatus by tissue expression analysis. In addition, MT-1 and MT-2 are present during the entire process of spermiogenesis in P. trituberculatus as indicated by H&E staining and in situ hybridization. MT-1 and MT-2 expression levels significantly increase after cadmium (Cd) exposure as measured by real-time quantitative PCR analysis. Therefore, we suggest that MT-1 and MT-2 perform important functions in spermiogenesis and testis detoxification in P. trituberculatus.

Breeding period in the mangrove crab Goniopsis cruentata (Decapoda: Grapsidae) in Northeast Brazil

The brachyuran crabs are iteroparous species which present a high diversification of reproduction patterns, which may have evolved as a species-specific response to environmental conditions. Tropical species commonly present a year-round reproduction due to stable environment conditions. Goniopsis cruentata is a crab species widely distributed along the Western Atlantic, inhabiting practically every microhabitat in the mangrove ecosystem. The aim of the present study is to determine the breeding period of the crab Goniopsis cruentata in Northeastern Brazil and also to evaluate the influence of water salinity, rainfall and air and water temperature on it. A total of 71 ovigerous females, captured from August-2007 to July-2008, were used to assess the breeding period of this species. It was analyzed by the monthly proportion of ovigerous females. A correlation was applied to verify the influence of the abiotic factors on the breeding period. The present population bred seasonal-continuously with peaks in the dry period, which was not associated with monthly variations of salinity, rainfall and air and water temperatures. Therefore, according to statistical analyses, our hypothesis was refuted. However, breeding was intensified in the dry period, when salinity and temperatures were higher and rainfall was lower. We conclude that, even though breeding is not related to monthly variation of environmental factors, it occurs in periods of higher salinity and temperatures and lower rainfall.

Los cangrejos Brachyura son especies iteróparas, que presentan alta diversificación en los patrones de reproducción, que pueden haber evolucionado como una respuesta específica de la especie a las condiciones ambientales. Las especies tropicales frecuentemente presentan una reproducción en todo el año debido a las condiciones estables del medio. El cangrejo Goniopsis cruentata es una especie ampliamente distribuida en largo del Atlántico occidental, y que habita prácticamente cada micro-hábitat en el ecosistema de manglar. El objetivo del presente estudio fue evaluar el periodo de reproducción del cangrejo G. cruentata en el noreste de Brasil. Un total de 71 hembras ovadas, fueron capturadas entre agosto 2007 y julio 2008, y utilizadas para obtener el periodo de reproducción de esta especie. Nuestra hipótesis es que, ya que las zonas tropicales no presentan gran variación de las temperaturas, las oscilaciones temporales de la salinidad son el principal factor que influye en la actividad reproductiva de G. cruentata. Se analizó el período reproductivo mediante la proporción mensual de hembras ovadas. Una correlación fue aplicada para evaluar la influencia de los factores abióticos limitantes (salinidad, pluviosidad, temperatura del aire y del agua) en la época de crianza. La población se reproduce continuamente con picos estacionales en el período seco, lo que no fue asociado a las variaciones mensuales de salinidad, precipitación y temperatura del aire y del agua. Por lo tanto, nuestra hipótesis fue refutada. Sin embargo, la reproducción se intensificó en el período seco, cuando la salinidad y las temperaturas fueron más altas y la precipitación fue menor. Se concluye que, a pesar de que la reproducción no está relacionada con la variación mensual de los factores ambientales limitantes, ella ocurre en períodos de mayor salinidad y temperatura, y baja precipitación.

Discovery of a new genus and new species of Indo-West Pacific pilumnoidid crab from a semisubmersible oil platform (Crustacea: Brachyura: Pseudozioidea).

A new genus and new species of pseudozioid crab of the family Pilumnoididae is described from a fouling community on a semisubmersible oil platform in Singapore that had been operating in the Timor Sea and South China Sea. Setozius incertus gen. et sp. nov. superficially resembles species of Pilumnus (Pilumnidae, Pilumnoidea) but has male first and second gonopod structures characteristic of the Pseudozioidea. The form of the carapace, male anterior thoracic sternum and male abdomen indicates that it should be classified in the Pilumnoididae. Setozius is the first member of the family to be recorded from the Indo-West Pacific; all other known pilumnoidids occur in the Atlantic and eastern Pacific.