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1.
J Anat ; 237(3): 439-467, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32285471

RESUMEN

The association between lateral-line canals and skull bones in fishes has been the subject of several studies and raised a series of controversies, particularly with regard to the hypothesized role of lateral-line organs (i.e. neuromasts) in osteogenesis and the consequences for hypotheses of homology of the bones associated with lateral-line canals. Polypteridae, a group of freshwater fishes that occupies a key phylogenetic position as the most basal extant lineage of ray-finned fishes (Actinopterygii), provides an interesting model for the study of the relationships between lateral-line canals and skull bones. We describe the development of bones associated with lateral-line canals in the Senegal Bichir, Polypterus senegalus, and use these data to re-address previous hypotheses of homology of skull bones of polypterids. We demonstrate that the lateral-line canals constitute a separate component of the dermatocranium that may interact with a membranodermal component, thereby forming compound bones in the adult. Differences in the interactions between these components determine the characteristics of the development of each independent bone in the skull of adult P. senegalus. Our results shed light on long-standing controversies about the identity of skull bones such as the rostral, preopercle, and sphenotic in Polypteridae, and suggest the presence of an ancestral two-component pattern of formation of bones associated with lateral-line canals in bony fishes. These findings reveal the need to re-address previous hypotheses of homology of bones associated with lateral-line canals in different groups of bony fishes, especially fossil taxa.


Asunto(s)
Peces/anatomía & histología , Sistema de la Línea Lateral/anatomía & histología , Cráneo/anatomía & histología , Animales , Peces/embriología , Sistema de la Línea Lateral/embriología , Osteogénesis/fisiología , Cráneo/embriología
2.
J Fish Biol ; 94(3): 352-373, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30671956

RESUMEN

As part of an ongoing taxonomic revision of the genus Heptapterus from the Laguna dos Patos and Uruguay River drainages and Atlantic coastal streams of southern Brazil and Uruguay, two new species closely related to Heptapterus mustelinus were identified. Both species are endemic to small tributaries of the Uruguay River. The two new species are distinguished from each other and from other species of Heptapterus by arrangement of cephalic and trunk laterosensory systems, number of vertebrae and number of dorsal, pectoral and anal-fin rays. Phylogenetic analyses of mitochondrial DNA (coI and cytb) sequence data further supports distinctiveness of the two new species.


Asunto(s)
Bagres/anatomía & histología , Bagres/clasificación , Filogenia , Animales , Brasil , Bagres/genética , Femenino , Masculino , Ríos , Uruguay
3.
Cladistics ; 30(3): 322-329, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34788970

RESUMEN

Recent commentary by Costello and collaborators on the current state of the global taxonomic enterprise attempts to demonstrate that taxonomy is not in decline as feared by taxonomists, but rather is increasing by virtue of the rate at which new species are formally named. Having supported their views with data that clearly indicate as much, Costello et al. make recommendations to increase the rate of new species descriptions even more. However, their views appear to rely on the perception of species as static and numerically if not historically equivalent entities whose value lie in their roles as "metrics". As such, their one-dimensional portrayal of the discipline, as concerned solely with the creation of new species names, fails to take into account both the conceptual and epistemological foundations of systematics. We refute the end-user view that taxonomy is on the rise simply because more new species are being described compared with earlier decades, and that, by implication, taxonomic practice is a formality whose pace can be streamlined without considerable resources, intellectual or otherwise. Rather, we defend the opposite viewpoint that professional taxonomy is in decline relative to the immediacy of the extinction crisis, and that this decline threatens not just the empirical science of phylogenetic systematics, but also the foundations of comparative biology on which other fields rely. The allocation of space in top-ranked journals to propagate views such as those of Costello et al. lends superficial credence to the unsupportive mindset of many of those in charge of the institutional fate of taxonomy. We emphasize that taxonomy and the description of new species are dependent upon, and only make sense in light of, empirically based classifications that reflect evolutionary history; homology assessments are at the centre of these endeavours, such that the biological sciences cannot afford to have professional taxonomists sacrifice the comparative and historical depth of their hypotheses in order to accelerate new species descriptions.

