Dasia olivacea Gray, 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 : 119-120

Dasia olivacea Gray, 1839 — Native.

Dasia olivacea Gray, 1839: 331 . Type material: None designated ; type material apparently lost, according to Smith (1935: 277) . Type locality: “Prince of Wales’s Island” (= Penang Island ), Peninsular Malaysia .

Olive Tree Skink

( Figure 14E )

Singapore records.

Lygosoma olivaceum — Flower, 1896: 874 [“Galang” [= Geylang].— Flower, 1899: 649.— Hanitsch, 1899: 12 (Bukit Timah [BTNR]).—Ridley, 1899: 207.— Boulenger, 1912: 91.— Hanitsch, 1912b: 15.— Sworder, 1925a: 68 (Kranji).— Cross, 2020n: 6, 7 (Changi).

Dasia olivacea — Inger & Brown, 1980: 8–9.—K. Lim, 1990a: 10 (Bukit Timah Nature Reserve).—K.K.P. Lim & L.M. Chou, 1990: 55.— Denzer & Manthey, 1991: 316.—K.K.P. Lim & F.L.K. Lim, 1992: 103, 149.—K.K.P. Lim, 1993a: 4 (Nee Soon Swamp Forest).—L.M. Chou et al., 1994: 105.— K.K.P. Lim, 1994b: 220, 231.—R. Subaraj et al., 1995: 4.—P.K.L. Ng et al., 1995: 122.—R.C.H. Teo & Rajathurai, 1997: 386 (Nee Soon East [NSSF]; Nee Soon Range [NSSF]; Taban & Lasia Valleys [BTNR]).— Manthey & Grossmann, 1997: 260.— Cox et al., 1998: 113.—Chan-ard et al., 1999: 26.—K.P. Lim & F.L.K. Lim, 2002: 149.—K.K.P. Lim et al., 2008: 168, 265 (Pulau Ubin).—N. Baker & K.P. Lim, 2008: 84, 160.— Das, 2010: 230.—L.L. Grismer, 2011a: 140.— L.L. Grismer, 2011b: 551, 556.—N. Baker & K.P. Lim, 2012: 84, 160.—N. Baker, 2014e: 297 (Old Upper Thomson Road).—Chan-ard et al., 2015: 113.— Geissler & Kupfer, 2019: 297.—R.C.H. Teo & Thomas, 2019: 158, 180.—N. Baker, 2020a: 13.—K.K.P. Lim, 2020: 2, 5 (Changi).— Janssen & Sy, 2022: 105, 164.— Kurniawan et al., 2022: 110.

Remarks. Together with D. grisea, Figueroa et al. (2020) reviewed all records of D. olivacea from Singapore and added a new record from Springleaf Forest of an individual basking at the top of a coconut tree on 13 June 2018 ( Fig. 14E ). Unlike D. grisea , D. olivacea has been known from Singapore for a long time ever since Flower (1896) examined a specimen Ridley collected from a coconut tree in Geylang. Dasia olivacea is notably rarer than D. grisea , having only been reported nine times. Between publication of the third (Sworder 1925) and fourth records (Lim 1990), 65 years elapsed ( Table 2 ). In addition, there are two specimens deposited at CAS that were collected by Herre in 1937, and two previously unpublished records by Cross (2020n) from Changi in 1945 that were recently published ( Lim 2020). Adding these four records brings the total number of records of D. olivacea in Singapore to 13. Figueroa et al. (2020) perceived that D. olivacea may be less common than D. grisea because it is being outcompeted by D. grisea , or perhaps because D. grisea has become more successful by adapting to using large exotic trees that tend to contain many cavities or exfoliating bark useful for evading predators.

Occurrence. Restricted to CNR and surrounding Nature Parks and forests. Rare.

Singapore conservation status. Critically Endangered.

Conservation priority. Highest.

IUCN conservation status. Least Concern [2021].

LKCNHM & NHMUK Museum specimens. Singapore (no locality) : BMNH 1896.6 .25.21 (no date) , ZRC.2.1599 (27-Feb-1923) ; Bukit Timah Nature Reserve : ZRC.2.2589 (08-Apr-1990) ; Nee Soon Swamp Forest : ZRC.2.4845 (29-Nov-2000) ; Old Upper Thomson Road : ZRC.2.7063 (10-Apr-2014) .

Additional Singapore museum specimens. Bukit Timah Nature Reserve: CAS.

Singapore localities. Bukit Timah Nature Reserve—Changi*—Geylang*—Kranji—Nee Soon Swamp Forest— Old Upper Thomson Road—Pulau Ubin—Springleaf Forest.

Genus Emoia Gray, 1845 (1 species)

Emoia Gray, 1845: 95 (type species: Scincus atrocostatus Lesson, 1830 , by subsequent designation by Stejneger, 1899: 807; gender feminine).

Figures

FIGURE 14. A) Hemiphyllodactylus typus, B) Lepidodactylus lugubris, C) Iguana iguana, D) Dasia grisea, E) Dasia olivacea, F) Emoia atrocostata, G) Eutropis multifasciatus, and H) Eutropis rugifera. Photographs by: Alex Figueroa [A, G], Holly Siow [B], Kelvin K.P. Lim [C], Law Ing Sind [D, H], Chloe Tan [E], and Nick Baker [F].