Gekko gecko (Linnaeus, 1758)

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 : 105-106

Gekko gecko (Linnaeus, 1758) — Non-native; Established.

Lacerta Gecko Linnaeus, 1758: 205 . Syntypes (2): UUZM 17 and 35, according to de Lisle et al. (2021: 249); type material previously considered lost, according to Andersson (1900: 13). Type locality: “[h]abitat in Indiis, frequens etiam in domibus”, in error; later designated as “ Java ”, Indonesia by Mertens (1955).

Tokay Gecko

( Figure 12G ; Mandai Resort)

Singapore records:

Gecko [sic] guttatus —F. M̧ller, 1878: 638.

Gecko [sic] verticillatus — Flower, 1896: 867.— Hanitsch, 1898: 19.— Flower, 1899: 631.—Ridley, 1899: 193, 206.— Hanitsch, 1910b: 7.— Boulenger, 1912: 50.— Hanitsch, 1912b: 14.—Sworder, 1925a: 64.— Chasen, 1925: 101.— Chasen & Smedley, 1927: 352.

Gekko gecko —L.M. Chou, 1975: 134.—F.L.K. Lim, 1984: 18.—N. Koh, 1986: 1–2.—K.K.P. Lim & L.M. Chou, 1990: 55.— Anonymous, 1991b: 12 (“fringe of the central water catchment area”).—K.K.P. Lim & F.L.K. Lim, 1992: 115, 150.—L.M. Chou et al., 1994: 105.—K.K.P. Lim, 1994b: 331.—R. Subaraj, 1995: 33, 35.— Manthey & Grossmann, 1997: 231.—Chan-ard et al., 1999: 24.—K.P. Lim & F.L.K. Lim, 2002: 150.—N. Baker & K.P. Lim, 2008: 160.—K.K.P. Lim et al., 2008: 265.— Das, 2010: 218.—L.L. Grismer, 2011b: 458, 462.—Ooi et al., 2011: 163.—N. Baker & K.P. Lim, 2012: 165.—K.K.P. Lim, 2014c: 224 ( Singapore Zoo).—Chan-ard et al., 2015: 73.—R. Subaraj, 2015: 32, 38, 47, 52 (Night Safari; Singapore Zoo).—S. Subaraj, 2015: 6, 7 (Night Safari; Singapore Zoo).— Khew & Yokohari, 2017: 12.— Fauzan et al., 2022: 212.— Janssen & Sy, 2022: 160.

Gekko gekko [sic]—D.S. Johnson, 1964: 25.—D.S. Johnson, 1992: 35.—R. Subaraj et al., 1995: 18 (Pulau Senang).

Gekko gecko gecko — Denzer & Manthey, 1991: 314.

Remarks. M̧ller (1878) first reported G. gecko from Singapore from a specimen at NMB. Flower (1896) incorrectly stated that Blanford (1881) listed Singapore as a locality for specimens he received from Dennys, but Blanford (1881) does not specify any locality in his account. In the Raffles Museum (now LKCNHM) annual report, Hanitsch (1898) listed Singapore, Myanmar, and Bangkok as localities of G. gecko specimens in the collection. The Singapore locality likely refers to the specimen(s) in Blanford (1881), and not newly collected material as Ridley (1899) opines that the Singapore locality “must be very dubious”. However, a few years after, Hanitsch (1910) reported receiving three specimens from three different people, but did not provide any locality data, and Chasen & Smedley (1927) examined one at the Raffles Museum collected by Lister in 1923, also from an unknown locality. The only early locality data for G. gecko comes from ZRC.2.1001 which was collected around Bukit Timah on 14 October 1908. The next reported record after Chasen & Smedley (1927) came 64 years later ( Table 2 ) when one was photographed on the Singapore Zoo grounds ( Anonymous 1991b). Presently, G. gecko is found only within Singapore Zoo and Night Safari, with some heard in the surrounding forest (A. Figueroa pers. obs.). This population is believed to be descendants of escaped captive animals from Singapore Zoo ( Lim 2014c). Given how widespread and prolific G. gecko is throughout its native range, it’s surprising that it has not dispersed outside the Mandai Wildlife Reserve peninsula. However, G. gecko is currently expanding its range with the continued expansion of Mandai Wildlife Reserve. A population of G. gecko also inhabits Pulau Senang (Subaraj et al. 1995), and given that it does not occur on any of the surrounding islands, the Pulau Senang population is likely also introduced. Specimen ZRC.2.6803 was collected in December 2008 from army personnel who say it was found at Nee Soon Firing Range. Clearly, this record requires confirmation.

Boulenger (1912), not Flower (1899) as cited in Grismer (2011), expressed G. gecko’s presence in Singapore is likely due to human introduction, and Sworder (1925a) stated that it is a well-known fact that G. gecko was introduced in Singapore, as it was not known in Peninsular Malaysia, except for in Penang and Province Wellesley (= Seberang Perai) ( Boulenger 1912). Chasen (1925) described G. gecko as not uncommon in Singapore and localised in its distribution being mainly confined to homes in “one of the native quarters”. Chasen (1925) also wrote that an unspecified early account of G. gecko’s introduction into Singapore stated that individuals were brought in from Java around 1898. Given, that G. gecko is presently only found at the parks of Mandai Wildlife Reserve, it is apparently the only introduction of this species to establish a viable population.

Occurrence. Restricted to Singapore Zoo, Night Safari, and a few adjacent areas. Common.

Singapore conservation status. Not Applicable.

Conservation priority. None, non-native species.

IUCN conservation status. Least Concern [2019].

LKCNHM & NHMUK Museum specimens. Singapore (no locality) : ZRC.2.1002 (20-Dec-1909) , ZRC.2.1003 (1923), ZRC.2.1485 (1940); Bukit Timah : ZRC.2.1001 (14-Oct-1908) ; Pulau Senang: ZRC.2.3194 (12- Oct-1969) , ZRC.2.3193 (23-Oct-1969) ; Upper Seletar [ NSSF] : ZRC.2.6803 (Dec-2008) .

Additional Singapore museum specimens. Singapore (no locality): MPM, MVZ.

Singapore localities. Bukit Timah (not specified) *—Mandai Resort—Nee Soon Swamp Forest*—Night Safari— Pulau Senang—Singapore Zoo.

Figures

FIGURE 12. A) Cyrtodactylus majulah, B) Cyrtodactylus pantiensis, C) Cyrtodactylus quadrivirgatus, D) Cyrtodactylus semenanjungensis, E) Gehyra mutilata, F) Gekko browni, G) Gekko gecko, and H) Gekko horsfieldii. Photographs by: Alex Figueroa [A, C, G], Tan Heok Hui [B], Nick Baker [D], and Kelvin K.P. Lim [E–F, H].