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1.
Sci Rep ; 13(1): 14549, 2023 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-37666850

RESUMEN

Direct evidence of paleo-parasitism in crustaceans is very scarce. Epicaridean isopods are obligatory parasites of crustaceans, including decapods such as crabs, shrimps, and lobsters. Their interaction with hosts is known from fossils as far back as the Jurassic through deformations of the branchial cuticle on the hosts. Their small size and low fossilization potential, outside of those larvae that have been found in amber, makes understanding the group's evolution challenging. Here, we report the oldest evidence of paleo-parasitism in marine shrimps and an imprint of a putative adult parasite that appears to be an epicaridean isopod. Our results suggest that the parasite-host interaction between epicaridean isopods and marine shrimps started at least 110 million years ago, and the Tethys Sea was a possible dispersal pathway for this lineage of parasites during the Jurassic and Cretaceous, as known for other marine organisms through most of the Mesozoic and Cenozoic. The oldest fossil records of bopyrid swellings associated with a large number of decapods from the Jurassic in Europe suggest that the Tethys region was a center of epicaridean distribution as a whole. Recent parasitic isopods found on dendrobranchiate shrimps are restricted to the Indo-Pacific and may represent a relict group of a lineage of parasites more widely distributed in the Mesozoic.


Asunto(s)
Decápodos , Gastrópodos , Isópodos , Animales , Fósiles , Ámbar , Europa (Continente)
3.
Zootaxa ; 4903(2): zootaxa.4903.2.8, 2021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-33757101

RESUMEN

A new species of pseudothelphusid crab of the tribe Kingsleyini Ortmann, 1897, from the southern Amazon region in the state of Rondônia, Brazil, is described and illustrated. Fredius avilai n. sp. can be readily distinguished from its congeners by the following characters of the male first gonopod: mesial lobe elongated, convoluted, proximal portion directed laterally, distal portion sharply recurved in abdominal direction; marginal process rounded, not projected over distal opening of spermatic channel, merging with distal portion of abdominal surface after a shallow depression; lateral suture well demarcated along mesoabdominal surface of stem, distal portion directed inwards. The assignment of the new species to the genus Fredius Pretzmann, 1967 and its affinities with another closed related species are discussed.


Asunto(s)
Ascarídidos , Braquiuros , Animales , Brasil , Masculino
4.
PeerJ ; 8: e9370, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32655990

RESUMEN

A new species of freshwater crab, Fredius ibiapaba, is described and illustrated from a mid-altitude forested patch in Ipú (Ibiapaba plateau, Ceará, northeastern Brazil), between 635 to 782 m. The new species can be separated from its congeners by the morphology of its first gonopod: proximal half remarkably swollen, sloping abruptly downwards distally to a nearly right-angular shoulder; mesial lobe much smaller than cephalic spine; cephalic lobe moderately developed; auxiliary lobe lip, delimiting field of apical spines, protruded all the way to distal margin of auxiliary lobe. Comparative 16S rDNA sequencing used to infer the phylogenetic placement of Fredius ibiapaba n. sp. revealed that it is the sister taxon of F. reflexifrons, a species which occurs allopatrically in the Amazon and Atlantic basin's lowlands (<100 m). Fredius ibiapaba n. sp. and F. reflexifrons are highly dependent upon humidity and most probably were once part of an ancestral population living in a wide humid territory. Shrinking humid forests during several dry periods of the Tertiary and Quaternary likely have resulted in the fragmentation of the ancestral humid area and hence of the ancestral crab population. Fredius reflexifrons evolved and spread in a lowland, humid river basin (Amazon and Atlantic basins), whilst F. ibiapaba n. sp. evolved isolated on the top of a humid plateau. The two species are now separated by a vast intervening area occupied by the semiarid Caatinga.

