Sinezona kayae, Geiger, Daniel L. & Mclean, James H., 2010

Geiger, Daniel L. & Mclean, James H., 2010, New species and records of Scissurellidae and Anatomidae from the Americas (Mollusca: Gastropoda: Vetigastropoda), Zootaxa 2356, pp. 1-35 : 4-7

Sinezona kayae n. sp.

( Figures 1–3 )

Sinezona insignis (non Smith, 1910): Kay, 1979: 39, figs. 7C, 9D–F.

Sinezona sp.: Lozouet, 1986: 111 [noted difference from true Sin. insignis ].

Type material. Holotype ( SBMNH 83542 ) . Paratypes: from type locality ( SBMNH 83543, 5); 0 m, NE coast, Oahu, Hawaii, USA, 21.620˚N, 157.910˚W (UF 350462, 1); 0 m, off Kala Place, Diamond Head, Oahu, Hawaii, USA, 21.250˚N, 157.800˚W ( SBMNH 351023, 5: formalin fixed and ethanol preserved; SBMNH 351024, 4: formalin fixed and dried. SBMNH 351025, 1: ethanol fixed and preserved); Hakipu’u Reef, Kaneohe Bay, Oahu, Hawaii, USA ( BPBM 261475, 1: complete). Moku Manu Island, Kaneohe Bay, Oahu, Hawaii, USA ( BPBM 263630, 1: complete).

Type locality. 0 m, Haleiwa, Oahu , Hawaii, USA, 21.590˚N, 158.113˚W .

Etymology. Named in honor of the late Alison E. Kay of the University of Hawaii for her many accomplishments with respect to the Hawaiian malacofauna.

Description. Shell small (to 0.65 mm), depressed ovoid. Protoconch 0.75 whorls, with 19–20 strong axials, no apertural varix, apertural margin slightly sinusoid. TI of 0.75 whorls, only axial sculpture, approximately 13 fine, distinct ribs, interstices with fine irregular growth lines. TII slightly> 0.5 whorl, on shoulder, axial sculpture slightly diminished in strength towards selenizone/foramen, approximately five indistinct axials appear towards aperture; base with fine, distinct axials only, base forming angle with walls of umbilicus. Selenizone approximately 0.25 whorl, slit closed to form foramen. Aperture ovoid, roof strongly protracted, adumbilical margin straight. Umbilicus open, quite wide, border to base with spiral cord (funiculus). Operculum thin, round, multispiral, with central nucleus.

Radula ( Fig. 3 A–B). Rachidian triangular, cusp with 5 denticles, central one largest. Lateral teeth 3–5 similar, 3–4 denticles on outer margin. Lateral tooth 4 reduced, pointed. Lateral tooth 5 broadened with approximately 6–8 denticles on inner margin. Radular interlock of central field moderate. Inner marginal teeth with two small denticles on inner margin of cusp, terminal denticle largest, approximately five denticles on outer margin. Outer marginal teeth spoon shaped, many fine bristles on each side of cusp.

Differential diagnosis. Sinezona kayae has more distinct and fewer axials and is more depressed than Sin. insignis from South Africa. Sinezona costulata Geiger & Sasaki, 2009 , from temperate Japan is overall wider, lacks the strong spiral cord bordering the umbilicus, and the axial lamellae on the base do not reach the selenizone. Sinezona danieldreieri Geiger, 2008 , from the Indo-Pacific has an overall broader shell, more and finer axial cords on the teleoconch, axial cords on the shoulder reaching from the suture to the selenizone, and a protoconch with fewer (9–15 vs. 19–20) broader strong axial cords.

Distribution. Hawaii, USA.

Specimen records. 30 m, off Waikiki, Oahu, 21.270˚N, 157.840˚W (LACM 75-96, 1). 30 m, Koloa, Kauai, 21.883˚N, 159.475˚W (LACM 75-97, 1). 0 m, off Kala Place, Diamond Head, Oahu. 15/X/2001 (DLG 223, 12 formalin fixed; DLG 231, 11 ethanol fixed). 0 m, Ka’awa, Oahu, Hawaii, USA, 21.555˚N, 157.851˚W (DLG 473, 2). 0 m, Kona Village Resort, Big Island, Hawaii, USA, 19.831˚N, 155.988˚W (DLG 485, 3: complete). 0 m, Kala, Oahu, Hawaii, USA, 21.261˚N, 157.787˚W (DLG 495, 7: complete). 0 m, Kona Village Resort, Big Island, Hawaii, USA, 19.831˚N, 155.988˚W (DLG 751, 6). 0 m, off Kala Place, Diamond Head, Oahu, Hawaii, USA (DLG 752, 1). 0 m, off Kala Place, Diamond Head, Oahu, Hawaii, USA (DLG 753, 4). 0 m, Makai Pier, Makapu Beach, Oahu, Hawaii, USA (UF 350463, 1). 10 m, Maile, Oahu, Hawaii, USA (UF 350460, 1). 60 m, Kepuhi Point, Oahu, Hawaii, USA (UF 350461, 2).

Remarks. Herbert (1986) included Kay’s (1979) listing and illustrations of this new species in the synonymy of the South African species, although noting that (p. 628) “the identity of her specimens requires confirmation as the occurrence of S. insignis , an essentially warm temperate species, in the tropical Pacific is surprising.”

Figures

FIGURE 1. Sinezona kayae n. sp., holotype, SBMNH 83542. 0 m, Haleiwa, Oahu, Hawaii, USA, 21.590 ˚ N, 158.113 ˚ W. Scale bar shell = 500 µm. Scale bar protoconch = 100 µm.

FIGURE 2. Sinezona kayae n. sp., paratypes. A – B. SBMNH 83543. 0 m, Haleiwa, Oahu, Hawaii, USA, 21.590 ˚ N, 158.113 ˚ W. C. UF 350462. 0 m, NE coast, Oahu, Hawaii, USA, 21.620 ˚ N, 157.910 ˚ W. Scale bar shell = 500 µm. Scale bar protoconch = 100 µm.

FIGURE 3. Sinezona kayae n. sp. 0 m, Kona Village Resort, Big Island, Hawaii, USA, 19.831 ˚ N, 155.988 ˚ W (DLG 485, 3: complete). A – B: Radula. A: Central field. B: Lateral tooth 5 and marginal teeth. C. Operculum. Scale bars radula = 10 µm. Scale bar operculum = 200 µm.