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Borsa, P., Durand, J. D., Shen, K. N., Arlyza, I. S., Solihin, D. D., & Berrebi, P. (2013). Himantura tutul sp nov (Myliobatoidei: Dasyatidae), a new ocellated whipray from the tropical Indo-West Pacific, described from its cytochrome-oxidase I gene sequence. Comptes Rendus Biologies, 336(2), 82–92.
Résumé: It has been previously established that the Leopard Whipray, Himantura leoparda, consists of two genetically isolated, cryptic species, provisionally designated as 'Cluster 1' and 'Cluster 4' (Arlyza et al., Mol. Phylogenet. Evol. 65 (2013) [11). Here, we show that the two cryptic species differ by the spotting patterns on the dorsal surface of adults: Cluster-4 individuals tend to have larger-ocellated spots, which also more often have a continuous contour than Cluster-1 individuals. We show that H. leopard a's holotype has the typical larger-ocellated spot pattern, designating Cluster 4 as the actual H. leoparda. The other species (Cluster 1) is described as Himantura tutul sp. nov. on the basis of the nucleotide sequence of a 655-base pair fragment of its cytochrome-oxidase I gene (GENBANK accession No. JX263335). Nucleotide synapomorphies at this locus clearly distinguish H. tutul sp. nov. from all three other valid species in the H. uarnak species complex, namely H. leoparda, H. uarnak, and H. undulata. H. tutul sp. nov. has a wide distribution in the Indo-West Pacific, from the shores of eastern Africa to the Indo-Malay archipelago. H. leoparda under its new definition has a similarly wide Indo-West Pacific distribution. (C) 2013 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.
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Durand, J. - D., & Borsa, P. (2015). Mitochondrial phylogeny of grey mullets (Acanthopterygii: Mugilidae) suggests high proportion of cryptic species. Comptes Rendus Biologies, 338(4), 266–277.
Résumé: The low level of morphometric variability and the poor phylogenetic information borne by the morpho-anatomical characters used thus far in the systematics of grey mullets (Mugilidae) emphasize the utility of molecular systematics in this family. A recent mitochondrial phylogeny of grey mullets has uncovered multiple deep lineages within several species, flagging putative cryptic species. Here, we considered that several of the deeply divergent lineages represent separate species based on either the tree topology, independent data from nuclear markers, geographic distributions, or a combination of the foregoing. By analogy with these well-documented cases, we considered other deep lineages in seven genera we focused on to represent putative cryptic species. Up to two cryptic species were thus potentially detected in the genus Chelon, three in Crenimugil (including two within the single Crenimugil seheli), two in Dajaus, one in Ellochelon, 16 in Mugil (including 13 within the single M. cephalus), two in Osteomugil, and 10 in Planiliza. Wherever possible, we kept the current species epithets to designate those lineages that unambiguously correspond to the type material, based on type locality, and we assigned arbitrary letters (sp. A, B, etc.) to the other lineages. We present a molecular diagnosis for 24 of the species analysed in this work, as well as for 25 putative cryptic species.
Mots-Clés: Chelon; clésTaxonomie moléculaire; Crenimugil; Dajaus; Ellochelon; Molecular taxonomy; Mugil; Osteomugil; Planiliza; Revision; Révision
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Durand, J. - D., Hubert, N., Shen, K. - N., & Borsa, P. (2017). DNA barcoding grey mullets. Rev. Fish. Biol. Fish., 27(1), 233–243.
