Dendrelaphis philippinensis Günther, 1879

Rooijen, Johan Van & Vogel, Gernot, 2012, A revision of the taxonomy of Dendrelaphis caudolineatus (Gray, 1834) (Serpentes: Colubridae), Zootaxa 3272, pp. 1-25 : 17-19

Dendrelaphis philippinensis Günther, 1879

Figs. 12 , 13 .

Description. A species of the Dendrelaphis caudolineatus group, characterized by the combination of 1) a reduced pattern of black longitudinal stripes, 2–6 black longitudinal stripes at midbody; 2) a pale ventrolateral line is absent or faintly present; 3) a postocular stripe is present and extends onto the neck; 4) 162–170 ventrals (males), 161–172 [179] ventrals (females); 5) 94–108 subcaudals; 6) relative tail-length 0.268–0.298 (males), 0.252–0.290 (females); 7) 6–7 temporal scales on each side; 8) 9–11 infralabials on each side; 9) 2–5 scales touching the posterior borders of the parietal scales; 10) maximum total length males 89.0 cm, females 119.5 cm.

Description of holotype. BMNH 1946.1.6.69 (formerly BMNH 1877.10.9.62), adult female from North Mindanao collected by A. Everett ; SVL 76.0 cm; TAIL 30.0 cm; 164 ventral scales; 100 subcaudal scales; anal shield divided; dorsal scales in 13-13-11 rows; 9 supralabials, supralabials 4,5,6 (L) 5,6 (R) touch the eye; 10 (L), 9 (R) infralalabials, infralabials 6 and 7 touch first sublabial; infralabials 1–5 touch first chinshield, infralabials 5,6 touch second chinshield; 2 postoculars; temporal formula 2:2:2/2:2:2; vertebral scales not enlarged; eye-diameter 5.4 mm; eye-nostril distance 5.8 mm; snout-width 6.2 mm; posterior edge of parietal scales touched by 3 scales; head-length 29.5 mm; ground-colour olive-brown; supralabials, chin, throat yellow; venter yellow; black temporal stripe covers more than half of temporal region, extends onto neck where it fades away; 4 black stripes anteriorly (including extensions of temporal stripes), disappear towards middle of body, reappear posteriorly; faint ventrolateral line present; black stripe on underside of tail.

Sexual dimorphism. Females grow larger than males (see description). None of the other examined characters exhibits sexual dimorphism.

Geographic variation. In spite of the large number of geographically isolated populations, D. philippinensis appears to exhibit little inter-population variation in its morphology. However, populations do differ in their coloration. For instance, in the population from Mindanao ( Fig. 12 ), the pattern of longitudinal black stripes is reduced to two narrow stripes that occupy little more than the outer edges of the ventral scales whereas the populations from South Luzon and Catanduanes ( Fig. 13 ) exhibit comparatively pronounced longitudinal stripes. This may be taxonomically significant. On the other hand, differences in the degree to which the pattern of longitudinal stripes is manifest, were also noted within populations.

Distribution. Dendrelaphis philippinensis inhabits the Philippine islands Basilan, Mindanao, Samar, Leyte, Bohol, Cebu, Polillo, Kalotkot, Catanduanes as well as South Luzon (Albay).

Figures

FIGURE 12. Dendrelaphis philippinensis Günther, 1879, adult from Mindanao, holotype (BMNH 1946.1.6.69; TL 106 cm.).

FIGURE 13. Dendrelaphis philippinensis Günther, 1879, adult from Catanduanes (USNM 319029; TL 103.5).