Magallana cf. gigas ( Thunberg, 1793 )

Jirapatrasilp, Parin, Cuny, Gilles, Kocsis, László, Sutcharit, Chirasak, Ngamnisai, Nom, Charoentitirat, Thasinee, Kumpitak, Satapat & Suraprasit, Kantapon, 2024, Mid-Holocene marine faunas from the Bangkok Clay deposits in Nakhon Nayok, the Central Plain of Thailand, ZooKeys 1202, pp. 1-110 : 1-110

Magallana cf. gigas ( Thunberg, 1793)

Figs 12 E , 14 D

cf. Ostrea gigas Thunberg, 1793: 140 – 142 , pl. 6, figs 1 – 3. Type locality: Japan. Yokoyama 1927: 402.

cf. Crassostrea gigas . Tantanasiriwong 1979: 7. Nateewathana et al. 1981: 65. Poutiers 1998 a: 233, with in-text figs. Aungtonya et al. 1999: 375. Robba et al. 2002: 69, 71, pl. 5, fig. 3 a, b. Hylleberg and Kilburn 2003: 162. Beu et al. 2004: 154 – 156, fig. 9 d. Thach 2005: 257. Robba et al. 2007: 84 (appendix). Printrakoon et al. 2008: table 1. Huber 2010: 180, with in-text fig. Sanpanich 2011: table 2. Huber 2015: C 5155. Okutani 2017: 1183, pl. 483, fig. 7. Yang et al. 2017: 176, 178, fig. 685. Surakiatchai et al. 2018: table 6, pl. 3, fig. 6 a, b. Tudu et al. 2018: table 1.

cf. Crassostrea cf. gigas . Swennen et al. 2001: 45, 72, text-fig. 62, fig. 62.

cf. Crassostrea (Magallana) gigas . Lutaenko et al. 2019: 187 – 188, pl. 15, fig. a – f.

cf. Magallana gigas . Wells et al. 2021: 60.

Referred material.

CUF - NKNY - B 13 (130 L + 16 R shells; Figs 12 E , 14 D ).

Habitat.

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 ( Thach 2005; Huber 2015).

Distribution.

Cosmopolitan ( Huber 2015). Records of fossils from the Miocene to Holocene in Japan, New Zealand, Taiwan, and Thailand ( Robba et al. 2002; Beu et al. 2004; Surakiatchai et al. 2018).

Record in Thailand.

Gulf of Thailand and Andaman Sea ( Wells et al. 2021).

Taxonomic remarks and comparisons.

The cupped oysters in the subfamily Crassostreinae could not be identified at species level based on shell characters or soft tissue alone ( Salvi and Mariottini 2021). Therefore, we tentatively identify these specimens of giant cupped oysters as belonging to Magallana gigas , due to large and thick shells and the presence of this species in Thailand ( Wells et al. 2021).

Order Pectinida Gray, 1854

Superfamily Anomioidea Rafinesque, 1815

Figures

Figure 12. 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.

Figure 14. Bivalves A Tegillarca nodifera B Estellacar olivacea C Noetiella pectunculiformis D Magallana cf. gigas E Placuna placenta F Volachlamys singaporina.