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A new species of freshwater crab genus Fredius Pretzmann, 1967 (Crustacea: Brachyura: Pseudothelphusidae) from a naturally isolated orographic forest enclave within the semiarid Caatinga in Ceará, northeastern Brazil
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 r...
Autores principales: | , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
PeerJ Inc.
2020
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7331627/ https://www.ncbi.nlm.nih.gov/pubmed/32655990 http://dx.doi.org/10.7717/peerj.9370 |
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author | Santos, Livanio C. Tavares, Marcos Silva, José R.F. Cervini, Marcelo Pinheiro, Allysson P. Santana, William |
author_facet | Santos, Livanio C. Tavares, Marcos Silva, José R.F. Cervini, Marcelo Pinheiro, Allysson P. Santana, William |
author_sort | Santos, Livanio C. |
collection | PubMed |
description | 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 |
format | Online Article Text |
id | pubmed-7331627 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2020 |
publisher | PeerJ Inc. |
record_format | MEDLINE/PubMed |
spelling | pubmed-73316272020-07-09 A new species of freshwater crab genus Fredius Pretzmann, 1967 (Crustacea: Brachyura: Pseudothelphusidae) from a naturally isolated orographic forest enclave within the semiarid Caatinga in Ceará, northeastern Brazil Santos, Livanio C. Tavares, Marcos Silva, José R.F. Cervini, Marcelo Pinheiro, Allysson P. Santana, William PeerJ Biodiversity 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 PeerJ Inc. 2020-06-29 /pmc/articles/PMC7331627/ /pubmed/32655990 http://dx.doi.org/10.7717/peerj.9370 Text en ©2020 Santos et al. https://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ) and either DOI or URL of the article must be cited. |
spellingShingle | Biodiversity Santos, Livanio C. Tavares, Marcos Silva, José R.F. Cervini, Marcelo Pinheiro, Allysson P. Santana, William A new species of freshwater crab genus Fredius Pretzmann, 1967 (Crustacea: Brachyura: Pseudothelphusidae) from a naturally isolated orographic forest enclave within the semiarid Caatinga in Ceará, northeastern Brazil |
title | A new species of freshwater crab genus Fredius Pretzmann, 1967 (Crustacea: Brachyura: Pseudothelphusidae) from a naturally isolated orographic forest enclave within the semiarid Caatinga in Ceará, northeastern Brazil |
title_full | A new species of freshwater crab genus Fredius Pretzmann, 1967 (Crustacea: Brachyura: Pseudothelphusidae) from a naturally isolated orographic forest enclave within the semiarid Caatinga in Ceará, northeastern Brazil |
title_fullStr | A new species of freshwater crab genus Fredius Pretzmann, 1967 (Crustacea: Brachyura: Pseudothelphusidae) from a naturally isolated orographic forest enclave within the semiarid Caatinga in Ceará, northeastern Brazil |
title_full_unstemmed | A new species of freshwater crab genus Fredius Pretzmann, 1967 (Crustacea: Brachyura: Pseudothelphusidae) from a naturally isolated orographic forest enclave within the semiarid Caatinga in Ceará, northeastern Brazil |
title_short | A new species of freshwater crab genus Fredius Pretzmann, 1967 (Crustacea: Brachyura: Pseudothelphusidae) from a naturally isolated orographic forest enclave within the semiarid Caatinga in Ceará, northeastern Brazil |
title_sort | new species of freshwater crab genus fredius pretzmann, 1967 (crustacea: brachyura: pseudothelphusidae) from a naturally isolated orographic forest enclave within the semiarid caatinga in ceará, northeastern brazil |
topic | Biodiversity |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7331627/ https://www.ncbi.nlm.nih.gov/pubmed/32655990 http://dx.doi.org/10.7717/peerj.9370 |
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