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Rays of the superorder Batoidea comprise the most diverse group of chondrichthyans in terms of valid species and morphological disparity. Up to the present little agreement is observed in studies based on morphological and molecular data focused on uncovering the interrelationships within Batoidea. Morphology-based phylogenies of batoids have not included characters related to the afferent branchial arteries, and little is known about the variation in this anatomical complex in rays. Herein, representatives of 32 genera from 19 families currently recognized of rays were examined as well as some shark taxa. Seven new characters are proposed and tested in two different analyses, one on their own and in the other they were added to the morphological data matrix of the most recent analysis of interrelationships within Batoidea. The arrangement of afferent branchial arteries differs mainly among orders and families of batoids. The absence of a common trunk from which the three posteriormost afferent arteries branch is interpreted as a synapomorphy for Myliobatiformes and the presence of a coronary cranial artery as an autapomorphy for Mobula hypostoma. A close spatial relationship between the second and third afferent arteries within the common branch from the ventral aorta is proposed as a synapomorphy for Rajiformes with a secondary modification in Sympterygia. Data about patterns in afferent branchial arteries in additional taxa such as Squaliformes and Chimaeriformes are needed to better understand the evolution of this character complex among chondrichthyans.

In this paper, inspired by the external morphology of a manta ray (Mobula alfredi), four chimerical wing planforms are designed to assess its gliding performance. The planforms possess an arbitrary combination of extra hydrodynamic features like tubercles at the leading edge (L.E.) and trailing edge (T.E.) inspired by humpback whale's flippers and flukes, respectively, as longitudinal ridges inspired by whale shark's economy. In addition, another planform is designed to investigate the possible effects of manta ray's injuries (geometric deficiency) generated by predator's attacks or boat strikes on its locomotion (gliding) performance. In this regard, turbulent flow physics involved in the problem is numerically simulated at different angles of attack (AoA). High Reynolds number, 106, corresponding to the swimming of a juvenile manta ray at an average speed equals one m/s. The results show that the manta ray-inspired planform with L.E. undulations exhibits a superior performance at high AoAs than its other counterpart variants. In addition, the results demonstrate that injuries on the manta ray's body can noticeably modify hydrodynamics and, as a result corresponding hydrodynamical forces and moments acting on the swimming animal in the gliding phase.

Purpose Purpose of this paper are Real power loss reduction, voltage stability enhancement and minimization of Voltage deviation. Design/methodology/approach In HLG approach as per Henry gas law sum of gas dissolved in the liquid is directly proportional to the partial pressure on above the liquid. Gas dissolving in the liquid which based on Henry gas law is main concept to formulate the proposed algorithm. Populations are divided into groups and all the groups possess the similar Henry constant value. Exploration and exploitation has been balanced effectively. Ranking and position of the worst agents is done in order to avoid the local optima. Then in this work Mobula alfredi optimization (MAO) algorithm is projected to solve optimal reactive power problem. Foraging actions of Mobula alfredi has been imitated to design the algorithm. String foraging, twister foraging and backward roll foraging are mathematically formulated to solve the problem. In the entire exploration space the Mobula alfredi has been forced to discover new regions by assigning capricious position. Through this approach, exploration competence of the algorithm has been improved. In all iterations, the position of the Mobula alfredi has been updated and replaced with the most excellent solution found so far. Exploration and exploitation capabilities have been maintained sequentially. Then in this work balanced condition algorithm (BCA) is projected to solve optimal reactive power problem. Proposed BCA approach based on the conception in physics- on the subject of the mass; incoming, exit and producing in the control volume. Preliminary population has been created based on the dimensions and number of particles and it initialized capriciously in the exploration space with minimum and maximum concentration. Production control parameter and Production probability utilized to control the exploration and exploitation. Findings Proposed Henry's Law based -soluble gas optimization (HLG) algorithm, Mobula alfredi optimization (MAO) algorithm and BCA are evaluated in IEEE 30 bus system with L-index (Voltage stability) and also tested in standard IEEE 14, 30, 57, 118, 300 bus test systems without L- index. Real power loss minimization, voltage deviation minimization, and voltage stability index enhancement has been attained. Originality/value For the first time Henry's Law based -soluble gas optimization (HLG) algorithm, Mobula alfredi optimization (MAO) algorithm and BCA is projected to solve the power loss reduction problem.

