Pub Date : 2023-07-18DOI: 10.1017/S0025315423000413
José Raúl Morales-Ávila, Sarah H. Al-Jufaili, Nicolás Álvarez-Pliego, Ricardo J. Saldierna-Martínez
Abstract This is the first simultaneous morphological and barcoding characterization with the cytochrome c oxidase subunit I (COI) of the bramble shark Echinorhinus from the coast of Oman. The morphology of the specimen was consistent with previous records of Echinorhinus from the Gulf of Oman and the Arabian Sea (Northwestern Indian Ocean). However, the new COI haplotype clustered together with homologous sequences of specimens from India. The specimen from Oman distinguished morphologically and genetically from an E. brucus from the Western Atlantic Ocean on the shape and size of the dermal denticles, the proportions of twelve morphometric measurements (differences ⩾3%) and the genetic p-distance = 3.8% of the COI fragment. The haplotype reported here increases the genetic diversity in genus Echinorhinus in the Northwest Indian Ocean, demonstrates conspecificity between specimens from Oman and Echinorhinus cf. E. brucus distributed in India and extends its range of distribution. The limited morphological and molecular data available constrained assigning our specimen to other than Echinorhinus cf. E. brucus (Bonnaterrez, 1788). Our findings highlight the urgent need of morphological review, redescription and the assignment of a neotype in order to guarantee accurate species identification and thus effective conservation measures for these deep-sea sharks. The existence of a third living species in the genus is briefly discussed.
摘要:本文首次对阿曼海岸的棘猴进行了细胞色素c氧化酶亚基I (COI)的形态学和条形码同时鉴定。该标本的形态与先前在阿曼湾和阿拉伯海(西北印度洋)发现的棘龙的记录一致。然而,新的COI单倍型与印度标本的同源序列聚集在一起。来自阿曼的标本在形态学和遗传学上与来自西大西洋的布鲁氏杆菌在真皮小齿的形状和大小、12个形态测量的比例(差异大于或等于3%)和COI片段的遗传p-距离= 3.8%上进行了区分。本文报道的单倍型增加了西北印度洋棘猴属的遗传多样性,证明了阿曼棘猴与印度棘猴之间的同源性,并扩大了其分布范围。现有的有限形态学和分子数据限制了将我们的标本分配给棘猴cf. E. brucus以外的物种(Bonnaterrez, 1788)。我们的研究结果表明,迫切需要形态学审查,重新描述和新类型的分配,以确保准确的物种鉴定,从而有效地保护这些深海鲨鱼。本文简要讨论了该属中第三种现存物种的存在。
{"title":"Encountering the morphological and molecular complexity in the bramble shark Echinorhinus cf. E. brucus (Bonnaterre 1788) from the Oman Sea","authors":"José Raúl Morales-Ávila, Sarah H. Al-Jufaili, Nicolás Álvarez-Pliego, Ricardo J. Saldierna-Martínez","doi":"10.1017/S0025315423000413","DOIUrl":"https://doi.org/10.1017/S0025315423000413","url":null,"abstract":"Abstract This is the first simultaneous morphological and barcoding characterization with the cytochrome c oxidase subunit I (COI) of the bramble shark Echinorhinus from the coast of Oman. The morphology of the specimen was consistent with previous records of Echinorhinus from the Gulf of Oman and the Arabian Sea (Northwestern Indian Ocean). However, the new COI haplotype clustered together with homologous sequences of specimens from India. The specimen from Oman distinguished morphologically and genetically from an E. brucus from the Western Atlantic Ocean on the shape and size of the dermal denticles, the proportions of twelve morphometric measurements (differences ⩾3%) and the genetic p-distance = 3.8% of the COI fragment. The haplotype reported here increases the genetic diversity in genus Echinorhinus in the Northwest Indian Ocean, demonstrates conspecificity between specimens from Oman and Echinorhinus cf. E. brucus distributed in India and extends its range of distribution. The limited morphological and molecular data available constrained assigning our specimen to other than Echinorhinus cf. E. brucus (Bonnaterrez, 1788). Our findings highlight the urgent need of morphological review, redescription and the assignment of a neotype in order to guarantee accurate species identification and thus effective conservation measures for these deep-sea sharks. The existence of a third living species in the genus is briefly discussed.","PeriodicalId":17477,"journal":{"name":"Journal of the Marine Biological Association of the United Kingdom","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41404932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-18DOI: 10.1017/S0025315423000371
Redha Sidi Ali, G. Khames, Z. Alioua, Rabea Seridji
