Monograph |
Corresponding author: Kantapon Suraprasit ( kantapon.s@chula.ac.th ) Academic editor: Fedor Konstantinov
© 2024 Parin Jirapatrasilp, Gilles Cuny, László Kocsis, Chirasak Sutcharit, Nom Ngamnisai, Thasinee Charoentitirat, Satapat Kumpitak, Kantapon Suraprasit.
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Citation:
Jirapatrasilp P, Cuny G, Kocsis L, Sutcharit C, Ngamnisai N, Charoentitirat T, Kumpitak S, Suraprasit K (2024) Mid-Holocene marine faunas from the Bangkok Clay deposits in Nakhon Nayok, the Central Plain of Thailand. ZooKeys 1202: 193-208. https://doi.org/10.3897/zookeys.1202.119389
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Based on several field investigations, many molluscan shells and chondrichthyan teeth, together with other invertebrate and actinopterygian remains were found from the marine Bangkok Clay deposits in Ongkharak, Nakhon Nayok, at a depth of ~ 5–7 m below the topsoil surface. Animal macrofossils recovered from these Holocene marine deposits were identified and their chronological context was investigated in order to reconstruct the paleoenvironments of the area at that time. The majority of marine fossils recovered from the site consist of molluscs, with a total of 63 species identified. Other invertebrate species include a stony coral, a mud lobster, barnacles, and a sea urchin. The vertebrates are represented by fish remains, including carcharhinid shark teeth from at least nine species, stingray and trichiurid teeth, and one sciaenid otolith. The molluscan fauna indicates that the paleoenvironments of the area corresponded to intertidal to sublittoral zones, where some areas were mangrove forests and intertidal mudflats. The fish fauna is dominated by the river shark Glyphis, indicating freshwater influences and possibly occasional brackish conditions. The carbon-14 analysis of mollusc and charcoal remains shows that deposition of the marine sediment sequence began during the mid-Holocene, spanning approximately from 8,800 to 5,300 cal yr BP. This study provides in-depth insights into the diversity of fishes, marine molluscs, and other invertebrates from the Bangkok Clay deposits, supporting the existence of a marine transgression onto the Lower Central Plain of Thailand during the mid-Holocene.
carbon-14 dating, Chao Phraya River Basin, Chondrichthyes, marine transgression, mollusc, paleoenvironment
The Holocene began approximately 11,700 years ago and belongs to one of the interglacial periods. Prior to the Holocene, during the period of the Last Glacial Maximum (LGM), the global climate was much colder and dryer and was a period of significant landscape changes in many areas due to a lowered sea level, approximately 120 m below the present-day stands (
The Central Plain of Thailand is an important area where the topography and climate changes were under the influence of a sea level rise starting at ~ 12 ka. The region covers the plains between the mountain ranges along the lower northern part of Thailand, including the Yom and Nan River basins, and the low-lying plains of the Chao Phraya, Tha Chin, Mae Klong and Bang Pakong River basins near the Gulf of Thailand (
The extent of marine intrusion into the Central Plain of Thailand during the Holocene was largely interpreted based on various studies (e.g., geomorphological, sedimentological, paleontological, palynological, and stratigraphical data as well as carbon-14 dating of peat layers). These studies indicated that the ancient coastal shoreline of the Gulf of Thailand was located further north in Phra Nakhon Si Ayutthaya Province during 7.3–6.5 ka (
In addition to the inference of ancient coastal shorelines during the Holocene, studies on faunas and floras along the ancient coast of the Gulf of Thailand are crucial to understand paleoenvironmental and palaeoecological changes in response to climatic oscillations. The ancient coastal habitats occupied by these animals are investigated based on the identification and dating of fossils (e.g., molluscs, arthropods, and vertebrates). According to accurate species-level identification, microhabitats can be investigated based on comparisons between fossils and living species or related taxa. The paleoenvironments of the area are also reconstructed based on the identification of various groups of animals because each of them has a different mode of life in a specific habitat (
Marine faunas from the Holocene Bangkok Clay deposits of the Central Plain of Thailand have infrequently been analysed in detail, and we identify the animal macrofossils recovered from the clay pit of Ongkharak, Nakhon Nayok Province in central Thailand (Fig.
The study area is located at the clay pit in Ban Lad Chang, Chumpon Subdistrict, Ongkharak District, Nakhon Nayok Province (13°59'30.9"N, 100°55'11.5"E) in the Lower Central Plain of Thailand (Fig.
The rectangular mine is 1,000 m long × 400 m wide and 30 m deep. It was opened to produce clay material used in construction sites. The active mining operations of the clay pit allow us to have access to the stratigraphic sequence of the Quaternary deposits of the area (Fig.
The study area and the sediment profile of the clay pit A the clay pit of Ongkharak, Nakhon Nayok Province in central Thailand B the Bangkok clay layer bearing numerous in situ complete shells of Placuna placenta C Shells of a bivalve Anadara inaequivalvis buried in situ in the Bangkok clay deposits D lithological profile of the clay pit E the contact between two successive layers: coarse-grained sand (upper) and black clay (lower) F the contact between three successive layers: black clay (upper), lateritic soil (middle), and yellowish brown clay to silt (lower) G the contact between two successive layers: purplish (upper) and greyish (lower) clay to sand H the contact between two successive layers: greyish clay to sand (upper) and reddish brown lateritic layer (lower).
The Bangkok clay layer at the clay pit of Ongkharak has yielded nearly in situ fossil deposits as indicated by preservation of complete shells with both valves attached (Fig.
Species identification of specimens is mainly based on the existing literature specified under the treatment of each taxon. The specimens are kept at the Department of Geology, Faculty of Science, Chulalongkorn University, and coded as the name of the collection (CUF: Chulalongkorn fossil collection), followed by the locality (NKNY: Nakhon Nayok) and the catalogue number. Fish remains including teeth and otolith as well as some small shells were photographed with a scanning electron microscope (SEM; JEOL, JSM-5410 LV) or a Leica M205C stereo light microscope with fusion optics and the Leica Application Suite Image System. L and R designate left and right valves of bivalve shells, respectively.
We selected six samples (shells and charcoal) collected from the marine clay deposits at different depths in the clay pit for carbon-14 dating (Table
AMS 14C ages of shells and charcoal collected from the clay pit of Ongkharak in Nakhon Nayok, central Thailand.
Lab Code | Sample type | Depths (m) below the uppermost part of a marine clay layer | 14C age (yr BP) | Calibrated 14C (2-sigma) age (cal yr BP) |
---|---|---|---|---|
D-AMS 044190 | Shell (Tellinides conspicuus) | 2.2 | 5303 ± 26 | 5882–5464 |
D-AMS 044191 | Shell (Pholas orientalis) | 2.2 | 5202 ± 28 | 5757–5318 |
D-AMS 044193 | Charcoal | 2.2 | 5047 ± 26 | 5899–5726 |
D-AMS 044195 | Charcoal | 3.4 | 6186 ± 29 | 7166–6983 |
D-AMS 044194 | Shell (Magallana cf. gigas) | 4 | 7241 ± 32 | 7901–7510 |
D-AMS 044192 | Charcoal | 4.6 | 7913 ± 26 | 8784–8600 |
The ages of the Bangkok Clay deposits in the clay pit of Ongkharak range from 8,784 calibrated years before the present (cal yr BP) to 5,318 cal yr BP (mid-Holocene) based on the radiocarbon dating of several shell and charcoal fragments collected along the stratigraphic section of the layer (Table
The vertebrate remains include at least nine species (two families) of chondrichthyan fishes and at least two species (two families) of actinopterygian taxa. Altogether, 100 cartilaginous fish fossils were recovered, including 97 remains identified as belonging to the family Carcharhinidae and three to the family Dasyatidae. The teeth of the latter belong to the stingray genus Pastinachus. Among the carcharhinids, the genus Glyphis dominates the shark fauna (61%). There are also at least six species of Carcharhinus, representing 26% of the shark fauna. The accurate identification of Carcharhinus species is often hindered by the preservation of teeth or by the morphological similarities of tooth positions among these taxa. A few teeth among the carcharhinids belong to the genus Scoliodon. Few actinopterygian remains were also found, including three teeth that belong to the family Trichiuridae and one sciaenid otolith that represents the genus Johnius.
Class Anthozoa Ehrenberg, 1834
Subclass Hexacorallia Haeckel, 1896
Order Scleractinia Bourne, 1900
Oulangia Milne Edwards & Haime, 1848
cf.Oulangia stokesiana Milne Edwards & Haime, 1848: pl. 7, fig. 4, 4a. Type locality: Philippines.
cf.Oulangia stokesiana stokesiana.
CUF-NKNY-O07 (1 specimen; Figs
Size comparison of coral and gastropods found in this study A Oulangia cf. stokesiana B Neripteron violaceum C Nerita articulata D Natica stellata E Natica vitellus F Homalopoma cf. sangarense G Eunaticina papilla H Ergaea walshi I Pirenella incisa J Scalptia scalariformis K Telescopium telescopium L Merica elegans M Cerithidea obtusa N Bufonaria rana O Nassarius micans P Nassarius siquijorensis Q Paratectonatica tigrina.
Shallow waters as well as in submarine caves (
Indian Ocean; Indo-West Pacific, from Japan to the Philippines, and central Pacific (
This specimen is classified into the genus Oulangia based on the descriptions and figures of
Class Gastropoda Cuvier, 1795
Subclass Vetigastropoda Salvini-Plawen, 1980
Order Trochida Cox & Knight, 1960
Superfamily Trochoidea Rafinesque, 1815
Homalopoma Carpenter, 1864
cf.Turbo sangarensis Schrenck, 1861: 409–410. Type locality: the Sangaric strait near the shore of the island of Jesso [Sangar (Tsugaru) Strait, Hakodate Bay, Hokkaido, Japan].
cf.Homalopoma sangarense.
