82 resultados para PHYLOGENY


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Potamotrygonocestus Brooks & Thorson, 1976 is currently represented by six recognised species of tetraphyllidean cestodes inhabiting Neotropical freshwater stingrays. Potamotrygonid stingrays examined to date have included only a single specimen of Plesiotrygon iwamae. Only one species of tetraphyllidean, Potamotrygonocestus chaoi Marques, Brooks & Araujo, 2003, has been described from this host, and this description was based on limited material. New efforts to document the diversity in this host species resulted in the collection of eight additional specimens of P. iwamae, one of these from the upper Rio Solimoes, at Sao Paulo de Olivenca Amazonas during September, 2003, and seven from the Baia do Marajo, Para, during November, 2003. The specimen from the upper Solimoees was found to be infected with P. chaoi. Voucher material from this stingray was used for the redescription of this cestode, which is characterized by strobila 8.78-22.83 mm long and a great number of proglottides, 58-93; the new material provided strobilar length and proglottis counts for complete worms. Potamotrygonocestus marajoara n. sp. is the second species of this genus reported from Plesiotrygon iwamae, although it appears to be restricted to the lower Amazon. This new species resembles P. chaoi in possessing filitriches and blade-like spinitriches on the scolex, cephalic peduncle and cirrus, but differs from other species of the genus in the number of testes, which is 44 on average per proglottis, and by having apical sucker measuring 95-175 mu m in length. Additional data on the distribution and morphology of the microtriches and a detailed description of the female reproductive system are also provided in this study.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Results of a cladistic analysis of the suborder Conulariina Miller and Gurley, 1896, a major extinct (Vendian-Triassic) group of scyphozoan cnidarians, are presented. The analysis sought to test whether the three conulariid subfamilies (Conulariinae Walcott, 1886, Paraconulariinae Sinclair, 1952 and Ctenoconulariinae Sinclair, 1952) recognized in the Treatise on Invertebrate Paleontology ( TIP) are monophyletic. A total of 17 morphological characters were scored for 16 ingroup taxa, namely the genera Archaeoconularia, Baccaconularia, Climacoconus, Conularia, Conulariella, Conularina, Ctenoconularia, Eoconularia, Glyptoconularia, Metaconularia, Notoconularia, Paraconularia, Pseudoconularia, Reticulaconularia, Teresconularia and Vendoconularia. The extant medusozoan taxa Cubozoa, Stauromedusae, Coronatae and Semaeostomeae served as outgroups. Unweighted analysisof the data matrix yielded 1057 trees, and successive weighting analysis resulted in one of the 1057 original trees. The ingroup is monophyletic with two autapomorphies: (1) the quadrate geometry of the oral region; and (2) the presence of a mineralized (phosphatic) periderm. Within the ingroup, the clade (Vendoconularia, Teresconularia, Conularina, Eoconularia) is supported by the sinusoidal longitudinal geometry of the transverse ridges, and the much larger clade (Baccaconularia, Glyptoconularia, Metaconularia, Pseudoconularia, Conularia, Ctenoconularia, Archaeoconularia, Notoconularia, Climacoconus, Paraconularia, Reticulaconularia) is supported by the presence of external tubercles, which, however, were lost in the clade (Notoconularia, Climacoconus, Paraconularia, Reticulaconularia). As proposed by Van Iten et al. (2000), the clade (Notoconularia, Climacoconus, Paraconularia, Reticulaconularia) is supported by the termination and alternation of the transverse ribs in the corner sulcus. The previously recognized subfamilies Conulariinae, Paraconulariinae and Ctenoconulariinae were not recovered from this analysis. The diagnostic features of Conulariinae (continuation of the transverse ornament across the corner sulcus and lack of carinae) and Ctenoconulariinae ( presence of carinae) are symplesiomorphic or homoplastic, and Paraconulariinae is polyphyletic. The families Conulariellidae Kiderlen, 1937 and Conulariopsidae Sugiyama, 1942, also recognized in the TIP, are monogeneric, and since they provide no additional phylogenetic information, should be abandoned.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The utility of the female genitalia and associated sclerites (tergite and sternite VIII) in the systematics of the Curculionidae is discussed. Examples from the tribe Entimini (Entiminae) and subtribe Hylobiina (Molytinae: Hylobiini) are given. The female characters prove to be informative for establishing the phylogenetic relationships among genera of Entimini. They are essential in determining species groups within the genus Amiticus Pascoe, Hylobiina.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background and Aims The amount of data collected previously for Velloziaceae neither clarified relationships within the family nor helped determine an appropriate classification, which has led to huge discordance among treatment by different authors. To achieve an acceptable phylogenetic result and understand the evolution and roles of characters in supporting groups, a total evidence analysis was developed which included approx. 