Oligodon purpurascens (Schlegel, 1837)

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 : 169-171

Oligodon purpurascens (Schlegel, 1837) — Native; Indeterminate.

Xenodon purpurascens Schlegel, 1837: 90–91 , 139, pl. 3, figs. 13, 14. Syntypes (3): RMNH.RENA.242a– c, by original designation. Type locality: “du Mont Parang à l’île de Java ” (= Gunung Parang, Purwakarta Regency, West Java, Indonesia).

Brown Kukri Snake ( Figure 19F )

Simotes purpurascens var. F— Ģnther, 1858b: 26.

Lycodon dennysi —Dennys, 1880: 3.

Simotes goniospilus Dennys, 1880a: 3 .— Dennys, 1881a: 2.— Dennys, 1881b: 2.

Simotes dennysi — Blanford, 1881: 215, 218–219.

Simotes purpurascens —Sclater, 1891a: 23.— Boulenger, 1894: 218.— Flower, 1896: 884.— Flower, 1899: 671.—Ridley, 1899: 198, 208 (Bukit Timah Road).— Boulenger, 1912: 148.— Hanitsch, 1912b: 16.— de Rooij, 1917: 126.

Simotes purpurascens var. B— Hanitsch, 1898: 20.

Simotes cyclurus var. E (non-Cantor, 1839b)— Hanitsch, 1899: 12 (Botanic Gardens).— Hanitsch, 1912b: 16.

Simotes cyclurus (non-Cantor, 1839b)—Ridley, 1899: 208.

Simotes purpurascens —Sworder, 1923: 64.—Sworder, 1924b: 21 (“near Mandai Railway Station” [GBF]).

Holarchus cyclurus (non-Cantor, 1839b)—Sworder, 1923: 64.—Sworder, 1924b: 21.

Oligodon purpurascens — Smith, 1930: 53.—F.L.K. Lim & M.T.-M. Lee, 1989: 115.—K.K.P. Lim & L.M. Chou, 1990: 54.—K.K.P. Lim & F.L.K. Lim, 1992: 60, 146.—L.M. Chou et al., 1994: 105.— K.K.P. Lim, 1994b: 331.— David & Vogel, 1996: 102.— Manthey & Grossmann, 1997: 371.— Cox et al., 1998: 59.—Chan-ard et al., 1999: 34.—K.P. Lim & F.L.K. Lim, 2002: 146.—T.M. Leong & L.L. Grismer, 2004: 15.—N. Baker & K.P. Lim, 2008: 105, 161.—K.K.P. Lim et al., 2008: 265.— Das, 2010: 293.—L.L. Grismer, 2011a: 206.—P.K.L. Ng et al., 2011: 272.—van Rooijen et al., 2011: 216.—N. Baker & K.P. Lim, 2012: 105, 161.— Das, 2012a: 57.—Wallach et al., 2014: 502.—Chan-ard et al., 2015: 179.— Das, 2018: 69.—O’Shea, 2018: 200.— Charlton, 2020: 183.—K.K.P. Lim, 2020: 2, 5 (Sime Road Internment Camp [= SICC]).—A.Y.H. Goh, 2022: 1 (Terentang Trail [= MNF]).

Oligodon purpurascens purpurascens — de Haas, 1950: 557.—Taylor, 1965: 770.— Iskandar & Colijn, 2001: 75.—Tillack & R. Ģnther, 2010: 277, 278.— de Lang, 2017: 177.

Holarchus purpurascens — Cross, 2020m: 1, 5 (Sime Road Camp [= SICC]) .— Cross, 2020n: 2, 7 (Sime Road Camp [= SICC]) .