5.
An Acad Bras Cienc ; 92(1): e20180814, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32236297

RESUMEN

Freshwater crabs are important components of aquatic ecosystems; however, their distributions are restricted because of characteristics of their life history, which hinder conservation strategies. Fredius reflexifrons is a widely distributed freshwater crab of the Amazon basin with relictual occurrences in small wetlands on the Planalto da Ibiapaba in Northeastern Brazil. Habitat degradation, destruction of forest patches, channeling of water bodies, and the use of land for legume cropping can seriously impact the species by leading to the extinction of its relic populations, which have limited distributions in the Área de Proteção Ambiental (APA; Environmental Protection Area) Bica do Ipu of the Planalto da Ibiapaba. The objectives of this study were to assess the distribution of F. reflexifrons in APA Bica do Ipu, identify the main impacts from anthropic activities, suggest potential actions to mitigate these impacts, besides providing recommendations for the expansion of the APA. Fredius reflexifrons was recorded in eleven sites in the Planalto da Ibiapaba, of which nine are new records and five are not located within the APA. These findings evidence the need of expanding the APA to encompass the newly known distribution of F. reflexifrons in order to assure its protection.


Asunto(s)
Distribución Animal , Braquiuros/clasificación , Conservación de los Recursos Naturales , Agua Dulce , Animales , Brasil , Humedales
6.
An Acad Bras Cienc ; 89(2): 1047-1049, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28640351

RESUMEN

Occurrence of Dendrocephalus brasiliensis Pesta, 1921 (Crustacea, Anostraca) in the Caras river, southern Ceara, Brazil. The specimens were collected in March and April 2014. The new occurrence extends the distribution and update area of occupancy of the species, which is characterized by a specific habitat: temporary lakes.


Asunto(s)
Anostraca , Ríos , Distribución Animal , Animales , Brasil , Ecosistema , Femenino , Masculino
7.
An. acad. bras. ciênc ; 89(2): 1047-1049, Apr.-June 2017. graf
Artículo en Inglés | LILACS | ID: biblio-886695

RESUMEN

ABSTRACT Occurrence of Dendrocephalus brasiliensis Pesta, 1921 (Crustacea, Anostraca) in the Caras river, southern Ceara, Brazil. The specimens were collected in March and April 2014. The new occurrence extends the distribution and update area of occupancy of the species, which is characterized by a specific habitat: temporary lakes.


Asunto(s)
Animales , Masculino , Femenino , Anostraca , Ríos , Brasil , Ecosistema , Distribución Animal
8.
J Taibah Univ Med Sci ; 12(6): 483-491, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31435283

RESUMEN

OBJECTIVES: Postgraduate programmes around the world are periodically subjected to research performance evaluation through bibliometric indicators. In this research, we characterized and compared the research performance of 15 universities from Northeastern Brazil, in which 13 were among the top Universities of the Latin America. METHODS: Specifically, total documents, citations and the h-index of each university were retrieved from the Elsevier Scopus database and were analysed not only for historical scientific achievement but also across the period of the past 6 years (2010-2015). Using these bibliometric indicators, we also investigated the performance of programmes at these Universities that have their papers indexed in the Scopus database under the category of "Pharmacology, Toxicology and Pharmaceuticals" for the same period. RESULTS: We found that the Federal University of Pernambuco (UFPE) and the Federal University of Ceará (UFC) were the most productive institutions, producing 17847 and 15048 documents, respectively. The number of papers published by each of these universities in the past six years represented more than 50% of their entire productivity. With regards to their scientific output in "Pharmacology, Toxicology and Pharmaceutics", UFC showed the highest number of published documents followed by UFPE and the Federal University of Paraíba (UFPB). UFC received the highest h-index (with and without self-citations) and number of citations and shared their most cited papers with foreign institutions from the USA and Germany. However, papers from UFC were published in journals with lower impact factors (2.322). CONCLUSIONS: The present study shows where each of these universities stands and can be helpful in identifying potential collaborators in these areas of knowledge.