CUF-NKNY-G24 (1 shell; Figs
On silty-sandy or rarely on rocky substrates at a depth from 2 to 22 m (
Sea of Japan and southern Kuril Islands (
This is the first record of this species in Thailand.
Although there is only one incomplete specimen, it is tentatively identified as H. sangarense based on shell size and shape and several strong spiral cords on the surface as in the descriptions and figures in
Order Cycloneritida Frýda, 1998
Superfamily Neritoidea Rafinesque, 1815
Family Neritidae Rafinesque, 1815
Neripteron Lesson, 1831
Nerita violacea Gmelin, 1791: 3686. Type locality: unknown.
Neritina violacea.
Dostia violacea.
Neripteron violacea.
Neritina (Dostia) violacea.
Neritina (Neripteron) violacea.
Neripteron violaceus.
Neripteron violaceum.
CUF-NKNY-G26 (28 shells; Figs
On Nipa palms, muddy surfaces, old wood and rocks in brackish habitats and mangrove forests (
India (
Gulf of Thailand and Andaman Sea (
The shell of N. violaceum is highly similar to that of N. cornucopia (Benson, 1836) but differs in having a purple to orangish red ventral side, and denticulations along the columellar edge often only present in the central part (
Nerita lineata
Gmelin, 1791: 3684 [junior homonym of Nerita lineata Müller, 1774]. Type locality: Strait of Malacca.
Nerita (Ritena) lineata.
Nerita articulata
Gould, 1847: 220. Type locality: Tavoy.
Nerita balteata
Reeve, 1855: pl. 6, fig. 28. Type locality: unknown.
Nerita (Ritena) balteata.
Nerita (Amphinerita) articulata.
Nerita (Nerita) articulata.
Nerita (Theliostyla) balteata.
Nerita balteata forma articulata.
Nerita (Cymostyla) balteata.
CUF-NKNY-G61 (3 shells; Figs
On tree trunks, branches, roots and on muddy banks and rocky areas or near mangrove forests (
India (
Gulf of Thailand and Andaman Sea (
This species is recognised by numerous raised spiral cords and a crenulated outer lip (
Cohort Sorbeoconcha Ponder & Lindberg, 1997
Subcohort Cerithiimorpha Golikov & Starobogatov, 1975
Superfamily Cerithioidea Fleming, 1822
Cerithidea Swainson, 1840
Cerithium obtusum Lamarck, 1822: 71. Type locality: Timor.
Cerithidea obtusa.
Cerithidea (Cerithidea) obtusa.
CUF-NKNY-G14 (23 shells; Figs
On firm mud and on trunks and stilt roots in mangrove forests as well as in fully marine and estuarine areas (
Bay of Bengal; Indo-West Pacific, from southern Vietnam to Java and East Borneo (
Chanthaburi River, Gulf of Thailand and Andaman Sea (
This species has a more thickened and flared aperture compared to two similar species, Cerithidea anticipata Iredale, 1929 and C. reidi Houbrick, 1986. These two species are also common in Sahul (New Guinea and Australia), whereas C. obtusa is present in Sunda (
Cerithium incisum Hombron & Jacquinot, 1848: 97, pl. 23, figs 8, 9. Type locality: Borneo.
Cerithidea (Cerithideopsilla) djadjariensis
[non Martin].
Cerithideopsilla djadjariensis
[non Martin].
Pirenella incisa.
CUF-NKNY-G10 (47 shells; Figs
On damp mud in mangrove forests. Also found on open surface areas of intertidal mudflats and on muddy shores of shrimp ponds (
East India; Indo-West Pacific, from southern China, the Philippines to West Sulawesi, and Flores Island (
Gulf of Thailand and Andaman Sea (
This species differs from the other two similar species, Pirenella pupiformis Ozawa & Reid, 2016 and P. caiyingyai (Qian, Fang & He, 2013), by the presence of an almost columnar appearance, a more oblique and more flared aperture with the projection of a lip next to a deep anterior canal, and three equal cords on each spire whorl with strong square nodules on axial ribs (
Trochus telescopium Linnaeus, 1758: 760. Type locality: unknown.
Telescopium telescopium.
CUF-NKNY-G64 (2 shells; Figs
On muddy floors of mangrove forests and intertidal mud flats (
Indian Ocean; Indo-West Pacific, from Japan to India (
Gulf of Thailand and Andaman Sea (
This species is recognised by its high conical spire with a broad, rather flat base, and a twisted columella with a strong and central spiral ridge (
Superfamily Naticoidea Guilding, 1834
Eunaticina Fischer, 1885
Nerita papilla Gmelin, 1791: 3675. Type locality: Tranquebar [Tharangambadi, Tamil Nadu, India].
Eunaticina papilla.
Eunaticina papilla papilla.
CUF-NKNY-G19 (5 shells; Figs
Fine sandy bottoms in intertidal zones down to 30 m depth (
Red Sea to Indian Ocean; Indo-West Pacific, from Japan to Australia and Fiji Islands (
Gulf of Thailand and Andaman Sea (
This species is recognised by a regularly oval shell with a small spire and a large body whorl with low and wide spiral cords, which are broader than their interspaces and crossed by prominent axial ridges (
Natica stellata
Hedley, 1913: 299–300. Type locality: unknown.
Natica (Natica) stellata.
CUF-NKNY-G05 (126 shells; Figs
Sandy gravel bottoms in sublittoral zones down to 20 m depth (
Indo-West Pacific, from Japan to Australia (
Gulf of Thailand and Andaman Sea (
This species differs from its similar species, Natica vitellus, in having a parietal callus forming a tongue-shaped extension over the posterior part of the umbilicus (
Nerita vitellus Linnaeus, 1758: 776. Type locality: Asiatic Ocean.
Natica vitellus.
Natica (Natica) vitellus.
Natica vitellus vitellus.
CUF-NKNY-G04 (5 shells; Figs
Fine sandy or muddy bottoms in intertidal zones down to ~ 120 m depth (
Persian Gulf to Indian Ocean; Indo-West Pacific, from Japan to Australia (
Gulf of Thailand and Andaman Sea (
This species differs from its similar species, Natica stellata, in lacking a tongue-shaped extension of a parietal callus over the posterior part of the umbilicus (
Cochlis tigrina Röding, 1798: 147. Type locality: unknown.
Natica tigrina.
Paratectonatica tigrina.
Tectonatica tigrina.
Notocochlis tigrina.
CUF-NKNY-G03 (70 shells; Figs
Sandy mud in intertidal zones down to 30 m depth (
India (
Gulf of Thailand and Andaman Sea (
This species is recognised by its tall-spired shell with deeply impressed sutures and spiral rows of reddish-brown spots on a white background (
Superfamily Calyptraeoidea Lamarck, 1809
Ergaea H. Adams & A. Adams, 1854
Crepidula walshi
Reeve, 1859: Crepidula, pl. 3, sp. 17. Type locality: Singapore; Ceylon [Sri Lanka].
Ergaea walshi.
Crepidula walshii
[sic].
Siphopatella walshi.
Crepidula (Siphopatella) walshi.
Crepidula (Ergaea) walshi.
CUF-NKNY-G25 (10 shells; Figs
Attached to the aperture of other shelled marine organisms, in intertidal zones down to 40 m depth (
Persian Gulf; Indo-West Pacific, from Japan to the Arafura Sea (
Gulf of Thailand and Andaman Sea (
This species is recognised by an irregularly subrectangular and flattened shell, with a small apex close to the posterior margin, and a shelf-like internal septum attached just inside the posterior margin (
Bufonaria Schumacher, 1817
Murex rana Linnaeus, 1758: 748. Type locality: Asiatic Ocean.
Bursa (Bufonaria) rana.
Bursa rana.
Bufonaria rana.
Bufonaria (Bufonaria) rana.
CUF-NKNY-G06, G07 (18 shells; Figs
Muddy or sandy bottoms at a depth from 20 to 100 m (
Red Sea to Indian Ocean; Indo-West Pacific, from Japan to Australia (
Gulf of Thailand and Andaman Sea (
This species is recognised based on the descriptions and figures in
Superfamily Volutoidea Rafinesque, 1815
Cancellaria elegans
Sowerby I, 1822: Cancellaria, pl. 218, fig. 3. Type locality: unknown.
Cancellaria asperella
[sic].
Merica elegans.
CUF-NKNY-G18 (3 shells; Figs
Sandy and muddy bottoms at a depth from 10 to 30 m (
Indo-West Pacific, from Japan to the Philippines. Records of fossils from the Miocene in Indonesia, and from the Quaternary in Japan (
Gulf of Thailand and Andaman Sea (
This species differs from its similar species, Merica asperella (Lamarck, 1822), in having a slenderer and more fusiform shell with a narrower aperture and a sculptured shell with finer and more numerous ribs crossed by spiral ridges nearly of the same strength, showing a rectangular reticulated pattern (
Cancellaria scalariformis Lamarck, 1822: 115. Type locality: unknown.
Cancellaria (Trigonostoma) scalariformis.
Trigonostoma scalariformis.
Scalptia scalariformis.
Scalptia (Scalptia) scalariformis.
CUF-NKNY-G64 (1 shell; Figs
Sand and muddy bottoms at a depth from 20 to 40 m in sublittoral zones (
Indian Ocean; Indo-West Pacific, from Japan to Australia (
Gulf of Thailand (
This species differs from its similar species, Scalptia bicolor (Hinds, 1843), by having a higher and narrower body whorl and a less widely open umbilicus (
Pseudoneptunea Kobelt, 1882
Neptunea varicosa Röding, 1798: 116. Type locality: unknown.
Siphonalia (Pseudoneptunea) aff. varicosa.
Pseudoneptunea varicosa.
CUF-NKNY-G13, G16, G17 (25 shells; Figs
Size comparison of gastropods found in this study A Brunneifusus ternatanus B Murex trapa C Indothais lacera D Pristiterebra miranda E Chicoreus capucinus F Indothais gradata G Ellobium aurisjudae H Inquisitor vulpionis I Turricula javana J Architectonica perdix K Pseudoneptunea varicosa L Cassidula nucleus M Pseudoetrema fortilirata N Paradrillia melvilli O Duplicaria tricincta P Granuliterebra bathyrhaphe Q Comitas ilariae R Cylichna modesta S Maoritomella vallata.