Abstract The objective of this study was to assess the distribution patterns of dinoflagellates and ciliates communities during planktonic bloom and post-bloom development periods, in relation to environmental parameters. Their distribution was studied during spring and summer 2012, in coastal waters of Algeria at six sampling stations (four sampling layers). Overall, 116 species were identified, including 98 dinoflagellates. The species richness of microzooplankton was higher in summer (81 species: 67 dinoflagellates, seven tintinnids and seven ciliates) than in spring (76 species: 72 dinoflagellates, three naked ciliates and one tintinnid). Significant difference in total abundances was observed between spring (median = 145 ind l−1) and summer (median = 90 ind l−1) but no significance (P > 0.05, Mann–Whitney test) in Shannon–Wiener (H′spring: 3.31 bits ind−1; H′summer: 3.70 bits ind−1) and evenness (Espring: 0.77; Esummer: 0.84) indices. The ciliate average abundance was higher in summer (11.3 ind l−1) than in spring (1.95 ind l−1), whereas dinoflagellate average abundance was lower in summer (127.92 ind l−1) than spring (190.19 ind l−1). Non-metric multidimensional scaling was used to identify different sample assemblages. It showed that temperature and salinity influenced the distribution pattern in the canonical correspondence analysis followed by chlorophyll a, silicate and nitrate concentrations. Our framework provides insight regarding trait trade off with implications for feedbacks to ecosystems, aiming to bridge the gap of plankton community ecology in Algeria. It elaborates a taxonomic list of dinoflagellates and ciliates in the marine pelagic ecosystem and performs their ecological characterization in their environment.
摘要本研究的目的是评估甲藻和纤毛虫群落在浮游水华和水华后发育期的分布模式与环境参数的关系。2012年春季和夏季,在阿尔及利亚沿海水域的六个采样站(四个采样层)研究了它们的分布。总共鉴定了116种,其中包括98种甲藻。夏季微型浮游动物的物种丰富度(81种:67种甲藻、7种丁虫和7种纤毛虫)高于春季(76种:72种甲藻,3种裸纤毛虫和1种丁虫)。春季(中位数=145 ind l−1)和夏季(中位数=90 ind l–1)的总丰度存在显著差异,但在Shannon–Wiener(H′春季:3.31位ind−1;H′夏季:3.70位ind–1)和均匀度(Espring:0.77;Essummer:0.84)指数中没有显著差异(P>0.05,Mann–Whitney检验)。夏季纤毛虫的平均丰度(11.3 ind l−1)高于春季(1.95 ind l–1),而甲藻的平均丰度在夏季(127.92 ind l-1)低于春季(190.19 ind l-1)。使用非度量多维标度来识别不同的样本组合。在典型对应分析中,温度和盐度影响分布模式,其次是叶绿素a、硅酸盐和硝酸盐浓度。我们的框架提供了关于特征权衡的见解,并对生态系统的反馈产生了影响,旨在弥合阿尔及利亚浮游生物群落生态学的差距。阐述了海洋浮游生态系统中甲藻和纤毛虫的分类清单,并对其环境进行了生态表征。
{"title":"Influence of environmental factors on biodiversity, abundance and the distribution pattern of dinoflagellates and ciliates during spring and summer in coastal waters of Algeria (southwestern Mediterranean Sea)","authors":"Redha Sidi Ali, G. Khames, Z. Alioua, Rabea Seridji","doi":"10.1017/S0025315423000371","DOIUrl":"https://doi.org/10.1017/S0025315423000371","url":null,"abstract":"Abstract The objective of this study was to assess the distribution patterns of dinoflagellates and ciliates communities during planktonic bloom and post-bloom development periods, in relation to environmental parameters. Their distribution was studied during spring and summer 2012, in coastal waters of Algeria at six sampling stations (four sampling layers). Overall, 116 species were identified, including 98 dinoflagellates. The species richness of microzooplankton was higher in summer (81 species: 67 dinoflagellates, seven tintinnids and seven ciliates) than in spring (76 species: 72 dinoflagellates, three naked ciliates and one tintinnid). Significant difference in total abundances was observed between spring (median = 145 ind l−1) and summer (median = 90 ind l−1) but no significance (P > 0.05, Mann–Whitney test) in Shannon–Wiener (H′spring: 3.31 bits ind−1; H′summer: 3.70 bits ind−1) and evenness (Espring: 0.77; Esummer: 0.84) indices. The ciliate average abundance was higher in summer (11.3 ind l−1) than in spring (1.95 ind l−1), whereas dinoflagellate average abundance was lower in summer (127.92 ind l−1) than spring (190.19 ind l−1). Non-metric multidimensional scaling was used to identify different sample assemblages. It showed that temperature and salinity influenced the distribution pattern in the canonical correspondence analysis followed by chlorophyll a, silicate and nitrate concentrations. Our framework provides insight regarding trait trade off with implications for feedbacks to ecosystems, aiming to bridge the gap of plankton community ecology in Algeria. It elaborates a taxonomic list of dinoflagellates and ciliates in the marine pelagic ecosystem and performs their ecological characterization in their environment.","PeriodicalId":17477,"journal":{"name":"Journal of the Marine Biological Association of the United Kingdom","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49057270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-18DOI: 10.1017/S0025315423000395
Mengdi Chu, Ying Hao, Yong Huang
