Epitoniidae Berry, 1910 (1812)

Epitonium irregulare

(Sowerby II, 1844)

Description:

Dimensions range from 6 mm - 30.8 mm high and 3.5 mm - 11.2 mm wide.
Width to height ratio: 0.58:1 ~ 0.36:1

Shell: ventricose, pointed, pyramidal; thin fragile; minute to moderately small. Exterior colour white. About 12 whorls, rounded, contiguous; protoconch with ~3 whorls usually missing in adult specimens; teleoconch with 9 whorls rounded, increasing gradually. Spire pyramidally elevated. Suture deep and slightly fenestrated, channelled near the suture. Umbilicate: narrow, distinctly perforated, partly covered by the reflected columellar margin. Approximately 38 costae on the body whorl. Costae are very thin, numerous, irregular. Costae aligned; slightly coronated at the shoulder; standing out slightly at the suture; contiguous, contiguous across the whorls. Intercostal spaces crossed by minute spiral striae. Columella thin, sinuous. Aperture sub-ovate; peristome thin, complete; outer lip margin roundly arcuate; inner lip oblique.

Distribution:

Southern Japan; Philippines, Vanuatu. Brazier [1875] also reported specimens from Torres Strait

Habitat:

reported from mushroom coral, 3-15 m

Type Material:

Catanauan, pr. Tayabas, Luzon Island, Philippines for Epitonium irregulare (Sowerby II, 1844). [Nakayama, T., 2003]
Off Esuzaki, Kii Peninsula, Japan, at about 150 m deep [as Epitonium virgo (Masahito & Habe, 1976)]. [Nakayama, T., 2003]
NHMUK 1966402 (syntypes). [as Scalaria irregularis G.B. Sowerby II, 1844:] - Locality: Catanuan, Luzon, Philippines.. [Brown, L. & Neville, B.D., 2015]
not located. [as Scalaria undulatissima G.B. Sowerby II, 1874:] - Locality: none given.. [Brown, L. & Neville, B.D., 2015]
Holotype : NSMIT-Mo 52446 [as Foliaceiscala virgo Masahito & T. Habe, 1976] - Locality: off Esuzaki (cape), Wakayama prefecture (Kii peninsula, central Honsh

SpeciesImage

Murrell, T. (2023).

Mactan Island, Cebu, Philippines
on mushroom coral at 3-5 m
30.8mm

Distribution

as listed in source literature

Sowerby, G. B. II. (1873-1874).

Shown in text as Scalaria irregularis

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Plate xxxiii. Fig. 40.

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Plate xxxiii. Fig. 60.

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pp: 90.

Sowerby, G. B. II. (1873-1874).

Shown in text as Scalaria irregularis G. B. Sowerby II, 1844

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Plate iv. Fig. 26.

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Shell white, thin, umbilicate, pyramidal; whorls rounded, contiguous; varices very slender, numerous, irregular, slightly projecting at the suture; inner lip oblique.

Sowerby, G. B. II. (1873-1874).

Shown in text as Scalaria undulatissima G. B. Sowerby II, 1874

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Plate xiv. Fig. 121a.

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Plate xiv. Fig. 121ab.

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Tryon, G.W. (1879).

Shown in text as Scalaria undulatissima G. B. Sowerby II, 1874

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Plate 12. Fig. 70.

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pp: 60.

Tryon, G.W. (1879).

Shown in text as Scalaria irregularis G. B. Sowerby II, 1844

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Plate 12. Fig. 71.

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pp: 60.

Clessin, S. (1897).

Shown in text as Scalaria undulatissima G. B. Sowerby II, 1874

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Plate 7. Fig. 4.

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pp: 26-27.

Shell white, thin, pyramidal, perforated, spirally very finely striated; approximately nine whorls increasing rather rapidly, canaliculated at the suture; varices unequal, thin, only rarely thicker, neatly undulate, aculeate (spiny) near the suture; umbilicus small; aperture subovate, columellar margin thin and sinuate, outer margin crenulated above, aculeate near the suture.

Clessin, S. (1897).

Shown in text as Scalaria irregularis G. B. Sowerby II, 1844

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Plate 9. Fig. 9.

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pp: 33.

Shell white, thin, umbilicated, pyramidal; whorls rounded, contiguous; varices extremely delicate, numerous, irregular, slightly projecting at the suture; inner lip oblique.

Kaicher, S.D. (1980).

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Card #: EP1-2310.

BMNH type collection 1966402

Nakayama, T. (2003).

Shown in text as Epitonium virgo (Masahito & Habe, 1976)

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pp: 139. Plate 18. Fig. 14-16.

figs 14-16:
Epitonium (Limiscala) virgo (Masahito & Habe, 1976)
height 22.0 mm; breadth 11.2 m (holotype); fig. 16, base

Nakayama, T. (2003).

