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Epitoniidae Berry, 1910 (1812)

Epitonium jousseaumei

(de Boury, 1886)

Description:

Dimensions range from 9.3 mm - 14 mm high and 4.8 mm - 7 mm wide.
Width to height ratio: 0.52:1 ~ 0.5:1

Shell: broadly elongate, elongated, turreted; thin; small. Exterior colour white. About 10 whorls, well rounded, disconnected, joined only by costae; rounded, strongly sculptured; protoconch with 1.5-2 whorls polished smooth, white; teleoconch with ~8 whorls rounded, tightly coiled. Spire elongated, turreted. Suture deep, slightly oblique, very deep, and formed by the junction of the longitudinal ribs. Umbilicate, Imperforate: open as a narrow slit where the costae would normally converge and fuse, a single strong costa is formed. Approximately 14 - 16 costae on the body whorl. Costae are thin, flattened between the suture and peak creating tabulate appearance. Costae aligned from whorl to whorl; strongly rolled back except on shoulder, recurved. Intercostal spaces with fine spiral threads crossed by fine, closely packed spiral striae crossed by growth lines forming very fine cancellated sculpture. Base is very slightly flattened around the umbilicus with a moderately thick ridge from the fused ends of the costae. Aperture ovate; peristome complete; outer lip with normal rib externally. Operculum unknown.


Distribution:

off Simoda Izu Peninsula, Japan [Nakayama, 2003:55]; New Caledonia, Port Douglas southwards to Gladstone, Queensland [Beechey, 2008i]; Sydney Harbour, NSW [Iredale, 1936: 296]. Beechey [2008i] suggests the NSW speciemns may be fossils.


Habitat:

to 82m. known mostly from beach shells [Beechey, 2008].


Etymology:

As indicated by the author [Boury, 1886: 13], the species is named after Dr. Jousseaume.


Type Material:

WoRMS currently contains a duplicate record recognising Epitonium heloris (AphiaID 523873) as an accepted species, despite the more recent treatment of Mazescala heloris as a junior synonym of Epitonium jousseaumei (AphiaID 523893).

Holotype: MNHN-IM-2000-4283 [as Crisposcala jousseaumei de Boury, 1886] - Type Locality: New Caledonia. Ducos Peninsula. [Muséum national d'Histoire naturelle, 2026: MNHN-IM-2000-4283]
Holotype: Australian Museum: C.60642 [as Epitonium heloris (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.60642]


SpeciesImage

Iredale, T. (1936). Plate xxii. Fig. 3.

Distribution

as listed in source literature

Boury, E. de (1886).
Shown in text as CRISPOSCALA JOUSSEAUMEI, de Boury,
Species Image
Plate III. Fig. 1.
Greatly magnified specimen, viewed from the front.
Exemplaire trés-grossi, vu de face.
Species Image
pp: 13.
Translation: shell with an umbilical slit, elongated, turreted, white, adorned with longitudinal ribs; spire elongated, turreted, lacking its apex; suture slightly oblique, very deep, and formed by the junction of the longitudinal ribs; 6 1/2 remaining whorls, barely flattened near the suture; they bear thin, irregularly reflected, angular, frizzy, and spiny lamellar longitudinal ribs on their upper part; the last whorl, barely smaller than the rest of the spire, is adorned with 16 lamellae. Its base is very slightly flattened around the umbilicus, where it bears a fairly prominent but moderately thick ridge due to the coiled and fused ends of the longitudinal ribs. The aperture is rounded and rather small; the peristome is slightly doubled; the internal part is continuous, forming a folded sheet over the columella; the external peristome is reflected, fairly thin, and externally formed by the last lamella. It thins towards the columella, over which it folds.
Species Image
pp: 14.
Iredale, T. (1936).
Shown in text as Mazescala heloris Iredale, 1936
Species Image
Plate xxii. Fig. 3.
Species Image
pp: 296. Plate xxii.
original description
Beechey, D. (2008i).
Shown in text as Mazescala heloris Iredale, 1936
Species Image
pp: Epitonium jousseaumei. Fig. 1.
Holotype: of Mazescala heloris. Sydney Harbour, dredge Triton (C.060642)
Muséum national d'Histoire naturelle (2026).
Shown in text as Crisposcala jousseaumei de Boury, 1886
Species Image
Crisposcala jousseaumei de Boury, 1886
Holotype: MNHN-IM-2000-4283
"Nouvelle-Caledonie. Presquile Ducos !"
Credit: MNHN - Brabant D. - 2005
CC BY-NC-ND 4.0
Australian Museum (2026).
Shown in text as Mazescala heloris Iredale, 1936
Species Image
Fig. C.60642.
Epitonium heloris (Iredale, 1936)
Holotype: C.60642
Australia, New South Wales, Sydney Harbour (33° Australia, New South Wales, Sydney Harbour (33° 51' 00" S, 151° 14' 00" E) 1928 - 1929, Comtesse, Captain D L(Collector), Dredged.
Australian Museum. Photograph: M. Allen.
Copyright Australian Museum. Released under Creative Commons Licence CC BY-NC 4.0.

