1,721,007 research outputs found
FIGURE 1 in A new species of hermit crab of the genus Pagurus Fabricius, 1775 (Crustacea: Anomura: Paguridae) from north-western Africa
No full textFIGURE 1. Maximum likelihood phylogenetic tree based on mitochondrial cytochrome c oxidase subunit I (COI) barcode sequences of Pagurus representatives, using 1000 nonparametric bootstrap replicates. Numbers on the branches represent ML bootstrap values; only bootstrap values>70 (ML) are included. Anapagurus laevis is included as outgroup. GenBank accession codes and major distribution areas are indicated for each species; sequences generated in this study are shown in bold.Published as part of Almón, Bruno, Cuesta, Jose A. & García-Raso, J. Enrique, 2022, A new species of hermit crab of the genus Pagurus Fabricius, 1775 (Crustacea: Anomura: Paguridae) from north-western Africa, pp. 426-440 in Zootaxa 5209 (4) on page 429, DOI: 10.11646/zootaxa.5209.4.2, http://zenodo.org/record/733382
Figure 8. A in Redescription of the hermit crab Diogenes pugilator (Decapoda: Anomura) reveals the existence of a species complex in the Atlanto-Mediterranean transition zone, resulting in the resurrection of D. curvimanus and the description of a new species
No full textFigure 8. A, maximum likelihood phylogenetic tree based on the concatenated mitochondrial data (COI + 16S) using 1000 nonparametric bootstrap replicates. Numbers on the branches represent ML bootstrap values; only bootstrap values> 70 (ML) are included. The species Dardanus arrosor and Paguristes eremita are included as outgroups. Groups recovered from the ABGD analysis (G.1–G.9) are also included. B, histogram of genetic distances (JC69 Jukes–Cantor) showing the barcoding gap for the COI gene.Published as part of Almón, Bruno, Cuesta, Jose A., Schubart, Christoph D., Armenia, Lisa & García-Raso, J. Enrique, 2022, Redescription of the hermit crab Diogenes pugilator (Decapoda: Anomura) reveals the existence of a species complex in the Atlanto-Mediterranean transition zone, resulting in the resurrection of D. curvimanus and the description of a new species, pp. 1116-1146 in Zoological Journal of the Linnean Society 195 on page 1141, DOI: 10.1093/zoolinnean/zlab093, http://zenodo.org/record/699381
Descripción de patrones únicos de coloración en vivo como herramienta para la discriminación de especies de cangrejos ermitaños en la península ibérica
Full text linkThe unique colour patterns of the hermit crab species inhabiting the Iberian Peninsula and geographically close areas are studied based on colour patterns observed in live specimens either in the field or live in the laboratory. Live colour patterns are shown to be useful for differentiating species in the Paguroidea from Iberian waters. Colour information has not been frequently documented in previous studies, mainly because of difficulties in accessing live specimens. Up to 51 species are currently recorded within the study area, 45 of which are included in the present work, focusing on the distinctive colour traits for each species that can be observed in the field. A complete key for identifying the species within the study area based on colour patterns is included. This study is the first attempt to put in place this type of tool oriented to field work. Further studies will be required to complete and update this information, especially for species which are scarce or difficult to observe alive.El estudio de los patrones de coloración en ejemplares vivos observados tanto en el campo como en laboratorio, han permitido investigar la existencia de patrones de coloración distintivos para las especies de cangrejos ermitaños que habitan en la península ibérica y zonas geográficamente cercanas. Estos patrones de coloración han demostrado ser de gran utilidad en los Paguroidea de aguas Ibéricas para la identificación de especies. La información relativa al color ha sido frecuentemente obviada en el pasado, principalmente debido a las dificultades para acceder a los ejemplares vivos. En la actualidad existen alrededor de 51 especies registradas en la zona de estudio, 45 de las cuales se incluyen en el presente trabajo, poniendo el foco en los rasgos de color distintivos de cada especie que pueden observarse en el campo. Se incluye una clave completa para la identificación de las especies dentro del área de estudio basada en los patrones de color. Este estudio es el primer intento de implementar este tipo de herramienta orientada al trabajo de campo. Serán necesarios más estudios para completar y actualizar esta información, especialmente para aquellas especies que son escasas o difíciles de observar en vivo
