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IDENTIFICATION OF THE CYSTISCIDAE AND
MARGINELLIDAE FOUND ON SYDNEY BEACHES
The species tabulated below are recorded in the
Australian Museum collection as being beach collected.
The remaining members of the family occur in sufficiently deep
water to not be washed up on beaches.
The diagnostic features used here are only diagnostic within this
group of species, not within the Cystiscidae and Marginellidae as a
whole, and they need to be used in conjunction with the descriptions and
photographs of the individual species.
For an explanation of the terminology, see the introductions to
Cystiscidae and Marginellidae.
Family
Cystiscidae
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Shells less than 4 mm in length
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No margin on outside of outer lip, except in one species
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At least four plaits on the columella, upper ones often
weak or absent
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Species
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Diagnostic
features
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Adult
size
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Beach
occurrence
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Cystiscus
angasi
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Most common of the NSW cystiscid species; up
to 8 plaits/lirae on the columella
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2 - 3 mm
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Common
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Cystiscus
subauriculata
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Broad, lip flared; 5-7 plaits/lirae on the
columella
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1.5 – 2 mm
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Uncommon
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Gibberula
subbulbosa
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Lirate inside outer lip; lirae extend deep
into aperture. Columella
with 5-7 plaits/lirae
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2.5 - 4 mm
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Common
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Granulina
nympha
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Egg shaped; the only cystiscid with an
external varix.
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1.3 – 2 mm
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Common
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Pugnus
parvus
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Cylindrical shape, dense spiral threads
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1.5 - 2 mm
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Very uncommon
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Family
Marginellidae
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Species
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Diagnostic
features
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Adult
size
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Beach
Occurrence
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Serrata
mustelina
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Elongate, brown bands
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7 mm
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Uncommon
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Alaginella
ochracea
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Distinctive biconic shape
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3 - 4 mm
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Moderately common
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Austroginella
muscaria
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Largest marginellid species in NSW.
The only species over 10 mm in length.
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10 -16 mm
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Common
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Austroginella
johnstoni
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Very similar to A.
muscaria, separated mainly on size.
Base heavily calloused.
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6 - 9 mm
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Common, sometimes abundant
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Austroginella
tasmanica
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More elongate and higher spire than A. muscaria and A. johnstoni
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7 - 10 mm
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Common
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Mesoginella
turbinata
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Usually ribs on dorsum
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5 - 10 mm
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Common to abundant
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Mesoginella
olivella
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Narrower than M.
turbinata, but very variable.
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5 - 10 mm
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Moderately common
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Mesoginella
translucida
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Taller spire than other Mesoginella species; may be quite like Austroginella johnstoni, but distinguished by lip shape.
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5 - 8 mm
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Common to abundant
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Mesoginella
victoriae
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Strongly constricted at base, elliptical in
outline.
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3.8 – 5 mm
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Uncommon
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Mesoginella
strangei
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Distinguished by size; more slender than A.
ochracea
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2.5 – 3.5 mm
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Uncommon
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Ovaginella
ovulum
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Egg shaped, variable in size
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5.5 – 10 mm
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Very uncommon
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