Shallow water at a depth from 10 to 15 m (
Indo-West Pacific, from Vietnam to Indonesia (
Gulf of Thailand and Andaman Sea (
This species is recognised based on the descriptions and figures in
Brunneifusus Dekkers, 2018
Murex ternatanus Gmelin, 1791: 3554. Type locality: Ternate Island, North Maluku, Indonesia.
Pugilina ternatana.
Hemifusus ternatanus.
Brunneifusus ternatanus.
CUF-NKNY-G21, G22 (71 shells; Figs
Mud and muddy sand bottoms from the low tide mark to ~ 10–50 m depth (
Eastern Indian Ocean; Indo-West Pacific, from Taiwan to Indonesia and the Philippines (
Gulf of Thailand and Andaman Sea (
This species is the sole member of the genus Brunneifusus, characterised by a determinate outer lip, compared to the indeterminate growth of the outer lip in Hemifusus Swainson, 1840 (
Nassarius Duméril, 1805
Nassa micans A. Adams, 1852: 106. Type locality: Cagayan, Misamis, Mindanao.
Nassarius (Zeuxis) micans.
Nassarius micans.
CUF-NKNY-G27 (53 shells; Figs
Sandy bottoms in subtidal zones down to 50 m depth (
Gulf of Oman to India; Indo-West Pacific, from Japan to Papua New Guinea (
Gulf of Thailand (
This species differs from its similar species, Nassarius comptus (A. Adams, 1852), by having a longer body whorl with narrowly subcanaliculate sutures, a more prominent varix, and a narrower and more elongate aperture (
Nassa siquijorensis A. Adams, 1852: 97. Type locality: Island of Siquijor, Philippines.
Nassa (Zeuxis) siquijorensis.
Nassarius (Zeuxis) siquijorensis.
Nassarius siquijorensis.
Zeuxis siquijorensis.
Nassarius siquinjorensis
[sic].
CUF-NKNY-G01 (10 shells; Figs
Sandy and muddy bottoms from subtidal zones to 450 m depth (
Red Sea to India; Indo-West Pacific, from Japan to Indonesia and New Caledonia (
Gulf of Thailand and Andaman Sea (
This species differs from its similar species, Nassarius castus (Gould, 1850), in having a more tapering spire, canaliculate sutures, and considerably more numerous axial ribs (
Chicoreus Montfort, 1810
Murex capucinus Lamarck, 1822: 164. Type locality: unknown.
Naquetia capucina.
Chicoreus (Rhizophorimurex) capucinus.
Chicoreus capucinus.
Chicoreus (Naquetia) capucinus.
Chicoreus copucinus
[sic].
CUF-NKNY-G11, G12 (30 shells; Figs
Muddy sand and rocks in mangrove forests (
Indo-West Pacific, from the Philippines to Australia to Fiji Islands (
Gulf of Thailand and Andaman Sea (
This species is recognised based on the descriptions and figures in
Purpura gradata Jonas, 1846: 14–15. Type locality: Indian Ocean, near Singapore.
Thais gradata.
Stramonita gradata.
Indothais gradata.
CUF-NKNY-G29 (1 shell; Figs
Rocky bottom at a depth from 1 to 5 m (
Indo-West Pacific, from Japan to Australia (
Andaman Sea (
This species is recognised based on the descriptions and figures in
Murex lacerus Born, 1778: 107–108. Type locality: unknown.
Cymia lacera.
Thais lacera.
Cuma lacera.
Indothais lacera.
Mangrove forests (
South Africa to India; Indo-West Pacific, from Japan to New Caledonia (
Gulf of Thailand and Andaman Sea (
This species is recognised based on the descriptions and figures in
Murex trapa
Röding, 1798: 145. Type locality: Tranquebar, India.
Murex cf. trapa.
Murex (Murex) trapa.
CUF-NKNY-G09 (33 shells; Figs
Fine sand and muddy sand bottoms at a depth of 5–60 m (
Indian Ocean; Indo-West Pacific, from Japan to Fiji Islands (
Gulf of Thailand and Andaman Sea (
This species differs from other related species in having a higher spire, angulated whorls, and shorter spines (
Maoritomella Powell, 1942
Drillia vallata
Gould, 1860: 336. Type locality: Hong Kong.
Asthenotoma vallata.
Maoritomella vallata.
Probably present in shallow sublittoral areas (
Indo-West Pacific. Records of fossils from the Holocene in Thailand (
Gulf of Thailand (
This species is recognised based on the descriptions and figures in
Pseudoetrema Oyama, 1953
Drillia fortilirata
Smith, 1879b: 194, pl. 19, fig. 22. Type locality: Station 14, east of Goto Islands, 32°48'N, 129°6'E; 47 fathoms, and station 21, between south-western extremity of Niphon and the island of Shikoku, 33°45'N, 132°30'E, 30 fathoms.
Pseudoetrema fortilirata.
CUF-NKNY-G38 (5 shells; Figs
Sand and sandy mud in sublittoral areas to 50 m depth (
Japan and Thailand. Records of fossils from the Pliocene to Holocene in Japan, Taiwan, and Thailand (
Gulf of Thailand (
This species is recognised based on the descriptions and figures in
Turricula Schumacher, 1817
Murex javanus Linnaeus, 1767: 1221. Type locality: Java.
Turricula (Vulpecula) javana.
Turricula javana.
CUF-NKNY-G15, G20 (53 shells; Figs
Intertidal sand and rocks and muddy bottoms at a depth from 20 to 80 m (
Indian Ocean; Indo-West Pacific, from Japan to Australia (
Gulf of Thailand and Andaman Sea (
This species is recognised based on the descriptions and figures in
Paradrillia Makiyama, 1940
Paradrillia melvilli
Powell, 1969: 314–315, pl. 242, fig. 2; pl. 245, figs 1, 2. Type locality: Persian Gulf.
CUF-NKNY-G52 (7 shells; Figs
Sublittoral and upper bathyal zones (
Persian Gulf and Indian Ocean; Gulf of Thailand. Records of fossils from the Holocene in Thailand (
Gulf of Thailand (
This species is recognised based on the descriptions and figures in
Inquisitor Hedley, 1918
Inquisitor vulpionis
Kuroda & Oyama in
CUF-NKNY-G28 (1 shell; Figs
Sandy bottoms at a depth from 10 to 100 m (
Japan and the Philippines. Records of fossils from the Holocene in Thailand (
Gulf of Thailand (
This species is recognised based on the descriptions and figures in
Comitas ilariae
Bozzetti, 1991: 26–28, figs 1–3. Type locality: island of Bohol, central Philippines.
CUF-NKNY-G55 (1 shell; Figs
Sandy bottoms at a depth from 100 to 150 m (
Known only from the type locality (
New record in Thailand from this study.
This species is recognised based on the descriptions and figures in
Duplicaria Dall, 1908
Terebra tricincta
Smith, 1877: 225. Type locality: Persian Gulf.
Granuliterebra tricincta.
Duplicaria tricincta.
Sandy mud bottoms at a depth from 10 to 50 m (
Persian Gulf; Indo-West Pacific, from Japan to Australia (
Gulf of Thailand and Andaman Sea (
This species is recognised based on the descriptions and figures in
Terebra (Myurella) bathyrhaphe Smith, 1875: 415. Type locality: Gulf of Yedo [Edo Bay, Honshu, Japan].
Terebra
sp.
Terebra bathyrhaphe.
Granuliterebra bathyrhaphe.
CUF-NKNY-G66 (1 shell; Figs
Muddy and sandy bottoms from intertidal zones to 200 m depth (
Persian Gulf and Indian Ocean; Indo-West Pacific, from Japan to Australia (
Gulf of Thailand (
This species is recognised based on the descriptions and figures in
Myurella miranda Smith, 1873: 267–268. Type locality: Malacca.
Terebra miranda.
Pristiterebra miranda.
CUF-NKNY-G23 (17 shells; Figs
At sea depth of 6–10 m (
Indo-West Pacific, from Thailand to Indonesia (
Gulf of Thailand (
This species is recognised based on the descriptions and figures in
Grade “Lower Heterobranchia”
Superfamily Architectonicoidea Gray, 1850
Architectonica Röding, 1798
Solarium perdix Hinds, 1844: 22–23. Type locality: Ceylon; north-west coast of Australia.
Architectonica perdix.
Sandy and muddy bottoms at a depth from 10 to 60 m (
Indian Ocean; Indo-West to Central Pacific, from China to Australia and Polynesia (
Gulf of Thailand and Andaman Sea (
This species differs from its similar species, Adelphotectonica reevei (Hanley, 1862), by having a much smaller protoconch and a much higher upper point of attachment of the whorls (
Subcohort Euopisthobranchia Jörger et al., 2010
Order Cephalaspidea Fischer, 1883
Superfamily Cylichnoidea H. Adams & A. Adams, 1854
Cylichna Lovén, 1846
Cylichna modesta
Thiele, 1925: 241–242 [275–276], pl. 44 [32], fig. 7. Type locality: “Neu-Amsterdam”, Station 167 (37° 47’ südl. Br., 77° 33.7’ östl. L., 496 m).
Adamnestia modesta.
CUF-NKNY-G39 (11 shells; Figs
Sublittoral in muddy or fine sandy bottoms (
Southwest Pacific. Records of fossils from the Holocene in Thailand (
Gulf of Thailand (
This species differs from its similar species, Cylichna sibogae Schepman, 1913, by having a less slender shell and an adapical umbilicus unbounded by sharp angulation (
Superorder Eupulmonata Haszprunar & Huber, 1990
Order Ellobiida Van Mol, 1967
Superfamily Ellobioidea Pfeiffer, 1854
Ellobium Röding, 1798
Bulla aurisjudae Linnaeus, 1758: 728. Type locality: unknown.
