Coralliophila australis, Oliverio, 2009

Oliverio, Marco, 2009, Diversity of Coralliophilinae (Mollusca, Neogastropoda, Muricidae) at Austral Islands (South Pacific), Zoosystema 31 (4), pp. 759-789 : 765-766

Coralliophila australis n. sp.

( Figs 3 D-H; 12A)

TYPE MATERIAL. — Holotype: Rapa Is. , East of Tupuaki Bay , ATELIER RAPA 2002 , stn 21, 27°34.2’S, 144°20.6’W, 5 m, dd crabbed ( MNHN 20965 ; Fig. 3D, E ).

Paratypes: West of Rapa, BENTHAUS , stn DW 1894, 27°40.1’S, 144°21.5’W, 100 m, 1 dd ( MNHN 20966). — Marotiri Is., stn DW 1879, 27°55’S, 143°30.1’W, 52 m, 3 dd ( Fig. 3F, G ), 1 juv dd ( MNHN 20967; Fig. 3H ). — SE of Tauturou Is., ATELIER RAPA 2002 , stn 12, 27°40.5’S, 144°16.7’W, 52 m 1 dd ( MNHN 20968).

TYPE LOCALITY. — Rapa Is. , East of Tupuaki Bay, 27°34.2’S, 144°20.6’W, 5 m.

OTHER MATERIAL EXAMINED. — Banc Président Thiers, BENTHAUS, stn DW 1927, 24°39’S, 146°01.6’W, 95-105 m, 1 juv dd. — Rurutu (Avera), stn DW 1996, 22°29.1’S, 151°21.9’W, 489-1050 m, 1 dd. — Banc Président Thiers, stn DW 1926, 24°38.2’S, 146°00.8’W, 50-90 m, 1 juv dd.

Pointe Komire, ATELIER RAPA 2002 , stn 3, 27°34’S, 144°19.7’W, 21 m, 1 dd. — Off Ahurei Bay, stn 6, 27°36.8’S, 144°16.7’W, 42 m, 2 dd. — NE of Pointe Komire, stn 26, 27°33.0’S, 144°19.1’W, 53 m, 1 dd. — Vavai, stn 32, 27°35.0-35.8’S, 144°22.7-23.0’W, 15-20 m, 1 dd.

DESCRIPTION. — Shell of medium size for the genus, 37.5 mm high, 22 mm wide, fusiform with rounded shoulder, thick. Protoconch missing in the holotype.

DISTRIBUTION. — Coralliophila australis n. sp. is known only on empty shells from Austral Islands, in 5-489 m (5-53 m ATELIER RAPA 2002 ; 52-489 m BENTHAUS).

DESCRIPTION

Teleoconch of 5+ whorls (tips missing in the holotype). Spire high, conical, with convex sides, suture incised. Last whorl about ⅔ of total height, curved at periphery, moderately constricted at base. Aperture long, oval, tapering anteriorly. Outer lip crenulated on exterior, smooth internally. Inner lip gently arcuate posteriorly, straight anteriorly, callous. Siphonal canal long, broadly open; umbilical area wide, with twisted, imbricate fasciole, umbilical chink narrow and short.

Teleoconch spiral sculpture of irregularly alternating major cords and minor cordlets. A total of 14 cords and 7 cordlets on last teleoconch whorl; 7 cords and 4 cordlets visible above aperture. Cords and cordlets covered by imbricate scaly spines. Axial sculpture of 8 broad prosocline ribs on the last whorl (10 on the preceeding ones), fading out over base.

Shell ground colour ivory-white, inside of aperture bright pink-lilac.

REMARKS

The protoconch of a juvenile paratype is of 3.6 whorls ( Fig. 12A ), 750 µm high and 720 µm wide at the base. Protoconch I of 1 whorl, with traces of pustules. Protoconch II of 2.6 whorls, with 2 weak spiral keels, sculptured by a series of subsutural prosocline threads and a series of similar threads over each keel. A diffuse granulation is present in the interspaces.

Coralliophila australis n. sp. is similar to several species of the (probably monophyletic) group of C. violacea (Kiener, 1836) . The spiral sculpture of broad cords is very similar to that of C. latilirata Rehder 1985 ; C. australis n. sp. differs being more elongated and attaining a larger size. The juveniles are very similar to juveniles of C. bulbiformis (Conrad, 1837) which has not been found at Austral Islands.

A specimen of C. australis n. sp. has been figured by Salvat & Rives (1975: 310, fig. 190 as C. costularis ) supposedly from Fatu Hiva Is. (Marquesas), where in a recent revision based on extensive sampling ( Oliverio 2008a), I have not found it.

Figures

FIG. 3. — A-C, Coralliophila latilirata Rehder,1985;A, paratype (USNM 732294),on top of reef in 15 m, off the barrier reef on the N coast of Tubuai [23°19’S, 149°29W approx. coordinates]; B, C, holotype (USNM 731531), Oeno, Pitcairn Islands; D-H, C. australis n. sp.; D, E, holotype (MNHN 20965), East of Tupuaki Bay, ATELIER RAPA 2002, stn 21, 27°34.2’S, 144°20.6’W, 5 m; F, G, paratype (MNHN 20967), Marotiri Is., BENTHAUS, stn DW 1879, 27°55’S, 143°30.1’W, 52 m; H, paratype (MNHN 20967), Marotiri Is., BENTHAUS, stn DW 1879, 27°55’S, 143°30.1’W, 52 m. Scale bars: A-E, 10 mm; F, G, 5 mm; H, 2 mm.

FIG. 12. — A, Coralliophila australis n. sp., paratype (MNHN 20967), Marotiri Is., BENTHAUS, stn DW 1879, 27°55’S, 143°30.1’W, 52 m; B, C. costularis (Lamarck, 1816), Rimatara Is., BENTHAUS, stn DW 2013, 22°38.6’S, 152°49.7’W, 80-93 m; C, Coralliophila sp. A, Banc Arago, BENTHAUS, stn DW 1970, 23°22’S, 150°43.2’W,350-401 m; D, Babelomurex fusiformis (Martens, 1902), North coast of Rurutu, BENTHAUS, stn DW 1999, 22°25.1’S, 151°22.1’W, 270-500 m; E, Rapa sp. cf. R. incurva (Dunker, 1852), Banc Président Thiers,BENTHAUS,stn DW 1926, 24°38.2’S, 146°00.8’W,50-90 m; F, Babelomurex sibogae (Shepman,1911),Banc Président Thiers, stn DW 1929, 24°38.6’S, 146°01.6’W, 350-370 m. Scale bars: 100 μm.