Key to identifying Heosemys species

The genus Heosemys consists of four species

Scientific nameFirst descriptionCommon name
Heosemys annandaliiBoulenger 1903Yellow-headed temple turtle
Heosemys depressaAnderson 1875Arakan forest turtle
Heosemys grandisGray 1860 Giant Asian pond turtle (or: Orange-headed temple turtle)
Heosemys spinosaGray 1831Spiny hill turtle (or: Cogwheel turtle)

Determination table

Heosemys grandis plastron
Heosemys spinosa plastron

Section A

A1 Does the plastron have a plastral hinge?

Yes → Not a Heosemys
No plastral hinge (although the plastron may be slightly movable) → A2

A2 Is the seam between the anal and femoral scutes straight across or does it angle slightly forward?

Yes → A3
No, it curves far forwards → Not a Heosemys

A3 Is the straight carapace length more than 30 cm?

Yes → D2
No → A4

A4 Is the carapace serrated only posteriorly?

Yes → C1
No → B1

Section B

B1 Does the turtle have spines around it's shell?

Yes → Heosemys spinosa
No → B2

B2 Is the carapace more round than elongated?

Yes → Heosemys spinosa
No → B3

B3 Does the turtle have red or pale blotches on the head?

Yes → Heosemys spinosa
No → C1

Section C

C1 Do the eyes have brown irises?

Yes → Heosemys depressa
No → C2

C2 Does the plastron have an irregular pattern of black blotches?

Yes → Heosemys depressa
No → D1

Section D

D1 Does the turtle have coloured stripes on the head?

Yes → Heosemys annandalii
No → D2

D2 Does the turtle have orange speckles on it's head?

Yes → Heosemys grandis
No → D3

D3 Does the carapace have a flattened keel?

Yes → Heosemys annandalii
No, it has a well-pronounced keel → D4

D4 Is the plastron yellow/orange with dark radiating lines?

Yes → D5
No, the plastron has regular black blotches on each scute, but no radiating lines → Heosemys annandalii
No, the plastron is (mostly) black → Heosemys annandalii
No, the plastron is yellow/orange → D5

D5 Is the interfemoral seam longer than the interpectoral seam?

Yes → Heosemys grandis
No → Heosemys spinosa

• sources: Ernst & Barbour (1989), P.P. van Dijk (forum topic, 2001)
Post your comments about this page