Remarks. Oligodon purpurascens has been recorded from Singapore under three different names: Simotes purpurascens , S. dennysi , and S. (or Holarchus ) cyclurus (see references above), a consequence of the species colour dimorphism occurring in a purple or brown phase. Variation in O. purpurascens was known since Ģnther (1858b) who first reported it from Singapore from two specimens at NHMUK that he classified as “variety F” (purple phase). Dennys (1880) used the name Lycodon dennysi and then Simotes goniospilus to refer to a grey colour morph specimen at the Raffles Museum. This specimen was clearly believed to be a new species and the names applied may have been tentative designations given to Dennys from someone at NHMUK, most likely Blanford who later described S. dennysi using that specimen as the holotype ( Table 1 ). Simotes goniospilus could have been a misspelling of the junior synonym S. aphanospilus , if the specimen was indeed confused with O. ancorus , a species endemic to the Philippines (Wallach et al. 2014). Nonetheless, Boulenger (1894) later synonymised it with O. purpurascens . Hanitsch (1899, 1913), Ridley (1899), and Sworder (1923, 1924b) each listed S. cyclurus to describe a specimen collected at SBG by Ridley in 1897 ( Hanitsch 1899) which Smith identified as an aberrant O. purpurascens (Sworder 1924) . Additional early records of O. purpurascens include a specimen at ZSI (Sclater 1891a), a specimen donated by a governor of Singapore to NHMUK ( Boulenger 1894), one that Ridley (1899) captured on Bukit Timah Road, one Sworder (1924b) collected near Mandai Railway Station in June 1923, and two specimens at LKCNHM collected at Changi, ZRC. 2.3877 in 1927 and ZRC. 2.3878 in February 1928. Oligodon purpurascens is exceedingly rare in Singapore not having been reported since June 1923 (Sworder 1924b), until a photograph of one from Singapore Zoo (F.L.K. Lim pers. comm.) was published 69 years later ( Table 2 ) in Lim & Lim (1992). However, Cross (2020m) recorded two specimens from Sime Road Internment Camp in 1944 that went unpublished until now ( Lim 2020). Since Lim & Lim (1992), three specimens have been collected, ZRC.2.6216 from USR on 9 October 2006, ZRC.2.6719 from OUTR on 26 August 2007, and ZRC.2.7243 from Mandai Track 7 on 7 May 2017, and a live individual was photographed on 18 May 2001 at LPF ( Fig. 19F ) (B.Y.H. Lee pers. comm.) and at MNF on 27 July 2022 (Goh 2022).

Occurrence. Known from a few specimens predating 1923 and five specimens after 1992. Rare.

Singapore conservation status. Critically Endangered.

Conservation priority. Highest.

IUCN conservation status. Least Concern [2012].

LKCNHM & NHMUK Museum specimens. Singapore (no locality) : BMNH 1883.11 .28.13 (no date); Botanic Gardens : ZRC.2.3879 (Mar-1897); Changi : ZRC.2.3877 (1927), ZRC.2.3878 (Feb-1928); Mandai Track 7 : ZRC.2.7243 (07-May-2017); Old Upper Thomson Road : ZRC.2.6719 (26-Aug-2007); Upper Seletar Reservoir : ZRC.2.6216 (09-Oct-2006) .

Additional Singapore museum specimens. No specimens.

Singapore localities. Bukit Timah Road*—Changi*—Gali Batu Forest—Lower Peirce Forest—MacRitchie North Forest—Mandai Track 7—Old Upper Thomson Road—Singapore Botanic Gardens*—Singapore Island Country Club—Singapore Zoo—Upper Seletar Reservoir.

Figures

FIGURE 19. A) Liopeltis tricolor, B) Lycodon capucinus, C) Lycodon subannulatus, D) Lycodon subcinctus, E) Oligodon octolineatus, F) Oligodon purpurascens, G) Oligodon signatus, and H) Ptyas carinata. Photographs by: Evan S.H. Quah [A], Alex Figueroa [B, E, G], Mary-Ruth Low [C], Daniel J.J. Ng [D], Benjamin Y.H. Lee [F], and Law Ing Sind [H],