20 % of the species and all recognized genera and sections of Velloziaceae, plus outgroups representatives of related families within Pandanales. Methods Analyses were undertaken with 48 species of Velloziaceae, representing all ten genera, with DNA sequences from the atpB-rbcL spacer, trnL-trnF spacer, trnL intron, trnH-psbA spacer, ITS ribosomal DNA spacers and morphology. Key Results Four groups consistently emerge from the analyses. Persistent leaves, two phloem strands, stem cortex divided in three regions and violet tepals support Acanthochlamys as sister to Velloziaceae s. s., which are supported mainly by leaves with marginal bundles, transfusion tracheids and inflorescence without axis. Within Velloziaceae s. s., an African Xerophyta + Talbotia clade is uniquely supported by basal loculicidal capsules; an American clade, Barbacenia s. l. + Barbaceniopsis + Nanuza + Vellozia, is supported by only homoplastic characters. Barbacenia s. l. (Aylthonia + Barbacenia + Burlemarxia + Pleurostima) is supported by a double sheath in leaf vascular bundles and a corona; Barbaceniopsis + Nanuza + Vellozia is not supported by an unambiguous character, but Barbaceniopsis is supported by five characters, including diclinous flowers, Nanuza + Vellozia is supported mainly by horizontal stigma lobes and stem inner cortex cells with secondary walls, and Vellozia alone is supported mainly by pollen in tetrads. Conclusions The results imply recognition of five genera (Acanthochlamys (Xerophyta (Barbacenia (Barbaceniopsis, Vellozia)))), solving the long-standing controversies among recent classifications of the family. They also suggest a Gondwanan origin for Velloziaceae, with a vicariant pattern of distribution.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

A cladistic analysis was applied to test the monophyly of the genus Isoctenus. The data matrix comprised 28 taxa scored for 53 morphological and two behavioural characters. The analysis resulted in two equally parsimonious trees of 89 steps. The strict consensus was used to discuss the relationships of Isoctenus and related Cteninae genera. Ctenopsis Schmidt is synonymized with Isoctenus. Isoctenus foliifer Bertkau, I. strandi Mello-Leitao, I. eupalaestrus Mello-Leitao, I. janeirus (Walckenaer), I. coxalis (Pickard-Cambridge), I. corymbus Polotow, Brescovit & Pellegatti-Franco and I. malabaris Polotow, Brescovit & Ott are maintained in Isoctenus. Four species currently included in Ctenus are transferred to Isoctenus: I. griseolus (Mello-Leitao) comb. nov., I. taperae (Mello-Leitao) comb. nov., I. herteli (Mello-Leitao) comb. nov. and I. minusculus (Keyserling) comb. nov. The following specific names are synonymized: Ctenus sanguineus Walckenaer, C. semiornatus Mello-Leitao and Ctenopsis stellata Schmidt with Isoctenus janeirus (Walckenaer), Ctenus mourei Mello-Leitao with Isoctenus herteli (Mello-Leitao) and Ctenus pauper Mello-Leitao with Isoctenus strandi Mello-Leitao. Isoctenus sigma Schenkel, described from French Guiana, is transferred to Ctenus. Four species are newly described: Isoctenus areia sp. nov. from Paraiba, Brazil, I. charada sp. nov. and I. segredo sp. nov. from Parana, Brazil, and I. ordinario sp. nov. from south and south-eastern Brazil and north-eastern Argentina. Isoctenus latevittatus Caporiacco is considered species inquirenda. Parabatinga gen. nov. is proposed to include Ctenus brevipes Keyserling. The following synonymies are established: Ctenus taeniatus Keyserling, C. tatarandensis Tullgren, C. anisitsi Strand, C. atrivulvus Strand, C. mentor Strand, C. brevipes brevilabris Strand, Isoctenus masculus Mello-Leitao and Ctenus birabeni Mello-Leitao with Parabatinga brevipes (Keyserling) comb. nov. (C) 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155, 583-614.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The Fernando de Noronha Archipelago (Pernambuco State, Brazil), a national marine park, is formed by 21 islands and islets of volcanic origin. An update of the checklist of the benthic cnidarians from some of the archipelago`s reef environments, as well as a study of their corals and calcified hydroids morphometry, was the major goal of this work. Fieldwork was undertaken in February 2005 and in April 2006 and observations were carried out at 13 stations during snorkeling and/or scuba diving up to 30 m deep. Thirty-four species of cnidarians were recorded, of which 17 are new occurrences for the studied area. When added to the species previously listed in the literature, the total number of benthic cnidarians recorded for the Archipelago increases to 57. Stephanocoenia michelini, a new occurrence of zooxanthellate coral, is worthy of mention, as well as the calcified hydroid Millepora braziliensis. Mussismilia hispida tenuisepta showed several variations among its skeletal characters that surpassed the limits of intraspecific morphological variation when compared to those of Mussismilia hispida.