Detailed Guide to the Identification Methods for the Seven Species of Box Turtles

Currently, farming box turtles is one of the hotspots in turtle breeding. There are seven extant species of box turtles. Apart from the Malayan box turtle (Cuora amboinensis), which is a common species, the other six are rarely seen. To help farmers select breeding stock correctly, the identification methods for the seven species of box turtles are introduced below:

1. How box turtles differ from other turtle species

Box turtles are a specialized group among turtles. Their plastron is connected in the middle by a ligament, like a hinge, and is movable. After death, the ligament breaks, and the plastron splits into two parts, so people commonly call box turtles "broken-plate turtles." In life, they can open or close it according to their own needs. If they encounter enemies, they immediately retract the head, tail, and limbs into the shell, the plastron and carapace meet, and the shell closes, forming a box-like structure. If invaded by a snake, the turtle closes its shell and traps the snake until the snake dies, then eats the snake. Therefore, people also call box turtles "snake-subduing turtles" and "snake-pinching turtles." Box turtles have four major characteristics that distinguish them from other turtle species:

First, the carapace and plastron are connected by a ligament (other turtles are connected by bony seams). There are no axillary scutes and no inguinal scutes.

Second, the front half and rear half of the plastron are connected by a ligament (other turtles are connected by bony seams).

Third, the short lateral edge of the vertebral scutes faces backward, and there are 2 anal scutes. Fourth, they are found only in Asia. The above four major characteristics are conditions that box turtles must meet, and none can be missing. If any one condition is missing, it will be another type of turtle.

2. Identification of the seven species of box turtles

The seven species of box turtles are the Malayan box turtle (Cuora amboinensis), the Chinese three-striped box turtle (Cuora trifasciata), Zhou's box turtle (Cuora zhoui), Pan's box turtle (Cuora pani), the golden-headed box turtle (Cuora aurocapitata), the Baise box turtle (Cuora mccordi), and the Yunnan box turtle (Cuora yunnanensis). They all have their own special characteristics. If the differences among species were explained from the perspective of animal taxonomy, it would inevitably involve descriptions of bones, bony plates, the number of scutes, and so on. That would not only be rather complex, but also unsuitable for farmers. Here is a method of identification based on differences in the color and markings of the carapace and plastron of box turtles.

2.1 Carapace shape

Box turtles are aquatic turtles that live in freshwater areas. Because they live in water for a long time, the center of their carapace is slightly flat, and the carapace is elongated oval. However, the Malayan box turtle (Cuora amboinensis) is the exception: the center of its carapace is more raised than in the other 6 species of box turtles, and the carapace resembles a round loaf of bread.

2.2 Carapace color and pattern

Among the seven species of box turtles, the Chinese three-striped box turtle (Cuora trifasciata) has the most distinctive carapace. Its carapace is pale brownish red or orange-red, with three longitudinal stripes in the center. These three longitudinal stripes are an important distinguishing feature that sets it apart from the other six species. The golden-headed box turtle (Cuora aurocapitata) and Pan's box turtle (Cuora pani) have fairly similar carapace colors, being dark reddish brown or dark brown, without any markings. The Malayan box turtle (Cuora amboinensis), Zhou's box turtle (Cuora zhoui), and the Baise box turtle (Cuora mccordi) have black, dark brown, or brown carapaces, without any markings. The Yunnan box turtle (Cuora yunnanensis) has a brownish gray carapace, also without markings.

2.3 Plastron color and markings

The plastrons of the seven species of box turtles are either a single black or pale yellow color without any markings, or have markings of different colors and shapes mixed mainly with black or yellow. These characteristics are one of the important signs for identifying the seven species of box turtles.

2.3.1 Plastron entirely pale yellow

The Yunnan box turtle (Cuora yunnanensis) is the only one of the seven species of box turtles whose plastron is pale yellow. If the turtle's plastron is not only pale yellow but also has round black spots of varying sizes on each scute, then it is the Malayan box turtle (Cuora amboinensis). If the turtle's plastron is mainly pale yellow and the seams connecting each scute form wide black stripes, then it is Pan's box turtle (Cuora pani). If the turtle's plastron is mainly pale yellow and each scute has black stripes of varying thickness shaped like plum blossoms, and if its head is golden yellow, then it is certainly the golden-headed box turtle (Cuora aurocapitata).

2.3.2 Plastron entirely black

If the plastron is completely black without any colored markings, then it is the Chinese three-striped box turtle (Cuora trifasciata); if the plastron is mainly black with pale yellow triangular markings in the center of the plastron, then it is Zhou's box turtle (Cuora zhoui). If the plastron is black with pale yellow markings along the front edge and around the plastron, then it is the Baise box turtle (Cuora mccordi).

When identifying box turtles, the above characteristics should be used in combination so that box turtles can be recognized accurately and breeding stock can be selected correctly.