Mutualism is a form of symbiosis whereby both parties benefit from the relationship. An example is cleaning symbiosis, which has been observed in terrestrial and marine environments. The most recognized form of marine cleaning symbiosis is that of cleaner fishes and their clients.Cleaner species set up cleaning stations on the reef, and other species seek out their services. However, it is not well understood how the presence of cleaning stations influence movements of large highly mobile species. We examined the role of cleaning stations as a driver of movement and habitat use in a mobile client species.Here, we used a combination of passive acoustic telemetry and in‐water surveys to investigate cleaning station attendance by the reef manta ray Mobula alfredi. We employed a novel approach in the form of a fine‐scale acoustic receiver array set up around a known cleaning area and tagged 42 rays. Within the array, we mapped structural features, surveyed the distribution of cleaner wrasse, and observed the habitat use of the rays.We found manta ray space use was significantly associated with blue‐streak cleaner wrasse Labroides dimidiatus distribution and hard coral substrate. Cleaning interactions dominated their habitat use at this site, taking precedence over other life history traits such as feeding and courtship.This study has demonstrated that cleaning symbiosis is a driver for highly mobile, and otherwise pelagic, species to visit inshore reef environments. We suggest that targeted and long‐term use of specific cleaning stations reflects manta rays having a long‐term memory and cognitive map of some shallow reef environments where quality cleaning is provided. We hypothesize that animals prefer cleaning sites in proximity to productive foraging regions., This study investigates the role of mutualism in determining site selection in marine megafauna. The aim was to determine the role of cleaning stations as a driver of movement and habitat use in a mobile client species. Through a combination of in‐water observations and a novel application of fine‐scale passive acoustic tracking, we demonstrated that cleaning symbiosis is a driver for highly mobile, and otherwise pelagic species to visit inshore reef environments. We suggest that targeted and long‐term use of specific cleaning stations reflects manta rays having a long‐term memory and cognitive map of some shallow reef environments where quality cleaning is provided. We hypothesize that animals preference cleaning sites in proximity to productive foraging regions.

Globally, reef manta rays (Mobula alfredi) are in decline and are particularly vulnerable to exploitation and disturbance at aggregation sites. Here, passive acoustic telemetry and a suite of advanced oceanographic technologies were used for the first time to investigate the fine‐scale (5‐min) influence of oceanographic drivers on the visitation patterns of 19 tagged M. alfredi to a feeding aggregation site at Egmont Atoll in the Chagos Archipelago. Boosted regression trees indicate that tag detection probability increased with the intrusion of cold‐water bores propagating up the atoll slope through the narrow lagoon inlet during flood tide, potentially transporting zooplankton from the thermocline. Tag detection probability also increased with warmer near‐surface temperature close to low tide, with near‐surface currents flowing offshore, and with high levels of backscatter (a proxy of zooplankton biomass). These combinations of processes support the proposition that zooplankton carried from the thermocline into the lagoon during the flood may be pumped back out through the narrow inlet during an ebb tide. These conditions provide temporally limited feeding opportunities for M. alfredi, which are tied on the tides. Results also provide some evidence of the presence of Langmuir Circulation, which transports and concentrates zooplankton, and may partly explain why M. alfredi occasionally remained at the feeding location for longer than that two hours. Identification of these correlations provides unique insight into the dynamic synthesis of fine‐scale oceanographic processes which are likely to influence the foraging ecology of M. alfredi at Egmont Atoll, and elsewhere throughout their range.

Little is known about the extent of genetic connectivity along continuous coastlines in manta rays, or whether site visitation is influenced by relatedness. Such information is pertinent to defining population boundaries and understanding localized dispersal patterns and behaviour. Here, we use 3057 genome-wide single-nucleotide polymorphisms (SNPs) to evaluate population genetic structure and assess the levels of relatedness at aggregation sites of reef manta rays (Mobula alfredi) in southern Mozambique (n = 114). Contrary to indications of limited dispersal along the southern Mozambican coastline inferred from photo-identification and telemetry studies, our results show no evidence of population structure (non-significant F(ST)

Nine specimens (one female and eight males, all juveniles) of lesser devil ray, Mobula hypostoma (Bancroft, 1831), were caught in the southwest Gulf of Mexico. These specimens represent the first record of the species in the Mexican waters. The disk width ranged between 552 and 773 mm. Morphometrics data are consistent with previously published records. Because of the number of specimens captured, we suggest that it is not a rare species in the southwest Gulf of Mexico.

