1. Dermatochelys coriacea (Blainville) = Dermochelys coriacea (Vandelli, 1761)
2. Caretta imbricata (Gray) = Eretmochelys imbricata (Linnaeus, 1766)
3. Hydromeda tectifera (Wagler) = Hydromedusa tectifera Cope, 1869
4. Chelys fimbriata (Duméril) = Chelus fimbriata (Schneider, 1783)
5. Testudo geometrica (Linné) = Psammobates geometricus (Linnaeus, 1758)
6. Testudo elephantina (Duméril) = Dipsochelys dussumieri Gray, 1831
7. Chelydra serpentina (Schweigger) = Chelydra serpentina (Linnaeus, 1758)
English:
1: Leatherback Turtle
2: Hawksbill Turtle
3: Argentine Snake-necked Turtle
4: Mata mata
5: Geometric Tortoise
6: Galápagos Tortoise
7: Common Snapping Turtle
Date 1904
Source Kunstformen der Natur (1904), plate 89: Chelonia (see here, here and here)
Author Ernst Haeckel (1834–1919)
Source: https://commons.wikimedia.org/wiki/File:Haeckel_Chelonia.jpg

1. Dermatochelys coriacea = leatherback sea turtle (Dermochelys coriacea)
The leatherback sea turtle (Dermochelys coriacea), sometimes called the lute turtle or leathery turtle or simply the luth, is the largest of all living turtles and is the fourth-heaviest modern reptile behind three crocodilians.

2. Caretta imbricata = hawksbill sea turtle (Eretmochelys imbricata)
The hawksbill sea turtle (Eretmochelys imbricata) is a critically endangered sea turtle belonging to the family Cheloniidae. It is the only extant species in the genus Eretmochelys. The species has a worldwide distribution, with Atlantic and Indo-Pacific subspecies.

3. Hydromeda tectifera = Argentine snake-necked turtle (Hydromedusa tectifera)
The Argentine snake-necked turtle or South American snake-necked turtle (Hydromedusa tectifera) is a species of turtle, known for the long neck which gave it its name. Despite appearances, the Argentine snake-necked turtle is probably more closely related to the Mata mata (Chelus fimbriatus) than to the Australian snake-necked turtles in the genus Chelodina. It is found in northern Argentina, Uruguay, Paraguay, and southern Brazil.

4. Chelys fimbriata = matamata turtle (Chelus fimbriata)
The mata mata, mata-mata, or matamata (Chelus fimbriata) is a freshwater turtle found in South America, primarily in the Amazon and Orinoco basins. It is the only extant species in the genus Chelus.

5. Testudo geometrica = geometric tortoise (Psammobates geometricus)
The geometric tortoise (Psammobates geometricus) is a critically endangered species of tortoise and one of three members of the genus, Psammobates. It is found in a very small section in the South-Western Cape of South Africa.

6. Testudo elephantina = Aldabra giant tortoise (Aldabrachelys gigantea)
The Aldabra giant tortoise (Aldabrachelys gigantea), from the islands of the Aldabra Atoll in the Seychelles, is one of the largest tortoises in the world.

7. Chelydra serpentina = common snapping turtle (Chelydra serpentina)
The common snapping turtle (Chelydra serpentina) is a large freshwater turtle of the family Chelydridae. Its natural range extends from southeastern Canada, southwest to the edge of the Rocky Mountains, as far east as Nova Scotia and Florida.