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Manta and devil rays are an iconic group of globally distributed pelagic filter feeders, yet their evolutionary history remains enigmatic. We employed next generation sequencing of mitogenomes for nine of the 11 recognized species and two outgroups; as well as additional Sanger sequencing of two mitochondrial and two nuclear genes in an extended taxon sampling set. Analysis of the mitogenome coding regions in a Maximum Likelihood and Bayesian framework provided a well-resolved phylogeny. The deepest divergences distinguished three clades with high support, one containing Manta birostris, Manta alfredi, Mobula tarapacana, Mobula japanica and Mobula mobular; one containing Mobula kuhlii, Mobula eregoodootenkee and Mobula thurstoni; and one containing Mobula munkiana, Mobula hypostoma and Mobula rochebrunei. Mobula remains paraphyletic with the inclusion of Manta, a result that is in agreement with previous studies based on molecular and morphological data. A fossil-calibrated Bayesian random local clock analysis suggests that mobulids diverged from Rhinoptera around 30 Mya. Subsequent divergences are characterized by long internodes followed by short bursts of speciation extending from an initial episode of divergence in the Early and Middle Miocene (19-17 Mya) to a second episode during the Pliocene and Pleistocene (3.6 Mya - recent). Estimates of divergence dates overlap significantly with periods of global warming, during which upwelling intensity - and related high primary productivity in upwelling regions - decreased markedly. These periods are hypothesized to have led to fragmentation and isolation of feeding regions leading to possible regional extinctions, as well as the promotion of allopatric speciation. The closely shared evolutionary history of mobulids in combination with ongoing threats from fisheries and climate change effects on upwelling and food supply, reinforces the case for greater protection of this charismatic family of pelagic filter feeders.

Manta and devil rays are filter-feeding elasmobranchs that are found circumglobally in tropical and subtropical waters. Although relatively understudied for most of the Twentieth century, public awareness and scientific research on these species has increased dramatically in recent years. Much of this attention has been in response to targeted fisheries, international trade in mobulid products, and a growing concern over the fate of exploited populations. Despite progress in mobulid research, major knowledge gaps still exist, hindering the development of effective management and conservation strategies. We assembled 30 leaders and emerging experts in the fields of mobulid biology, ecology, and conservation to identify pressing knowledge gaps that must be filled to facilitate improved science-based management of these vulnerable species. We highlight focal research topics in the subject areas of taxonomy and diversity, life history, reproduction and nursery areas, population trends, bycatch and fisheries, spatial dynamics and movements, foraging and diving, pollution and contaminants, and sub-lethal impacts. Mobulid rays remain a poorly studied group, and therefore our list of important knowledge gaps is extensive. However, we hope that this identification of high priority knowledge gaps will stimulate and focus future mobulid research.

DNA sequence data from mitochondrial genomes and c. 1000 nuclear exons were analysed for a complete taxon sampling of manta and devilrays (Mobulidae) to estimate a current molecular phylogeny for the family. The resulting inferences were combined with morphological information to adopt an integrated approach to resolving the taxonomic arrangement of the family. The members of the genus Manta were found to consistently nest within the Mobula species and consequently the genus Manta is placed into the synonymy of Mobula. Mobula eregoodootenkee, M. japanica and M. rochebrunei were each found to be junior synonyms of M. kuhlii, M. mobular and M. hypostoma, respectively. The mitochondrial and nuclear tree topologies were in agreement except for the placement of M. tarapacana which was basal to all other mobulids in the nuclear exon analysis, but as the sister group to the M. alfredi- M. birostris-M. mobular clade in the mitochondrial genome analysis. Results from this study are used to a revise the taxonomy for the family Mobulidae. A single genus is now recognized (where there were previously two) and eight nominal species (where there were previously 11). [ABSTRACT FROM AUTHOR]

The development of various target enrichment methods in combination with next generation sequencing techniques has greatly facilitated the use of partially degraded DNA samples in genetic studies. We employed the MYbaits target enrichment system in combination with Ion Torrent sequencing on a broad range of DNA quality, extracted from tissues obtained from both natural history archives and through various opportunistic sampling methods, to sequence the mitogenome of 11 mobulid rays and two closely related species. Mobulids are large, elusive pelagic filter feeders, for which conservation concerns have recently be raised in connection to their vulnerable life histories and increasing fishing pressure. We show that the MYbaits target enrichment method can be used to effectively sequence large parts of the mitogenome from heavily degraded DNA samples, and provide a time and cost effective alternative for genetic studies of rare and/or difficult to sample species. [ABSTRACT FROM AUTHOR]