Ellobium aurisjudae.
Ellobium (Ellobium) cf. aurisjudae.
Ellobium (Ellobium) aurisjudae.
CUF-NKNY-G65 (25 shells; Figs
In estuaries, mangrove and coastal forests, on salt marshes above the normal high tide line in or under rotting wood, and on sandy soil bordering a sandy beach (
Arabian Gulf and Indian Ocean; Indo-West Pacific, from South China Sea to Australia (
Gulf of Thailand and Andaman Sea (
This species is recognised based on the descriptions and figures in
Helix nucleus Gmelin, 1791: 3193. Type locality: “Tahiti” [Cooktown, Queensland, Australia].
Auricula mustelina Deshayes, 1830: 92. Type locality: “New Zealand”.
Cassidula nucleus.
Cassidula mustelina.
CUF-NKNY-G63 (1 shell; Figs
On mud in shaded areas and on tree trunks in mangrove and nipa palm forests, sometimes present in salt marsh or on muddy tidal flats (
Arabian Gulf and Indian Ocean; Indo-West Pacific, from Japan to Australia (
Gulf of Thailand and Andaman Sea (
This species differs from its similar species, Cassidula aurisfelis (Bruguière, 1789), by having a normal and non-bifurcated columellar fold, a less rounded outline with a less convex shoulder, a straighter aperture, and a thinner palatal ridge (
Subclass Protobranchia Pelseneer, 1889
Order Nuculanida Carter et al., 2000
Superfamily Nuculanoidea H. Adams & A. Adams, 1858
Jupiteria Bellardi, 1875
Nucula puellata Hinds, 1843: 100. Type locality: Malacca; from 10 to 17 fathoms, coarse sand.
Nuculana puellata.
Nuculana (Jupiteria) puellata.
Jupiteria puellata.
CUF-NKNY-B25 (37 shells; Figs
Size comparison of bivalves, scaphopod and other invertebrates found in this study A Tegillarca nodifera B Volachlamys singaporina C Tegillarca granosa D Noetiella pectunculiformis E Magallana cf. gigas F Estellacar olivacea G Anadara indica H Dentalium variabile I Siliqua minima J Corbula fortisulcata K Fistulobalanus kondakovi L Placamen lamellatum M Martesia striata N Potamocorbula sp. O Jupiteria puellata P Saccella mauritiana Q Paratapes undulatus R Dosinia dilecta S Joannisiella oblonga T Temnotrema siamense U Pholas orientalis.
Subtidal on coarse sand, soft clay, and mud bottoms at a depth from 5 to 40 m (
Indo-West Pacific, from southern China to New Guinea (
Gulf of Thailand (
This species is recognised based on the descriptions and figures in
Nucula mauritiana Sowerby I, 1833: 15, fig. 7. Type locality: Mauritius.
Nuculana mauritiana.
Nuculana (Scaeoleda) caspidata
[non Gould].
Nuculana (Scaeoleda) mauritiana.
Sacella mauritiana
[sic].
Nuculana (Saccella) mauritiana.
Saccella mauritiana.
CUF-NKNY-B24 (20 shells; Figs
Sublittoral on mainly mud and clay with sand and shells at a depth from 11 to 92 m (
Indian Ocean; Indo-West Pacific, from China to Indonesia (
Gulf of Thailand and Andaman Sea (
This species is recognised based on the descriptions and figures in
Arca inaequivalvis
Bruguière, 1789: 106–107. Type locality: East India.
Scapharca inaequivalvis.
Anadara (Scapharca) inaequivalvis.
Anadara cf. inaequivalvis.
Anadara inaequivalvis.
CUF-NKNY-B03, B21 (21L+30R shells; Figs
Size comparison of bivalves and other invertebrates found in this study A Placuna placenta B Standella pellucida C Geloina bengalensis D Anadara inaequivalvis E Pegophysema bialata F Megabalanus cf. tintinnabulum G Cultellus maximus H Lutraria complanata I Thalassina sp. J Tellinides conspicuus.
Sandy and muddy bottoms in intertidal and upper sublittoral zones (
Red Sea to India Ocean; Indo-West Pacific, from Japan to Australia as well as from Mediterranean and Black Sea (
Gulf of Thailand and Andaman Sea (
This species is recognised based on the descriptions and figures in
Arca indica
Gmelin, 1791: 3312. Type locality: the Indian Ocean.
Anadara (Scapharca) indica.
Scapharca indica.
Anadara indica.
Anadara (Anadara) indica.
CUF-NKNY-B06 (16L+24R shells; Figs
In soft sand or sandy mud bottoms at bays, river mouths, and intertidal zones down to 15 m depth (
Persian Gulf to India Ocean; Indo-West Pacific, from Japan to Australia (
Gulf of Thailand and Andaman Sea (
This species is recognised based on the descriptions and figures in
Arca granosa
Linnaeus, 1758: 694. Type locality: southern European ocean.
Arca (Anadara) granosa.
Anadara granosa.
Anadara (Tegillarca) granosa.
Tegillarca granosa.
CUF-NKNY-B20 (15L+15R shells; Figs
Mud down to 10 m depth in mangrove forests and muddy estuaries (
East Africa to India; Indo-West Pacific, from Japan to Australia and Polynesia (
Gulf of Thailand and Andaman Sea (
This species differs from its similar species, Tegillarca nodifera, by having a less elongated shell with a lower number of ribs (15–21) and a lower number of nodules on ribs (
Arca nodifera Martens, 1860: 17. Type locality: Bankok [Bangkok, Thailand].
Anadara nodifera.
Anadara (Tegillarca) nodifera.
Tegillarca nodifera.
On mud and sand bottoms, in intertidal or near mangrove forests and shallow sublittoral waters down to a depth of 10 m (
Eastern Indian Ocean; Indo-West Pacific, from East China Sea to Indonesia (
Gulf of Thailand and Andaman Sea (
This species differs from its similar species, Tegillarca granosa, by having a more elongated shell with a higher number of ribs (19–23) and a higher number of nodules on ribs (
Estellacar Iredale, 1939
Arca olivacea Reeve, 1844: Arca, pl. 16, sp. 113. Type locality: San Nicolas, island of Zebu [the Philippines] (found in sandy mud at the depth of four fathoms).
Estellacar olivacea.
Striarca olivacea.
CUF-NKNY-B18 (16L+14R shells; Figs
In mud and sand from intertidal zones, often near mangrove forests, down to 20 m depth (
India; Indo-West Pacific, from South China to the Philippines (
Gulf of Thailand and Andaman Sea (
This species differs from its similar species Estellacar galactodes (Benson, 1842) by having a higher number of coarser riblets (
Barbatia pectunculiformis Dunker, 1866: 88–89, pl. 28, figs 4–6. Type locality: Borneo.
Arca (Fossularca) pectunculiformis.
Striarca pectunculiformis.
Scelidionarca pectunculiformis.
Noetiella pectunculiformis.
CUF-NKNY-B27 (4L+4R shells; Figs
In soft clay, mud or sand, in subtidal zones from a depth of 2–43 m, and in mangrove forests (
India Ocean; Indo-West Pacific, from South China to Indonesia (
Gulf of Thailand and Andaman Sea (
This species is recognised based on the descriptions and figures in
Magallana Salvi & Mariottini, 2016
cf.Ostrea gigas Thunberg, 1793: 140–142, pl. 6, figs 1–3. Type locality: Japan.
cf.Crassostrea gigas.
cf.Crassostrea cf. gigas.
cf.Crassostrea (Magallana) gigas.
cf.Magallana gigas.
CUF-NKNY-B13 (130L+16R shells; Figs
Attached to rocks from intertidal zones down to 30 m depth, in mud, bays, and sheltered areas that are often brackish with low salinity water (
Cosmopolitan (
Gulf of Thailand and Andaman Sea (
The cupped oysters in the subfamily Crassostreinae could not be identified at species level based on shell characters or soft tissue alone (
Placuna Lightfoot, 1786
Anomia placenta Linnaeus, 1758: 703. Type locality: unknown.
Placuna placenta.
Placuna (Placuna) placenta.
CUF-NKNY-B22 (19L+18R shells; Figs
Sandy mud in intertidal zones and shallow waters down to 35 m depth, in quiet waters of lagoons, protected bays, and mangrove areas, or near estuaries (
Indian Ocean; Indo-West Pacific, from Japan to Australia (
Gulf of Thailand and Andaman Sea (
This species differs from its similar species, Placuna ephippium (Philipsson, 1788), by having an almost circular shell and a right valve bearing a hinge plate with arrowhead-shaped lamellar teeth with the posterior ridge distinctly longer than the anterior one (
Volachlamys Iredale, 1939
Pecten singaporinus
Sowerby II, 1842: 74, pl. 13, fig. 55; pl. 14, fig. 71. Type locality: Singapore.
Volachlamys singaporina.
CUF-NKNY-B07 (32L+32R shells; Figs
Byssally attached under coral boulders and rocks, on sand and sandy mud in intertidal zones down to 22 m depth (
Indo-West Pacific, from China to Australia (
Gulf of Thailand and Andaman Sea (
This species differs from its similar species, Volachlamys tranquebaria (Gmelin, 1791) and V. hirasei (Bavay, 1904), by having square and well-defined 18–24 ribs with wider interspaces between the ribs (
Pegophysema Stewart, 1930
Loripes bialata Pilsbry, 1895: 133–134, pl. 3, figs 13, 14. Type locality: Inland Sea, Japan.
Anodontia
(?Pegophysema) bialata.
Pegophysema bialata.
Muddy bottoms and sandy mud among weed in intertidal zones down to 60 m depth (
Indian Ocean; Indo-West Pacific, from Japan to Malaysia (
Gulf of Thailand (
This species differs from its similar species, Pegophysema philippiana (Reeve, 1850), by having a ligament that is shallowly inset and an absence of secondary pallial attachment scars (
Geloina Gray, 1842
Cyrena bengalensis Lamarck, 1818: 554. Type locality: Bengal.