9.
Zootaxa ; 4171(2): 365-372, 2016 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-27701230

RESUMEN

A new species of freshwater crab, Kingsleya attenboroughi n. sp., from the Arajara district, Ceará state, Brazil, is described and illustrated. The new species differs from congeners by having a short apical plate in the first gonopod, with anteriorly directed lobes and proximally angular; proximal lobe of the apical plate with conspicuous semicircular protuberance in mesial and sternal views; marginal process protruded, projecting mesially in sternal view and subquadrate in mesial view; and field of apical spines narrow, tapering distally, with small spines concentrated proximally. Opportunity is taken to illustrate K. gustavoi Magalhães, 2005, the closest allied species of K. attenboroughi n. sp. A key for the species of Kingsleya Ortmann, 1897 is provided.


Asunto(s)
Braquiuros/anatomía & histología , Braquiuros/clasificación , Animales , Brasil , Especies en Peligro de Extinción , Femenino , Masculino
10.
Anal Chem ; 87(19): 10088-95, 2015 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-26344658

RESUMEN

We used here a scanning electron microscopy approach that detected backscattered electrons (BSEs) and X-rays (from ionization processes) along a large-field (LF) scan, applied on a Cretaceous fossil of a shrimp (area ∼280 mm(2)) from the Araripe Sedimentary Basin. High-definition LF images from BSEs and X-rays were essentially generated by assembling thousands of magnified images that covered the whole area of the fossil, thus unveiling morphological and compositional aspects at length scales from micrometers to centimeters. Morphological features of the shrimp such as pleopods, pereopods, and antennae located at near-surface layers (undetected by photography techniques) were unveiled in detail by LF BSE images and in calcium and phosphorus elemental maps (mineralized as hydroxyapatite). LF elemental maps for zinc and sulfur indicated a rare fossilization event observed for the first time in fossils from the Araripe Sedimentary Basin: the mineralization of zinc sulfide interfacing to hydroxyapatite in the fossil. Finally, a dimensional analysis of the phosphorus map led to an important finding: the existence of a fractal characteristic (D = 1.63) for the hydroxyapatite-matrix interface, a result of physical-geological events occurring with spatial scale invariance on the specimen, over millions of years.


Asunto(s)
Decápodos/anatomía & histología , Fósiles/anatomía & histología , Microscopía Electrónica de Rastreo/métodos , Animales , Decápodos/química , Durapatita/análisis , Fósforo/análisis , Espectrometría por Rayos X/métodos , Rayos X
11.
An Acad Bras Cienc ; 86(2): 663-670, 2014 06.
Artículo en Inglés | MEDLINE | ID: mdl-24789213

RESUMEN

The fossil shrimp Araripenaeus timidus n. gen. n. sp. is the first fossil Penaeoidea from Brazil. Here, we describe, illustrate and compare it with Paleomattea deliciosa, a fossil Sergestoidea (Dendrobranchiata) previously described from the same region. The material of the early Cretaceous (Albian) was collected in the town of Jardim, south of the state of Ceará, in the superior septarian concretion level of the Romualdo Formation. Additionally, a second specimen of Kellnerius jamacaruensis was found in the same site of the Araripe Basin.

12.
Zootaxa ; 3620: 293-300, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-26120711

RESUMEN

A new fossil caridean shrimp, Kellnerius jamacaruensis n. gen. n. sp., of the early Cretaceous (Albian) from the Romualdo Formation, Araripe Basin, northeastern Brazil is described and illustrated. The new species is compared to known fossil palaemonids found in Brazil. Kellnerius jamacaruensis n. gen. n. sp. is easily differentiated from the other palaemonids by a rostrum with 5 spines, an enlarged scaphocerite that is longer than the rostrum, and a third somite with a distinct groove in the tergite that does not extend to the pleurite.


Asunto(s)
Decápodos/anatomía & histología , Decápodos/clasificación , Fósiles/anatomía & histología , Animales , Brasil
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