Epitoniidae Berry, 1910 (1812)

Epitonium christyi

(Iredale, 1936)

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) 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; peaked at the shoulder; relected, slightly reflexed; joined across the suture. 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.

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 washup and down to 70m

Type Material:

Holotype: AMS C60649 for Epitonium christyi (Iredale, 1936) - Type Locality: Sydney Harbour, New South Wales.. [Brown, L. & Neville, B.D., 2015]

SpeciesImage

Iredale, T. (1936). Plate xxii. Fig. 10.

Distribution

as listed in source literature

Iredale, T. (1936).

Shown in text as Acutiscala cruistyi, sp. novo

Species Image

Plate xxii. Fig. 10.

Kaicher, S.D. (1980).

Species Image

Holotype: Australian Museum C. 60649

Wilson, B.R. (1993).

Species Image

pp: 379. Plate 44. Fig. 27.

Beechey, D. (2008).

Species Image

pp: Epitonium christyi. Fig. 1.

Holotype: Sydney Harbour, dredge Triton (C.060648)

Species Image

pp: Epitonium christyi. Fig. 2.

Holotype: Detail of sculpture and suture

Synonymy:

Acutiscala cruistyi, sp. novo [in Iredale, T., 1936].

Source Literature:

Beechey, D. (2008). Shells NSW -Epitonium_christyi. https://seashellsofnsw.org.au/Epitoniidae/Pages/Epitonium_christyi.htm [Accessed 9 May 2023]
Brown, L. & Neville, B.D. (2015). Catalog of the recent taxa of the families Epitoniidae and Nystiellidae (Mollusca: Gastropoda) with a bibliography of the descriptive and systematic literature. Zootaxa. 3907(1). Magnolia Press Auckland, New Zealand. http://dx.doi.org/10.11646/zootaxa.3907.1.1 [Accessed 22 October 2023]
Iredale, T. (1936). Australian molluscan notes. No. 2.. Records of the Australian Museum. 19(5). Australian Museum, Sydney. doi:10.3853/j.0067-1975.19.1936.704 [Accessed 14 September 2023]
Kaicher, S.D. (1980). Epitoniidae I [Pack 23]. S. D. Kaicher, St. Petersburg, Florida. http://www.femorale.com/kaicher/species.asp?f=Epitoniidae&c=125 [Accessed 8 May 2023]
Nakayama, T. (2003). A Review of Northwest Pacific Epitoniids. Monographs of Marine Mollusca. 6. Backhuys Publishers
Weil, A., Brown, L. & Neville, B. (1999). The Wentletrap Book. Evolver
Wilson, B.R. (1993). Australian Marine Shells. Australian Marine Shells. 1. Odessey Publications
WoRMS Editorial Board (2025). World Register of Marine Species. https://www.marinespecies.org [Accessed 8 November 2025]

WoRMS direct page link: Open WoRMS record