4.
An Acad Bras Cienc ; 90(2): 1279-1284, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29898095
5.
Zootaxa ; 5297(1): 1-47, 2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37518811

RESUMEN

A new species of Scleronema (Trichomycteridae) is described from the lowlands of three coastal river basins in the Atlantic Forest of the Santa Catarina state, Southern Brazil. Aspects of the anatomy, reproduction, diet, feeding behavior and habitat of the new species are described and discussed in comparison with related taxa. The conservation status of the new species, which currently faces several threats due to environmental impacts on its region of occurrence, is established. Based on characteristics observed in the new species, as well as in most of its congeners, the phylogenetic position and monophyly of Scleronema are discussed and traits considered synapomorphic for the subgenera Plesioscleronema and Scleronema are reviewed. The monophyly of the genus Scleronema is supported by a new synapomorphy. In addition, two new synapomorphies, one of which based on behavior, are suggested for the subgenus Scleronema, justifying the inclusion of the new species. Within the subgenus Scleronema, the new species is assigned to the S. minutum group, which currently includes the majority of species of the genus, due to the presence of synapomorphic traits related to the body shape, maxillary barbel, skin flap of the opercle, caudal and pectoral fins, as well as osteological features of the lower jaw, hyoid arch, and postcranial axial skeleton. The species herein described differs from all its congeners by a combination of characters from various morphological complexes, which are described in detail using different methodologies, including radiography, whole-specimen clearing and double-staining procedures, and tridimensional computer nanotomography (3D nano-CT).


Asunto(s)
Bagres , Bosque Lluvioso , Animales , Filogenia , Brasil , Ecosistema
6.
Nature ; 472(7343): 295, 2011 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-21512561
7.
Zootaxa ; 4560(3): zootaxa.4560.3.7, 2019 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-31716571

RESUMEN

Different authors have suggested that Anabates pulvericolor Sclater, 1858 might be the valid nomen for Synallaxis propinqua Pelzeln, 1859 or for Synallaxis gujanensis huallagae Cory, 1919. However, due to doubts regarding the taxonomic identity of Anabates pulvericolor Sclater, 1858, of which the unique type is lost, neither of these nomina has been displaced by the senior nomen pulvericolor. Our analysis of the case reveals that Anabates pulvericolor Sclater, 1858 is correctly identifiable with Synallaxis gujanensis huallagae Cory, 1919, of which it is a senior subjective synonym. According to the Code, the senior subjective synonym Synallaxis gujanensis pulvericolor (Sclater, 1858) should be adopted. Given the fact that the holotype of Anabates pulvericolor Sclater, 1858 is missing and that it has been impossible to identify it from its description until now, we designate a neotype from"Río Napo, Ecuador", its original type locality.


Asunto(s)
Passeriformes , Animales , Ecuador
9.
Biota Neotrop. (Online, Ed. ingl.) ; 22(spe): e20221426, 2022. graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1420331

RESUMEN

Abstract Scientific collections constitute a valuable source for contributions to scientific research and the training of human resources in systematics, but also other areas of biological knowledge. In this contribution, we intend to discuss these advancements in collections and the role played by FAPESP in sponsoring them, as well as a general overview of the zoological collections in São Paulo state. We also aim to stress the importance of zoological collections and the need for continuous logistic and financial support from institutions and research agencies to maintain and develop these unique repositories of biodiversity. From 1980 to the present, FAPESP supported 118 research projects focused on several areas of zoology that are directly or indirectly associated with collections. There is a constant growth in the number of projects, and the financial support provided by FAPESP through the Biota Program was paramount for the advancement of our knowledge of biodiversity in Brazil. Parallel to the scientific advances, but not less important, this support allowed curators to increase the number of specimens, and to organize, maintain and digitize them in these valuable and irreplaceable collections. Regarding the lack of new taxonomists, it is essential that FAPESP and universities in São Paulo encourage the formation of new academics in zoological groups where specialists are rare. Considering the investment provided by FAPESP, it is quite important that the institutions that benefited from these resources took greater responsibility to safeguard these collections, and they should consider including resources on their budgets to obtain safety certificates, ensuring their permanence for many generations to come. Zoological collections are a heritage of humanity and are essential not only for the improvement of our knowledge of biodiversity but also with direct applications, among other services provided by these biological resources. It is important that research and teaching institutions in São Paulo that house specimens under their care start to value more this important patrimony and this heritage, as these collections represent the most valuable testimony of our impressive biodiversity, records of our past, and windows to our future, essential to our academic, scientific, cultural and social sovereignty.


