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2. Spatial and Temporal Distribution of Benthic Dinoflagellates on Artificial Substrate at Seribu Islands Waters.

Author

Widiarti, Riani, Ilyas, Ahmad Jutrzenka, Triputra, Kresnanda, Kusuma, Muhammad Praja, Rachman, Arief, and Tan Toh Hii

Abstract

Damage to coral reef ecosystems and changes in water quality are capable of increasing the abundance of benthic dinoflagellates which could cause Ciguatera Fish Poisoning (CFP). Therefore, this research aimed to observe spatial and temporal abundance of those potential benthic dinoflagellates and analyze their relationship with environmental factors. Sampling was carried out on September 21-24, 2023 in Pramuka Island, Seribu Islands district, with different treatments, namely depth, location and time. Research conducted by deploy several series of artificial substrates into the waters, and the benthic dinoflagellates were collected from the artificial substrate placed in 1, 3, and 5 meter of water depths for 24, 48, and 72 hours at Odi, Mazu, and Villa Delima Piers. Cell densities were determined by enumeration using a Sedgewick Rafter Counting Chamber under a light microscope, and the relationship with environmental parameters was analyzed by using Principal Component Analysis (PCA). The results showed that 4 genera of benthic dinoflagellates which had the potential to cause CFP, were attached to the artificial substrate, namely Amphidinium, Coolia, Ostreopsis, and Prorocentrum. Prorocentrum cells were observed in highest number on artificial substrates at every treatment with different depths, locations, and times. Furthermore, the PCA analysis showed the abundance of Prorocentrum was influenced by the most typical environmental parameters at each depth, location, and time, namely temperature, nitrate, DO, and light intensity. The research provided valuable information on the benthic dinoflagellates both spatially and temporally, through international standard methods in order to prevent and anticipate negative impacts caused by CFP. [ABSTRACT FROM AUTHOR]

Published
2024
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7. 1st Postgraduate Seminar on Agriculture and Forestry 2021

Author

Abu Bakar, Fauziah, Tan, Toh Hii, Ramaiya, Shiamala Devi, Asmuni, Mohd Ikmal, Kwan, Yee Min, Universiti Putra Malaysia Bintulu Sarawak Campus, Faculty of Agricultural Science and Forestry, Abu Bakar, Fauziah, Tan, Toh Hii, Ramaiya, Shiamala Devi, Asmuni, Mohd Ikmal, Kwan, Yee Min, and Universiti Putra Malaysia Bintulu Sarawak Campus, Faculty of Agricultural Science and Forestry

Published
2021

8. Attributing Ceratocorys, Pentaplacodinium and Protoceratium to Protoceratiaceae (Dinophyceae), with descriptions of Ceratocorys malayensis sp. nov . and Pentaplacodinium usupianum sp. nov

Author

Luo, Zhaohe, Lim, Zhen Fei, Mertens, Kenneth, Krock, Bernd, Teng, Sing Tung, Tan, Toh Hii, Leaw, Chui Pin, Lim, Po Teen, Gu, Haifeng, Luo, Zhaohe, Lim, Zhen Fei, Mertens, Kenneth, Krock, Bernd, Teng, Sing Tung, Tan, Toh Hii, Leaw, Chui Pin, Lim, Po Teen, and Gu, Haifeng

Abstract

The gonyaulacean family Protoceratiaceae is characterised by five precingular plates. It currently encompasses the type genus Ceratocorys and the fossil genus Atopodinium. Fourteen strains of Ceratocorys, Pentaplacodinium, and Protoceratium were established from Malaysian and Hawaiian waters, and their morphologies were examined using light and scanning electron microscopy. Two new species, Ceratocorys malayensis sp. nov. and Pentaplacodinium usupianum sp. nov., were described from Malaysian waters. They share a Kofoidean plate formula of Po, Pt, 3ʹ, 1a, 6ʹʹ, 6C, 6S, 5ʹʹʹ, 1p, 1ʹʹʹʹ. Ceratocorys malayensis has a short first apical plate (1ʹ) with no direct contact with the anterior sulcal plate (Sa) whereas Pentaplacodinium usupianum had a parallelogram-shaped 1ʹ plate which often contacted the Sa plate. The genera Ceratocorys and Pentaplacodinium were emended accordingly to incorporate species bearing five or six precingular plates. The Protoceratium strain from Hawaii was morphologically similar to P. reticulatum, but differed in the lack of a ventral pore in plate 1′ and slight or lack of contact between plates 1′ and Sa, and is here designated as P. cf. reticulatum. The maximum-likelihood and Bayesian inference analyses based on SSU, LSU and ITS ribosomal DNA sequences revealed that these three genera are monophyletic and form a well-resolved group. Our results support Protoceratium and Pentaplacodinium as members of the family Protoceratiaceae, characterised by the presence of one anterior intercalary plate. Seven strains of Protoceratium cf. reticulatum, Ceratocorys malayensis and Pentaplacodinium usupianum were examined for yessotoxin production by LC-MS/MS but none produced a detectable amount of toxin.

Published
2020
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10. Attributing Ceratocorys, Pentaplacodiniumand Protoceratiumto Protoceratiaceae (Dinophyceae), with descriptions of Ceratocorys malayensis sp. nov. and Pentaplacodinium usupianum sp. nov.

Author

Luo, Zhaohe, Lim, Zhen Fei, Mertens, Kenneth Neil, Krock, Bernd, Teng, Sing Tung, Tan, Toh Hii, Leaw, Chui Pin, Lim, Po Teen, and Gu, Haifeng

Abstract

ABSTRACTThe gonyaulacean family Protoceratiaceae is characterised by five precingular plates. It currently encompasses the type genus Ceratocorysand the fossil genus Atopodinium. Fourteen strains of Ceratocorys, Pentaplacodinium, and Protoceratiumwere established from Malaysian and Hawaiian waters, and their morphologies were examined using light and scanning electron microscopy. Two new species, Ceratocorys malayensis sp. nov. and Pentaplacodinium usupianum sp. nov., were described from Malaysian waters. They share a Kofoidean plate formula of Po, Pt, 3ʹ, 1a, 6ʹʹ, 6C, 6S, 5ʹʹʹ, 1p, 1ʹʹʹʹ. Ceratocorys malayensishas a short first apical plate (1ʹ) with no direct contact with the anterior sulcal plate (Sa) whereas Pentaplacodinium usupianumhad a parallelogram-shaped 1ʹ plate which often contacted the Sa plate. The genera Ceratocorysand Pentaplacodiniumwere emended accordingly to incorporate species bearing five or six precingular plates. The Protoceratiumstrain from Hawaii was morphologically similar to P. reticulatum, but differed in the lack of a ventral pore in plate 1′ and slight or lack of contact between plates 1′ and Sa, and is here designated as P. cf. reticulatum. The maximum-likelihood and Bayesian inference analyses based on SSU, LSU and ITS ribosomal DNA sequences revealed that these three genera are monophyletic and form a well-resolved group. Our results support Protoceratiumand Pentaplacodiniumas members of the family Protoceratiaceae, characterised by the presence of one anterior intercalary plate. Seven strains of Protoceratiumcf. reticulatum, Ceratocorys malayensisand Pentaplacodinium usupianumwere examined for yessotoxin production by LC-MS/MS but none produced a detectable amount of toxin.

Published
2020
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