Chelonia mydas (Linnaeus, 1758)

Figueroa, Alex, Low, Martyn E. Y. & Lim, Kelvin K. P., 2023, Singapore’s herpetofauna: updated and annotated checklist, history, conservation, and distribution, Zootaxa 5287 (1), pp. 1-378 : 67-69

Chelonia mydas (Linnaeus, 1758) — Native.

Testudo Mydas Linnaeus, 1758: 197 . Syntypes (3): UUZM 19 , 26 , 231 (not NRM and not UUZM 20 as in Smith & Smith [1979: 269]), according to Wallin (2001: 126); additionally, Bauer et al. (2013: 312) designated an unnumbered syntype in the MZUB, and NRM 5000 and 6880–82 were also designated as possible syntypes, according to Anders Rhodin (in Iverson, 2022: 16). Type locality: “[h]abitat ad insulas Pelagi: insulam Adscensionis &c.” (= The Pelagie Islands and Ascension Island); later restricted to “Insel Ascension” (= Ascension Island) by Mertens & M̧ller (1928: 23).

Green Turtle

( Figure 8B )

Singapore records.

“esculent turtle”— Crawfurd, 1856: 398.

Chelonia virgata — Ģnther, 1864: 53.

Chelone mydas — Hanitsch, 1898: 9.— Flower, 1899: 618.— Hanitsch, 1912b: 14.— Kobayashi, 1920: 394, 395, 296.

Chelonia mydas — Hughes et al., 1942: 115, 118.—Sharma, 1973: 234.— Gremli, 1988: 62.—K.K.P. Lim & L.M. Chou, 1990: 56.—K.K.P. Lim & F.L.K. Lim, 1992: 132, 151.—E.K. Chua, 1993: 113.—L.M. Chou et al., 1994: 105.—K.K.P. Lim, 1994b: 331.—H.T.W. Tan et al., 2007: 119.—K.K.P. Lim et al., 2008: 176, 266 ( Singapore Straits).—P.K.A. Ng, 2009: 25.—T.H. Ng & K.K.P. Lim, 2010: 119.—H.T.W. Tan et al., 2010: 158.—L.M. Chou, 2011: 77.—M.A.H. Chua, 2011: 280 (Semakau Landfill [PS]).—P.K.L. Ng et al., 2011: 452.—M.F.C. Ng, 2012: 146.—Y.K. Tan, 2015: 212–213 (“Selat Pandan” [= Pandan Strait]).—W. Wong, 2017: 86.—TTWG, 2021: 98.

“Green turtle”—Zheng & J. Tan, 2017 (Changi Beach).—Van Miriah, 2002: Local.—Thiagarajan, 2020f (“Seringat-Kias…Lazarus Island” [= Pulau Sekijang Pelepah]).— Kow, 2022b (Lazarus Island).

“Leatherback turtles”—K. Lee, 2003: 39.

Remarks. The first report of C. mydas from Singapore is likely erroneous. Crawfurd (1856), who referred to it as the “esculent turtle”, noted that it was very abundant around Singapore, its offshore islands, and markets. Crawfurd (1856) was in all likelihood referring to E. imbricata as this species is more common, it is the only turtle known to nest in Singapore (see account below), and was commonly sold in markets (Raffles 1822). Ridley also heeded that C. mydas was not available in markets in Singapore where turtles were commonly sold and eaten (Shelford 1916). Upon that, the first report of C. mydas from Singapore belongs to Ģnther (1864) who examined two specimens from Cantor’s collection. However, no mention of Singapore is made in Cantor’s account (1847a). Neither do subsequent authors reference Cantor’s specimens. In total, there have only been eight subsequent reported observations of C. mydas in Singapore: one individual found by Flower in 1898 (1899b); one captured in 1914 ( Kobayashi 1920); several individuals seen around Pulau Semakau in 2009 ( Fig. 8B ), including one trapped in a drift net in August 2011 ( Chua 2011); a carcass of one individual observed floating at Selat Pandan on 9 June 2015 that had an obvious laceration on its plastron from a boat propeller (Tan 2015); a similar incident of one struck by a boat propeller that was found dead at Changi Beach on 2 January 2017 (Zheng & Tan 2017), three individuals seen at Seringat-Kias lagoon (Thiagarajan 2020f), and; an injured individual which was rescued off of Lazarus Island ( Kow 2022b). Between Kobayashi (1920) and Chua (2011), C. mydas went unreported for 95 years ( Table 2 ). The leatherback turtles referred to by Lee (2003) most likely represent C. mydas as leatherback turtles do not reside in Singapore’s waters and do not graze on seagrass. In addition, there are two skulls at LKCNHM from 14 May 2015 and 12 December 2015. There are no accounts of C. mydas nesting in Singapore, but it is expected that this species frequents Singapore to forage (TTWG 2021). If there is a seasonal foraging period in which C. mydas forages in Singapore, it should encompass the nesting period in Peninsular Malaysia which runs from February to September ( Abd Mutalib et al. 2014). Albeit scant, the five records here span May to December. Cantor (1847a) said that C. mydas is caught in fishing stakes year-round in Malaysia. As Singapore forms part of its foraging habitat, C. mydas is considered native to Singapore.

Occurrence. Native, Singapore is part of foraging habitat. Rare.

Singapore conservation status. Critically Endangered.

Conservation priority. Highest.

IUCN conservation status. Endangered [2004].

LKCNHM & NHMUK Museum specimens. Changi Beach: ZRC.2.7099 (14-May-2015); Semakau Landfill : ZRC.2.7124 (12-Dec-2015) .

Additional Singapore museum specimens. No specimens.

Singapore localities. Changi Beach—Lazarus Island—Pandan Strait—Pulau Semakau—Pulau Sekijang Pelepah— Singapore Straits.

Genus Eretmochelys Fitzinger, 1843 (1 species)

Chelonia (Eretmochelys) Fitzinger, 1843: 30 (type species: Testudo imbricta Linnaeus, 1766 , by original designation; gender feminine).

Figures

FIGURE 8. A) Caretta caretta, B) Chelonia mydas, C) Eretmochelys imbricata, D) Lepidochelys olivacea, E) Dermochelys coriacea, F) Dermochelys coriacea, G) Trachemys scripta, and H) Batagur borneoensis. Photographs by: Halvard Aas Midtun [A], Marcus A.H. Chua [B], Karenne Tun [C], Ashesh Rathor [D], Tan Heok Hui [E], Alastair Rae [F], Holly Siow [G], and Kelvin K.P. Lim [H].