Resumo As coleções científicas constituem uma fonte valiosa para contribuições à pesquisa científica e para a formação de recursos humanos em sistemática, mas também em outras áreas do conhecimento biológico. Nesta contribuição, pretendemos discutir esses avanços nas coleções e o papel desempenhado pela FAPESP no seu patrocínio, bem como um panorama geral das coleções zoológicas do estado de São Paulo. Também pretendemos enfatizar a importância das coleções zoológicas e a necessidade de apoio logístico e financeiro contínuo de instituições e agências de pesquisa para manter e desenvolver esses repositórios únicos de biodiversidade. Ao longo de 1980 até os dias atuais, a FAPESP apoiou 118 projetos de pesquisa focados em diversas áreas da zoologia, direta ou indiretamente associados a coleções. Há um crescimento constante no número de projetos, e o apoio financeiro da FAPESP por meio do Programa Biota foi fundamental para o avanço do nosso conhecimento sobre a biodiversidade no Brasil. Paralelamente aos avanços científicos, mas não menos importante, este apoio permitiu aos curadores aumentar o número de exemplares, e organizá-los, mantê-los e digitalizá-los nestas valiosas e insubstituíveis coleções. Em relação à falta de novos taxonomistas, é fundamental que a FAPESP e as universidades paulistas estimulem a formação de novos acadêmicos em grupos zoológicos onde os especialistas são raros. Considerando o investimento realizado pela FAPESP, é de suma importância que as instituições beneficiadas com esses recursos tenham maior responsabilidade na salvaguarda desses acervos, devendo considerar a inclusão de recursos em seus orçamentos para obtenção de certificados de segurança, garantindo sua permanência por muitas gerações. As coleções zoológicas são patrimônio da humanidade, e são essenciais não apenas para o aprimoramento do nosso conhecimento sobre a biodiversidade, mas também com aplicações diretas, entre outros serviços prestados por esses recursos biológicos. É importante que as instituições de pesquisa e ensino paulistas que abrigam exemplares sob seus cuidados passem a valorizar mais esse importante patrimônio e essa herança, pois essas coleções representam o testemunho mais valioso de nossa impressionante biodiversidade, registros do nosso passado e janelas para o nosso futuro, essenciais à nossa soberania acadêmica, científica, cultural e social.

10.
Neotrop. ichthyol ; 16(3): [e180059], out. 2018. ilus, graf, tab
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-963954

RESUMEN

Fossil gonorynchiform fishes range from the Lower Cretaceous to the early Miocene, and are represented by a few dozen living species. The order is currently divided into two major clades: Gonorynchoidei, which includes the families Gonorynchidae and Kneriidae, and Chanoidei, encompassing a single family, Chanidae, with a single recent species, the Indo-Pacific Chanos chanos, and several fossil taxa. Chanidae includes some poorly known taxa, such as Dastilbe moraesi, described from the Aptian (Lower Cretaceous) of the Areado Formation, Sanfranciscana basin, Brazil. This species is currently considered to be a junior synonym of the type species of its genus, Dastilbe crandalli, from Santana Formation, Aptian, northeastern Brazil. The analysis of abundant D. moraesi specimens revealed several new morphological features, many of which had previously been misinterpreted. Dastilbe moraesi was incorporated into a gonorynchiform character matrix as revised and modified for the Chanidae. We obtained a single most parsimonious tree in which D. moraesi is distinct and phylogenetically apart from D. crandalli. According our analysis, D. moraesi forms a sister pair with Chanos, a clade which is closely related to Tharrhias, all composing the tribe Chanini.(AU)


Gonorynchiformes fósseis ocorrem desde do Cretáceo inferior ao Mioceno inferior, e são representados por alguns representantes viventes. A ordem está dividida atualmente em dois clados principais: Gonorynchoidei, que inclui as famílias Gonorynchidae e Kneriidae, e Chanoidei, compreendendo uma única família, Chanidae, com uma única espécie vivente, Chanos chanos, do Indo-Pacífico, além de vários representantes fósseis. Chanidae inclui alguns táxons problemáticos, tais como Dastilbe moraesi, descrito do Aptiano (Cretáceo Inferior) da Formação Areado, bacia Sanfranciscana, Brasil. Esta espécie é atualmente considerada um sinônimo júnior da espécie-tipo de seu gênero, Dastilbe crandalli, da Formação Santana, Aptiano do nordeste do Brasil. A análise de abundante material de D. moraesi revelou várias novas características anatômicas, muitas das quais haviam sido previamente mal interpretadas. Dastilbe moraesi foi incorporado em uma matriz revisada de caracteres da família Chanidae. Nós obtivemos uma única árvore mais parcimoniosa na qual D. moraesi é distinto e filogeneticamente distante de D. crandalli. De acordo com nossa análise, D. moraesi é o grupo-irmão de Chanos, um clado intimamente relacionado a Tharrhias, com todos compondo a tribo Chanini.(AU)