Résumé: Despite the ecological and commercial importance of grey mullets (fish family Mugilidae), their taxonomy and systematics are still much debated. Reasons for this are the low level of morphometric variability and the relatively poor phylogenetic information borne by the morpho-anatomical characters used thus far in diagnosing species. Here, we evaluate the potential of DNA barcoding to accurately delineate species and assign unknown specimens to taxa in the family Mugilidae. Our reference sample consists of 257 individuals from 91 lineages characterized by their nucleotide sequences at the COI, cytochrome b, and 16S rRNA loci. These lineages correspond to 55 species according to the current taxonomy, and 36 presumed cryptic species. All known and presumed cryptic species within the 'Mugil cephalus' (n = 15) and 'M. curema' (n = 6) species complexes, as well as within genera Chelon (n = 10), Crenimugil (n = 6), Osteomugil (n = 6), and Planiliza (n = 18) were successfully recovered as distinct lineages by COI gene sequences (598 bp), demonstrating the utility of this marker to delineate species in the family Mugilidae. Inconsistencies in the labeling of sequences deposited in GenBank were ascribed to species misidentification. A proportion of these misidentifications occurred in the course of dedicated barcoding surveys, further emphasizing the need for an accurate and exhaustive reference barcoding database for Mugilidae.
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Escalas, A., Hale, L., Voordeckers, J. W., Yang, Y., Firestone, M. K., Alvarez-Cohen, L., et al. (2019). Microbial functional diversity: From concepts to applications. Ecol. Evol., 9(20), 12000–12016.
Résumé: Functional diversity is increasingly recognized by microbial ecologists as the essential link between biodiversity patterns and ecosystem functioning, determining the trophic relationships and interactions between microorganisms, their participation in biogeochemical cycles, and their responses to environmental changes. Consequently, its definition and quantification have practical and theoretical implications. In this opinion paper, we present a synthesis on the concept of microbial functional diversity from its definition to its application. Initially, we revisit to the original definition of functional diversity, highlighting two fundamental aspects, the ecological unit under study and the functional traits used to characterize it. Then, we discuss how the particularities of the microbial world disallow the direct application of the concepts and tools developed for macroorganisms. Next, we provide a synthesis of the literature on the types of ecological units and functional traits available in microbial functional ecology. We also provide a list of more than 400 traits covering a wide array of environmentally relevant functions. Lastly, we provide examples of the use of functional diversity in microbial systems based on the different units and traits discussed herein. It is our hope that this paper will stimulate discussions and help the growing field of microbial functional ecology to realize a potential that thus far has only been attained in macrobial ecology.
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Marchiori, N. C., Pariselle, A., Pereira, J., Agnese, J. - F., Durand, J. - D., & Vanhove, M. P. M. (2015). A comparative study of Ligophorus uruguayense and L. saladensis (Monogenea: Ancyrocephalidae) from Mugil liza (Teleostei: Mugilidae) in southern Brazil. Folia parasitologica, 62.
Résumé: Representatives of Ligophorus Euzet et Suriano, 1977 were found on the gills of Mugil liza Valenciennes caught in southern Brazil. They were identified as Ligophorus uruguayense Failla Siquier et Ostrowski de Nunez, 2009 and Ligophorus saladensis Marcotegui et Martorelli, 2009, even though specific identification proved to be difficult due to inconsistencies in some diagnostic features reported for these two species. Therefore, a combined morphological and molecular approach was used to critically review the validity of these species, by means of phase contrast and confocal fluorescence microscopical examination of sclerotised hard parts, and assessing the genetic divergence between L. saladensis, L. uruguayense and their congeners using rDNA sequences. The main morphological differences between the two species relate to the shape of the accessory piece of the penis and the median process of the ventral bar. The accessory piece in L. uruguayense is shorter than in L. saladensis, has a cylindrical, convex upper lobe and straight lower lobe (vs with the distal tip of the lower lobe turning away from the upper lobe in the latter species). The ventral bar has a V-shaped anterior median part in L. uruguayense (vs U-shaped in L. saladensis). The two species are suggested to be part of a species complex together with L. mediterraneus Sarabeev, Balbuena et Euzet, 2005. We recommend to generalise such comparative assessment of species of Ligophorus for a reliable picture of the diversity and diversification mechanisms within the genus, and to make full use of its potential as an additional marker for mullet taxonomy and systematics.
Mots-Clés: molecular systematics; morphology; mullet; parasite; Taxonomy
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