Scaphander andamanicus Smith, 1894

Siegwald, Justine & Malaquias, Manuel António E., 2025, Bringing light into deep-sea biodiversity: a systematic revision and molecular phylogeny of the genus Scaphander Montfort, 1810 (Gastropoda: Cephalaspidea), with a focus on the Indo-Pacific, Zoological Journal of the Linnean Society 203, pp. 1-60 : 21-22

Scaphander andamanicus Smith, 1894

( Figs 9 , 10 ; Table 2)

Scaphander andamanicus Smith, 1894: 167 , pl. 4, fig. 15; Pilsbry 1895: 235, frontispiece, fig. 18; Kobelt 1896: 9, pl. 5, fig. 10; Smith 1904: 5; 1906: 247; Annandale and Stewart 1909: pl. 19, figs 7, 8.

Taxonomic history: Scaphander andamanicus was described from a shell collected by the Investigator in the Andaman Sea ( Smith 1894). Several additional shells were later recorded from the Bay of Bengal and the Andaman Sea from material collected during the same expedition ( Smith 1904, 1906).

Type material: Scaphander andamanicus Smith, 1894 — India: Andaman Sea , 457 m, holotype, NZSI M.5271 , H = 18 mm; one paratype, NHMUK 1894.9.11.31 , H = 24 mm, images seen ( Fig. 9A ) .

Other material examined: Sri Lanka: south of Ceylon, 1207 m, four sh., NHMUK 1906.10.12.69-70, H = 18–25 mm, images seen ( Fig. 9B ).

Diagnosis: Shell external, ovate, orange to dark reddish brown. Spiral sculpture composed of punctations, distinct or interconnected. Apex rounded, with posterior edge of outer lip rising above it in a wing.

Shell ( Fig. 9 ): Maximum H observed = 24 mm. Shell ovoid to rounded, only one whorl visible. Aperture wide, as long as shell, narrowing posteriorly. Apex rounded, spire concealed. Posterior edge of outer lip protruding beyond apex in a small wing. Parietal wall covered with thick, smooth white callus. Spiral sculpture composed of punctuated striations. Punctations ovoid to sub-rectangular pits, close together, sometimes interconnected. Periostracum orange to dark reddish-brown. Shell white.

Radula: Unknown.

Digestive tract: Unknown.

Male reproductive system: Unknown.

Ecology: Found between 338 and 1714 m depth. Feeding habits unknown.

Distribution ( Fig. 10 ): Andaman Sea ( Smith 1894) and Bay of Bengal ( Smith 1904, 1906).

Remarks: This species is known from a few shells only and bears a strong resemblance to Scaphander sibogae Schepman, 1913 ; however, the type and original description of S. andamanicus present a wing-like posterior lip, but less sharp than the one of S. sibogae . Furthermore, given that distinct species of Scaphander can have remarkably similar shells (see S. otagoensis , S. interruptus , and S. amygdalus sections) and that there are no records of S. sibogae westwards of Indonesia, both species are kept as valid. Future sampling in the Bay of Bengal might revise this hypothesis, in which case S. andamanicus would become the senior synonym of S. sibogae .

Figures

Figure 9. Shells of Scaphander andamanicos. A, Andaman Sea (paratype, NHMUK 1894.9.11.31, H = 24 mm, images courtesy of the NHMUK). B, south of Sri Lanka (NHMUK 1906.10.12.69-70, H = 24 mm, images courtesy of the NHMUK).

Figure 10. Geographical distribution of Scaphander andamanicos, Scaphander cancellatos, Scaphander illecebrosos, and Scaphander sibogae. Geographical records are based on studied material and reliable literature records.