Mobulid populations are declining on a global scale as a result of both targeted fisheries and indirect anthropogenic threats. In order to implement effective conservation strategies for species of this taxa, it is crucial that movement patterns at a range of spatiotemporal scales are defined. To gain insight into such patterns, we deployed a combination of acoustic (n = 21) and satellite (n = 12) tags on reef manta rays Mobula alfredi in the British Indian Ocean Territory Marine Protected Area (BIOT MPA) annually from 2013 through 2016. An extensive array of acoustic receivers (n = 52) were deployed across the archipelago to record the movements of mantas throughout the MPA. Data revealed large individual variation in horizontal movement patterns, ranging from high local site fidelity (200 km) around the entire MPA. Depth time-series data recorded vertical movement patterns consistent with other epipelagic elasmobranch species, including oscillatory diving and deep dives to greater than 500 m. Though no individuals were directly recorded departing the MPA throughout the study, the gaps in detections and estimated travel speeds documented here indicate that movement of individuals outside of the BIOT MPA cannot be discounted. Collectively, our data suggests that, with effective enforcement, the current size of the BIOT MPA is providing substantial protection to its reef manta ray population. Characterization of movement patterns across ontogenetic classes, however, is required to fully characterize the spatial ecology of this species and ensure protection across all cohorts of the population.

Mobula mobular, a mobulid species once considered a Mediterranean Sea endemic, has received its common name “giant devil ray” based on repeated misidentifications of oceanic manta rays, Mobula birostris, that had strayed into the Mediterranean, where they had never been reported from before. Based on the maximum known size (350 cm disc width) of M. mobular, when compared to some of its congenerics, the giant devil ray is not giant at all. A recent revision of the phylogeny and taxonomy of genus Mobula, which included, amongst other things, the decision to consider the circumtropical spinetail devil ray M. japanica a junior synonym of M. mobular, has caused the latter species to become circumglobal, and the only known mobulid with a tail spine. As a consequence, it is here recommended that the common name of M. mobular be “spinetail devil ray”.

The known distribution of manta rays in Australian waters is patchy, with records primarily centred around tourism hotspots. We collated 11,614 records of Mobula alfredi from photo-ID databases (n = 10,715), aerial surveys (n = 378) and online reports (n = 521). The study confirms an uninterrupted coastal distribution from north of 26 degrees S and 31 degrees S on the west and east coasts, respectively. More southerly M. alfredi records relate to warm-water events with a southernmost extent at 34 degrees S. Coastal sightings of Mobula birostris were rare (n = 32), likely reflecting a preference for offshore waters, but encompass a wider latitudinal extent than M. alfredi of 10-40 degrees S.

Made available in DSpace on 2020-12-10T19:45:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-03 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Inter-ministerial Secretariat for Marine Resources (SECIRM) UFRPE Save Our Seas Foundation Marine Conservation Action Fund Oceanos Vivientes A.C. Information on elasmobranch mating behavior is limited. For batoids, observations of mating behavior in the wild are available only for a few species. We present video documentation of new cases of mating behavior for three species of myliobatiform rays. On July 20, 2013, a group of six cownose rays (Rhinoptera bonasus) were observed mating in shallow coastal waters off New Jersey. On August 19, 2014, two whitespotted eagle rays (Aetobatus narinari) were observed mating in Harrington Sound, Bermuda. In both cases, all stages of the mating sequence described in the literature were observed: 1) close following, 2) pre-copulatory biting, 3) copulation/insertion, 4) resting, and 5) separation. This is consistent with observations of mating behavior for whitespotted eagle rays and Javanese cownose rays (Rhinoptera javanica) in captivity. This is the first time a complete mating sequence has been documented in the wild for either species. Additionally, on May 18, 2015, a group of four bentfin devil rays (Mobula thurstoni) were observed engaging in pre-mating behaviors at the Archipelago of Saint Peter and Saint Paul, Brazil and is the first documented account of mating behavior for this species. In all three cases, we noted that the female was considerably darker in color than the males, which may be evidence of a visual pre-copulation cue, as seen in other marine fishes. The similarity of the behaviors presented here and those observed in other species (e.g., M. birostris, Hypanus americanus, and Taeniurops meyeni) suggests mating behavior may be highly conserved among batoids. Florida Atlantic Univ, Harbor Branch Oceanog Inst, Ft Pierce, FL 34946 USA New England Aquarium, Anderson Cabot Ctr Ocean Life, Cent Wharf, Boston, MA 02110 USA Oceanos Vivientes AC, Cerrada Monserrat 9, Mexico City 04380, DF, Mexico Univ Massachusetts, Dept Environm Conservat, 160 Holdsworth Way, Amherst, MA 01003 USA Univ Estadual Paulista Julio Mesquita, Inst Biociencias, Campus Litoral Paulista, Sao Paulo, SP, Brazil Univ Estadual Paulista Julio Mesquita, Inst Biociencias, Campus Litoral Paulista, Sao Paulo, SP, Brazil

