(3) P. australis.—199-220 ventrals; 57-70 subcaudals; frontal shield once and two-thirds to twice as long as broad.

Colour pale brown on the back, yellowish on the belly.

(4) P. darwiniensis.—Frontal as broad as long; 212 ventrals; 54-64 subcaudals.

Colour reddish-brown; head pale brown; belly yellowish-white.

(5) P. papuanus.—Scales in 19-21 rows (26 or 27 on the neck); 221-224 ventrals; 49-55 subcaudals.

Colour uniform black; chin white.

(6) P. scutellatus.—Subcaudal shields in 2 rows; scales on the body in 23 rows (25-30 on the neck); 230-233 ventrals; 61-78 subcaudals.

Colour pale brown or dark brown; snout and cheeks pale brown or yellowish; belly yellow.

(7) P. microlepidotus.—30-36 scales across the neck, 23 across the middle of the body; 232-237 ventrals; 61-66 pairs of subcaudals.

Colour dark brown on the back, yellowish-grey on the belly; head sometimes blackish.