Abstract Two new free-living marine nematode species of genus Tripyloides were discovered in intertidal sediments along Rudong coast of the Yellow Sea and on Qi′ao Island of the South China Sea, respectively. They are described here as Tripyloides conicus sp. nov. and Tripyloides boucheri sp. nov. T. conicus sp. nov. is characterized by outer labial setae two-segments, amphideal fovea circular, buccal cavity with four chambers and with a distinct tooth at the bottom, spicules slender and straight, gubernaculum kidney-like with two lateral denticles at distal end, tail sexual dimorphism (elongated conical in males, conico-cylindrical in females). T. boucheri sp. nov. is characterized by body size small, outer labial setae stout, two-segments, amphidial fovea small, circular, narrow conical buccal cavity without distinct tooth, male with papilliform precloacal supplements, spicules slender, gubernaculum with two lateral denticles at distal end, tail conico-cylindrical and not swollen terminally. An updated dichotomous key for fifteen species of the genus is also given.
{"title":"Two new species of genus Tripyloides (Nematoda, Enoplida, Tripyloididae) from the Chinese sea area","authors":"Mengdi Chu, Ying Hao, Yong Huang","doi":"10.1017/S0025315423000395","DOIUrl":"https://doi.org/10.1017/S0025315423000395","url":null,"abstract":"Abstract Two new free-living marine nematode species of genus Tripyloides were discovered in intertidal sediments along Rudong coast of the Yellow Sea and on Qi′ao Island of the South China Sea, respectively. They are described here as Tripyloides conicus sp. nov. and Tripyloides boucheri sp. nov. T. conicus sp. nov. is characterized by outer labial setae two-segments, amphideal fovea circular, buccal cavity with four chambers and with a distinct tooth at the bottom, spicules slender and straight, gubernaculum kidney-like with two lateral denticles at distal end, tail sexual dimorphism (elongated conical in males, conico-cylindrical in females). T. boucheri sp. nov. is characterized by body size small, outer labial setae stout, two-segments, amphidial fovea small, circular, narrow conical buccal cavity without distinct tooth, male with papilliform precloacal supplements, spicules slender, gubernaculum with two lateral denticles at distal end, tail conico-cylindrical and not swollen terminally. An updated dichotomous key for fifteen species of the genus is also given.","PeriodicalId":17477,"journal":{"name":"Journal of the Marine Biological Association of the United Kingdom","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45294911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-18DOI: 10.1017/S0025315423000437
E. Díaz-Cabrera, C. Vega‐Retter, Noemi Roja‐Hernández, E. Meerhoff, B. Dewitte, D. Véliz
Abstract Population connectivity has a fundamental role in metapopulation dynamics with important implications for population persistence in space and time. Oceanic islands, such as Easter Island (EI) and the Salas & Gómez Island (SG), are ideal for the study of population connectivity because they are separated by 415 km and isolated from other islands in the Pacific Ocean by >2000 km. Considering that the dispersal process could play a critical role in the persistence of their populations, we evaluated the connectivity pattern of the endemic gastropod Monetaria caputdraconis between EI and SG using population genetics and biophysical modelling. Eleven microsatellite loci did not show differences in the allelic frequency of individuals located in EI and SG, suggesting the presence of one genetic population. Historical reciprocal migration implies that 0.49% of the recruits in EI come from SG and 0.37% in SG come from EI. Considering year-round larval release and a larval development of 2 weeks in the plankton, a Lagrangian experiment based on a regional oceanic simulation indicated a weak population connectivity with a high rate of self-recruitment. Interestingly, self-recruitment showed both monthly and interannual variation ranging from 1 to 45% of returned larvae, with lower values estimated in SG compared to EI. The results suggest that few larvae/individuals arrive at each other's island, possibly due to stochastic events, such as rafting. Overall, our results indicate that both islands maintain population connectivity despite their distance; these findings have implications for designing conservation strategies in this region.
