Scaphander nobilis Verrill, 1884

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 : 15-16

Scaphander nobilis Verrill, 1884

( Figs 3–5 ; Table 2)

Scaphander nobilis Verrill, 1884: 209 , 210, pl. 32, fig. 18a–d; Dall 1889a: 86; 1889b: 53, pl. 64, fig. 106; Pilsbry 1893: 249–250, pl. 32, figs 31, 32; Maury 1922: 49; Dall 1927: 26; Johnson 1934: 147; Clarke 1962: 40; Bouchet 1975: 335–336, fig. 7A–C, pl. 3, figs a–c, map 5; Eilertsen and Malaquias 2013a: 406, 408, 410, figs 2, 8, 15.

Scaphander (Bucconia) nobilis — Dall 1890a: 16–17, pl. 10, fig. 9; Thiele 1925: 319; Bullis 1956: 6, fig. 2A, B.

Bulla millepunctata Locard, 1897: 52–54 , pl. 2, figs 3–6; Pallary 1912: 21.

Atys millepunctatus — Martens and Thiele 1903: 15, pl. 5, fig. 20.

Bulla (Bullocardia) millepunctata — Nordsieck 1972: 29, pl. P7, fig. 25.

Scaphander stigmatica Dall, 1927: 26 .

Scaphander (Bucconia) stigmatica — Bullis 1956: 6, fig. 2D, E.

Scaphander stigmaticus — Marcus 1974: 334, figs 51–56.

Taxonomic history: Scaphander nobilis was described by Verrill (1884) based on shells from the Albatross expedition collected in Delaware Bay (Atlantic, USA). Locard (1897) described a similar species, Bulla millepunctata , from specimens sampled during the Talisman expedition off the Azores and coast of Sahara, which was reassigned by Martens and Thiele (1903) to the genus Atys . Dall (1927) described S. stigmatica based on Caribbean shells he had previously identified as S. nobilis ( Dall 1889a, 1889b). Bouchet (1975) synonymized B. millepunctata and S. stigmatica with S. nobilis , which Eilertsen and Malaquias (2013a) confirmed in their study of the genus in the Atlantic.

Type material: Scaphander nobilis Verrill, 1884 — Northwestern Atlantic: Delaware Bay , Albatross Expedition , station 2102, 38°44'00"N, 72°38'00"W, 2211 m, holotype, USNM 35641 , H = 34.2 mm, images seen ( Fig. 2A ) . Bulla millepunctata Locard, 1897 — Northeastern Atlantic: north of the Azores, Talisman Expedition , station DR135, 43°15'00"N, 19°19'00"W, 4163 m, syntype MNHN-IM-2000-38367, H = 41 mm, images seen ( Fig. 2C ); west of the Sahara, Talisman Expedition , station DR76, 25°01'00"N, 16°55'00"W, 2638 m, syntype, MNHN-IM-2000-38276, H = 43 mm, images seen. Scaphander stigmatica Dall, 1927 — Caribbean: south of Cuba, Albatross Expedition , station 2127, 19°45'00"N, 75°04'00"W, 2997 m, holotype, USNM 95196, H = 35.4 mm, images seen ( Fig. 2B ).

Other material examined: Atlantic: Azores, one spc., sequenced, ZMBN 127875, H = 24 mm; Bay of Biscay, one spc., dissected, MNHN-IM-2019-11702, H = 27 mm; one spc., MNHN-IM-2019-11720, H = 27 mm; one spc., dissected, MNHN-IM-2009-29696, H = 39 mm; one spc., dissected, MNHN-IM-2016-5767, H = 40 mm. Indian Ocean: Walters Shoals, South Plain, one spc., dissected and sequenced, MNHN-IM-2013-67215, H = 23 mm; one sh., MNHN-IM-2013-67214, H = 15 mm.

Diagnosis: Shell ovoid, white. Spiral sculpture composed of round to sub-rectangular punctuations. Apex rounded. Posterior edge of outer lip rising above apex in sharp curved wing. Rachidian teeth sub-quadrate. Prostate round to club-shaped. Penial papilla narrow, covered with warts.

Shell ( Fig. 4 ): Maximum H observed = 40 mm. Shell ovoid to elongated oval, only one whorl visible. Aperture wide, as long as shell, narrowing posteriorly. Spire concealed. Posterior edge of outer lip rising in sharp curved wing protruding well beyond apex. Parietal wall covered with slight, smooth white callus. Spiral sculpture composed of punctuated striations. Punctations round to sub-rectangular. Thin, translucent to pale yellow periostracum. Shell white.

Radula ( Fig. 5A–C ): Radular formula 20 × 1.1.1 (H = 40 mm). Lateral teeth curved, with fine denticulation on inner edge. Rachidian teeth sub-quadrate.

Digestive tract ( Fig. 5D, E ): Salivary glands medium long, surface uneven. Paired gizzard plates kidney-shaped to sub-triangular.

Male reproductive system ( Fig. 5F, G ): Penial chamber cylindrical, lined with soft longitudinal ridges near genital opening, with soft warts near prostatic duct entrance. Penial papilla long, narrow, covered with warts and wrinkles. Penial chamber separated from prostate by medium prostatic duct, narrowing towards prostate. Prostate round to club-shaped.

Ecology: Found between 1493 and 4255 m depth. Feeds on foraminifera, tubicolous polychaetes, and small gastropods ( Eilertsen and Malaquias 2013a; present study).

