An updated inventory of sea slugs from Koh Tao, Thailand, with notes on their ecology and a dramatic biodiversity increase for Thai waters

Improved access to field survey infrastructure throughout South-East Asia has allowed for a greater intensity of biodiversity surveys than ever before. The rocky bottoms and coral reef habitats across the region have been shown to support some of the highest sea slug biodiversity on the planet, with ever increasing records. During the past ten years, intensive SCUBA surveys have been carried out at Koh Tao, in the Gulf of Thailand, which have yielded remarkable findings in sea slug biology and ecology. In this work a brief history of sea slug biodiversity research from Thailand is covered and a complete inventory of sea slugs from Koh Tao, Gulf of Thailand is provided. This inventory is based on surveys from 2012 to 2020, with previously unreported findings since 2016. Habitat specificity and species-specific ecology are reported where available with a focused comparison of coral reef habitats and deeper soft-sediment habitats. The findings contribute 90 new species records for Thai waters (92 for the Gulf of Thailand) and report a remarkable consistency in the proportional diversity found to be exclusive to one habitat type or another. Additionally, taxonomic remarks are provided for species documented from Koh Tao that have not been discussed in past literature from Thailand, and a summary of previous records in the Indo-West Pacific is given.

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A new subspecies of Finlayson’s squirrel from an isolated island offshore of the Indochina Peninsula in southern Vietnam

Mammalia ◽

10.1515/mammalia-2021-0015 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Duong Thuy Vu ◽

Son Truong Nguyen ◽

Masaharu Motokawa ◽

Tu Ngoc Ly ◽

Phuong Huy Dang ◽

...

Keyword(s):

Gulf Of Thailand ◽

Small Islands ◽

Mitochondrial Cytochrome ◽

Indochina Peninsula ◽

New Subspecies ◽

Southern Vietnam ◽

History Of ◽

The Gulf Of Thailand ◽

The Last Glacial Maximum ◽

The Last Glacial

Abstract We describe a new subspecies of Finlayson’s squirrel (Callosciurus finlaysonii) from Hon Nghe Island in the Gulf of Thailand. This island is located off the coast of southern Vietnam. In addition, we discussed the phylogenetic relationships among C. finlaysonii subspecies distributed on the isolated islands in the Gulf of Thailand. The new subspecies (C. finlaysonii honnghensis), which is endemic to Hon Nghe Island, differs from other C. finlaysonii subspecies in pelage colouration. The mitochondrial cytochrome b sequences showed that this squirrel is closely related to C. finlaysonii albivexilli and C. finlaysonii frandseni, which are endemic to the Koh Kut and Koh Chang islands, respectively, suggesting that the three subspecies diverged approximately 30,000 years ago. After the last glacial maximum, many small islands were formed by the sea level rise in the Gulf of Thailand, which was a consequence of global warming. Following the continuous fragmentation of the Sunda Continent, each C. finlaysonii subspecies could have evolved in each geographically isolated island in this gulf. Thus, studying C. finlaysonii subspecies may be used to track the recent geological history of the Gulf of Thailand.

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History of Thai maritime trade

Maritime Technology and Research ◽

10.33175/mtr.2019.147777 ◽

2018 ◽

Vol 1 (1) ◽

pp. Proof

Author(s):

Somchart Krailassuwan

Keyword(s):

World War I ◽

Andaman Sea ◽

Maritime Trade ◽

Gulf Of Thailand ◽

Company Limited ◽

Maritime Shipping ◽

History Of ◽

The Gulf Of Thailand ◽

The Government ◽

Set Up

The Thai commercial fleet can carry about 10% of the volume of imports and exports. History of Thai maritime trade is divided into 1) Sukhothai period era 2) Ayutthaya and Thonburi period 3) Rattanakosin period 4) The first of the national fleet period. .Sukhothai period era trade with various foreign countries. In the King Ramkhamhaeng era is a prosperous.. 1) The Gulf of Thailand trade with China 2) Trade on the Andaman sea is a merchant ship from India. Ayutthaya and Thonburi period. Traders of various nationalities come to trade. The Gulf of Thailand (South China Sea) and the Indian Ocean. Trading in Ayutthaya is a monopoly trade, operated by monarchs and noblemen.Rattanakosin period Thailand entered into a Treaty of Burney, the outcome of the agreement was that the country had to cancel its monopoly trade and the end of trade by the government. The growth of the trade has increased. The production structure from the old to be self-transformed into production for export. The first of the national fleet period 1918 - 1925 After the First World War I King Rama VI established a Thai merchant fleet in April 1918, the name of Siam Commercial Maritime Company Limited. It was terminated in 1925. On June 22, 1940, the cabinet approved the establishment of Thai Maritime Navigation Company Limited for international maritime shipping. The The cabinet was terminated in 2011 .The role of Thai National Maritime Navigation.The merchant fleet were not growing. Because lack of and thai merchant fleet too small, there was a lack of negotiating power with the foreign merchant fleet. The government must set up a policy to promote the merchant fleet.