Mobula munkiana Notarbartola di Sciara, 1987. Pygmy Devil Ray or Munk���s Devil Ray. 110 cm (43.3 in) DW (Couturier et al. 2012). Todos Santos (23��24.6���N, 110��13.8���W), southern Baja California (John Snow, pers. comm. to M.L.); Gulf of California to Peru, Islas Gal��pagos and other offshore islands (Robertson and Allen 2008). Depth: surface to 30 m (98 ft) (Weigman 2016), and to benthos in nearshore waters (Smith et al. 2009)., Published as part of Love, Milton S., Bizzarro, Joseph J., Cornthwaite, Maria, Frable, Benjamin W. & Maslenikov, Katherine P., 2021, Checklist of marine and estuarine fishes from the Alaska-Yukon Border, Beaufort Sea, to Cabo San Lucas, Mexico, pp. 1-285 in Zootaxa 5053 (1) on page 30, DOI: 10.11646/zootaxa.5053.1.1, http://zenodo.org/record/5578008, {"references":["Couturier, L. I. E., Marshall, A. D., Jaine, F. R. A., Kashiwagi, T., Pierce, S. J., Townsend, K. A., Weeks, S. J., Bennett, M. B. & Richardson, A. J. (2012) Biology, ecology and conservation of the Mobulidae. Journal of Fish Biology, 80, 1075 - 1119. https: // doi. org / 10.1111 / j. 1095 - 8649.2012.03264. x","Robertson, D. R. & Allen, G. R. (2008) Shorefishes of the Tropical Eastern Pacific: an Information System. Version 1.0 (2008). Smithsonian Tropical Research Institute, Balboa.","Smith, W. D., Bizzarro, J. J. & Cailliet, G. M. (2009) The artisanal elasmobranch fishery of Baja California, Mexico: characteristics and management considerations. Ciencias Marinas, 35, 209 - 236. https: // doi. org / 10.7773 / cm. v 35 i 2.1534"]}

Mobula tarapacana (Philippi, 1893). Chilean Devil Ray or Sicklefin Devil Ray. To 3.7 m (12.1 ft) DW (Compagno and Last in Carpenter and Niem 1999). Circumglobal; western Pacific Ocean north to northern Japan (Aonuma and Yoshino in Nakabo 2002); southern Baja California (McEachran and Notarbartolo di Sciara in Fischer et al. 1995) to Chile (Peque��o 1989), including Gulf of California (McEachran and Notarbartolo di Sciara in Fischer et al. 1995). Depth: surface to over 2,000 m (6,560 ft) (min.: Robertson and Allen 2002; max. Jones et al. 2020)., Published as part of Love, Milton S., Bizzarro, Joseph J., Cornthwaite, Maria, Frable, Benjamin W. & Maslenikov, Katherine P., 2021, Checklist of marine and estuarine fishes from the Alaska-Yukon Border, Beaufort Sea, to Cabo San Lucas, Mexico, pp. 1-285 in Zootaxa 5053 (1) on page 30, DOI: 10.11646/zootaxa.5053.1.1, http://zenodo.org/record/5578008, {"references":["Carpenter, K. E. & Niem, V. H. (Eds.). (1999) The Living Marine Resources of the Western Central Pacific. Volume 3. Batoid Fishes, Chimaeras and Bony Fishes Part 1 (Elopidae to Linophrynidae). Volume 4. Bony Fishes Part 2 (Mugilidae to Carangidae). FAO, Rome.","Nakabo, T. (Ed.). (2002) Fishes of Japan with Pictorial Keys to the Species. Tokai University Press, Tokyo.","Fischer, W., Krupp, F., Schneider, W., Sommer, C., Carpenter, K. E. & Niem, V. H. (1995) Guia FAO para la identificacion para los fines de la pesca. Pacifico centro-oriental. Volume II, Vertebrados, Parte 1. Volume III, Vertebrados, Parte 2. FAO, Rome.","Pequeno R., G. (1989) Peces de Chile lista sistematica revisada y comentada. Revista de Biologia Marina y Oceanografia, 24, 1 - 132.","Robertson, D. R. & Allen, G. R. (2002) Shorefishes of the tropical eastern Pacific: an information system. CD-ROM. Smithsonian Tropical Research Institute, Balboa, Panama.","Jones, C. M., Driggers II, W. B., Hannan, K. M., Hoffmayer, E. R., Jones, L. M. & Raredon, S. J. (2020) An annotated checklist of the chondrichthyan fishes in habiting the northern Gulf of Mexico Part 1: Batoidea. Zootaxa, 2803, 281 - 315. https: // doi. org / 10.11646 / zootaxa. 4803.2.3"]}