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pp: 139187-9.

figs 7-9:
Epitonium (Papyriscala) irregulare (Sowerby, 1844)
height 6.0 mm; breadth 3.5 m (KC); fig. 9, base

Kokshoorn, B., Gittenberger, J. & Gittenberger, A (2007).

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pp: 39. Fig. 17-18.

17-18,E.irregulare
(Sowerby[II],1844),syntypes(BMNH1966402),resp.H=12.3mm andH=9.5mm.

Murrell, T. (2023).

Species Image

Mactan Island, Cebu, Philippines
on mushroom coral at 3-5 m
30.8mm

Species Image

Synonymy:

Epitonium virgo (Masahito & Habe, 1976) [in Nakayama, T., 2003].
Foliaceiscala virgo Masahito & T. Habe, 1976 [in Higo, S., Callomon, P. & Goto, Y., 1999].
Foliaceiscala virgo Masahito & T. Habe, 1976 [in Higo, S., Callomon, P. & Goto, Y., 2001].
Scalaria irregularis [in Sowerby, G. B. II., 1844].
Scalaria irregularis G. B. Sowerby II, 1844 [in Clessin, S., 1897].
Scalaria irregularis G. B. Sowerby II, 1844 [in Sowerby, G. B. II., 1873-1874].
Scalaria irregularis G. B. Sowerby II, 1844 [in Tryon, G.W., 1887].
Scalaria irregularis G.B. Sowerby II, 1844: [in Brown, L. & Neville, B.D., 2015].
Scalaria undulatissima G. B. Sowerby II, 1874 [in Clessin, S., 1897].
Scalaria undulatissima G. B. Sowerby II, 1874 [in Sowerby, G. B. II., 1873-1874].
Scalaria undulatissima G. B. Sowerby II, 1874 [in Tryon, G.W., 1887].
Scalaria undulatissima G.B. Sowerby II, 1874: [in Brown, L. & Neville, B.D., 2015].

Source Literature:

Brazier, J. (1875). Shells collected during the Chevert Expedition, with Descriptions of the New Species. Proceedings of the Linnean Society of New South Wales. 1(3). Linnean Society of New South Wales.. https://www.biodiversitylibrary.org/item/22887 [Accessed 3 September 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]
Clessin, S. (1897). Die Familie der Scalariidae. In W. Kobelt (Ed.), Systematisches Conchylien-Cabinet von Martini und Chemnitz. Neu herausgegeben und vervollständigt. 2(13). Bauer & Raspe, NürnbergBauer & Raspe, Nürnberg. https://www.biodiversitylibrary.org/page/34259905 [Accessed 21 June 2025]
Higo, S., Callomon, P. & Goto, Y. (1999). Catalogue and Bibliography of the Marine Shell-Bearing Mollusca of Japan.. https://www.researchgate.net/publication/266375656_Catalogue_and_Bibliography_of_the_Marine_Shell-Bearing_Mollusca_of_Japan [Accessed 25 July 2025]
Higo, S., Callomon, P. & Goto, Y. (2001). Catalogue and Bibliography of the Marine Shell-Bearing Molluscs of Japan. Type Figures. Elle Scientific Publications
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]
Kokshoorn, B., Gittenberger, J. & Gittenberger, A (2007). Epitoniid parasites (Gastropoda, Caenogastropoda, Epitoniidae) and their host sea anemones (Cnidaria,Actiniaria,Ceriantharia) in the Spermonde archipelago, Sulawesi, Indonesia. Basteria. 71(1-3)
Nakayama, T. (2003). A Review of Northwest Pacific Epitoniids. Monographs of Marine Mollusca. 6. Backhuys Publishers
Sowerby, G. B. II. (1844). Monograph of the genus Scalaria.. Thesaurus conchyliorum, or monographs of genera of shells.. 1 (4). London, privately published.. http://biodiversitylibrary.org/page/11076419 [Accessed 22 June 2023]
Sowerby, G. B. II. (1873-1874). Monograph of the genus Scalaria. Conchologia iconica, or illustrations of the shells of molluscous animals, vol. 19, pls 1-16 and unpaginated text.. 19. London. https://www.biodiversitylibrary.org/page/8217819 [Accessed 24 August 2023]
Tryon, G.W. (1887). Manual of conchology, structural and systematic with illustrations of the species. IX. Academy of Natural Sciences. https://www.biodiversitylibrary.org/page/11026889 [Accessed 20 September 2025]
Weil, A., Brown, L. & Neville, B. (1999). The Wentletrap Book. Evolver
WoRMS Editorial Board (2025). World Register of Marine Species. https://www.marinespecies.org [Accessed 8 November 2025]

WoRMS direct page link: Open WoRMS record