Polymesoda (Geloina) bengalensis.
Polymesoda bengalensis.
Geloina bengalensis.
CUF-NKNY-B31 (2L+3R shells; Figs
In intertidal zones, river deltas, estuaries, mud flats, and in mangrove areas (
Bay of Bengal; Indo-West Pacific, from Taiwan to Indonesia (
Gulf of Thailand and Andaman Sea (
This species is recognised based on the descriptions and figures in
Lutraria Lamarck, 1799
Mactra complanata Gmelin, 1791: 3261. Type locality: the Indian Ocean.
Lutraria (Lutrophora) cf. complanata.
Lutraria complanata.
Lutraria (Lutrophora) complanata.
Lutraria (Goniomactra) complanata.
Lutraria (Lutropbora) complanata
[sic].
CUF-NKNY-B29 (1L+2R shells; Figs
Sandy and muddy sand in subtidal zones from a depth of 8–20 m (
Indian Ocean; Indo-West Pacific, from South China to Indonesia (
Gulf of Thailand (
This species is recognised based on the descriptions and figures in
Mactra pellucida
Gmelin, 1791: 3260–3261. Type locality: “Guinea coast.”
Standella pellucida.
Meropesta pellucida.
CUF-NKNY-B30 (1L+1R shells; Figs
Fine sand and mud in intertidal zones down to 4 m depth, in lagoons, and at the fringe of mangrove areas (
Arabian Gulf and Indian Ocean; Indo-West Pacific, from Japan to Australia (
Gulf of Thailand and Andaman Sea (
This species is recognised based on the descriptions and figures in
Tellinides Lamarck, 1818
Tellina conspicua
Hanley, 1846b: 293, pl. 58, fig. 100. Type locality: unknown.
Tellina (Tellinides)
sp.
Tellinides conspicuus.
CUF-NKNY-B04 (33L+40R shells; Figs
Shallow water (
Indo-West Pacific, from southern China to New Guinea (
Gulf of Thailand (
Tellina (Tellinides) sp. in
Joannisiella Dall, 1895
Cyrenoidea oblonga
Hanley, 1846a: 10 (plate explanation). Type locality: Philippines.
Diplodonta (Joannisiella) oblonga.
Cycladicama oblonga.
Joannisiella oblonga.
CUF-NKNY-B09, B17 (59L+66R shells; Figs
Muddy bottom with soft clay, muddy sediments on mud flats, and in the shallow waters from intertidal zones down to 36 m depth (
Indo-West Pacific, from Japan to Indonesia and the Philippines (
Gulf of Thailand (
This species is characterised by its elongate, ovate-triangular shaped, and posteriorly grooved shell (
Dosinia Scopoli, 1777
Dosinia dilecta
A. Adams, 1856: 224. Type locality: Malacca.
Dosinia (Dosinella) dilecta.
CUF-NKNY-B10 (2L+5R shells; Figs
Soft clay and mud bottoms in subtidal zones at a depth from 5 to 20 m (
Indo-West Pacific, from southern China to Indonesia (
Gulf of Thailand and Andaman Sea (
This species is recognised based on the descriptions and figures in
Venus undulata Born, 1778: 54–55. Type locality: unknown.
Tapes (Paratapes) undulatus.
Paphia undulata.
Paphia cf. undulata.
Paphia (Paphia) undulata.
Neotapes undulata.
Paphia (Neotapes) undulata.
Paratapes undulatus.
Paratapes undulata.
CUF-NKNY-B12 (2L shells; Figs
Fine sandy sediments and mud as well as silty clay bottoms in intertidal to subtidal zones at a depth of 1–50 m (
Red Sea and Indian Ocean; Indo-West Pacific, from Japan to Australia (
Gulf of Thailand and Andaman Sea (
Despite having no colour and patterns, the elongate-oval and inequilateral shell shape with growth lines as well as slightly oblique and somewhat undulating commarginal grooves on outer surface of the specimens conform to the characters of this species (
Venus lamellata Röding, 1798: 183. Type locality: the East Indian Seas.
Venus tiara Dillwyn, 1817: 162. Type locality: the East Indian Seas.
Venus calophylla Philippi, 1836: 229–230, pl. 8, fig. 2 Type locality: the Chinese Sea.
Chione (Circomphalus) calophylla.
Callanaitis calophylla.
Placamen tiara.
Bassina calophylla.
Placamen calophyllum.
Placamen lamellatum.
Clausinella calophylla.
Clausinella tiara.
CUF-NKNY-B28 (1R shell; Figs
Muddy sand, sand, and shell gravels from intertidal zones down to 100 m depth (
Arabian Gulf and Indian Ocean; Indo-West Pacific, from Japan to Indonesia (
Gulf of Thailand and Andaman Sea (
This species differs from its similar species, Placamen chloroticum (Philippi, 1849), by having a somewhat shallower and trigonal pallial sinus as well as more widely spaced and more raised commarginal lamellae (
Corbula Bruguière, 1797
Corbula fortisulcata
Smith, 1879a: 819–820, pl. 50, fig. 23, 23b. Type locality: the Andaman Islands.
Corbula (Corbula) fortisulcata.
Corbula (Notocorbula) cf. fortisulcata.
Corbula (Notocorbula) fortisulcata.
CUF-NKNY-B19 (154 shells; Figs
Fine sand, sandy mud and muddy bottoms at intertidal to sublittoral zones at a depth from 1 to 70 m (
Indian Ocean; Indo-West Pacific, from Taiwan to Australia (
Gulf of Thailand and Andaman Sea (
This species differs from its similar species, Corbula tunicata Reeve, 1843, by having a weaker keel on the juvenile shell part (
CUF-NKNY-B26 (112 shells; Figs
Mostly present in intertidal zones, estuarine and brackish habitats (
This genus is mostly distributed in the Indian Ocean and Indo-West Pacific, except for the species Potamocorbula adusta (Reeve, 1844), which is recorded only from West Africa (
These specimens are assigned to Potamocorbula based on the descriptions in
Martesia Sowerby I, 1824
Pholas striatus Linnaeus, 1758: 669. Type locality: southern Europe.
Pholas (Martesia) striata.
Martesia striata.
Martesia (Martesia) striata.
CUF-NKNY-B14 (8L+8R shells; Figs
Bored in old wood pilings, waterlogged tree trunks, and in driftwood but rarely in astreid corals, in soft rocks, or mangroves Rhizophora stylosa; from intertidal zones down to 20 m depth (
Cosmopolitan (
Gulf of Thailand and Andaman Sea (
This species is recognised based on the descriptions and figures in
Pholas orientalis
Gmelin, 1791: 3216. Type locality: Siam [Thailand] and Tranquebar.
Pholas siamensis
Spengler, 1792: 88–89. Type locality: the Gulf of Thailand, the mouth of the river Qweda, where it goes up to Alastav.
Pholas (Monothyra) orientalis.
CUF-NKNY-B05 (26L+73R shells; Figs
Boring down to 50 cm depth in peat, soft rocks, stiff clay, or sticky and soft sandy-mud bottoms rich in silt and detritus, often near river mouths, from intertidal and sublittoral zones at a depth from 1 to 30 m (
Indian Ocean; Indo-West Pacific, from Taiwan to Australia (
Gulf of Thailand and Andaman Sea (
This species is recognised based on the descriptions and figures in
CUF-NKNY-B14-4 (83 tube pieces; Fig.
Boring into submerged wood and other plant material (
The calcareous burrows have a septum dividing the cavity in half, indicating that these burrows belong to the shipworm family Teredinidae (e.g.,
Cultellus Schumacher, 1817
Solen maximus Gmelin, 1791: 3227. Type locality: Nicobar.
Solen lacteus Spengler, 1794: 94–95. Type locality: Nicobar.
Cultellus lacteus.
Cultellus maximus.
Deeply (down to 40 cm) buried in soft mud at seaward fringes of mangrove forests or intertidal zones down to 3 m depth (
Indian Ocean; Indo-West Pacific, from Taiwan to Borneo Island (
Gulf of Thailand and Andaman Sea (
Due to the large size and oblong-elliptical shape of shells (
Solen minimus Gmelin, 1791: 3227. Type locality: Tranquebar.
Siliqua minima.
Siliqua cf. minima.
Siliqua (Neosiliqua) minima.
CUF-NKNY-B16 (6L+6R shells; Figs
Sand and mud bottoms from intertidal zones down to 30 m depth (
Indian Ocean; Indo-West Pacific, from Japan to the Philippines (
Gulf of Thailand (
This species is recognised based on the descriptions and figures in
Dentalium Linnaeus, 1758
Dentalium variabile
Deshayes, 1826: 352–353, pl. 16, fig. 30. Type locality: possibly India.
Dentalium (Lentigodentalium) variabile. Dey and Ramakrishna 2007: 162, 257.
CUF-NKNY-O01 (48 shells; Figs
Mud bottoms from a depth of 10–75 m (
Indo-West Pacific, from Japan to Reunion Island and New Caledonia. Records of fossils from the Quaternary in Thailand (
Gulf of Thailand (
This species is recognised based on the descriptions and figures in
Subphylum Crustacea Brünnich, 1772
Class Malacostraca Latreille, 1802
Order Decapoda Latreille, 1802
Thalassina Latreille, 1806
CUF-NKNY-O09 (130 pieces; Figs
Littoral and sublittoral zones, mangrove swamps and forests, and edges of estuaries (
Indo-West Pacific, from Japan to Australia (
These specimens are assigned to Thalassina based on descriptions in
Subfamily Amphibalaninae Pitombo, 2004
Fistulobalanus Zullo, 1984
Balanus amphitrite var. kondakovi Tarasov & Zevina, 1957: 179, 191, fig. 76a–d. Type locality: Japan.
Balanus kondakovi.
Balanus amphitrite kondakovi.
Fistulobalanus kondakovi.