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Several species of the genus Rhipsalis (Cactaceae) are extremely important as ornamentals and are endangered in their natural habitat. However, only a few studies have addressed its taxonomy, morphology (including anatomy), phylogeny and evolutionary history. Consequently, the limited knowledge of the genus coupled with the problematic delimitation of species had led to problems in the identification of taxa. In the current work six species of Rhipsalis, R. cereoides, R. elliptica, R. grandiflora, R. paradoxa, R. pentaptera and R. teres were studied to evaluate the relevance of anatomical characters for the taxonomy of the genus. An anatomical characterization of the primary structure of the stem of Rhipsalis is provided highlighting the differences between species. Features of the stem epidermis are found to discriminate best between species and therefore provide clear and useful characters for the separation of species.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Most Neotropical lowland forest taxa occur exclusively on one side of the Andes despite the availability of appropriate habitat on both sides. Almost all molecular phylogenies and phylogenetic analyses of species assemblages (i.e. area cladograms) have supported the hypothesis that Andean uplift during the Late Pliocene created a vicariant barrier affecting lowland lineages in the region. However, a few widespread plant and animal species occurring in lowland forests on both sides of the Andes challenge the generality of this hypothesis. To understand the role of the Andes in the history of such organisms, we reconstructed the phylogeographic history of a widespread Neotropical flycatcher (Mionectes oleagineus) in the context of the other four species in the genus. A molecular phylogeny based on nuclear and mitochondrial sequences unambiguously showed an early basal split between montane and lowland Mionectes. The phylogeographic reconstruction of lowland taxa revealed a complex history, with multiple cases in which geographically proximate populations do not represent sister lineages. Specifically, three populations of M. oleagineus west of the Andes do not comprise a monophyletic clade; instead, each represents an independent lineage with origins east of the Andes. Divergence time estimates suggest that at least two cross-Andean dispersal events post-date Andean uplift.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

A first case of subsociality is reported for the genus Latrodectus. Individuals were found sharing the same web and feeding together. In captivity they showed mutual tolerance and communal feeding. This finding is remarkable for two reasons. First, widow spiders, even compared with other spiders, are famously aggressive and cannibalistic so that social behavior in the genus was unexpected. Second, the genus nests outside the ""Anelosimus + lost colulus"" clade where all the other social theridiids are found.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The sexual system of the symbiotic shrimp Thor amboinensis is described, along with observations on sex ratio and host-use pattern of different populations. We used a comprehensive approach to elucidate the previously unknown sexual system of this shrimp. Dissections, scanning electron microscopy, size-frequency distribution analysis, and laboratory observations demonstrated that T amboinensis is a protandric hermaphrodite: shrimp first mature as males and change into females later in life. Thor amboinensis inhabited the large and structurally heterogeneous sea anemone Stichoclactyla helianthus in large groups (up to 11 individuals) more frequently than expected by chance alone. Groups exhibited no particularly complex social structure and showed male-biased sex ratios more frequently than expected by chance alone. The adult sex ratio was male-biased in the four separate populations studied, one of them being thousands of kilometers apart from the others. This study supports predictions central to theories of resource monopolization and sex allocation. Dissections demonstrated that unusually large males were parasitized by an undescribed species of isopod (family Entoniscidae). Infestation rates were similarly low in both sexes (approximate to 11%-12%). The available information suggests that T. amboinensis uses pure search promiscuity as a mating system. This hypothesis needs to be formally tested with mating behavior observations and field measurements on the movement pattern of both sexes of the species. Further detailed studies on the lifestyle and sexual system of all the species within this genus and the development of a molecular phylogeny are necessary to elucidate the evolutionary history of gender expression in the genus Thor.