Header Image
Epitoniidae Berry, 1910 (1812)

Acrilla acuminata

(G. B. Sowerby II, 1844)

Description:

Dimensions range from 35 mm - 55 mm high and 8.18 mm - 22.28 mm wide.
Width to height ratio: 0.23:1 ~ 0.41:1

Shell: elongated, acuminate; moderately small to medium. Exterior colour pale fulvous, with two brown spiral bands, with white columella. About 18 whorls, convex, anteriorly keeled; protoconch with ~3 whorls ; teleoconch with ~15 whorls. Suture impressed. Imperforate. Approximately 20 - 46 costae on the body whorl. Costae are prosocline, fine, closely spaced, flat topped, slightly sinuous. There are 35 varices on each whorl. Intercostal spaces with exceedingly faint, irregular spiral stiae. Base with basal disc present on body whorl, keeled at periphery. Columella flattened, arched. Aperture round, rather long; outer lip simple, thin. Operculum thin, yellow.


Distribution:

Southern parts of Japan, Taiwan, Philippines to Indonesia [Nakayama, 2003:16]; south to Queensland Australia [Weil et al. 1999: 82]; Korea, Red Sea [Higo et al., 1999:unpaginated]; Gulf of Thailand [Wells FE et al., 2021:127]


Habitat:

10-100 m [Higo et al. 1999: 179]


Etymology:

[latin] from acuminatus = pointed, sharpened, tapering to a point


Type Material:

Syntype: NHMUK 1981038 [as Scalaria acuminata G.B. Sowerby II, 1844] - Type Locality: Malacca. [Brown & Neville, 2015]


SpeciesImage

Murrell (2025).

off Jaiding District, Kaohsiung City, Taiwan.
Trawled by shrimp boats from sand and shell rubble at 120-140m.

Distribution

as listed in source literature

Sowerby, G. B. II. (1844).
Shown in text as Scalaria acuminata G.B. Sowerby II, 1844
Species Image
Plate XXXV. Fig. 130.
Species Image
pp: 106.
93. Sc. ACUMINATA, (pi. XXXV. f. 130.) Sow. Jan. Zool. Proc. 1844.

Original description
Sowerby, G. B. II. (1873).
Species Image
Plate x. Fig. 74a.
Species 74. (Fig. a, b, Mus. Brit.)
Scalaria acuminata
Species Image
Plate x. Fig. 74b.
Species 74. (Fig. a, b, Mus. Brit.)
Scalaria acuminata
Tryon, G.W. (1887).
Shown in text as Scalaria acuminata G. B. Sowerby II, 1844
Species Image
Plate 17. Fig. 35.
Species Image
Plate 17. Fig. 30.
Species Image
pp: 83.
Clessin, S. (1897).
Shown in text as Scalaria acuminata G. B. Sowerby II, 1844
Species Image
Plate 9. Fig. 1.
Species Image
pp: 32.
Shell elongated, imperforate, pointed, pale tawny, with two dark brown spiral bands; whorls fifteen, slightly connected, keeled in front; varices very numerous, densely arranged, elegantly curved; aperture rather long, outer lip thin, columella somewhat flattened, arched.
Thiele, J. (1925).
Shown in text as Scalar (Acrilla) acuminata G. B. Sowerby II, 1844
Species Image
pp: 271.
Scala (Acrilla) acuminata Sow.
Since only the upper nine whorls of one shell are preserved, the identification remains somewhat uncertain. The form, however, is similar to that of the named species. The last preserved whorl bears very numerous ribs (about 35), with smooth spaces between them. As the species was described from Malacca, its occurrence near Padang can be regarded as probable.
Nakayama, T. (2003).
Species Image
pp: 119. Plate 8. Fig. 10-12.
Amaea (Acrilla) acuminata (Sowerby, 1844)
height 38.1 mm; breadth 9.2 mm (KC); fig. 12, base
Robba E, Di Geronimo I, Chaimanee N, Negri MP & Sanfilippo R (2004).
Species Image
pp: 92. Plate 12. Fig. 1.
Figs. 1a, 1b. Amaea (Acrilla) acuminata (Sowerby, 1844), Station TH 98; scale bar 5 mm.
Murrell (2025).
Species Image
off Jaiding District, Kaohsiung City, Taiwan.
Trawled by shrimp boats from sand and shell rubble at 120-140m.

Synonymy:

Scalar (Acrilla) acuminata G. B. Sowerby II, 1844 [in Thiele, J., 1925].
Scalaria acuminata G. B. Sowerby II, 1844 [in Clessin, S., 1897].
Scalaria acuminata G. B. Sowerby II, 1844 [in Tryon, G.W., 1887].
Scalaria acuminata G.B. Sowerby II, 1844 [in Brown, L. & Neville, B.D., 2015].
Scalaria acuminata G.B. Sowerby II, 1844 [in Sowerby, G. B. II., 1844].
Scalaria acuminata G.B. Sowerby II, 1844 [in Sowerby, G. B. II., 1873].
Scalaria subtilis var. laevis Grabau & S. G. King, 1928 [in Coan, E. & Lutaenko, K. & ZHANG, J. & Sun, Q., 2015].


Source Literature:

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]
Coan, E. & Lutaenko, K. & ZHANG, J. & Sun, Q. (2015). The molluscan taxa of A. W. Grabau & S. G. King (1928) and their types. Malacologia. 58(1-2). 10.4002/040.058.0206. [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]
Huang, C. W. & Lee, Y.C. (2016). Checklist of the family Epitoniidae (Mollusca: Gastropoda) in Taiwan with description of a new species and some new records. Biodiversity Data Journal. 4. doi: 10.3897/ BDJ.4.e5653 [Accessed 25 August 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]
LKCNHM-EBOOK-2021-0001 [Accessed 10 February 2026]
Nakayama, T. (2003). A Review of Northwest Pacific Epitoniids. Monographs of Marine Mollusca. 6. Backhuys Publishers
Robba E, Di Geronimo I, Chaimanee N, Negri MP & Sanfilippo R (2004). Holocene and recent shallow soft-bottom mollusks from the northern Gulf of Thailand area: Scaphopoda, Gastropoda, additions to Bivalvia.. La Conchiglia. 35 (Supplement 309)
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). 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]
Thiele, J. (1925). Gastropoden der Deutschen Tiefsee-Expedition. II Teil. Wissenschaftliche Ergebnisse der Deutschen Tiefsee-Expedition auf dem Dampfer "Valdivia" 1898-1899.. 17(2). https://www.deutsche-digitale-bibliothek.de/item/3NJJP6TFO3ZWXZDRTI2CZV66VP76UDWR [Accessed 26 October 2025]
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
Wells, F.E., Sanpanich K., Tan, SK, & Duangdee, T. (2021). The Marine and Estuarine Molluscs of Thailand. Lee Kong Chian Natural History Museum, National University of Singapore,. http://doi.org/10.26107/
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