CUF-NKNY-O06-1 (217 individuals; Figs
Attached to hard substrates, mainly shells of oysters and gastropod molluscs and stalks of seaweed, as well as wooden piles and supports, bamboo, various objects installed under water on muddy beds for oyster culture, and buoys, in freshened closed inner parts of bays and estuarine coastal areas, from intertidal to subtidal zones (
Indian Ocean; Indo-West Pacific, from Japan to New Zealand (
Gulf of Thailand (
The subfamily Amphibalaninae was erected to incorporate most of the species under the Balanus amphitrite complex/group (
cf.Lepas tintinnabulum Linnaeus, 1758: 668. Type locality: Amboina, Indonesia [lectotype designation by
cf.Balanus (Megabalanus) tintinnabulum tintinnabulum.
cf.Balanus tintinnabulum var. tintinnabulum.
cf.Balanus tintinnabulum.
cf.Megabalanus tintinnabulum.
CUF-NKNY-O06-2 (2 individuals; Figs
Attached on low exposed rocky shores in littoral areas, ship bottoms, and floating pontoons (
Cosmopolitan (
Andaman Sea (
These specimens are tentatively identified as belonging to Megabalanus tintinnabulum based on the descriptions and figures in
Class Echinoidea Schumacher, 1817
Order Camarodonta Jackson, 1912
Temnotrema Agassiz, 1864
Pleurechinus siamensis Mortensen, 1904: 79–82, pl. 1, figs 2, 7, 11, 20; pl. 2, figs 2, 9, 14, 15, 22; pl. 6, figs 16, 36; pl. 7, figs 14, 44, 53. Type locality: Koh Mesan, 3–15 fathoms; Koh Chuen, 15–38 faths.; Koh Kram, 20–30 faths.; Koh Kahdat, 10 faths.
Temnotrema siamense.
Temnotrema siamensis.
CUF-NKNY-O02 (23 shells; Figs
Coarse and high energy subtidal sand from a depth of 5–350 m (
Persian Gulf and Indian Ocean; Indo-West Pacific, from South China Sea to Australia (
Gulf of Thailand and Andaman Sea (
This species is recognised based on the descriptions and figures in
Subphylum Vertebrata Lamarck, 1801
Class Chondrichthyes Huxley, 1880
Subcohort Selachimorpha Nelson, 1984
Superorder Galeomorphii Compagno, 1973
Order Carcharhiniformes Compagno, 1977
Carcharhinus Blainville, 1816
cf.Gillisqualus amblyrhynchoides Whitley, 1934: 189–191, text-fig. 4. Type locality: Cape Bowling Green, Queensland.
cf.Carcharhinus amblyrhynchoides.
CUF-NKNY-S3-2 (Fig.
The crown of CUF-NKNY-S3-2 is triangular and erect with fine serrations and displays well-developed heels mesially and distally. Its lingual face is distinctly more convex than the labial one. Its base presents a damaged lingual face.
Tropical, inshore and offshore, coastal-pelagic species, found over the continental and insular shelves (
Gulf of Aden and Indian Ocean; Indo-West Pacific, from southern China to Australia (
Gulf of Thailand and Andaman Sea (
The specimen CUF-NKNY-S3-2 represents an anterior upper tooth. Several species of Carcharhinus have similar upper teeth in terms of morphology. Additional teeth and larger assemblages are needed for a more precise identification. Nevertheless, the tooth most resembles the upper teeth of C. amblyrhynchoides (
cf.Carcharias (Prionodon) amblyrhynchos Bleeker, 1856: 467–468. Type locality: Java Sea near Solombo Island.
cf.Carcharhinus amblyrhynchos.
CUF-NKNY-S3-10 (Fig.
The crown of CUF-NKNY-S3-10 displays a rather narrow main cusp with well-developed heels. The main cusp is regularly serrated, with an almost straight mesial edge and a distal one that is slightly concave. It is thus inclined distally. The labial side of the main cusp is nearly flat, whereas the lingual one is convex. Both the mesial and distal heels of the crown are poorly preserved and their serration pattern cannot thus be observed. The base of the root is concave and the nutritive groove on the bulged lingual face is poorly developed or heavily worn. The labial face of the root is nearly flat.
Continental and insular shelves and adjacent oceanic waters (
Indo-western to Central Pacific (
Gulf of Thailand and Andaman Sea (
The general shape of the crown, the regular serration of the main cusp, and the arched root are reminiscent of C. amblyrhynchos (
cf.Carcharias (Prionodon) leucas Valenciennes in Müller & Henle, 1839: 42–43. Type locality: Antilles.
cf.Carcharhinus leucas.
CUF-NKNY-Q04 (Fig.
Carcharhinid shark teeth - Carcharhinus cf. leucas A–I specimen CUF-NKNY-Q04 in A lingual B labial and C–F different apical views G–I close-ups on the serrations of the distal cutting edge at the level of G distal heel and mesial cutting edge at the level of H upper part of the cusp and I heel. J–N specimen CUF-NKNY-SA-1 in J lingual K labial L mesial M distal and N apical views.
Crowns show well-developed serrations, becoming larger and more complex in the basal part of the distal side of the crown. In labial or lingual view, the mesial side is almost straight, whereas the distal one is concave in its lower third. The outline of the base of the crown is more concave on the lingual face than on the labial one. The root is deep, slightly concave at its base, and does not display a nutritive groove in lingual view.
Close inshore in reef-associated marine habitats, mostly in water less than 30 m depth (
Cosmopolitan in tropical and subtropical seas, but also reported from estuaries and rivers, tolerant of freshwater conditions (
Gulf of Thailand and Andaman Sea (
Teeth of C. amboiensis are very similar to those of C. leucas so that it is very difficult to differentiate them (
cf.Carcharias (Prionodon) sorrah Valenciennes in Müller & Henle, 1839: 45–46, pl. 16. Type locality: Java.
cf.Carcharhinus sorrah.
CUF-NKNY-3.1 (Fig.
Carcharhinid shark teeth - Carcharhinus cf. sorrah A–G specimen CUF-NKNY-3.1 A lingual B apical C labial D mesial and E distal views F, G close-ups of the serration F on the distal heel and G on the middle part of the cusp mesial cutting-edge H–N specimen CUF-NKNY-3.2 H lingual I apical J labial K mesial and L distal views M close-up of the serration on the lower part of the mesial cutting-edge and N close-up of the serration between the heel and the base of the distal cutting edge.
The crown is compressed labio-lingually. The labial face is slightly flatter than the lingual one. The cusp is inclined distally and presents a notch on its distal part. The serrations do not reach the apex of the main cusp and are enlarged, becoming more complex basally, especially on the distal heel. The mesial edge of the crown is almost straight in labial or lingual view. The base of the root is slightly concave in lingual or labial view. There is a well-developed groove with a nutritive foramen at the base of the root in lingual view.
Coastal, shallow-water zones of the continental and insular shelves, primarily around coral reefs at intertidal zones down to 73 m depth (
Red Sea and Indian Ocean; Indo-West Pacific, from China to Australia (
Gulf of Thailand and Andaman Sea (
Some upper teeth of C. sorrah appear to display a mesial cutting edge slightly more convex than on our specimens, but this character is known to depend on ontogenetic stages and the position of the teeth in the jaw (e.g.,
CUF-NKNY-16.1 (Fig.
The specimens CUF-NKNY-16.1, CUF-NKNY-S3-4, CUF-NKNY-S3-8, and CUF-NKNY-S4-7 display a narrow main cusp that is inclined lingually. Their labial face is flatter than the lingual one. The serrations are well-developed in the upper two-third of the cusp. The serrations appear to be very fine on the mesial and distal heels in CUF-NKNY-16.1, CUF-NKNY-S3-4, and CUF-NKNY-S3-8, but the serrations are damaged in CUF-NKNY-S4-7. The root is well preserved only in CUF-NKNY-S3-4 and CUF-NKNY-S3-8, both of which display a slightly arched base, a moderately bulged lingual face with a nutritive foramen in its centre in CUF-NKNY-S3-4 and a faint nutritive groove in CUF-NKNY-S3-4. The specimen CUF-NKNY-S2 is asymmetric, with a mesial heel almost twice as elongated as the distal one and displays a sigmoid main cusp in labial or lingual view as well as in mesial or distal view, separated from the distal heel by a notch. The heels are serrated, but the main cusp is smooth. This tooth appears quite bulbous in mesial or distal view, being less compressed labio-lingually than the specimens described above. There is a well-developed nutritive groove on the root in lingual view, forming a basal notch in labial view.
Carcharhinid shark teeth - Carcharhinus spp. A–G specimen CUF-NKNY-16.1 in A lingual B labial C mesial D distal and E, F apical views G close-ups of the serration on the upper part of the cusp mesial cutting edge in lingual view H–L specimen CUF-NKNY-S2 in H labial I apical J lingual K mesial and L distal views.
A heavily worn tooth (CUF-NKNY-S3-7) is better attributed to an upper tooth. The lingual and distal faces of the crown are strongly damaged and a part of the distal end of the root is missing. The serration is only preserved in the middle part of the mesial cutting edge and appears to be quite regular. The root has a basal face slightly arched with a well-developed nutritive groove on its lingual face, forming a notch at the base of the root in labial view.
Another upper tooth, CUF-NKNY-S1, displays a crown with a quite coarse, irregular serration pattern nearly reaching the apex of the main cusp. The latter is bent lingually and slightly inclined distally. Its root shows a well-developed nutritive groove in lingual view, forming a notch at the base of the root in labial view. Apart from this notch, the base is almost straight.
Lower teeth of C. amblyrhynchos (C. wheeleri in
The sigmoid crown of the specimen CUF-NKNY-S2 is reminiscent of the posterior lower teeth of C. borneensis and C. tjutjot (
There are 27 species of the genus Carcharhinus reported from the Southeast Asian region (
CUF-NKNY-8.2 (Fig.