{"title":"Integrating genetic and biophysical approaches to estimate connectivity in an isolated, insular system: case of the culturally important marine gastropod Monetaria caputdraconis","authors":"E. Díaz-Cabrera, C. Vega‐Retter, Noemi Roja‐Hernández, E. Meerhoff, B. Dewitte, D. Véliz","doi":"10.1017/S0025315423000437","DOIUrl":"https://doi.org/10.1017/S0025315423000437","url":null,"abstract":"Abstract Population connectivity has a fundamental role in metapopulation dynamics with important implications for population persistence in space and time. Oceanic islands, such as Easter Island (EI) and the Salas & Gómez Island (SG), are ideal for the study of population connectivity because they are separated by 415 km and isolated from other islands in the Pacific Ocean by >2000 km. Considering that the dispersal process could play a critical role in the persistence of their populations, we evaluated the connectivity pattern of the endemic gastropod Monetaria caputdraconis between EI and SG using population genetics and biophysical modelling. Eleven microsatellite loci did not show differences in the allelic frequency of individuals located in EI and SG, suggesting the presence of one genetic population. Historical reciprocal migration implies that 0.49% of the recruits in EI come from SG and 0.37% in SG come from EI. Considering year-round larval release and a larval development of 2 weeks in the plankton, a Lagrangian experiment based on a regional oceanic simulation indicated a weak population connectivity with a high rate of self-recruitment. Interestingly, self-recruitment showed both monthly and interannual variation ranging from 1 to 45% of returned larvae, with lower values estimated in SG compared to EI. The results suggest that few larvae/individuals arrive at each other's island, possibly due to stochastic events, such as rafting. Overall, our results indicate that both islands maintain population connectivity despite their distance; these findings have implications for designing conservation strategies in this region.","PeriodicalId":17477,"journal":{"name":"Journal of the Marine Biological Association of the United Kingdom","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44003118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-17DOI: 10.1017/S0025315423000334
X. G. Vital, L. A. Palomino-Alvarez, D. Ortigosa, E. Guerra-Castro, Nuno Simões
Abstract Cryptic species in coral reefs, such as sea slugs, represent an important portion of their biodiversity, which is usually underestimated. Autonomous Reef Monitoring Structures (ARMS) have been implemented to estimate cryptic diversity in coral reefs. Therefore, this research aimed to contribute to the southern Gulf of Mexico (GM) and the Caribbean Sea (CAR) coral reefs’ sea slugs’ diversity and distribution using ARMS as a collection method. Fifty-eight ARMS were placed at three coral reefs in the GM and CAR, recovered after 1–2 years and then, disassembled at the laboratory. Plates were individually placed in trays with seawater, where we searched for sea slugs. A total of 242 organisms were found belonging to 31 species; 20 of them were identified to the species level, while 11 were determined up to genus or family. More than half of the species (19) were found in Bajo de 10 (GM), while 15 species were found in the CAR localities. Unlike previous studies, we assessed sea slugs’ diversity exclusively by an indirect sampling method. In this work, we found 9.4% of the sea slug diversity recorded in the Caribbean, and we report four determined species for the first time in the country. New records of species, and even one family for the GM stress the gap of information that we still need to fulfil in the area. We recognize ARMS as a useful tool to find juvenile, cryptic and rare species of sea slugs, as well as to standardize their quantification and record their diversity.
摘要珊瑚礁中的隐蔽物种,如海蛞蝓,是其生物多样性的重要组成部分,通常被低估。已经实施了自主珊瑚礁监测结构(ARMS)来估计珊瑚礁的隐蔽多样性。因此,本研究旨在利用ARMS作为一种收集方法,为墨西哥湾南部(GM)和加勒比海(CAR)珊瑚礁海蛞蝓的多样性和分布做出贡献。58个ARMS被放置在GM和CAR的三个珊瑚礁上,在1-2年后回收,然后在实验室拆解。盘子被单独放置在装有海水的托盘中,我们在那里寻找海蛞蝓。共发现242种生物,分属31个物种;其中20个被鉴定到物种水平,11个被确定到属或科。超过一半的物种(19种)是在Bajo de 10(GM)发现的,而15种是在CAR地区发现的。与之前的研究不同,我们完全通过间接采样方法评估海蛞蝓的多样性。在这项工作中,我们发现了加勒比海记录的9.4%的海蛞蝓多样性,并首次在该国报告了四个已确定的物种。新的物种记录,甚至是转基因的一个家族,都强调了我们在该地区仍然需要完成的信息缺口。我们认识到ARMS是一种有用的工具,可以发现幼年、隐蔽和稀有的海蛞蝓物种,并对其数量进行标准化和记录其多样性。