Mobula mobular (Bonnaterre, 1788). Giant Devilray or Spinetail Devil Ray. Notarbartolo di Sciara et al. (2020) note that recent taxonomic changes among the Mobulidae have made the name Giant Devilray obsolete and suggest that Spinetail Devil Ray is more accurate. To at least 5.2 m (17.1 ft) DW (Last et al. 2016). Circumglobal; western Pacific Ocean north to Korea and northern Japan (as Mobula japonica, Aonuma and Yoshino in Nakabo 2002); central California to Peru (Ebert 2003), including Gulf of California (Galv��n-Maga��a et al. 1996). Depth: surface to at 700 m (2,296 ft) (min.: Ebert 2003; max.: Weigmann 2016). The Mobula thurstoni reported by MacGinitie (1947) from Laguna Beach, southern California is likely M. mobular (Notarbartolo di Sciara 1987). We follow Poortvliet et al. (2015) and Last et al. (2016) in synonymizing Mobula japanica (M��ller & Henle, 1841) with this species., Published as part of Love, Milton S., Bizzarro, Joseph J., Cornthwaite, Maria, Frable, Benjamin W. & Maslenikov, Katherine P., 2021, Checklist of marine and estuarine fishes from the Alaska-Yukon Border, Beaufort Sea, to Cabo San Lucas, Mexico, pp. 1-285 in Zootaxa 5053 (1) on page 30, DOI: 10.11646/zootaxa.5053.1.1, http://zenodo.org/record/5578008, {"references":["Notarbartolo di Sciara, G., Stevens, G. & Fernando, D. (2020) The giant devil ray Mobula mobular (Bonnaterre, 1788) is not giant, but it is the only spinetail devil ray. Marine Biodiversity Records, 13, 4. https: // doi. org / 10.1186 / s 41200 - 020 - 00187 - 0","Last, P. R., Naylor, G. J. P. & Manjaji-Matsumoto, B. M. (2016 a) A revised classification of the family Dasyatidae (Chondrichthyes: Myliobatiformes) based on new morphological and molecular insights. Zootaxa, 4139, 345 - 368. https: // doi. org / 10.11646 / zootaxa. 4139.3.2","Nakabo, T. (Ed.). (2002) Fishes of Japan with Pictorial Keys to the Species. Tokai University Press, Tokyo.","Ebert, D. A. (2003) Sharks, Rays, and Chimaeras of California. University of California Press, Berkeley.","Galvan-Magana, F., Abitia-Cardenas, L. A., Rodriguez-Romero, J., Perez-Espana, H. & Chavez-Ramos, H. (1996) Systematic list of the fishes from Cerralvo Island, Baja California Sur, Mexico. Ciencias Marinas, 22, 295 - 311.","Weigmann, S. (2016) Annotated checklist of the living sharks, batoids and chimaeras (Chondrichthyes) of the world, with a focus on biogeographical diversity. Journal of Fish Biology, 88, 837 - 1037. https: // doi. org / 10.1111 / jfb. 12874","MacGinitie, G. E. (1947) Notes on the devilfish, Mobula lucasana, and its parasites. Copeia, 1947, 276 - 278.","Poortvliet, M., Olsen, J. L., Croll, D. A., Bernardi, G., Newton, K., Kollias, S., O'Sullivan, J., Fernando, D., Stevens, G., Galvan Magana, F., Seret, B., Wintner, S. & Hoarau, G. (2015) A dated molecular phylogeny of manta and devil rays (Mobulidae) based on mitogenome and nuclear sequences. Molecular Phylogenetics and Evolution, 83, 72 - 85. https: // doi. org / 10.1016 / j. ympev. 2014.10.012"]}

