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Poor taxonomic sampling undermines nomenclatural stability: A reply to Roxo et al. (2019)
No full textReis, Roberto E., Britski, Heraldo A., Britto, Marcelo R., Buckup, Paulo A., Calegari, Bárbara B., Camelier, Priscila, Delapieve, Maria Laura S., Langeani, Francisco, Lehmann, Pablo, Lucinda, Paulo H. F., Marinho, Manoela, Martins, Fernanda O., Menezes, Naércio A., Moreira, Cristiano R., De Pinna, Mário C. C., Pavanelli, Carla S., Rapp Py- Daniel, Lucia H., Sousa, Leandro M. (2019): Poor taxonomic sampling undermines nomenclatural stability: A reply to Roxo et al. (2019). Zootaxa 4701 (5): 497-500, DOI: https://doi.org/10.11646/zootaxa.4701.5.1
Revisão taxonômica de Physopyxis Cope, 1871 (Siluriformes, Doradidae) com descrição de duas novas espécies
Get PDFPhysopyxis lyra foi originalmente descrita com base em apenas um exemplar que possuia algumas características muito peculiares. Nesse trabalho, apresento análise de um maior número de exemplares, ampliando a caracterização da espécie e descrevendo duas novas espécies com base em material já depositado em coleções e em novas coletas. Physopyxis lyra é caracterizado por possuir um processo coracóide mais largo que as demais espécies, com as extremidades voltadas para fora, além de possuir placas laterais com apenas uma fileira de espinhos. Physopyxis sp. 1 possui processo coracóide estreito e ligeiramente convergente nas extremidades, com mais de uma fileira de espinhos ao longo das placas laterais. Physopyxis sp. 2 é uma espécie menos robusta, caracterizada por possuir uma linha lateral incompleta com placas pouco desenvolvidas e a presença de uma fileira de espinhos no dorso dos exemplares, formada pela extremidade dos espinhos neurais das vértebras. A distribuição geográfica do gênero, muito pouco conhecida até então, é bastante ampliada, abrangendo diferentes drenagens da bacia amazônica e do Essequibo
Sistemática de Baryancistrus Rapp Py-Daniel, 1989 (Loricariidae: Hypostominae)
Get PDFThe main objectives of the present thesis were to provide a taxonomic review of the genus Baryancistrus, to assess the phylogenetic relationships within the genus, to check its monophyly and to understand the phylogenetic position of the genus within the tribe Ancistrini. The current species included in Baryancistrus were revised based on examination of type material, topotypes, specimens deposited in several fish collections and original descriptions. A phylogenetic hypothesis is proposed for the relationships of the genera of Ancistrini and for the species of Baryancistrus based on 192 characters of 110 terminal taxa. Four of the six species already proposed for the genus were accepted plus the recognition of more 10 new species. An identification key is presented for all species recognized in the genus after the taxonomic revision. Baryancistrus was restricted to the clear-water rivers of the Amazon basin that drain the Guiana and Brazilian Shields. Parsimony analyses resulted in 48 equally most parsimonious trees with 1,704 steps, consistency index of 0.16 and retention index of 0.67; strict-consensus tree was rooted in Rhinelepis strigosa. Baryancistrus were recovered as a natural group, excluding the ones from rio Orinoco basin, in Venezuela. Monophyly of Baryancistrus was supported by 12 non-exclusive synapomorphies, and the most relevant are the thick and round condyle of the quadrate for articulation with the angulo-articular, the presence of a deep depression on the posterior tip of the opercle, elongate maxillary and the presence of seven to eigth infraorbitals. The 14 species of the genus were grouped as (Baryancistrus sp. “membrana” (Baryancistrus sp. “Jari” ((Baryancistrus sp. “Trombetas” (B. longipinnis, B. niveatus)) ((Baryancistrus sp. “jolie” (Baryancistrus sp. “Tapajos”, B. xanthellus))) ((B. chrysolomus (Baryancistrus sp. “Teles Pires”, Baryancistrus sp. “Porteira”)) ((Baryancistrus sp. “bola branca” (Baryancistrus sp. “Araguaia”, Baryancistrus sp. “Culuene”))))), comprising the sister-group of the remaining Ancistrini with hypertrophied membrane posterior to the last dorsal fin ray. Relationships of the genera within Ancistrini are discussed with the proposition of revalidation of previously synonymized genera and new taxonomic arrangements.Os principais objetivos da presente tese foram fornecer uma revisão taxonômica de Baryancistrus, avaliar as relações filogenéticas dentro do gênero, verificar seu monofiletismo e entender a posição filogenética do gênero dentro da tribo Ancistrini. As atuais espécies incluídas em Baryancistrus foram