{"title":"Sea slugs (Gastropoda: Heterobranchia) associated with Autonomous Reef Monitoring Structures (ARMS) in southern Gulf of Mexico and Mexican Caribbean Sea","authors":"X. G. Vital, L. A. Palomino-Alvarez, D. Ortigosa, E. Guerra-Castro, Nuno Simões","doi":"10.1017/S0025315423000334","DOIUrl":"https://doi.org/10.1017/S0025315423000334","url":null,"abstract":"Abstract Cryptic species in coral reefs, such as sea slugs, represent an important portion of their biodiversity, which is usually underestimated. Autonomous Reef Monitoring Structures (ARMS) have been implemented to estimate cryptic diversity in coral reefs. Therefore, this research aimed to contribute to the southern Gulf of Mexico (GM) and the Caribbean Sea (CAR) coral reefs’ sea slugs’ diversity and distribution using ARMS as a collection method. Fifty-eight ARMS were placed at three coral reefs in the GM and CAR, recovered after 1–2 years and then, disassembled at the laboratory. Plates were individually placed in trays with seawater, where we searched for sea slugs. A total of 242 organisms were found belonging to 31 species; 20 of them were identified to the species level, while 11 were determined up to genus or family. More than half of the species (19) were found in Bajo de 10 (GM), while 15 species were found in the CAR localities. Unlike previous studies, we assessed sea slugs’ diversity exclusively by an indirect sampling method. In this work, we found 9.4% of the sea slug diversity recorded in the Caribbean, and we report four determined species for the first time in the country. New records of species, and even one family for the GM stress the gap of information that we still need to fulfil in the area. We recognize ARMS as a useful tool to find juvenile, cryptic and rare species of sea slugs, as well as to standardize their quantification and record their diversity.","PeriodicalId":17477,"journal":{"name":"Journal of the Marine Biological Association of the United Kingdom","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49370370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-10DOI: 10.1017/S0025315423000383
H. Serrano, Cecília J. S. Damiano, R. Alitto, P. D. Guilherme, W. R. P. Cerqueira, J. B. Mendonça, M. Tavares, Michela Borges
Abstract The brittle stars of the family Ophiocomidae inhabit shallow waters and coral reefs of tropical regions. The species of Ophiocoma are difficult to identify due to high morphological variation, especially when different stages of development are observed. Here, based on morphological analyses, two Brazilian morphotypes of Ophiocoma were studied and characterized, Ophiocoma sp. NB (Northeastern Brazil) and Ophiocoma sp. TMV (Trindade and Martin Vaz Archipelago), and subsequently thoroughly analysed to confirm whether they were the same species or not. After the morphological studies, including external morphology, morphometry and microstructural characters, and analysis of molecular data, involving the 16S gene, it was concluded that Ophiocoma sp. NB and Ophiocoma sp. TMV do not correspond to the same species, the first being identified as Ophiocoma echinata (Lamarck, 1816) and the latter being a new species. This new species is characterized by two tentacle scales on the first arm segment and then one on all following segments, and the dorsalmost arm spines are robust and rounded, as wide as long or almost as wide as long.
{"title":"A new species of Ophiocoma (Echinodermata: Ophiuroidea) from Archipelago Trindade and Martin Vaz, Southeastern Atlantic, and redescription of Ophiocoma echinata","authors":"H. Serrano, Cecília J. S. Damiano, R. Alitto, P. D. Guilherme, W. R. P. Cerqueira, J. B. Mendonça, M. Tavares, Michela Borges","doi":"10.1017/S0025315423000383","DOIUrl":"https://doi.org/10.1017/S0025315423000383","url":null,"abstract":"Abstract The brittle stars of the family Ophiocomidae inhabit shallow waters and coral reefs of tropical regions. The species of Ophiocoma are difficult to identify due to high morphological variation, especially when different stages of development are observed. Here, based on morphological analyses, two Brazilian morphotypes of Ophiocoma were studied and characterized, Ophiocoma sp. NB (Northeastern Brazil) and Ophiocoma sp. TMV (Trindade and Martin Vaz Archipelago), and subsequently thoroughly analysed to confirm whether they were the same species or not. After the morphological studies, including external morphology, morphometry and microstructural characters, and analysis of molecular data, involving the 16S gene, it was concluded that Ophiocoma sp. NB and Ophiocoma sp. TMV do not correspond to the same species, the first being identified as Ophiocoma echinata (Lamarck, 1816) and the latter being a new species. This new species is characterized by two tentacle scales on the first arm segment and then one on all following segments, and the dorsalmost arm spines are robust and rounded, as wide as long or almost as wide as long.","PeriodicalId":17477,"journal":{"name":"Journal of the Marine Biological Association of the United Kingdom","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45354965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-10DOI: 10.1017/S002531542300036X
C. Sassa, Motomitsu Takahashi, Y. Tsukamoto
