LEVITON, BROWN, & SILER: PHILIPPINE VENOMOUS SNAKES 
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ABC 
Figure 19. Ventral scales in hydrophiine sea snakes (adapted from Smith, 1926, pis. I and II). (A) undivided and 
indistinguishable from adjacent scales (Hydrophis [Lapemis] curtus); (B) usually distinguishable from adjacent 
scales {Hydrophis cyanocinctus); (C) divided by a longitudinal groove {Hydrophis gracilis) 
frontal and parietal scales 
not fragmented 
Figures 20A-C. Scales on dorsum of head: (A) scales unfragmented {Hydrophis [Enhydrina] schistosus) and 
(B) {Hydrophis cyanocinctus)-, (C) frontal and parietal head scales fragmented {Hydrophis [Acalyptophis] peronii). 
Frontal and parietal 
scales fragmented 
Figures 21A-B. Mental scale: (A) normal, neither elongate nor partially hidden from view in mental symphysis 
{Hydrophis)-, (B) elongate mental scale partially hidden in mental symphysis when mouth is 
closed {Hydrophis [Enhydrina) schistosus) 
Figure 22. Hydrophis [Enhydrina) schistosus. Photo courtesy of Harold Voris. 
31a. 26-36 dark middorsal blotches or bands on body; anteriorly interspaees between dorsal dark 
body bands more than 2 seale rows wide; 4-6 dark bands on tail; 37-45 seale rows around 
neek; ventral seales 258-306; 9-12 maxillary teeth behind front fangs. . . Hydrophis lamberti 