A New Varunid Subfamily (Decapoda, Brachyura, Grapsoidea, Varunidae) for Crabs From European and West African Waters, With the Description of Two New Genera and Two New Species
No full text[Data Availability Statement]
The data underlying this article are available in the article. DNA sequences and related data are publicly available on GenBank (https://www.ncbi.nlm.nih.gov/genbank/). The data associated with each of the specimens examined are included in the text, in the appropriate sections. The accession number for sequences downloaded from public databases is included in Table 2 along with those generated for this project.The subfamily Asthenognathinae is currently composed of a single genus, Asthenognathus Stimpson, 1858, with three species, A. inaequipes Stimpson, 1858, A. hexagonus Rathbun, 1909 (both from the Indo-West Pacific), and A. atlanticus Monod, 1933 (European and West Tropical African waters). All Asthenognathus species are difficult to collect due to their small size and symbiotic lifestyle with fossorial organisms. The examination of specimens of A. atlanticus from European and West African waters deposited in scientific collections shows significant morphological and molecular differences with the Indo-West Pacific species, which makes the creation of a new subfamily (Schubartinae n. subf.) and two new genera necessary. The identity of A. atlanticus, the only species found along the East Atlantic and Mediterranean waters, is clarified, and a new genus, Dudekemus n. gen., is established for this species, Dudekemus atlanticus (Monod, 1933) n. gen., n. comb. This study also describes another new genus, Schubartus n. gen., based on morphological differences and genetic data. These two new genera can be distinguished from Asthenognathus by the carapace proportions and differences in the structures of the male pleonal somites, pereiopods and endostome. In addition, two new species distributed in Guinea-Bissau and Mauritania, Schubartus mauritanicus n. gen., sp. nov., and S. ngankeeae n. gen., n. sp., are described. A key for species of the subfamilies Asthenognathinae and Schubartinae n.subf. is provided.Funding for this work was provided by Junta de Andalucía, Spain, to RNM 141 Research Group. Funding for open access fees has been provided by the University of Málaga/CBUA.
urn:lsid:zoobank.org:pub:8BC1704B-6097-4636-96F8-70891DDA77ECPeer reviewe
A Multilevel Biodiversity Approach of the Hermit Crabs in the Iberian Peninsula and Ultraperipheral Territories
No full textThe crustaceans of the superfamily Paguroidea constitute one of the most diverse groups within the Decapoda, exhibiting remarkable morphological and ecological diversity. Despite the relatively high number of described species worldwide, there are still many gaps in the knowledge of this group, particularly regarding genetic information. This study aims to update the geographic distribution information currently available for the hermit crab species in the Iberian Peninsula, Azores, Canary Islands, and Madeira, and generate a molecular database supported by morphological identification. The results are summarized in an updated list of Paguroidea recorded in the study area, which comprises a total of 55 species, representing a significant increase from previous compilations. Newly generated sequences, including those from the study area and closely related species from other areas, provide the first molecular information for 35 out of the 70 species analyzed. Phylogenetic analyses provide evidence of the species delimitation capabilities of molecular tools when reliable morphology-based information is available. Molecular analyses using two mitochondrial markers largely corresponded, supporting most traditionally established species and validating the morphological characters used for delimitation. Specifically, the COI gene showed better results and clearer topologies, suggesting greater utility for exploring species delimitation when using single-gene identification as a DNA barcode. Overall, the results of this long-term study will improve the capabilities for species delimitation, in addition to updating the composition and richness of species in the area.Peer reviewe
Marine crabs from African waters housed in the Museo Nacional de Ciencias Naturales (MNCN-CSIC): An opportunity for biogeographic and systematic studies. Part I: Heterotremata (Decapoda, Brachyura)
