Epitonium christyi

Description:

Dimensions range from 7.4 mm - 21 mm high and 3.2 mm - 8 mm wide.
Width to height ratio: 0.43:1 ~ 0.38:1

Shell: moderately broad, moderately stourt, broadly elongate; thin; small to moderately small. Exterior colour white with a weak brown band centrally and scattered brown spots. About 9 whorls, rounded, Irdeale [1936:298] notes the whorls are not separated, however Beechey [2008] states they are disconnected in the holotype and other specimens, joined only by the costae. Suture very deep. Umbilicate: narrowly chinked, may be closed in some specimens. Approximately 10 - 13 costae on the body whorl. Costae are tall, erect, rather thick. Costae aligned from whorl to whorl; joined across the suture; peaked at the shoulder; relected, slightly reflexed. Intercostal spaces with numerous minute spiral striations which are crossed with finer axial striations. Aperture ovate; peristome complete; outer lip supported by a costa.

This species is close to E. (Hi.) marmoratum, but it can be distinguished by its rather slender shape and not continued axial costae [Nakayama, 2003:61-62]

Distribution:

Australia and Japan. In Australia, known only from Port Stephens and Sydney Harbour. [Beechey, 2008]. In Japan, known from off Minabe, Kii Peninsula, in 70 m [Nakayama, 2003:61].

Habitat:

Known from empty shells from beach wash-up [Beechey, 2008],and down to 70m [Nakayama, 2003:61-62].

Etymology:

.

Type Material:

Holotype: Australian Museum: C.60648 for Epitonium christyi (Iredale, 1936) - Type Locality: Australia, New South Wales, Sydney Harbour (33° 51' 00' S, 151° 14' 00' E) 1928 - 1929, Comtesse, Captain D L(Collector), Dredged.. [Australian Museum, 2026: C.60648]
Paratype: Australian Museum: C.230422 [as Acutiscala christyi Iredale, 1936] - Type Locality: Australia, New South Wales, Sydney Harbour (33° 51' 00' S, 151° 14' 00' E) 1928 - 1929, Comtesse, Captain D L(Collector), Dredged.. [Australian Museum, 2026: C.230422]