Abstract Diaphus fulgens is a diel vertical migrant myctophid, occurring abundantly in the Kuroshio waters of the East China Sea. They are multiple batch spawners with a short interspawn period, resulting in high egg productivity. Multiple spawning would be supported by feeding during their spawning season; however, there is no information on the feeding habits of this species. The present study examined the diet composition, diel feeding periodicity and daily ration of mature adult D. fulgens collected at different periods of the day during February to March. The most prevalent item was appendicularians and their mucus houses, which dominated the stomach contents in both number and weight. Additionally, various species of copepods were predated, with a prevalence, by weight, of the large-sized Pleuromamma piseki. Diaphus fulgens feeds actively in the epipelagic layer at night and moves down to the mesopelagic layer in the early morning, and digests most of the consumed food by the late afternoon, showing a typical nocturnal feeding pattern. Based on diel changes in the stomach content index and instantaneous gastric evacuation rate estimated in this study (0.118–0.129 h−1), the daily ration was calculated to be 4.0–4.2% of body weight, equivalent to a daily caloric intake of 21.2–22.3 cal day−1. Since the caloric value to produce a batch of oocytes was estimated to be 8.2–11.5 cal day−1, on an energetic basis, D. fulgens can maintain the multiple spawning at a cost of approximately 37–54% of its daily caloric intake.
摘要:黄颡鱼是东海黑潮水域中大量存在的一种垂直洄游嗜鱼。它们是多批产卵者,产卵间隔时间短,产卵率高。在产卵季节通过进食来支持多次产卵;然而,没有关于这个物种的食性的信息。研究了2 ~ 3月不同时段采集的黄颡鱼成虫的日粮组成、日采食周期和日定量。最常见的是阑尾虫和它们的粘液屋,它们在数量和重量上都占主导地位。此外,许多种类的桡足类动物在此之前就已经存在,以重量计,大型胸鳍鱼(Pleuromamma piseki)普遍存在。黄横鱼夜间在上层捕食活跃,清晨下移至中层,傍晚消化掉大部分进食的食物,呈现典型的夜间捕食模式。根据胃内容物指数的变化和本研究估计的瞬时胃排空率(0.118-0.129 h - 1),计算出日摄食量为体重的4.0-4.2%,相当于每日摄入21.2-22.3 cal day - 1。由于产生一批卵母细胞的热量值估计为8.2-11.5 cal day−1,因此在能量基础上,富尔根D.可以维持多次产卵,其成本约为其每日热量摄入的37-54%。
{"title":"Diet composition, diel feeding periodicity and daily ration of mature adult Diaphus fulgens (Teleostei: Myctophidae) in the Kuroshio waters","authors":"C. Sassa, Motomitsu Takahashi, Y. Tsukamoto","doi":"10.1017/S002531542300036X","DOIUrl":"https://doi.org/10.1017/S002531542300036X","url":null,"abstract":"Abstract Diaphus fulgens is a diel vertical migrant myctophid, occurring abundantly in the Kuroshio waters of the East China Sea. They are multiple batch spawners with a short interspawn period, resulting in high egg productivity. Multiple spawning would be supported by feeding during their spawning season; however, there is no information on the feeding habits of this species. The present study examined the diet composition, diel feeding periodicity and daily ration of mature adult D. fulgens collected at different periods of the day during February to March. The most prevalent item was appendicularians and their mucus houses, which dominated the stomach contents in both number and weight. Additionally, various species of copepods were predated, with a prevalence, by weight, of the large-sized Pleuromamma piseki. Diaphus fulgens feeds actively in the epipelagic layer at night and moves down to the mesopelagic layer in the early morning, and digests most of the consumed food by the late afternoon, showing a typical nocturnal feeding pattern. Based on diel changes in the stomach content index and instantaneous gastric evacuation rate estimated in this study (0.118–0.129 h−1), the daily ration was calculated to be 4.0–4.2% of body weight, equivalent to a daily caloric intake of 21.2–22.3 cal day−1. Since the caloric value to produce a batch of oocytes was estimated to be 8.2–11.5 cal day−1, on an energetic basis, D. fulgens can maintain the multiple spawning at a cost of approximately 37–54% of its daily caloric intake.","PeriodicalId":17477,"journal":{"name":"Journal of the Marine Biological Association of the United Kingdom","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42964248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-10DOI: 10.1017/S0025315423000401
F. A. Puente-Tapia, D. Ortigosa, X. G. Vital, L. A. Palomino-Alvarez
Abstract Ctenophores are one of the least known invertebrate phyla in Mexico, especially the benthic forms in which studies are incomplete and infrequent, lacking information about their ecology and diversity. As part of the environmental monitoring project ‘Biodiversidad Marina de Yucatán’ conducted in the southern Gulf of Mexico and Mexican Caribbean Sea, the benthic ctenophore Vallicula multiformis (Coeloplanidae) was identified in association with green algae in the southern Gulf of Mexico, and on an autonomous reef monitoring structure in the Mexican Caribbean Sea. This finding represents the first record of the occurrence of a benthic ctenophore species in Mexican waters. We provide morphological characteristics of V. multiformis in both reef areas. Recording this species increases the known number of Mexican ctenophore fauna from 33 to 34 taxa and represents baseline information for the continuous study of the ecology and diversity of benthic ctenophores in Mexico.