Carcharhinid shark teeth - Glyphis sp. A–H specimen CUF-NKNY-14, lower tooth in A lingual B labial C mesial D distal and E apical views F–H close-ups on the serration F on the distal heel, G at the base of the cusp distal cutting-edge and H in the middle part of the cusp mesial cutting-edge I–M specimen CUF-NKNY-S1-2, lower anterior tooth in I lingual J labial K mesial L distal and M apical views.
Many teeth are poorly preserved. The crown of the upper teeth is triangular in outline, with a concavity at the base on both the mesial and distal sides in labial and lingual view, although the distal one is better marked, especially in anterior teeth (CUF-NKNY-S5-7). The serrations are quite fine and homogeneous in size along the cutting edges. The crown is strongly compressed labio-lingually and may be slightly curved lingually. When being broken, the crown displays a pulp cavity compressed labio-lingually, indicating an orthodont tooth histology (CUF-NKNY-SE-11). The base of the root is slightly concave in labial or lingual view. A well-developed nutritive groove and/or a nutritive foramen may be present on the lower half of the lingual side of the root.
The lower teeth may reach 40 mm in height. They are narrower and less compressed labio-lingually than the upper ones. The enameloid is smooth and the labial face of the crown is flatter than the lingual one. The main cusp is inclined lingually, sometimes with a sigmoid outline (CUF-NKNY-S4-2, CUF-NKNY-S4-5). Three different crown morphologies are noted. (1) On the specimens CUF-NKNY-S1-1, CUF-NKNY-S1-2, and CUF-NKNY-S1-4, the crown is devoid of heels and the tip of the main cusp is spearhead-shaped, the latter being regularly serrated, whereas the rest of the crown is smooth. (2) The specimens CUF-NKNY-S4-1 and CUF-NKNY-S4-4 have a narrow and upright triangular main cusp devoid of serration, showing a tiny accessory cusplet on each side of the main cusp in CUF-NKNY-S4-4 or only lingually in CUF-NKNY-S4-1. (3) On the specimen CUF-NKNY-S3-6, the main cusp is also upright, narrow, triangular in shape, and serrated on their mesial and distal edges. Well-developed heels are present on each side of the main cusp, separated from the latter by a notch. The heel is sometimes less marked on the mesial side (CUF-NKNY-S3-1). The heels display less developed serration than on the main cusp. Many teeth belonging to this morphotype display a broken apex of the main cusp (CUF-NKNY-14).
The root displays a bulged lingual face. It is more massive and more arched in spearhead-shaped teeth than in heeled ones. There is a nutritive groove in the lingual side of the root with a nutritive foramen in its middle part that can be observed in most of the teeth. The specimen CUF-NKNY-S1-1 displays a double groove.
Upper anterior teeth (CUF-NKNY-Q03) are more erect and narrower than the lateral ones (CUF-NKNY-8.2). Lower teeth with a spearhead-shaped apex correspond to the larger teeth in our sample, in agreement with the fact that this morphology is known only in anterior teeth of adult specimens of Glyphis glyphis and G. garricki. However, lateral teeth of these species display serrated heels and teeth of juveniles can display a pair of tiny lateral cusplets (
The genus is specific to the Indo-West Pacific tropical region and often referred as “river shark” due to its habitat in or nearby rivers and estuaries. They are quite rare, hence difficult to study. Five living species are known (
cf.Carcharias (Scoliodon) laticaudus Müller & Henle, 1838: 28–29, pl. 8. Type locality: India.
cf.Scoliodon laticaudus.
CUF-NKNY-S3–S5 (Fig.
Carcharhinid shark teeth - Scoliodon cf. laticaudus A–E specimen CUF-NKNY-S3, lower anterolateral tooth in A lingual B labial C mesial D distal and E apical views F–J specimen CUF-NKNY-S4, upper anterior-anterolateral tooth in F lingual G labial H mesial I distal and J apical views K–O specimen CUF-NKNY-S5, parasymphyseal tooth in K lingual L labial M mesial N distal and O apical views.
The specimen CUF-NKNY-S3 is a small and elongated tooth with a low crown and a worn off root. The mesial cutting edge is concave and smooth and continues along the mesial heel. The distal edge of the crown is convex and separated by a notch from a distinct distal heel.
The specimen CUF-NKNY-S4 is a well-preserved tooth, with a crown strongly curved distally. The mesial cutting edge is sinusoid, starting convex, then becoming concave towards the apex. The apex of the crown overhangs distally the basal part of the tooth. The distal cutting edge is also sinusoid, though less so than the mesial one, and it is separated by a distinct notch from a well-developed distal heel. The enameloid of the crown extends more basally on the labial side of the tooth. The root is thick and the lobes run rather horizontally. It bears a well-developed and deep nutritive groove in the centre.
The cusp of the specimen CUF-NKNY-S5 is strongly sigmoid in labial and lingual view, and similar to that of CUF-NKNY-S4, but its cusp is narrower and less wide at the base, with more apparent mesial heels. The cutting edge is smooth and does not reach the apex of the cusp on its mesial side. The heels of the crown display faint serrations. The root is asymmetric and projected lingually and distally. There is a well-defined groove distally on the lingual side of the basal face, forming a deep notch in apical view.
Tropical zones of continental and insular shelves close to inshore, frequently in rocky areas (
Indian Ocean; Indo-West Pacific, from Japan to Indonesia (
Andaman Sea (
The three teeth best fit the dentition of the modern species S. laticaudus (spadenose shark). The specimen CUF-NKNY-S5 has a slender sigmoidal cusp and its mesial cutting edge does not reach the apex. It displays an asymmetric root, corresponding perfectly to a parasymphyseal tooth of a male specimen (
It may be mentioned that the specimen CUF-NKNY-S3 also resembles that of the lower anterolateral teeth of other common sharks in Southeast Asia (
CUF-NKNY-S3-3, CUF-NKNY-S4-3, CUF-NKNY-S5-3, CUF-NKNY-SC-2, CUF-NKNY-SC-7, CUF-NKNY-SD-4, CUF-NKNY-SD-5, CUF-NKNY-SD-11, CUF-NKNY-SE-8, CUF-NKNY-SE-16 (10 teeth).
These teeth are poorly preserved. The crown is generally triangular, more or less narrow, and symmetric with serration incompletely preserved. The root is broken away or does not display the details of its vascularisation pattern.
The presence of triangular serrated crowns suggests that most of the teeth belong to upper ones of Carcharhinus and/or Glyphis, but their poor preservation does not allow a more precise identification. The specimen CUF-NKNY-SC-7 may represent a lower tooth of C. leucas/C. amboinensis, but without the root and the base of the crown preserved, this is impossible to ascertain.
Pastinachus Rüppell, 1829
CUF-NKNY-7.1 (Fig.
Dasyatid ray teeth - Pastinachus sp. A–F specimen CUF-NKNY-7.1 in A lingual B labial C, F profile D occlusal and E basal views G–L specimen CUF-NKNY-7.2 in G lingual H labial I, L profile J occlusal and K basal views M–R specimen CUF-NKNY-8.1 in M lingual N labial O, R profile P occlusal and Q basal views.
The crown is hexagonal to diamond-shaped in apical view, longer mesio-distally than labio-lingually. The crown surface is rather smooth to heavily pitted. The labial face of the crown displays a salient horizontal bulge. There is a well-developed horizontal groove in the basal part of the crown on the lingual face. The vascularisation of the teeth is holaulacorhize. There is a row of small foramina positioned under the crown on the labial face and between one and four foramina present in the groove separating the two branches of the root in basal view.
Heavily pitted crowns probably belong to non-functional teeth (
CUF-NKNY-2.1 (Fig.
Trichiuridae indet. A–F specimen CUF-NKNY-2.1, anterior tooth in A, B lateral C anterior D posterior and E apical views F close-up of the tip of the tooth G–K specimen CUF-NKNY-2.2, anterior tooth in G, H lateral I anterior J posterior and K apical views L–P specimen CUF-NKNY-18.2, lateral tooth in L, M lateral N anterior O posterior and P apical views.
Labiolingually flattened teeth seem to thin out at their mesial edge. They are covered with elongated and fine striation. This striation becomes coarser basally and distally on the more elongated specimens (specimens CUF-NKNY-2.1 and CUF-NKNY-2.2). The latter two teeth are strongly curved distally with a concave distal edge and the more completely preserved specimen CUF-NKNY-2.1 bears an apical barb. The specimen CUF-NKNY-18.2 has a curved mesial margin, whereas the distal one is vertical and straight.
The two strongly curved teeth (specimens CUF-NKNY-2.1 and CUF-NKNY-2.2) represent fang-like features from the front of the jaw, while the specimen CUF-NKNY-18.2 comes from a rather distal position. This latter tooth resembles somewhat the lateral teeth of Sphyranea (barracuda, e.g.,
Johnius Bloch, 1793
Thick otolith with a smooth external surface, whereas the internal surface bears a sulcus characteristic of the genus. The ostium is shallow, vertically positioned, higher than long, and it widens ventrally. The anterior and horizontal portion of the cauda is short and shallow, then opening posteriorly into a deep caudal funnel with an external circular shape.
Otoliths of Johnius are unique and have distinct characteristics that make them easily distinguishable from those of other sciaenids or teleosts (
Based on the survey of mid-Holocene marine faunas from the clay pit of Nakhon Nayok Province in Thailand, many fossils of molluscs together with other invertebrates and vertebrates have been found in the Bangkok clay layer at a depth of ~ 5–7 m below the surface. The faunal assemblages, especially molluscs (Table
Molluscan species assemblages from the Bangkok Clay deposits of Ongkharak in Nakhon Nayok recovered in the present study and from other sites retrieved from previous literature (indicated by an asterisk). NA = data not available.