Distribution ( Fig. 3 ): Western Atlantic from Martha’s Vineyard, USA ( Dall 1927), Gulf of Mexico ( Bullis 1956), and from the Caribbean Sea to South Brazil ( Marcus 1974). Eastern Atlantic from the Bay of Biscay, the Azores ( Bouchet 1975), and the northwestern coast of Africa from the Canaries to Senegal (Locard 1897, Marcus 1974). Southwestern Indian Ocean, Walters Shoals (present study).

Remarks: Three specimens are labelled as syntypes for B. millepunctata at the Natural History Museum in Paris. However, examination of images of these specimens revealed that one of them (MNHN-IM-2000-27696) did not fit Locard (1897)’s description and illustration. The shell of this specimen instead has the apparent flat spire and inflated shape characteristic of S. imperceptus and expands the range of this species from Mauritania to north of the Azores (see Fig. 14 ).

As highlighted by Eilertsen and Malaquias (2013a) and discussed above, reports of Western Pacific species S. mundus in the Atlantic (Locard 1897, Pallary 1912, Marcus and Marcus 1966, Pequegnat 1983) should be considered misidentifications of S. nobilis . Another Western Pacific species, S. cornus , is remarkably similar to S. nobilis and has commonly been confused with S. mundus ( Valdés 2008) , which might explain those misidentifications. However, S. nobilis has a more elongated shell and a muscular penial papilla, whereas S. cornus has a rounder shell and lacks a penial papilla.

Figures

Figure 2. Anatomical details of Scaphander mondos. A, radula, Australia, Queensland, Coral Sea Commonwealth Marine Reserve (AM C.519372, H = 22 mm). B, rachidian teeth (AM C.519372, H = 22 mm). C, detail of lateral teeth (AM C.519372, H = 22 mm). D, anterior part of digestive tract, South China Sea, off Taiping Island (MNHN-IM-2013-44305, H = 30 mm). E, gizzard plates (AM C.519372, H = 22 mm). F, male reproductive system (AM C.519372, H = 22 mm).G, penial papilla, South China Sea, off Taiping Island (MNHN-IM-2013-44310, H = 26 mm). Scale bars: A, G = 200 µm; B, C = 20 µm; D, F = 1 mm; E = 2 mm.

Figure 3. Geographical distribution of Scaphander cornus, Scaphander mondos, and Scaphander nobilis. Geographical records are based on studied material and reliable literature records.

Figure 4. Shells and SEM image of the shell sculpture of Scaphander nobilis. A, Northwestern Atlantic, Delaware Bay (holotype, USNM 35641, H = 34.2 mm, images courtesy of the USNM). B, Caribbean Sea, south of Cuba (holotype, Scaphander stigmatica, USNM 95196, H = 35.4 mm, images courtesy of the USNM). C, Northeastern Atlantic (syntype, Bolla milleponctata, MNHN-IM-2000-38367, H = 41 mm, images courtesy of the MNHN). D, Southwestern Indian Ocean, Walters Shoals (MNHN-IM-2013-67215, H = 23 mm). E, Southwestern Indian Ocean, Walters Shoals (MNHN-IM-2013-67214, H = 15 mm).F, Northeastern Atlantic, Bay of Biscay (MNHN-IM-2019-11702, H = 27 mm). G, Southwestern Indian Ocean, Walters Shoals (MNHN-IM-2013-67215, H = 23 mm). H, Southwestern Indian Ocean, Walters Shoals (MNHN-IM-2013-67214, H = 15 mm). I, Northeastern Atlantic, Bay of Biscay (MNHN-IM-2019-11702, H = 27 mm). J, Southwestern Indian Ocean, Walters Shoals (MNHN-IM-2013-67214, H = 15 mm). Scale bar: J = 200 µm.

Figure 5. Anatomical details of Scaphander nobilis. A, radula, Northeastern Atlantic, Bay of Biscay (MNHN-IM-2019-11702, H = 27 mm). B, rachidian teeth (MNHN-IM-2019-11702, H = 27 mm). C, detail of lateral teeth (MNHN-IM-2019-11702, H = 27 mm).D, anterior part of digestive tract (MNHN-IM-2019-11702, H = 27 mm). E, gizzard plates, Southwestern Indian Ocean, Walters Shoals (MNHN-IM-2013-67215, H = 23 mm). F, male reproductive system (MNHN-IM-2019-11702, H = 27 mm). G, penial papilla (MNHN-IM-2019-11702, H = 27 mm). Scale bars: A, G = 200 µm; B, C = 20 µm; D, F = 1 mm; E = 2 mm.

Figure 14. Shell of Scaphander planeticos (A), Scaphander tortoosos (B), and Scaphander imperceptos (C, D). A, Northern Pacific Ocean, north of Marquesas Islands (holotype, Scaphander (Sabatina) planeticos, USNM 110748, H = 8 mm, images courtesy of the USNM). B, Indonesia, Sulawesi (holotype Meloscaphander sibogae, ZMA.MOLL.136944, H = 16 mm; images taken by K.Hasegawa and courtesy of Naturalis Biodiversity Center). C, Northeastern Atlantic, northeast of the Azores (syntype, Bolla milleponctata, MNHN-IM-2000-27696, H = 14.8 mm, images courtesy of the MNHN). D, Northeastern Atlantic, off Mauritania (holotype, Meloscaphander imperceptos, MNHN-IM-2000-27680, H = 19.3 mm, images courtesy of the MNHN).