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Potential release of PCBs from plastic scientific gear to fringing coral reef sediments in the Gulf of Thailand

Deep Sea Research Part II Topical Studies in Oceanography ◽

10.1016/j.dsr2.2013.02.012 ◽

2013 ◽

Vol 96 ◽

pp. 41-49 ◽

Cited By ~ 3

Author(s):

Gi Hoon Hong ◽

Chang Joon Kim ◽

Thamasak Yeemin ◽

Fernando P. Siringan ◽

Jing Zhang ◽

...

Keyword(s):

Coral Reef ◽

Gulf Of Thailand ◽

The Gulf Of Thailand

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Case History of One Trip Monobore Completion System - Two Years of Cement-Through Monobore Completions in the Gulf of Thailand

10.2118/103668-ms ◽

2006 ◽

Cited By ~ 1

Author(s):

Walter Ray Chapman

Keyword(s):

Case History ◽

Gulf Of Thailand ◽

History Of ◽

The Gulf Of Thailand

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Sedimentary History of Trace Metals Over the Past Half-Century in Songkhla Lake, Western Coast of the Gulf of Thailand: Anthropogenic Impacts and Contamination Assessment

Frontiers in Earth Science ◽

10.3389/feart.2021.767899 ◽

2021 ◽

Vol 9 ◽

Author(s):

Ke Dong ◽

Shuqing Qiao ◽

Bin Wu ◽

Xuefa Shi ◽

Yufei Chen ◽

...

Keyword(s):

Magnetic Susceptibility ◽

Trace Metals ◽

Organic Carbon ◽

Relative Reduction ◽

Western Coast ◽

Organic Carbon Content ◽

Gulf Of Thailand ◽

History Of ◽

The Gulf Of Thailand ◽

Songkhla Lake

Coastal lagoons are among the most vulnerable and economically significant ecosystems on Earth. Songkhla Lake, connected with the Gulf of Thailand, is the second largest lake in Southeast Asia and supports the development of the fishery, transportation, and tourism industries in southern Thailand. With increasing anthropogenic disturbances, the lake is facing acute ecological problems and further research is needed. Here, we provide 55-year record of grain size, color reflectance, magnetic susceptibility, total organic carbon, total nitrogen, and trace element (As, Hg, Pb, Cr, Ni, Cu, and Zn) concentrations of sediment core SKL8-2 collected from Songkhla Lake. These records reveal a three-stage sedimentary and input history of trace metals under anthropogenic effects: 1) From 1964 to 1982, it was a natural terrigenous input period with a relative reduction environment when the channel connecting Songkhla Lake and the Gulf of Thailand was closed. 2) Trace metal concentrations, organic carbon content, b* value, and magnetic susceptibility changed abruptly in 1982. During 1982–2000, the sources of trace metals were more complex than during 1964–1982 and mainly came from urban wastewater, industrial effluent, and fishery discharge. 3) From 2000 to 2019, contamination signals of Pb, Hg, As, Zn, and Ni emerged in the first decade because of the rapid development and poor sewage treatment around nearby cities.

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On the Plakobranchidae (Gastropoda, Sacoglossa) from soft sediment habitats of Koh Tao, Gulf of Thailand, with descriptions of two new species

ZooKeys ◽

10.3897/zookeys.969.52941 ◽

2020 ◽

Vol 969 ◽

pp. 85-121

Author(s):

Rahul Mehrotra ◽

Manuel Caballer Gutierrez ◽

Chad M. Scott ◽

Spencer Arnold ◽

Coline Monchanin ◽

...

Keyword(s):

Morphological Variability ◽

South East Asia ◽

Gulf Of Thailand ◽

Soft Sediment ◽

Species Problem ◽

Sea Slug ◽

Species Complexes ◽

Sea Slugs ◽

The Family ◽

The World

Research in recent years have provided rapid advances in biogeographic and taxonomic documentation of sea slugs around the world. However, efforts are lacking in surveying most coastlines and habitats in South-East Asia. Recent studies from the Gulf of Thailand have indicated that a wealth of unexplored sea slug diversity and ecology may be gained from an investigation of soft sediment habitats beyond the reef slopes. Additionally, the waters of Koh Tao have been found to host regionally high levels of sea slug diversity with several species awaiting taxonomic clarification. In this work the initial findings of an expanded survey effort from the waters around Koh Tao are provided, with the identity of two soft sediment-associated sacoglossan species in the family Plakobranchidae being investigated. By integrating morphological and molecular analyses, the species Plakobranchus noctisstellatussp. nov. and Elysia aowthaisp. nov. are described and species complexes surrounding Plakobranchus ocellatus van Hasselt, 1824 and Elysia japonica Eliot, 1913 are discussed. The topics of morphological variability and the cryptic species problem are also discussed.

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