Varanus cumingi Martin, 1838

Figures 4–14

Synonymy. No synonyms of this Philippine monitor species are known (Böhme 2003).

Diagnosis. The diagnosis following the arguments by Gaulke (1992a) and Koch et al. (2007) was modified only with respect to scalation features due to the enlarged data set for this study. As a conspicuous member of the V. salvator complex, V. c u m i n g i can be identified by two main features: (1) the intensive yellow colour pattern of head and body in combination with the black background colour; (2) possessing enlarged occipital scales around the pineal organ (character P = 46–57, mean = 49.89); (3) enlarged dorsal scales (characters X = 21–33, mean = 27.79; Y = 86–103, mean = 92.63; and XY = 114–136, mean = 120.42); and (4) low scale counts around the tail at one third of the tail length (character R = 42–55, mean = 47.57). Additional characteristics of the colour pattern of V. cumingi are (5) more-or-less distinct longitudinal black ocelli on the ventral side of the tail; (6) a pronounced black streak extending from the eye to the upper margin of the tympanum; (7) usually a unicoloured yellow chin without dark bars or crossbands; and (8) eight to fifteen dark lateral bars or crossbands on the belly.

For details about scalation features and colour pattern of the remaining Philippine members of the V. salvator complex we refer to Tables 3 and 5.

Intraspecific variation. The main morphometrics and scalation features of V. cumingi are provided in Tables 3 and 5. Our investigations confirm striking variation in colour patterns of V. cumingi (see also Gaulke 1991a: 161). In general, specimens from Mindanao, the type locality, show a brighter and less distinct colour pattern on the dorsal side compared with the populations from other islands within the distribution range (Tab.

5). On this basis, the Mindanao population has been referred to as the bright morphotype of the taxon cumingi by Gaulke (1992a) and Koch et al. (2007). Monitors from Mindanao exhibit an obvious tendency towards yellow crossbands on the dorsal side rather than transverse rows of spots or ocelli. In addition, some specimens exhibit a more-or-less continuous yellow medio-dorsal stripe, which extends from the neck towards the base of the tail (Fig. 4). In other specimens from Mindanao, an augmentation of yellow transverse rows on the dorsal side is recognisable. The ventral colour pattern of the Mindanao population may consist of V-shaped, pointed bars or crossbands on a bright background colour. In contrast, V. cumingi from Samar, Leyte and Bohol, known as the dark morphotype (Gaulke 1992a; Koch et al. 2007), is characterised by a dorsal colour pattern rich in contrast on a black background colour and well defined yellow spots, ocelli or other markings arranged in transverse rows (Fig. 14). Gaulke (1992a) observed that specimens from Bohol showed a whitish rather than yellowish throat. Basilan specimens that have also been assigned to the dark phenotype of V. c u m i n g i by Gaulke (1992a) were not available for detailed analysis. Besides these geographical variations in colour pattern, some kind of ontogenetic change in colour pattern is observable in V. cumingi (see Wicker et al. 1999). Juveniles are much darker. In particular, the head shows salvator -typical dark crossbands on the snout, and distinct transverse rows of small bright spots on the dorsal side. As the juveniles mature, the characteristic yellow cumingi colouration becomes more pronounced with extended bright parts on the head and back. This extraordinary colour change is unique for V. c u m i n g i amongst members of the V. salvator complex.

Due to the geographically correlated differences in colour pattern between allopatric island populations of V. c u m i n g i, we describe the populations from Samar, Leyte, and Bohol as a new subspecies of this remarkable Philippine water monitor species as already claimed by Gaulke (1991a).

Conservation status. Currently, V. cumingi is listed as “least concern” by the IUCN (Sy et al. 2007). Nevertheless, this relatively common Philippine monitor lizard species is suspected decreasing because of overharvesting.