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Lauromacromia melanica sp. nov. from Conceicao da Barra municipality, Espirito Santo State, Brazil, is described and illustrated based on two males (both in MNRJ n degrees 135). The new species is similar to L. picinguaba differing from it mainly by the absence of pale spots on S3-6 and by the ellipsoid shape of metepisternal pale stripe. A key for males of all species of the genus is provided. A cladistic analysis encompassing 43 external morphological male characters carried out in two distinct procedures, the first with all characters unordered and the second with two or three state characters ordered. The unordered analysis generated only one most-parsimonious tree (66 steps of length, CI = 0.69, RI = 0.62). The hypothesis of monophyly of Lauromacromia is supported and includes three groups, one formed by the Atlantic Forest species (L. melanica sp. nov. + L. picinguaba), and another by the Cerrado species (L. flaviae + (L. bedei + L. luismoojeni)), and L. dubitalis, positioned in polytomy with these two groups. The ordered analysis also generated only one most-parsimonious tree (68 steps of length, CI = 0.70, RI = 0.67), which maintained the monophyly of Lauromacromia but L. dubitalis positioned basally as sister-group to the Atlantic Forest + Cerrado species groups. The geographic distribution of Lauromacromia is updated with a new record of L. luismoojeni based on one adult male (Brazil: Mato Grosso do Sul State) and probable first Brazilian records for L. dubitalis (Amazonas and Para States) based on two larvae. A vicariance hypothesis is proposed to explain spatial evolution of Lauromacromia, and based on current biogeographical classifications we consider Gomphomacromia and Rialla apart from Neotropical biota. Some aspects of biology and ecology of Lauromacromia are also discussed.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Xenomorellia Malloch, a subgenus of Morellia Robineau-Desvoidy, is revised to include two new species, Morellia (Xenomorellia) inca Nihei and Carvalho sp. nov. from South America, and M. (X.) maia Carvalho and Nihei sp. nov. from Costa Rica and Mexico. Diagnoses for M. (X.) holti (Malloch) and M. (X.) montanhesa (Albuquerque) are provided, as well as an identification key to the four species of the subgenus. A cladistic analysis was performed to test the monophyly of Xenomorellia and to recover the phylogenetic relationships among its species. Tree searches resulted in one single most-parsimonious cladogram, wherein the monophyly of Xenomorellia is supported, as well as a sister-group relationship with the Neotropical subgenus Trichomorellia Stein. Xenomorellia was divided into two clades: one with Caribbean-Andean species (maia + inca), and another with species from southeastern South America (holti + montanhesa).

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Flies of the tribe Muscini (Diptera, Muscidae) are worldwide in distribution and are represented by some 350 species in 18 genera. The present study provides an identification key and diagnoses for all the genera of world Muscini: Biopyrellia Townsend, Curranosia Paterson, Dasyphora Robineau-Desvoidy, Deltotus Seguy, Hennigmyia Peris, Mesembrina Meigen, Mitroplatia Enderlein, Morellia Robineau-Desvoidy, Musca Linnaeus, Myiophaea Enderlein, Neomyia Walker, Neorypellia Pont, Polietes Rondani, Polietina Schnabl & Dziedzicki, Pyrellia Robineau-Desvoidy, Pyrellina Malloch, Sarcopromusca Townsend, Ziminellia Nihei & de Carvalho. Most infrageneric taxa are also represented, namely, the sub-genera of Dasyphora and Morellia. Comments on phylogeny support (whenever pertinent) and the major references containing revisions and regional identification keys to species are provided for each genus and subgenus.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

ORF 31 is a unique baculovirus gene in the genome of Anticarsia gemmatalis multiple nucleopolyhedrovirus isolate 2D (AgMNPV-2D). It encodes a putative polypeptide of 369 aa homologous to poly (ADP-ribose) polymerase (PARP) found in the genomes of several organisms. Moreover, we found a phylogenetic association with Group I PARP proteins and a 3D homology model of its conserved PARP C-terminal catalytic domain indicating that had almost an exact spatial superimposition of < 1 angstrom with other PARP available structures. The 5` end of ORF 31 mRNA was located at the first nucleotide of a CATT motif at position -27. Using real-time PCR we detected transcripts at 3 h post-infection (p.i.) increasing until 24 h p.i., which coincides with the onset of DNA replication, suggestive of a possible role in DNA metabolism.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Dengue virus type 4 (DENV-4) circulates in tropical and subtropical countries from Asia and the Americas. Despite the importance of dengue virus distribution, little is known about the worldwide viral spread. Following a Bayesian phylogenetic approach we inferred the evolutionary history of 310 isolates sampled from 37 countries during the time period 1956-2008 and the spreading dynamics for genotypes I and II. The region (tropical rainforest biome) comprised by Malaysia-Thailand was the most likely ancestral area from which the serotype has originated and spread. Interestingly, cross-correlation analysis on demographic time series with the Asian sequences showed a statistically significant negative correlation that could be suggestive of competition among genotypes within the same serotype. (C) 2011 Elsevier B.V. All rights reserved.