No full textZoological collections are the main repositories of biodiversity for specific regions or taxa. However, they often lack promotion and consequently remain largely unknown to the general public or even for specialists. Moreover, many of these collections are at risk of deterioration and, in many cases, lack taxonomic review. Founded in 1771, the Museo Nacional de Ciencias Naturales (MNCN; Madrid, Spain) is one of the oldest Natural History Museums in the world and one of the most important scientific research institutions in the field of Natural Sciences in Europe. The review conducted in this study resulted in an annotated catalogue of marine Heterotremata crabs, documenting 83 species across 21 families from the MNCN collection. It was found that only 21.9% of the specimens had been correctly identified, while 78.1% were either unidentified, identified only to the family level, or misidentified. This highlights a significant loss of biodiversity information and missed opportunities for identifying new species, as many specimens had been inadequately identified for up to 175 years. The review also expanded the known geographic distribution of several species, with the first-time recordings in regions such as Mauritian, Equatorial Guinean, Moroccan, Ghanaian, and São Tomé and Príncipe waters. The study emphasizes the importance of access to zoological collections and collaboration with specialists to enhance our understanding of biodiversity.Peer reviewe
Marine Crabs from African Waters Housed in the Museo Nacional de Ciencias Naturales (MNCN-CSIC)—An Opportunity for Biogeographic and Systematic Studies—Part II: Thoracotremata
No full textInformation on the specimens examined can be obtained by contacting the curator at https://www.mncn.csic.es/en/colecciones/cientificas/arthropods (accessed on 20 August 2025).Zoological collections are essential for preserving regional biodiversity but often lack taxonomic updates, risking data loss. This work supposes the continuation of a review of the African marine crabs housed at the Crustacean collection of the Museo Nacional de Ciencias Naturales (MNCN) in Madrid. Part I, Heterotremata, revealed that only 21.9% of the specimens were correctly identified. In this new study focused on Thoracotremata species, 197 specimens (59 records) were reviewed, and this new study reveals similar results to Part I: 22.9% of the reviewed specimens were previously correctly identified (less than 29% when considering records), meaning that around 77.2% of the African Thoracotremata specimens housed in the MNCN were either misidentified or not identified at all. This highlights the importance of the taxonomic reviews made by specialists of specimens housed in both historical and non-historical scientific collections. This time we have used DNA barcodes (16S and COI) to confirm identifications or to add new molecular data to species without previous DNA sequences known. DNA sequences (16S and/or COI) were obtained for seven species. It has been a challenge to obtain sequences from specimens preserved 60 to 200 years ago.This research received no external funding.Peer reviewe
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Marine Crabs of Guinea-Bissau, with Emphasis on the Deep Fauna, Supported by an Integrative Taxonomy
No full text© 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).The updated checklist of the marine crabs of Guinea-Bissau presented in this work is the result of consolidating decades of research, ongoing systematic revisions of the regional carcinofauna, and the inclusion of new records. DNA markers and morphological analyses for accurate identifications are integrated. Sixty-one species are mentioned in this list after reviewing specimens from scientific collections and literature. Of these 61 species listed, the presence of 51 species in Guinea-Bissau is confirmed, and 21 are reported for the first time in the area. A total of 98 sequences were obtained from 41 species (51 of 16S for 38 species and 47 of COI for 35 species), and 48 sequences (24 of 16S and 24 of COI) were the first ones obtained for 29 species. The maximum or minimum bathymetric range is expanded by 16 species, and for other six species, a color description is provided for the first time. Merocryptus obsoletus is synonymized as Merocryptus boletifer. The present study will be a useful baseline for gathering further ecological information about globally important marine taxa, not only in Guinea-Bissau but about African brachyurans in general.With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)Peer reviewe
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