Bioacoustics of Polypedates leucomystax

Remarks. – The Polypedates leucomystax complex is an incompletely understood species group with many distinct forms from various regions masquerading under a single name ( Inger et al., 1999 ; Narins, et al., 1998; Orlov et al., 2001 ; Trepanier et al., 1999 ; Zhao & Adler 1993) if not more. Seven adult males (LSUHC 7759–65; SVL 52–57 mm ) from Pramaoy and an adult female (LSUHC 7817; SVL 79 mm ) from Che Teal Chrum match the description of Polypedates leucomystax leucomystax in Taylor (1962) and four specimens from the northeastern Cardamoms ( Grismer et al., 2007a ; LSUHC 7347–48, 7354–55) in that the skin of the head is fused to the frontoparietal and nasal bones; vocal sac present in males; interorbital space wider than upper eyelid; tympanum distinct; fingers with small (nearly absent in our sample) webbing; toes at least 2/3 webbed; digital discs smaller than tympanum; tibiotarsal articulation reaching from eye to end of snout; vomerine teeth present; and an hourglassshaped, dark marking on head and occiput reaching shoulders (only in LSUHC 7760–62, 7764–65; pattern obscured in LSUHC 7759, 7763). LSUHC 7817 from Che Teal Chrum has four, dark, dorsal stripes instead of an hourglass marking, thus matching the description of P. l. sexvirgatus ( Taylor, 1962 ). Similar variation was reported in populations of this complex from Phnom Aural ( Grismer et al., 2007a ). Individuals of these two populations were collected at night while sitting on the leaves of low bushes next to roadside puddles in anthropogenically modified habitats. Many others were heard calling from nearby vegetation. LSUHC 7847 from Camp 1 (adult male, SVL 49 mm ) matches Taylor’s (1962) description except that the dorsum has dark mottling and the flanks have dark stippling. This specimen was collected deep within undisturbed forest while sitting in vegetation along a small stream. LSUHC 7899 from Camp 2 is a large adult female (SVL 99 m ) generally matching Taylor’s (1962) description except that the dorsum is cream coloured with a few isolated dark spots. This specimen was collected while sitting 1.5 m above a fastflowing, rocky stream coursing through secondary forest. This species complex has been reported from the central Cardamoms by Ohler et al. (2002) and from the northeastern Cardamoms by Grismer et al. (2007a) , Ohler et al. (2002) , Stuart & Emmett (2006), and Swan & Daltry (2002).

Remarks. Much needed research is required to verify the identity of P. leucomystax in Singapore . Polypedates leucomystax represents a problematic species complex harbouring cryptic species that occur sympatrically ( Kuraishi et al. 2012 ). Narins et al. (1998) identified two morphs in Peninsular Malaysia that differed in morphology, allozyme attributes, and bioacoustics. Their “Morph B” was synonymous with the “Malay Clade” of Kuraishi et al. (2013), which was later delineated as P. discantus (Rujirawan et al. 2013) which ranges from Thailand to southern Peninsular Malaysia (Rujirawan et al. 2013). Sheridan et al. (2010) detected two types of calls in P. leucomystax from Singapore , but both were considered to be from the same species . Cantor (1847c) first reported P. leucomystax from Singapore based on a specimen collected in 1845. Flower (1896) found P. leucomystax to be very common in Singapore , as it continues to be today ( Baker & Lim 2012 ), however no new observations were reported for 57 years ( Table 2 ) between Stejneger (1907) and Berry (1964) . Outside of mangroves, P. leucomystax can be found in any habitat throughout Singapore , including urban areas ( Baker & Lim 2012 ). Occurrence. Ubiquitous. Common.