Mobula birostris (Walbaum, 1792). Giant Manta or Manta. To at least 7 m (23 ft) DW (Weigman 2016), and unconfirmed to 9.1 m (29.8 ft) DW (Last and Stevens 2009). Circumglobal in warm waters mainly between 40��N and 40��S (Last et al. 2016); western Pacific Ocean north to Okinawa (Aonuma and Yoshino in Nakabo 2002); Santa Barbara, southern California (Ebert 2003) to Peru (12��S) (Moreno and Gonzalez-Pestana 2017), including Gulf of California (McEachran and Notarbartolo di Sciara in Fischer et al. 1995), and Islas Gal��pagos (Grove and Lavenberg 1997); sighting (unverifiable) reported from Prince Willam Sound, Alaska (Karinen et al. 1985). Pelagic; depth: surface to at least 1,000 m (3,280 ft) (Weigman 2016)., Published as part of Love, Milton S., Bizzarro, Joseph J., Cornthwaite, Maria, Frable, Benjamin W. & Maslenikov, Katherine P., 2021, Checklist of marine and estuarine fishes from the Alaska-Yukon Border, Beaufort Sea, to Cabo San Lucas, Mexico, pp. 1-285 in Zootaxa 5053 (1) on page 29, DOI: 10.11646/zootaxa.5053.1.1, http://zenodo.org/record/5578008, {"references":["Last, P. R. & Stevens, J. D. (2009) Sharks and Rays of Australia. Second Edition. CSIRO, Melbourne.","Last, P. R., Naylor, G. J. P. & Manjaji-Matsumoto, B. M. (2016 a) A revised classification of the family Dasyatidae (Chondrichthyes: Myliobatiformes) based on new morphological and molecular insights. Zootaxa, 4139, 345 - 368. https: // doi. org / 10.11646 / zootaxa. 4139.3.2","Nakabo, T. (Ed.). (2002) Fishes of Japan with Pictorial Keys to the Species. Tokai University Press, Tokyo.","Ebert, D. A. (2003) Sharks, Rays, and Chimaeras of California. University of California Press, Berkeley.","Moreno, B. & Gonzalez-Pestana, A. (2017) Southernmost record of the giant manta ray Mobula birostris (Walbaum, 1792) in the eastern Pacific. Marine Biodiversity Records, 10 (27). https: // doi. org / 10.1186 / s 41200 - 017 - 0130 - 1","Fischer, W., Krupp, F., Schneider, W., Sommer, C., Carpenter, K. E. & Niem, V. H. (1995) Guia FAO para la identificacion para los fines de la pesca. Pacifico centro-oriental. Volume II, Vertebrados, Parte 1. Volume III, Vertebrados, Parte 2. FAO, Rome.","Grove, J. S. & Lavenberg, R. J. (1997) The Fishes of the Galapagos Islands. Stanford University Press, Stanford.","Karinen, J. F., Wing, B. L. & Straty, R. R. (1985) Records and sightings of fish and invertebrates in the eastern Gulf of Alaska and oceanic phenonmenon related to the 1983 El Nino event. In: Wooster, W. S. & Fluherty, D. L. (Eds.), El Nino North: Nino Effects in the Eastern Subarctic Pacific Ocean. Washington Sea Grant Program, University of Washington, Seattle."]}

Data from 369 sightings of mobulid rays from St Helena Island, Cardno and Bonaparte seamounts in the South Atlantic are summarised. 50 % (183) of sightings were observed from a boat, 48 % (176) of sightings were encountered in water, of which 95 % (168) were whilst actively scuba diving. 2 % (10) of mobulid ray sightings were observed from land. Sightings data indicate that the Chilean devil ray Mobula tarapacana(Philippi, 1892) is a frequent visitor to St Helena and is present all year. We document the first photographic evidence of the presence of oceanic manta,Mobula birostris(Walbaum, 1792) at St Helena. Two solitary individuals were photographed off the north coast of St Helena in June 2018. These sightings confirm previous unverified reports on the species occurrence and extend the known distribution range ofM. birostrisin the open South Atlantic Ocean to 16°S.