{"title":"First record of a benthic ctenophore in the Mexican Atlantic: Vallicula multiformis (Platyctenida, Coeloplanidae)","authors":"F. A. Puente-Tapia, D. Ortigosa, X. G. Vital, L. A. Palomino-Alvarez","doi":"10.1017/S0025315423000401","DOIUrl":"https://doi.org/10.1017/S0025315423000401","url":null,"abstract":"Abstract Ctenophores are one of the least known invertebrate phyla in Mexico, especially the benthic forms in which studies are incomplete and infrequent, lacking information about their ecology and diversity. As part of the environmental monitoring project ‘Biodiversidad Marina de Yucatán’ conducted in the southern Gulf of Mexico and Mexican Caribbean Sea, the benthic ctenophore Vallicula multiformis (Coeloplanidae) was identified in association with green algae in the southern Gulf of Mexico, and on an autonomous reef monitoring structure in the Mexican Caribbean Sea. This finding represents the first record of the occurrence of a benthic ctenophore species in Mexican waters. We provide morphological characteristics of V. multiformis in both reef areas. Recording this species increases the known number of Mexican ctenophore fauna from 33 to 34 taxa and represents baseline information for the continuous study of the ecology and diversity of benthic ctenophores in Mexico.","PeriodicalId":17477,"journal":{"name":"Journal of the Marine Biological Association of the United Kingdom","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48969384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-06DOI: 10.1017/S0025315423000358
L. Sampognaro, M. C. López-Abbate, D. Calliari
Abstract The microzooplankton community structure (species abundance, biomass, diversity) was investigated at a coastal marine station on the South-West Atlantic Ocean (34°23′S–53°45′W, Uruguay). This is a hydrographically complex site within the Subtropical Convergence zone of the SW Atlantic where knowledge of the microzooplankton is particularly scant. The main goal was to perform a first characterization of that community and evaluate its association to environmental drivers along an annual cycle. Oceanographic variables (temperature, salinity, irradiance, nutrients, chlorophyll-a) and ciliates (aloricate and loricate), and dinoflagellates were recorded monthly from July 2019 to June 2020. Over 100 microzooplankton taxa belonging to approximately 30 families and 40 genera were identified, including several subtropical and subantarctic species. Community structure followed wide transitions at the seasonal scale – particularly between summer and winter as subtropical taxa alternated with euryhaline taxa from colder subantarctic waters. The core environmental variables (temperature, salinity and dissolved inorganic nitrogen [DIN]) explained overall variance in microzooplankton community assembly. During summer, high temperatures (20.3, 16.3–22.4°C) and low nutrients (DIN: 3.5, 0.7–6.7 μM; PO4: 1.0, 0.8–1.5 μM) benefited the development of aloricate ciliates. A nutrient pulse in winter posed favourable stoichiometric conditions and the numerical abundance was dominated by dinoflagellates and loricate ciliates in the following months, while diversity remained highest (taxonomic richness: 36 [22–46]; Shannon–Wiener index: 2.5 [1.9–2.8]). Results suggested that the microzooplankton community at the study site is mainly structured by hydrographic variability linked to the seasonal replacement of offshore water masses that differed in thermohaline properties and nutrient levels, and local processes.