An updated checklist of manta and devil rays (family Mobulidae) occurring in waters of the Azores archipelago is given based on new data from underwater images and on the re-evaluation of previous citations for the region. There are, at least, three species of mobulids occurring in the region, possibly four: giant manta Manta birostris; Chilean devil ray Mobula tarapacana; and one or both of the giant devil ray Mobula mobular/spinetail devil ray Mobula japanica species complex. These findings have direct implications for the known ranges of all these species and for the conservation of their North Atlantic populations. [ABSTRACT FROM PUBLISHER]

The Mobulidae are zooplanktivorous elasmobranchs comprising two recognized species of manta rays ( Manta spp.) and nine recognized species of devil rays ( Mobula spp.). They are found circumglobally in tropical, subtropical and temperate coastal waters. Although mobulids have been recorded for over 400 years, critical knowledge gaps still compromise the ability to assess the status of these species. On the basis of a review of 263 publications, a comparative synthesis of the biology and ecology of mobulids was conducted to examine their evolution, taxonomy, distribution, population trends, movements and aggregation, reproduction, growth and longevity, feeding, natural mortality and direct and indirect anthropogenic threats. There has been a marked increase in the number of published studies on mobulids since c. 1990, particularly for the genus Manta, although the genus Mobula remains poorly understood. Mobulid species have many common biological characteristics although their ecologies appear to be species-specific, and sometimes region-specific. Movement studies suggest that mobulids are highly mobile and have the potential to rapidly travel large distances. Fishing pressure is the major threat to many mobulid populations, with current levels of exploitation in target fisheries unlikely to be sustainable. Advances in the fields of population genetics, acoustic and satellite tracking, and stable-isotope and fatty-acid analyses will provide new insights into the biology and ecology of these species. Future research should focus on the uncertain taxonomy of mobulid species, the degree of overlap between their large-scale movement and human activities such as fisheries and pollution, and the need for management of inter-jurisdictional fisheries in developing nations to ensure their long-term sustainability. Closer collaboration among researchers worldwide is necessary to ensure standardized sampling and modelling methodologies to underpin global population estimates and status. [ABSTRACT FROM AUTHOR]

Abstract: This paper provides some of the only fisheries and quantitative biological data for the Mobulidae (manta and devil rays), a group of large pelagic species that are widely distributed in tropical and warm temperate waters. The data were derived from 409 mobulids that were taken as bycatch of drift gillnet fisheries for the skipjack tuna Katsuwonus pelamis and subsequently examined at fish landing sites in Indonesia. The most abundant of the five species was Mobula japanica (∼50%), followed by Mobula tarapacana (∼24%), Manta birostris (∼14%), Mobula thurstoni (9%) and Mobula cf kuhlii (2%). The four most abundant species were represented by a wide size range of each species and, in the case of Mobula japanica, by embryos, neonates and fully mature individuals. The disc width at maturity (DW50) of males, derived from the proportion of males at each size class with fully calcified claspers, ranged from 1538mm for Mobula thurstoni to 3752mm for M. birostris. As the claspers of males become calcified over a relatively narrow size range, the process of maturation is presumably relatively rapid. There is an increasing demand for various body parts of mobulids. Branchial filter plates, which are used for traditional Chinese medicines, are the most valuable, fetching as much as 30 $US a kilo (dry weight). The skins are dried and deep fried and the flesh salted and dried and these are used for human consumption, while cartilage is dried for export as a filler for shark-fin soup. The very low fecundity of the large and probably long-lived mobulid rays make the stocks of their species particularly susceptible to further increases in fishing. [Copyright &y& Elsevier]

This study comprises the first record of a juvenile Giant Devil Ray specimen for Rio de Janeiro, Southeastern Brazil, and its metal and metalloid contents. A scientometric assessment was also performed for the Manta and Mobula genera. Only five records were found, and only As, Cd, Pb, Hg, Pt, Pd and Rh have been assessed. All studies but one concerned human consumption. A significant knowledge gap on metal and metalloid ecotoxicology for mobulid rays is noted, indicating the emergence of a new field of research that th may be applied for wildlife conservation and management in response to anthropogenic contamination. Our study is also the first to provide Al, Cr, Cu, Fe, Mn, Sr, Ti, V and Zn contents for muscle, liver, brain and kidney for a mobulid ray and one of the scarce reports concerning As, Cd, Hg and Pb in muscle, liver and kidney. • First record of a Giant Devil Ray for Rio de Janeiro, Brazil • First report for Al, Cr, Cu, Fe, Mn, Sr, Ti, V and Zn in a mobulid ray • Only five elemental studies for the Manta and Mobula genera are available. • Only As, Cd, Pb, Hg, Pt, Pd and Rh have been assessed to date. • A significant knowledge gap concerning concerning elemental ecotoxicology for mobulids is noted. [ABSTRACT FROM AUTHOR]