Synonymy:

Crisposcala jousseaumei de Boury, 1886 [Boury, 1886: 13; Muséum national d'Histoire naturelle, 2026: MNHN-IM-2000-4283]
Epitonium (Laeviscala) heloris (Iredale, 1936) [Nakayama, 2003: 55]
Epitonium heloris (Iredale, 1936) [Kaicher, 1981: EP2-3029; WoRMS Editorial Board, 2025: 523893; Hutchings et al., 2013: 297; Australian Museum, 2026: C.60642]
Mazescala heloris Iredale, 1936 [Beechey, 2008i; Iredale, 1936: 296; Brown & Neville, 2015: 83; Australian Museum, 2026: C.60642]


Source Literature:

Australian Museum (2026). Australian Museum provider for OZCAM. Occurrence dataset. Atlas of Living Australia. https://doi.org/10.15468/e7susi accessed via GBIF.org [Accessed 18 July 2026]
Beechey, D. (2008i). Epitonium_jousseaumei. Seashells of NSW. https://seashellsofnsw.org.au/Epitoniidae/Pages/Epitonium_jousseaumei.htm [Accessed 9 May 2023]
Boury, E. de (1886). Monographie des Scalidae vivants et fossiles. Partie I: Sous genre Crisposcala.. Monographie des Scalidae vivants et fossiles. 1. Comptoir Géologique de Paris. https://archive.org/details/monographiedess00bourgoog [Accessed 14 March 2025]
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]
Hutchings, P. & Ahyong, S. & Ashcroft, M. & Mcgrouther, Mark & Reid, A. (2013). Sydney Harbour: its diverse biodiversity. Australian Zoologist. 36. http://dx.doi.org/10.7882/AZ.2012.031 [Accessed 28 February 2026]
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. (1981). Epitoniidae II [Pack 30]. S. D. Kaicher, St. Petersburg, Florida. http://www.femorale.com/kaicher/species.asp?f=Epitoniidae&c=125 [Accessed 8 May 2023]
Kaicher, S.D. (1983). Epitoniidae III [Pack 35]. S. D. Kaicher, St. Petersburg, Florida. http://www.femorale.com/kaicher/species.asp?f=Epitoniidae&c=125 [Accessed 8 May 2023]
Muséum national d'Histoire naturelle (2026). Mollusca (IM) collection. Muséum national d'Histoire naturelle. https://science.mnhn.fr/institution/mnhn/collection/im/item/search [Accessed 18 July 2026]
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
WoRMS Editorial Board (2025). World Register of Marine Species. https://www.marinespecies.org at VLIZ. [Accessed 8 November 2025]

WoRMS direct page link: Open WoRMS record