Manta rays are marine planktivorous elasmobranchs that are distributed worldwide and highly susceptible to overexploitation. Although they are legally protected in Brazil since March 2013, incidental and intentional captures still occur. The sharp population decline following the intensification of targeted fisheries and bycatch highlights the urgent need of manta ray protection. This study provides information on several threats to manta rays (Mobula birostris and M. cf. birostris) in Brazil, including the frequency and geographic extent of the occurrences and their fishing and entanglement with fishing gear. We analysed photo/video records, and the scientific literature reporting mobulids incidence and focused on events of entanglement in fishing gear, intentional and incidental caught of manta rays, obtained from 2000 to 2020. From a total of 270 records of manta rays’ occurrences, 70 displayed wounds from anthropogenic activities, including 29 lethal records. Most of the injured individuals were recorded in the State of Sao Paulo (31.4%; n = 22), followed by Pernambuco (20.0%; n = 14), Rio de Janeiro (10.0%; n = 7), Bahia (8.6%; n = 6), Rio Grande do Norte (7.1%; n = 5), and Espirito Santo (5.7%; n = 4). Despite outnumbered, all manta rays’ occurrences in the states of Rio Grande do Norte, Ceara, Sergipe, Para, Piaui and Santa Catarina showed individuals either captured by fishers, with body scars or dragging fishing artefacts. The majority (61.4%) of injured individuals were recorded after the national protected status was implemented to the family Mobulidae, and all injuries observed were consequences of anthropogenic action. Our results highlight the diverse sources of threat and injuries patterns for manta rays in the nationwide territory and underscore the urgent need for monitoring fishing impacts and promoting effective enforcement of the national regulation for the protection of manta rays in Brazil.

Despite being among the largest and most charismatic species in the marine environment, considerable gaps remain in our understanding of the behavioural ecology of manta rays (Mobula alfredi, M. birostris). Manta rays are often sighted in association with an array of smaller hitchhiker fish species, which utilise their hosts as a sanctuary for shelter, protection, and the sustenance they provide. Species interactions, rather than the species at the individual level, determine the ecological processes that drive community dynamics, support biodiversity and ecosystem health. Thus, understanding the associations within marine communities is critical to implementing effective conservation and management. However, the underlying patterns between manta rays, their symbionts, and other hitchhiker species remain elusive. Here, we explore the spatial and temporal variation in hitchhiker presence with M. alfredi and M. birostris throughout the Maldives and investigate the factors which may influence association using generalised linear mixed effects models (GLMM). For the first time, associations between M. alfredi and M. birostris with hitchhiker species other than those belonging to the family Echeneidae are described. A variation in the species of hitchhiker associated with M. alfredi and M. birostris was identified, with sharksucker remora (Echeneis naucrates) and giant remora (Remora remora) being the most common, respectively. Spatiotemporal variation in the presence of manta rays was identified as a driver for the occurrence of ephemeral hitchhiker associations. Near-term pregnant female M. alfredi, and M. alfredi at cleaning stations, had the highest likelihood of an association with adult E. naucrates. Juvenile E. naucrates were more likely to be associated with juvenile M. alfredi, and a seasonal trend in E. naucrates host association was identified. Remora were most likely to be present with female M. birostris, and a mean number of 1.5 ± 0.5 R. remora were observed per M. birostris. It is hoped these initial findings will serve as the basis for future work into the complex relationships between manta rays and their hitchhikers.

Manta rays (Mobula birostris, Mobula. cf. birostris, andMobula alfredi), the largest mobulid rays, are subjected to exploitation and overfishing in certain parts of the world. Tourism has been supported as a sustainable alternative for the conservation of the species, and a potential source of economic spillover to local populations. Nevertheless, the effects of tourism over these highly social animals remains unknown. Manta rays aggregate at three sites in Mexico: Oceanic manta rays (M. birostris)in The Revillagigedo Archipelago and Banderas Bay in the Pacific. Caribbean manta rays (M. cf. birostris) around Isla Contoy National Park in the Caribbean. We analyzed the behavior of manta rays using video data collected by local researchers and tourism operators to determine how diver behaviors and techniques (SCUBA and free diving) affect them. Diver activities were grouped into passive and active categories. We described 16 behaviors and grouped them into four behavioral states: Directional, erratic, attraction and evasion to divers. We modeled the sequence of behaviors exhibited by manta rays via first order Markov chains. Our models accounted for passive and active diver behavior when modeling the changes in manta behavior. Manta rays in Banderas Bay and Revillagigedo displayed a higher frequency of erratic behaviors than at Isla Contoy, while Banderas Bay manta rays transitioned to evasion behaviors more often. Manta rays responded similarly in both sites to active divers. At freediving sites, manta rays from Isla Contoy displayed evasion less frequently than at Banderas Bay. Changes in manta ray behavior were similar for both sites, but mantas in Banderas Bay transitioned to evasion more with active divers. The increased food availability for Isla Contoy manta rays could be the reason for the reduced response toward divers in this site. The existence of additional stressors such as both traffic in Banderas Bay could be causing the mantas in this site to respond more frequently to active divers. This study, the first of its kind in oceanic and Caribbean manta rays, highlights that regulations and the use of best practices are vital for achieving longer and less disturbing encounters for both manta rays and divers.