revisadas com base no exame do material tipo, topótipos, espécimes depositados em várias coleções de peixes e descrições originais. Uma hipótese de relações filogenética entre os gêneros de Ancistrini e entre as espécies de Baryancistrus é apresentada com base em 192 caracteres de 110 táxons terminais. Quatro das seis espécies já propostas para o gênero foram aceitas, mais o reconhecimento de mais 10 espécies novas. Uma chave de identificação é apresentada para todas as espécies reconhecidas no gênero após a revisão taxonômica. Baryancistrus ficou restrito aos rios de águas claras oriundos da bacia Amazônica brasileira que drenam os escudos da Guiana e do Brasil. A análise de parcimônia resultou em 48 árvores igualmente parcimoniosas, com 1.704 passos, índice de consistência 0,16 e índice de retenção 0,67; a árvore de consenso estrito foi enraizada em Rhinelepis strigosa. Baryancistrus foi recuperado como um grupo natural, quando excluindo as espécies descritas anteriormente para o gênero, oriundas da bacia do rio Orinoco, na Venezuela. O monofiletismo de Baryancistrus foi suportado por 12 sinapomorfias não-exclusivas, e as mais relevantes são, o côndilo de articulação do quadrado com o ângulo-articular grosso e redondo, a presença de uma fóvea profunda na extremidade posterior do opérculo, o maxilar muito alongado, e a presença de sete a oito infraorbitais. As 14 espécies do gênero foram agrupadas como: (Baryancistrus sp. “membrana” (Baryancistrus sp. “Jari” ((Baryancistrus sp. “Trombetas” (B. longipinnis, B. niveatus)) ((Baryancistrus sp. “jolie” (Baryancistrus sp. “Tapajos”, B. xanthellus))) ((B. chrysolomus (Baryancistrus sp. “Teles Pires”, Baryancistrus sp. “Porteira”)) ((Baryancistrus sp. “bola branca” (Baryancistrus sp. “Araguaia”, Baryancistrus sp. “Culuene”))))), compreendendo o grupo-irmão dos demais Ancistrini que apresentam membrana hipertrofiada posterior ao último raio da nadadeira dorsal. Os relacionamentos dos gêneros dentro de Ancistrini são discutidos com a proposta de revalidação de gêneros previamente sinonimizados e novos arranjos taxonômicos
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Phylogeny of the neotropical armored catfishes of the subfamily Loricariinae (Siluriformes: Loricariidae)
No full textEvidence for the monophyly of Loricariinae is presented using phylogenetic analysis (maximum parsimony in PAUP*) of osteological and external morghological characters. The two different analyses used, with the characters unordered and the characters partly ordered, produced the same levels of relationship among the ingroup taxa, displaying similar support (similar values of decay index and bootstrap). The analyses showed differences in the Loricariinae sister group. In the unordered analysis, the sistes group of the Loricariinae is a clade formed by representatives of Hypostominae, Ancistrinae and Hypoptopomatinae. In the ordered analysis, Neoplecostomus came out as the sister group of Loricariinae. Loricariinae is diagnosed by a large set of synapomorphies under both data sets. Loricariinae is subdivided in two large clades, Loricariini Bonaparte, 1831 and Harttiini Boeseman, 1971, which basically comprise the genera originally assigned. Loricariini comprises two subclades here named after already available taxa, Hemiodontichthyina (Isbrucker, 1979) and Planiloricariina (Isbrucker, 1979, 1980), plus the genera Loricaria, Spatuloricaria and the non-monophyletic Rineloricaria. Harttiini comprises two subclades, Farlowellina (Fowler, 1958) and Harttiina (Boeseman, 1971), plus the genus Sturisomatichthys. In Planiloricariina, Crossoloricaria came out non-monophyletic, and Crossoloricaria and Apistoloricaria are synonymized to Rhadinoloricaria, since these taxa are not supported separately, but as a clade. All taxa inside Loricariinae are diagnosed phylogenetically. The phylogenetic results are discussed under the current systematics for the group. Taxa not available for the analyses were tentatively placed within the phylogenetic hypothesis proposed. New systematic accounts are provided. The co-occurrence of extreme sets of apomorphies is discussed. Due to the positive correlation between sex dimorphic traits and monophyletic groups, a hypothesis on origin of dimorphic traits in Loricariinae is inferred.This item was digitized from a paper original and/or a microfilm copy. If you need higher-resolution images for any content in this item, please contact us at [email protected] file replaced with corrected file November 2023
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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