If I am thinking of the same source, that would be Ptyas carinata, not E. carinata. However, I would not be surprised if both species were capable of such a feat.
-----
Current snakes:

0.0.1 Gonyosoma oxycephala - Java locale (green)

1.2 Gonyosoma oxycephala - Jave local (green)

2.2 Gonyosoma janseni - Seleyar locale (all black)

1.2 Gonyosoma janseni - Celebes locale (Black & Tan)