Class | Species in this study | Lower Central Plain and Chao Phraya delta ( |
Lower Central Plain of Bangkok and inland of Phetchaburi coast ( |
Ban Praksa, Samut Prakan ( |
Sam Roi Yot National Park, Phetchaburi ( |
Habitat | Substrate preference |
---|---|---|---|---|---|---|---|
Gastropoda | 1. Homalopoma cf. sangarense | – | – | – | – | Sublittoral | Sand, hard |
2. Neripteron violaceum | – | – | – | – | Intertidal, mangrove | Mud, hard | |
3. Nerita articulata | * | – | – | – | Intertidal, mangrove | Mud, hard | |
4. Cerithidea obtusa | – | * | – | – | Intertidal, mangrove | Mud, hard | |
5. Pirenella incisa | – | – | – | – | Intertidal, mangrove | Mud | |
6. Telescopium telescopium | – | – | – | – | Intertidal, mangrove | Mud | |
7. Eunaticina papilla | – | * | – | – | Intertidal–sublittoral | Sand | |
8. Natica stellata | – | * | – | – | Sublittoral | Sand | |
9. Natica vitellus | – | * | – | – | Intertidal– sublittoral | Sand, mud | |
10. Paratectonatica tigrina | * | * | * | * | Intertidal– sublittoral | Sand, mud | |
11. Ergaea walshi | – | * | – | – | Intertidal– sublittoral | Hard | |
12. Bufonaria rana | – | – | – | – | Sublittoral | Sand, mud | |
13. Merica elegans | – | – | – | – | Sublittoral | Sand, mud | |
14. Scalptia scalariformis | – | * | – | – | Sublittoral | Sand, mud | |
15. Pseudoneptunea varicosa | – | * | – | – | Sublittoral | NA | |
16. Brunneifusus ternatanus | * | – | – | – | Sublittoral | Sand, mud | |
17. Nassarius micans | – | * | – | – | Intertidal– sublittoral | Sand | |
Gastropoda | 18. Nassarius siquijorensis | – | * | – | * | Intertidal– sublittoral | Sand, mud |
19. Chicoreus capucinus | * | – | – | – | Intertidal, mangrove | Sand, mud, hard | |
20. Indothais gradata | * | – | – | – | Sublittoral | Hard | |
21. Indothais lacera | – | * | – | – | Intertidal– sublittoral | Mud, hard | |
22. Murex trapa | * | * | – | * | Sublittoral | Sand, mud | |
23. Maoritomella vallata | – | * | – | – | Sublittoral | NA | |
24. Pseudoetrema fortilirata | – | * | – | – | Sublittoral | Sand, mud | |
25. Turricula javana | * | * | – | * | Intertidal– sublittoral | Sand, mud, hard | |
26. Paradrillia melvilli | – | * | – | – | Sublittoral–upper bathyal | NA | |
27. Inquisitor vulpionis | – | * | – | – | Sublittoral | Sand | |
28. Comitas ilariae | – | – | – | – | Sublittoral | Sand | |
29. Duplicaria tricincta | – | * | – | – | Sublittoral | Sand, mud | |
30. Granuliterebra bathyrhaphe | – | * | * | – | Intertidal– sublittoral | Sand, mud | |
31. Pristiterebra miranda | – | * | – | – | Sublittoral | NA | |
32. Architectonica perdix | – | * | – | * | Sublittoral | Sand, mud | |
33. Cylichna modesta | – | * | – | – | Sublittoral | Sand, mud | |
34. Ellobium aurisjudae | – | * | – | – | Intertidal, mangrove | Sand, mud, hard | |
35. Cassidula nucleus | – | * | – | – | Intertidal, mangrove | Mud, hard | |
Bivalvia | 1. Jupiteria puellata | – | * | * | – | Sublittoral | Sand, mud |
2. Saccella mauritiana | – | * | – | – | Sublittoral | Sand, mud, hard | |
3. Anadara inaequivalvis | – | * | – | * | Intertidal–sublittoral | Sand, mud | |
4. Anadara indica | – | * | – | * | Intertidal– sublittoral | Sand, mud | |
5. Tegillarca granosa | * | * | – | * | Intertidal, mangrove | Mud | |
6. Tegillarca nodifera | – | – | – | – | Intertidal– sublittoral, mangrove | Sand, mud | |
7. Estellacar olivacea | * | * | – | – | Intertidal– sublittoral, mangrove | Sand, mud | |
8. Noetiella pectunculiformis | – | * | – | – | Intertidal– sublittoral, mangrove | Sand, mud | |
9. Magallana cf. gigas | – | * | – | * | Intertidal– sublittoral | Mud, hard | |
10. Placuna placenta | – | * | * | * | Intertidal– sublittoral | Sand, mud | |
11. Volachlamys singaporina | – | – | – | – | Intertidal– sublittoral | Sand, mud, hard | |
12. Pegophysema bialata | – | – | – | – | Intertidal– sublittoral | Sand, mud | |
13. Geloina bengalensis | – | * | – | – | Intertidal, mangrove | Mud | |
14. Lutraria complanata | – | * | – | – | Sublittoral | Sand, mud | |
15. Standella pellucida | – | * | – | – | Intertidal– sublittoral, mangrove | Sand, mud | |
16. Tellinides conspicuus | – | – | – | – | Sublittoral | NA | |
17. Joannisiella oblonga | * | * | – | * | Intertidal– sublittoral | Mud | |
18. Dosinia dilecta | – | * | – | * | Sublittoral | Mud | |
19. Paratapes undulatus | * | * | * | * | Intertidal– sublittoral | Sand, mud | |
20. Placamen lamellatum | – | * | – | – | Intertidal– sublittoral | Sand, mud | |
21. Corbula fortisulcata | – | * | – | * | Intertidal–sublittoral | Sand, mud, hard | |
22. Potamocorbula sp. | NA | NA | NA | NA | Intertidal | NA | |
23. Martesia striata | – | * | – | – | Intertidal–sublittoral | Hard | |
24. Pholas orientalis | – | * | – | – | Intertidal–sublittoral | Sand, mud, hard | |
25. Teredinidae indet. | NA | NA | NA | NA | Intertidal–sublittoral | Hard | |
26. Cultellus maximus | – | * | – | – | Intertidal–sublittoral, mangrove | Mud | |
27. Siliqua minima | – | * | – | – | Intertidal–sublittoral | Sand, mud | |
Scaphopoda | 1. Dentalium variabile | – | * | * | – | Sublittoral | Mud |
Most of the marine and mangrove shells were found at a depth of 2.2 m below the uppermost part of a marine clay layer. The carbon-14 dating analysis indicates a mid-Holocene age for this level as being approximately 5,900–5,300 cal yr BP, whereas charcoal material was found at a greater depth of 2.2–4.6 m, spanning approximately an age from 8,800 to 5,700 cal yr BP (Table
The vertebrate fauna is dominated by cartilaginous fishes, among which the family Carcharhinidae is most common (Table
Fish remains recovered from the Bangkok Clay deposits of Ongkharak in Nakhon Nayok.
Class Chondrichthyes | ||||
Order | Family | Species | No. | Material |
Carcharhiniformes | Carcharhinidae | Carcharhinus cf. amblyrhynchoides | 1 | tooth |
Carcharhinus cf. amblyrhynchos | 1 | tooth | ||
Carcharhinus cf. leucas | 4 | teeth | ||
Carcharhinus leucas/Carcharhinus amboinensis | 10 | teeth | ||
Carcharhinus cf. sorrah | 2 | teeth | ||
Carcharhinus spp. | 7 | teeth | ||
Glyphis sp. | 59 | teeth | ||
Scoliodon cf. laticaudus | 3 | teeth | ||
Carcharhinidae indet. | 10 | teeth | ||
Myliobatiformes | Dasyatidae | Pastinachus sp. | 3 | teeth |
Class Actinopterygii | ||||
Scombriformes | Trichiuridae | Trichiuridae indet. | 3 | teeth |
incertae sedis in Eupercaria | Sciaenidae | Johnius sp. | 1 | otolith |
We thank the following colleagues from the Department of Biology, Faculty of Science, Chulalongkorn University: Wichase Khonsue who led us to the locality and provided information on the sites, Somsak Panha who facilitated access to collection storage and working area, Arthit Polyotha for providing SEM images, and Kittipum Chansri and Buntika A. Butcher for providing access and taking photographs with a Leica M205C stereo light microscope. We also thank Fa-Is Jindewha, Sutan Saehan, Jirapan Sumpaothong, and Suwijak Pata for their assistance in the field, Santi Pailoplee (Department of Geology, Faculty of Science, Chulalongkorn University) for his help in generating the map, Mana Rugbumrung (Department of Mineral Resources) for his technical assistance and supports, and Thierry Backeljau (Royal Belgian Institute of Natural Sciences, Brussels) and Bernhard Hausdorf (Leibniz Institute for the Analysis of Biodiversity Change, Hamburg) for the access to the relevant literature. We are grateful to Montri Inthasaeng who allowed us to work at the site. Finally, we thank Jürgen Kriwet and Matthias Harzhauser for their comments on the first version of this manuscript.
The authors have declared that no competing interests exist.
No ethical statement was reported.
This research was supported by the Sci-Super VII grant, Faculty of Science, Chulalongkorn University (Grant No. Sci-Super VII_64_001, to KS and CS).
Conceptualization: PJ, LK, KS, CS, GC. Data curation: NN, SK, KS. Formal analysis: PJ, KS, NN, LK, SK, GC, TC. Funding acquisition: CS, KS. Investigation: CS, TC, NN, KS. Methodology: CS, TC, PJ, LK, GC, KS. Project administration: KS. Resources: NN, CS, KS. Validation: LK, PJ, GC, KS. Visualization: KS, LK, GC, PJ. Writing - original draft: KS, GC, PJ, LK. Writing - review and editing: PJ, LK, GC, KS.
Parin Jirapatrasilp https://orcid.org/0000-0002-5591-6724
Gilles Cuny https://orcid.org/0000-0001-7680-1697
László Kocsis https://orcid.org/0000-0003-4613-1850
Chirasak Sutcharit https://orcid.org/0000-0001-7670-9540
Kantapon Suraprasit https://orcid.org/0000-0002-3428-9549
All of the data that support the findings of this study are available in the main text.