Wolfsnakes, genus Lycodon Fitzinger, 1826, are known to prey upon rodents and frogs (Fritts, 1993), and they may even endanger the survival of bird species (Khamcha and Gale, 2020). However, their biggest impact as a predator is most likely on the broad variety of lizards they consume, including house geckos, skinks, and agamids (Fritts, 1993; Pauwels et al., 2005; Vogel et al., 2009; Zhang and Wang, 2014). Lycodon aulicus (Linnaeus, 1758) in particular is known to feed on common house geckos (Daniel, 2002; Jackson and Fritts, 2004) and, consequently, it may frequently be seen in and around residential buildings where these prey species are most commonly encountered (Shroff, 2016). Behavioural information about L. aulicus is rather scarce, although a few studies on some populations and its distribution have been carried out (Ganesh and Vogel, 2018; Deshmuk et al., 2020; Ganesh et al., 2020). The species is chiefy nocturnal and known to be partly arboreal, sometimes utilizing tall trees (Harrington et al., 2018), but is most frequently observed in crevices or depressions, under objects, or moving near human settlements. These are generally shy and alert snakes, but they may exhibit more aggressive behaviour than other wolfsnakes (Harris et al., 2010). Several specimens encountered on the campus of the College of Natural Resources, Punakha, Bhutan, coiled up when provoked and tried to escape. Repeated attempts to bite while being handled have been observed by the frst author. Hemidactylus frenatus Duméril & Bibron, 1836 is a common house gecko that occurs throughout most of tropical Asia eastwards into the western Pacifc, with introduced populations in parts of Africa, the Americas, and many islands of the Indian and Pacifc Oceans (Kraus, 2009). These moderate-sized geckos (maximum snout-to-vent length 65 mm) were identifed using identifcation keys in Smith (1943), Vyas (2005), Giri and Bauer (2008), and Lajmi et al. (2016). In this article, we report the observation of Lycodon aulicus preying upon Hemidactylus frenatus and provide a description of how the attack happened in a sequence of photos with textual commentary. The second author’s neighbour sought his help to remove a snake found in her ceiling on 11 November 2018 at Burichhu, Tsirang District, Bhutan (27.0823°N, 90.0762°E, elevation 470 m). The atmospheric tempera- ture at the time was ca. 14°C while the room tempera- ture was slightly higher at ca. 17°C (NCHM, 2017). We suspect that the usually nocturnal snake became active during the warm morning and took the opportunity en- ter the warmer, two-storied traditional Bhutanese house to hunt. Both prey availability and warmth could have attracted the snake, which scaled the building’s walls, as also reported by Ganesh et al. (2020). A common wolfsnake (total length ca. 800 mm) was found on one of the ceiling joists, holding a common house gecko in its jaws (Fig. 1). The series of behaviours by the snake associated with predation on the gecko during the fol- lowing several minutes were observed and are reported in detail as follows: The snake was frst encountered strongly biting the central body of the gecko with two coils compressing the anterior part of the body, likely making it diffcult for the gecko to infate its lungs to breathe (Fig. 1). Upon detection of our presence the snake released the gecko (presumably to allow it to react to the disturbance), which dropped to the foor of the home. Unlike normal house gecko behaviour, the seriously Herpetology Notes, volume 14: 749-753 (2021) (published online on 10 May 2021) Predation by the wolfsnake Lycodon aulicus (Linnaeus, 1758) on the house gecko Hemidactylus frenatus Duméril & Bibron, 1836 in Tsirang District, Kingdom of Bhutan Jigme Tshelthrim Wangyal 1,* , Pema Khandu 2 , and Gyeltshen Gyeltshen 3 1 University of New England, Armidale, New South Wales 2350, Australia. Present address: Jigme Khesar Strict Nature Reserve, Haa 15001, Bhutan. 2 Wangbama Central School, Genekha, Thimphu, Bhutan. 3 Mendrelgang Primary School, Tsirang, Bhutan. * Corresponding author. E-mail: jigmewangyal@gmail.com © 2021 by Herpetology Notes. Open Access by CC BY-NC-ND 4.0.