{"title":"Microzooplankton community structure in a subtropical South-West Atlantic coastal site","authors":"L. Sampognaro, M. C. López-Abbate, D. Calliari","doi":"10.1017/S0025315423000358","DOIUrl":"https://doi.org/10.1017/S0025315423000358","url":null,"abstract":"Abstract The microzooplankton community structure (species abundance, biomass, diversity) was investigated at a coastal marine station on the South-West Atlantic Ocean (34°23′S–53°45′W, Uruguay). This is a hydrographically complex site within the Subtropical Convergence zone of the SW Atlantic where knowledge of the microzooplankton is particularly scant. The main goal was to perform a first characterization of that community and evaluate its association to environmental drivers along an annual cycle. Oceanographic variables (temperature, salinity, irradiance, nutrients, chlorophyll-a) and ciliates (aloricate and loricate), and dinoflagellates were recorded monthly from July 2019 to June 2020. Over 100 microzooplankton taxa belonging to approximately 30 families and 40 genera were identified, including several subtropical and subantarctic species. Community structure followed wide transitions at the seasonal scale – particularly between summer and winter as subtropical taxa alternated with euryhaline taxa from colder subantarctic waters. The core environmental variables (temperature, salinity and dissolved inorganic nitrogen [DIN]) explained overall variance in microzooplankton community assembly. During summer, high temperatures (20.3, 16.3–22.4°C) and low nutrients (DIN: 3.5, 0.7–6.7 μM; PO4: 1.0, 0.8–1.5 μM) benefited the development of aloricate ciliates. A nutrient pulse in winter posed favourable stoichiometric conditions and the numerical abundance was dominated by dinoflagellates and loricate ciliates in the following months, while diversity remained highest (taxonomic richness: 36 [22–46]; Shannon–Wiener index: 2.5 [1.9–2.8]). Results suggested that the microzooplankton community at the study site is mainly structured by hydrographic variability linked to the seasonal replacement of offshore water masses that differed in thermohaline properties and nutrient levels, and local processes.","PeriodicalId":17477,"journal":{"name":"Journal of the Marine Biological Association of the United Kingdom","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"57067866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-04DOI: 10.1017/S0025315423000346
Y. H. Dinh, N. Lam, F. Lishchenko
Abstract Lutjanus malabaricus represents a widely distributed and intensively exploited snapper species. The present article is the first attempt to describe the life-history traits of L. malabaricus in Vietnamese waters and estimate their variability. The fish were collected at the landing sites of Nghe An and Ha Tinh provinces from June 2020 to May 2021. The standard length of fish ranged from 10 to 74 cm, weight varied between 18.53 and 8972.89 g, age ranged from 1 to 17 years and all three parameters were subjected to a significant seasonal variation. A similar seasonal pattern was observed in the variation of maturity and gonadosomatic index. We assume that the observed variation of the stock structure is the result of spawning migrations when large fish migrate inshore from the foraging grounds. Growth and weight gain of fish were described via the von Bertalanffy function, constants of the equations were as follows: L∞ = 76.2, K = −0.077, t0 = −2.26 in males and L∞ = 56.9, K = −0.176, t0 = −0.48 in females; W∞ = 6498, K = −0.100, t0 = −1.96 in males and W∞ = 8317, K = −0.100, t0 = −1.31 in females. The growth constants of the North Vietnamese stock of L. malabaricus are similar to the ones of the North-eastern Australian stock. A general tendency for the reduction of the growth rate and asymptotic size from equatorial waters to higher latitudes was observed.
{"title":"Life-history traits variation of Lutjanus malabaricus (Bloch & Schneider, 1801) in the waters off Northern Vietnam","authors":"Y. H. Dinh, N. Lam, F. Lishchenko","doi":"10.1017/S0025315423000346","DOIUrl":"https://doi.org/10.1017/S0025315423000346","url":null,"abstract":"Abstract Lutjanus malabaricus represents a widely distributed and intensively exploited snapper species. The present article is the first attempt to describe the life-history traits of L. malabaricus in Vietnamese waters and estimate their variability. The fish were collected at the landing sites of Nghe An and Ha Tinh provinces from June 2020 to May 2021. The standard length of fish ranged from 10 to 74 cm, weight varied between 18.53 and 8972.89 g, age ranged from 1 to 17 years and all three parameters were subjected to a significant seasonal variation. A similar seasonal pattern was observed in the variation of maturity and gonadosomatic index. We assume that the observed variation of the stock structure is the result of spawning migrations when large fish migrate inshore from the foraging grounds. Growth and weight gain of fish were described via the von Bertalanffy function, constants of the equations were as follows: L∞ = 76.2, K = −0.077, t0 = −2.26 in males and L∞ = 56.9, K = −0.176, t0 = −0.48 in females; W∞ = 6498, K = −0.100, t0 = −1.96 in males and W∞ = 8317, K = −0.100, t0 = −1.31 in females. The growth constants of the North Vietnamese stock of L. malabaricus are similar to the ones of the North-eastern Australian stock. A general tendency for the reduction of the growth rate and asymptotic size from equatorial waters to higher latitudes was observed.","PeriodicalId":17477,"journal":{"name":"Journal of the Marine Biological Association of the United Kingdom","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42485556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}