The longhorned pygmy devil ray Mobula eregoodoo (Cantor, 1849), formerly known as Mobula eregoodootenkee (Bleeker, 1859), is a small mobulid with a disc reaching a maximum width of 1.3 m, widely ranging in tropical and subtropical latitudes across the Indian Ocean, the Indo-Pacific region, and the western Pacific Ocean. A recently emerged opportunity to examine several (n = 47) M. eregoodoo specimens bycaught in bather protection gillnets off New South Wales, Australia, together with new information assembled from other areas of its range, now allows for a redescription of the species, which was incompletely described in the past because of a paucity of specimens. Based on the morphometric, morphological, ecological, and behavioural elements presented here, corroborated by recent genetic investigations, we argue that M. eregoodoo (Cantor, 1849) is a valid species, distinct from shorthorned pygmy devil ray Mobula kuhlii (Muller & Henle, 1841). These findings are contrary to a recent revision of Mobula, where it was assessed as a synonym of M. kuhlii. The accuracy of taxonomic assessments underpins the effectiveness of species conservation, particularly when direct exploitation or bycatch in various fisheries needs to be managed for sustainability. Failing to recognize that two similar-looking species are distinct, such as M. eregoodoo and M. kuhlii, creates uncertainties that could result in mismanagement and underestimating local and global threats of extinction.

This study presents new information on tentaculariid trypanorhynchs from the Indo-Pacific region around Bali, Indonesia. Two new tentaculariid species, Nybelinia balinensis n. sp. and N. mobulicola n. sp., are described from the stomach of their myliobatid host Mobula japanica (Muller & Henle). Nybelinia balinensis n. sp. is a large-sized tentaculariid (scolex length, 6766–10,991). It can be distinguished from its congeners by a falcate metabasal armature, a unique basal armature of four rows of triangular shaped hooks, craspedote proglottids, and testes arranged in multiple layers in two separate lateral fields. N. mobulicola n. sp. can be characterized by short tentacles of 25 rows of hooks and 60 testes not reaching posterior to the ovary. A combination of a shorter basal armature of uncinate hooks without anterior extension of the base and fewer metabasal uncinate hooks with anterior extension of the base distinguishes it from N. lingualis (Cuvier, 1817). It differs from N. balinensis n. sp. in the possession of uncinate rather triangular shaped basal hooks. The Nybelinia Poche, 1926 fauna of M. japanica is highly specific, in line with a unique trypanorhynch fauna earlier described for the devil rays. This reflects their unique position as oceanic plankton feeders within the marine food web.

Research into the movement ecology of terrestrial and marine animals is growing globally, especially for threatened species. Understanding how far an animal can move and the extent of its range can inform conservation planning and management. On the east coast of Australia, reef manta rays Mobula alfredi are the subject of a photographic identification study, Project Manta. In June 2018, videos of reef manta rays from the SS Yongala (19.31° S, 147.62° E), were submitted to the Project Manta east coast sightings database. The videos were of two individuals previously identified from North Stradbroke Island (27.42° S, 153.55° E), about 1150 km to the south of the SS Yongala. This represents the greatest point-to-point distance travelled by individual M. afredi and extends the latitudinal range for this sub-population on the east coast. This study highlights that citizen science input can provide valuable data to address knowledge gaps in the distribution and population range of marine species. Knowledge of the 1000+ km range movement potential of individual M. alfredi, highlights the possibility that regional sub-populations may span jurisdictional zones of more countries than previously considered likely, complicating conservation management of this species.

We determined stable-isotope ratios for replicate muscle tissues in 13 gravid Mobula kuhlii cf. eregoodootenkee (110.4-120.4 cm disc width; W ), in their embryos (7.0-42.3 cm W ) and also yolks and histrotroph, to assess the potential implications for juvenile nutrition and habitat use. Irrespective of their development in the uterus, embryos had similar δ C values in their muscle tissue as the mothers and both had greater values than in the histotroph. During gestation, δ C values increased across all sample types. However, while embryo muscle tissue and the histotroph were associated with increasing N levels during embryonic development, this was depleted in the mothers' muscle tissue and yolk. Although speculative, the observed variation in stable-isotope ratios might imply a dietary shift among gravid females during their early gestation. Irrespective of the underlying mechanisms, the results indicate neonates will have relatively greater δ N values than post-partum females, which would probably confound juvenile foraging-ecology estimates.