Hydrophis hardwickii (Gray, 1834) — Native.

Lapemis Hardwickii Gray, 1834 (in 1832–1835): pl. 87, fig. 2. Holotype: BMNH 1946.1.18.39, by original designation. Type locality: None stated/traced; later designated as “ India ” by Gray (1849: 44).

Hardwicke’s Spine-bellied Sea Snake

(Figures 22B & 22C)

Singapore records.

Hydrophis hardwickii —Steindachner, 1867: 85.— Charlton, 2020: 74.

Enhydris hardwickii — Boulenger, 1896: 301.— Flower, 1896: 892.—Ridley, 1899: 209.— Boulenger, 1912: 193.

Enhydris hardwickei [sic]— de Rooij, 1917: 240.

Lapemis hardwickii —Sworder, 1923: 70.— Smith, 1926: 108.— Lim, 1988d: 75 (Changi North).—F.L.K. Lim & M.T.-M. Lee, 1989: 116.— Gopalakrishnakone, 1990: 3.

Lapemis curtus — Gritis & Voris, 1990: 2–4, 7, 9–10.—K.K.P. Lim & L.M. Chou, 1990: 55.—K.K.P. Lim & F.L.K. Lim, 1992: 93, 149.—L.M. Chou, 1993: 153.—L.M. Chou et al., 1994: 105.—K.P. Lim & F.L.K. Lim, 2002: 148.— Das, 2010: 323.—P.K.L. Ng et al., 2011: 302.— Das, 2012a: 98.—Wallach et al., 2014: 362.—Chan-ard et al., 2015: 263.

“ Lapemis ” —L.W.H. Tan & P.K.L. Ng, 1992a: 145.

Lapemis curtus hardwickii — Iskandar & Colijn, 2001: 139.

Hydrophis curtus — Das, 2018: 111.

Remarks. A specimen of H. hardwickii was first collected from Singapore between 1857 and 1859 during the Austrian Novara expedition and reported by Steindachner (1867). Boulenger (1896) next reported it from two specimens he examined at NHMUK that were collected by Swinhoe. For 85 years, H. hardwickii was not reported from Singapore (Table 2) until Voris and Jeffries collected two specimens around kelongs at LCK in 1981. They also amassed over 94 specimens from Kangkar Fish Market, but these were obtained from around Horsburgh Lighthouse on Pedra Branca (which have been excluded; refer to “A note on sea snakes in Singapore ” above) and beyond, in the South China Sea. LKCNHM has two additional specimens, one from LKC collected on 14 February 1996 and one from Sentosa collected on 9 August 2006 (Fig. 22B), and NHMUK has one additional specimen from Siglap. The only other published account was of a dead specimen collected from the beach at Changi North on 2 October 1988 (Lim 1988d). Based on the number of specimens collected by Voris and Jeffries, H. hardwickii appears as if it may be common around Singapore, but this remains unknown due to lack of research on sea snakes in Singapore.

Occurrence. Known only from two specimens predating 1896, two specimens from LCK in 1981, and one specimens from Changi in 1988. Rare.

Singapore conservation status. Endangered.

Conservation priority. Highest.

IUCN conservation status. Not Evaluated.

LKCNHM & NHMUK Museum specimens. Singapore (no locality): BMNH 1870.1.4.10 (no date), BMNH 1936.7.9.3–4 (no date); Lim Chu Kang: ZRC.2.2136 (11-Apr-1981), ZRC.2.4754 (14-Feb-1996), Sentosa: ZRC.2.6212 (09-Aug-2006); Siglap: BMNH 1936.7.9.2 (no date).

Additional Singapore museum specimens. No museum specimens.

Singapore localities. Changi North—Lim Chu Kang—Katong*—Sentosa—Siglap*.