Varanus dumerilii Schlegel, 1839

Figueroa, Alex, Low, Martyn E. Y. & Lim, Kelvin K. P., 2023, Singapore’s herpetofauna: updated and annotated checklist, history, conservation, and distribution, Zootaxa 5287 (1), pp. 1-378 : 127-128

Varanus dumerilii Schlegel, 1839 — Native.

Monitor Dumerilii Schlegel, 1839: 78 . Holotype: RMNH.RENA.3168, by original designation. Type locality: “[e]rstere kommt von Borneo”; later designated as “Banjermasin, southern Kalimantan ”, Indonesia by Bennet (2004: 172).

Dumeril’s Monitor

( Figure 15D )

Singapore records.

Varanus dumerili — de Fejérváry, 1935: 129.

Varanus dumerili — L.M. Chou et al., 1980: 71.—K.K.P. Lim & F.L.K. Lim, 1992: 149.—J.K.Y. Low et al., 1994: 158.—N. Baker & K.P. Lim, 2012: 160.

Varanus dumerilii —Bennett, 1995: 36.—Bennet & B.L. Lim, 1995: 113.— Cox et al., 1998: 107.—K.P. Lim & F.L.K. Lim, 2002: 149.—N. Baker & K.P. Lim, 2008: 160.— Cota et al., 2008: 152.—Yong et al., 2008: 21–22 (Nee Soon Swamp Forest).—T.M. Leong, K.K.P. Lim & N. Baker, 2009: 492.— Das, 2010: 255.—H.T.W. Tan et al., 2010: 229.—P.K.L. Ng et al., 2011: 382.— Janssen & Sy, 2022: 137, 172.—E.Y.L Lui, 2022: 1 (Upper Seletar).

Empagusia dumerilii —Pettit et al., 2021: 113.

Remarks. At the time that Yong et al. (2008) filmed an adult V. dumerilii foraging at 2245 hrs at NSSF on 18 January 2008, V. dumerilii was only known from one historic record. That record was of a skull deposited at HNHM that was collected by Xantus ( de Fejérváry 1935). Since no records were reported after, V. dumerilii was considered extirpated from Singapore (Bennett 1995). Thus, Yong et al. (2008) record constitutes a rediscovery of V. dumerilii in Singapore after 73 years ( Table 2 ). Here, we present five additional records. Two records are from museum specimens, SAMA R15537 and ZMH R07222, both which contain no useful data. The other three records are of a juvenile photographed on 5 August 2012 (A. Ibrahim pers. comm.), an adult photographed on 26 December 2015 (I.S. Law pers. comm.; Fig. 15D ), both at NSSF, and an adult filmed on a road at Upper Seletar on 14 October 2022 ( Lui 2022). These latter records confirm the presence of V. dumerilii in Singapore and offers that a viable population exists. Varanus dumerilii is an uncommon species that seems to prefer mangroves or riparian areas in mature forests and feeds predominately on crabs ( Grismer 2011b). Targeted surveys are required to establish the population status of V. dumerilii in Singapore and determine whether the population is self-sustaining.

Occurrence. Known from three museum specimens, and three records from NSSF after 2008. Rare.

Singapore conservation status. Critically Endangered.

Conservation priority. Highest.

IUCN conservation status. Data Deficient [2021].

LKCNHM & NHMUK Museum specimens. No specimens.

Additional Singapore museum specimens. Singapore (no locality): SAMA, ZMH.

Singapore localities. Nee Soon Swamp Forest—Upper Seletar.

Figures

FIGURE 15. A) Lipinia vittigera, B) Subdoluseps bowringii, C) Tytthoscincus temasekensis, D) Varanus dumerilii, E) Varanus nebulosus, F) Varanus salvator, G) Acrochordus granulatus, and H) Ahaetulla fasciolata. Photographs by:Alex Figueroa [A–B, F], Shivaram Rasu [C], Law Ing Sind [D, G], Thio Hui Bing [E], and Lena S.Y. Chow [H].