Asunto(s)
Animales , Filogenia , Peces/genética , Fósiles
11.
Neotrop. ichthyol ; 8(4): 673-706, 2010. ilus, tab
Artículo en Inglés | LILACS | ID: lil-571567

RESUMEN

Rhamdiopsis krugi, a new troglobitic heptapterid catfish, is described from the caves of Chapada Diamantina, State of Bahia, northeastern Brazil. This species, although frequently cited in the scientific literature along the last seventeen years, remained undescribed largely due to its uncertain phylogenetic affinities. The generic assignment of R. krugi was clouded largely by its high number of unusual morphological features (some related to cave life), for instance: absence of eyes and body pigmentation; presence of a widely exposed pseudotympanum; posterior border of the anterior branch and anterior margin of the arborescent portion of the posterior branch of the transverse process of fourth vertebra joined; dorsal hypural plate commonly with seven rays; ventral caudal plate usually with six rays; dorsal and ventral caudal-fin lobes typically with six branched fin rays each; 38-39 vertebrae; anal fin with 14-17 rays; and lateral line very short. Rhamdiopsis krugi can be easily distinguished from its congeners, R. microcephala and R. moreirai, by its troglomorphic features and by the presence of a shorter lateral line, fewer vertebrae and anal-fin rays, pattern of branching of caudal-fin rays, and several attributes of skeletal system. The affinities of this new species are discussed in light of current phylogenetic knowledge of the family Heptapteridae. Incongruent derived characters do not allow selection of a particular hypothesis of sister group relationships among species of Rhamdiopsis. The occurrence of R. krugi in the rio Paraguaçu basin is possibly due to an event of hydrological capture from a section of the middle portion of the rio São Francisco basin, caused by tectonic events. The semi-arid region where R. krugi presently lives was probably covered by a wide forested area during a humid cycle in Quaternary. A summary of natural history and ecology data of R. krugi, as well as notes on its conservation, are provided. We also offer comments on the morphological plasticity of R. krugi.


Rhamdiopsis krugi, um novo bagre heptapterídeo troglóbio, é descrito de cavernas da Chapada Diamantina, Estado da Bahia, nordeste do Brasil. Esta espécie, embora frequentemente citada na literatura ao longo dos últimos dezessete anos, não foi descrita antes em função das suas afinidades filogenéticas incertas. A posição genérica de R. krugi foi obscurecida principalmente pelo seu alto número de caracteres morfológicos incomuns (parte deles relacionada à vida nas cavernas), como por exemplo: ausência de olhos e de pigmentação corporal; presença de um pseudotímpano amplamente exposto; borda posterior do ramo anterior e margem anterior da porção arborescente do ramo posterior do processo transverso da quarta vértebra conectados um ao outro; placa hipural dorsal normalmente com sete raios; placa caudal ventral usualmente com seis raios; lobos dorsal e ventral da nadadeira caudal tipicamente com seis raios ramificados cada; 38-39 vértebras; nadadeira anal com 14-17 raios; e linha lateral muito curta. Rhamdiopsis krugi pode ser facilmente distinguida de seus congêneres, R. microcephala e R. moreirai, por seus caracteres troglomórficos e pela presença de uma linha lateral mais curta, menos vértebras e raios na nadadeira anal, padrão de ramificação dos raios da nadadeira caudal e vários atributos do sistema esquelético. As afinidades desta nova espécie são discutidas à luz do conhecimento atual sobre a filogenia da família Heptapteridae. Caracteres derivados incongruentes não permitem optar por uma hipótese particular de relação de grupo-irmão entre as espécies de Rhamdiopsis. A ocorrência de R. krugi na bacia do rio Paraguaçu é devida, possivelmente, a um evento de captura hidrológica de uma seção da porção média da bacia do rio São Francisco, ocasionada por eventos tectônicos. A região semi-árida onde R. krugi atualmente vive estava provavelmente coberta por uma ampla floresta durante um ciclo úmido no Quaternário. Um sumário das informações sobre a história natural e ecologia de R. krugi, assim como observações sobre sua conservação, são apresentadas. Apresentamos também comentários sobre a plasticidade morfológica de R. krugi.


Asunto(s)
Animales , Peces/anatomía & histología , Peces/genética
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