Epitoniidae Berry, 1910 (1812)

Rectacirsa fregata

(Iredale, 1936)

Description:

Dimensions range from 4 mm - 4 mm high and 1.5 mm wide.
Width to height ratio: 0.38:1 ~ 0.38:1

Shell: stout, ventricose; solid; minute. Exterior colour dirty white. About 9.5 whorls, well rounded, convex; protoconch elongate, slightly tilted, terminating in a vertex with ~3.5 whorls smooth; teleoconch with ~6 whorls. Suture deep. Imperforate: no umbilical chink. Approximately 11 costae on the body whorl. Costae are separated, elevated, do not continue onto the base. Intercostal spaces spirally straiate. Interstices with approximately 10 spiral striae per whorl. Base with a strong keel where the axial ribs terminate. Aperture roundly oval, lip with strong flattened varix.

Rectacirsa fregata [Fig.2a] compared with Cylindriscala distincta [Fig. 2b]. Rectacirsa fregata has a smaller and inclined protoconch, and a microscopically pitted intritacalx. , There are 11 axial ribs on the last whorl while C. distincta has 16.

Distribution:

Sydney, New South Wales, Australia. Known form the holotype and one other specimen [Beechey, 2008]

Habitat:

continental shelf -deep water

Type Material:

Holotype: AMS C.24412 for Rectacirsa fregata (Iredale, 1936) - Locality: off Sydney, New South Wales, 250 fms [= 457 m]. [Brown, L. & Neville, B.D., 2015]

SpeciesImage

Iredale, T. (1936). Plate xxii. Fig. 28.

Distribution

as listed in source literature

Iredale, T. (1936).

Species Image

Plate xxii. Fig. 28.

Species Image

pp: 305.

original description

Kaicher, S.D. (1980).

Species Image

Card #: EP2-3096.

Holotype: Australian Museum C.24412

Beechey, D. (2008).

Species Image

pp: Rectacirsa fregata. Fig. 1.

Off Sydney, 457 m Holotype: C.461150)

Source Literature:

Beechey, D. (2008). Shells NSW -Rectacirsa_fregata. https://seashellsofnsw.org.au/Epitoniidae/Pages/Rectacirsa_fregata.htm [Accessed 11 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. (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]
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