Colubridae, Oppel, 1811

Weinell, Jeffrey L., Hooper, Errol, Leviton, Alan E. & Brown, Rafe M., 2019, Illustrated Key to the Snakes of the Philippines, Proceedings of the California Academy of Sciences 66 (1), pp. 1-49 : 12

Colubridae

Key to Philippine subfamilies.

1a. Temporal scales absent; parietal scales in contact with supralabial scales ( Fig. 12A )................................................................... Calamariinae (p. 18)

1b. Temporal scales present; parietal scales not in contact with supralabial scales ( Fig. 12B )... 2

2a. Supralabial scales either do not border eye, or supralabial scales 4–6 border eye; if supralabial scales 4–6 border eye, then dorsal body scales reduce from 19→17 or from 17→15 longitudinal rows posteriorly, and lateral body scales (except possibly first row) keeled ( Fig. 3B )...................................................................... Natricinae (p. 19)

2b. One or more supralabial scales border eye; if supralabial scales 4–6 border eye and dorsal body scales reduce from 19→17 or 17→15 longitudinal rows posteriorly, then lateral body scales are smooth ( Fig. 3C )................................................ 3

3a. Lateral body scales in oblique rows ( Fig. 15A ); dorsal body scales reduce from 17→13, 15→13, 15→11, or 13→11 longitudinal scale rows posteriorly; third supralabial scale does not border eye................................................... Ahaetulliinae (p. 17)

3b. One of the following combinations of characters true: (1) lateral body scales in horizontal, not oblique rows ( Fig. 13B ), and dorsal body scales in 13 longitudinal rows at midbody; (2) lateral body scales in oblique rows ( Fig. 15A ) and dorsal body scales in 15–17 longitudinal rows at midbody, not reducing to fewer than 15 rows before vent; (3) lateral body scales in oblique or horizontal rows (compare Fig. 15A, B ), and dorsal body scales in 19–23 longitudinal rows at midbody.................................................................... 4

4a. Dorsal body scales in 17 smooth longitudinal rows throughout length of body; number of ventral body scales 144–185; subcaudal scales arranged in 89–145 pairs; numerous small teeth, 30–50, on each of maxillary and dentary bones.................... Sibynophiinae (p. 19)

4b. Dorsal body scales in 15–23 smooth or keeled longitudinal rows at midbody; if dorsal body scales in 17 smooth longitudinal rows throughout length of body, then subcaudal scales arranged in <80 or> 190 pairs; fewer than 30 teeth on each of maxillary and dentary bones..................................................................... Colubrinae (p. 18)

Figures

FIGURE 12. Lateral view of head of (A) Calamaria gervaisii (KU 322329), (B) Lycodon muelleri (KU 327575). Temporal scales (green), supralabial scales (purplish-gray), parietal scale (blue).

FIGURE 3. Dorsal body scales: (A) spinose (Acrochordus granulatus; KU 302951), (B) keeled (Opisthotropis typica; KU 327424), (C) smooth (Oligodon maculatus; KU 321699).

FIGURE 15. Lateral body scales of (A) Dendrelaphis marenae (KU 314131): oblique rows, (B) Oligodon maculatus (KU 321699): horizontal rows.

FIGURE 13. Lateral view of head of (A) Psammodynastes pulverulentus (KU 329688), (B) Cyclocorus lineatus alcalai (KU 324539). Nasal scale (green) undivided (A) or divided (B).