Crucigera tricornis Gravier, 1906

(Fig. 1A, B)

Serpula (Crucigera) websteri var. tricornis Gravier, 1906a: 111 –112 [Red Sea; description].—1906b: pl. 8, fig. 289; 1908: 117–119, figs 473–475 [same].

Serpula websteri tricornis . — Solis-Weiss et al. 2004: 18 [Gulf of Tadjoura, Gulf of Aden, holotype, MNHN POLY TYPE 734].

Crucigera tricornis . — Imajima 1977: 92 –94, fig. 3 [Ogasawara Islands, Southern Japan; description]; ten Hove & Jansen- Jacobs 1984: 161–162 [detailed description as a part of revision]; Imajima & ten Hove 1984: 42–43, fig. 3a, b [Ponape Island, Majuro Atoll; Lizard Island]; Vine & Bailey-Brock 1984: 139 [Red Sea]; Vine 1986: 89 –90 [Red Sea; figure]; Imajima & ten Hove 1986: 3 [Solomon Islands]; Bailey-Brock 1987: 282 [Tonga]; ten Hove 1993: 83 [Seychelles, name only]; 1994: 114 [same]; Hassan 1998: 51 [Red Sea; diagnosis]; Fiege & Sun 1999: 111 [Hainan Island, China]; Sun & Yang 2001b: 210 –211, fig. 1A–F [Hainan Island]; Wehe & Fiege 2002: 124 [synonomy]; Kupriyanova et al. 2008: 426, 428, 430–43, fig. 1D [Lizard Island; DNA data]; ten Hove & Kupriyanova 2009: 36, fig. 3D [Lizard Island]; Bailey-Brock et al. 2012: 969 [Marshall Islands].

Material examined. AM W.28308 (2), Turtle Beach, 14°40'S, 145°27'E, undersides of dead and living corals, coll. H. ten Hove, 22 Jun 1983; AM W.28344, stn.21, south of South Island, 14°42'S, 145°28'E, sloping silty reef, little coral cover, 20 m, coll. H. ten Hove & P. Hutchings, 6 Mar 1986; AM W.43970, MI QLD 2354; AM W.47309, Day Reef, outer Fore Reef, 14°28'30''S, 145°32'12''E, coral rubble, 30 m, coll. S. Smith; AM W.47313, Day Reef, midshelf of Fore Reef, 14°28'18''S, 145°31'48''E, coral rubble, 10 m, coll. M. Blazewicz-Paskowycz, 13 Feb 2009; AM W.47345, Hicks Reef outer Barrier, 14°28'48''S, 145°29'18''E, coral rubble, 2–18 m, coll. C. Watson & K. Mills, 14 Feb 2009; AM W.47351, inter-reef sand, 14°23'24''S, 145°31'48''E, artificial substrate, 10 m, coll. M. Timmers, 9 Feb 2009; AM W.47354, same, 10 Feb 2009; AM W.47450, stn.G238, east lagoon near Bird Islet, 10 m, coll. G. Rouse & E. Kupriyanova, 31 Oct 2005; MAGNT W025495, North Point, Fore Reef, 14°39'S, 145°27'E, coral rubble, 2 m, coll. C. Watson, 12 Apr 2008; MAGNT W025496, Big Vicky Reef, northwest of Palfrey Island, 14°0'S, 145°0'E, coral rubble, 3 m, coll. K. Mills, 12 Apr 2008; MAGNT W025498, off Granite Bluff, Fore Reef, 14°0'S, 145°0'E, coral rubble, 15 m, coll. M. Blazewicz-Paskowycz, 17 Apr 2008; MAGNT W025501, Yonge Reef, 14°34'30''S, 145°36'18''E, coll. C. Glasby, 20 Apr 2008; SAM E3587, stn.G231, off Coconut Beach, 14°41'S, 145°28'E, G. Rouse & E. Kupriyanova, 26 Oct 2005; ZMA V.Pol. 4578 (4), stn.18, lagoon near east entrance, sheltered side of reef, near sandy bottom, 2–20 m, coll. H. ten Hove, 3 Mar 1986; ZMA V.Pol. 4579, stn.17, Palfrey Island, south of lighthouse, 14°40'S, 145°28'E, coral heads on sandy bottom, 7 m, coll. H. ten Hove, P. Hutchings & M. Reid, 2 Mar 1986.

Diagnosis. Operculum a shallow funnel with three large elongated proximal processes; tube with 6–9 longitudinal keels (Fig. 1A, B).

Remarks. According to descriptions and illustrations of Imajima (1977) and Imajima & ten Hove (1984), the tube of this species is white with 7–9 sinuous longitudinal keels, with a row of pits between the keels. However, at least one speciemen from Lizard Island (Fig. 1 B) had a yellowish tube with straight longitudinal keels and numerous transverse ridges.

Distribution. Red Sea, Japan, Australia; widely distributed in the Indo-West Pacific.