Diagnostic Features

• Carapace oval shaped in dorsal view, its width approximately 90% of its length.
• Head relatively short and blunt - approximately 20% of Carapace length
• Tomium of lower jaw has sharply serrated rim corresponding to strong ridges on the inner surface of the upper tomium.
• The carapacial scutes are thin, smooth and flexible when removed.
• Five central scutes, low keeled in juveniles, but lacking a median keel in adults and sub adults.
• Each flipper has one visible claw.
• Colour: On the upper side, the colour can vary from pale to dark and from plain colour to vivid combinations of yellow, brown and green. These may form radiated stripes or a blotch effect. The Pacific populations (namely Chelonia mydas japonica) are more melanistic than the Atlantic ones (Chelonia mydas mydas) and easily confused with the Black turtle (Chelonia agassizii). Recent genetic studies by Bowen and Karl in Lutz & Musick suggest that C.agassizii is not a separate species to C.Mydas. The underside in Atlantic forms is plain white through to a yellowish white. Pacific populations have a dark grey, blue or blue/green underside.
Juveniles have a yellow border to scales on the head and upper side of flippers. Hatchlings are dark brown/black. The rear edges of the flippers and the rim of the carapace is white. Underneath they are white.

Green sea turtle carapace illustration: M. Demma © ICRAM

Figures for females were assumed to be obtained during nesting.
SCL = Straight Carapace Length
CCL = Curved Carapace Length
Min. and Max. recorded sizes for adults:
Min: (at maturity) 78 cm (SCL) Solomons.
Max: 139.5 cm (CCL) Ascension Island.
n.b. CCL gives a figure which is approximately 3-4 cms longer than SCL.
World variation: (mean) figures, unless stated, are for mature females.
Surinam 112cm Pritchard (1979)
Ascension Island 108cm Carr and Hirth (1962)
Guyana 107cm Pritchard (1979)
Aldabra 103cm Frazier (1971)
Florida 101cm Ehrhart (1979)
Costa Rica 100cm Carr and Hirth (1962)
Yemmen 96cm Hirth (1971)
Sarawak 95cm Hendrickson (1958)
Turkey(Cukurova) 90cm Geldiay & Koray (1982)
Turke (Mersin) 95cm Baran,Durmas & Atatur (1988)
N.Cyprus 92cm Broderick & Godley (1992-95)

Yemen 71-104 cm (FAO) for males,
which are generally smaller

Most figures taken from a paper by LM Ehrhart (1984).

Overall body mass in Kg:
This varies considerably according to size, age and native population. In general the mass of a mature turtle ranges from 90 Kg to over 180 Kg
Australia 186 kg FAO
Solomons 89.9 kg FAO
Surinam 235 kg FAO

West Indies 395 kg FAO Claim from the 1960's !
(CCL - 150 cms)
West Indies figures are unconfirmed and unsexed