Sea butterfly
A sea butterfly is a small marine snail that swims using wing-like extensions and has a delicate coiled shell.
Also known as: thecosome pteropod, Limacina helicina
How big is it?
5 mm · defined shell height
Also 0.1969 in
Defined shell height · defined specimen
Typical recorded range: 3 mm to 8 mm.
A little perspective
Sea butterfly vs Small ant: length comparison
The shell height of a sea butterfly is approximately equal to the length of a small ant.
A sea butterfly is a small marine snail that swims using wing-like extensions and has a delicate coiled shell.
An ant is a social insect that lives in an organised colony, usually with workers, a queen and specialised roles.
Both rulers start at the same zero and share one linear scale. Artwork keeps its original proportions. Horizontal rulers compare the selected spans; vertical brackets also identify height on the artwork.
Measurements, assumptions & sources +
Sea butterfly
Defined shell height: 5 mm; defined specimen; range 3 mm–8 mm.
A defined 5 mm shelled sea butterfly, modelled on Limacina helicina. The calibrated height follows the shell; wing-like parapodia extend beyond it and posture varies while swimming.
Defined examples — our methodology
The marked defined shell height is calibrated. Unmeasured illustration details are representative.
Small ant
Length: 5 mm; example.
Example 5 mm ant, 3 mg; ants span a wide range of sizes.
Defined examples — our methodology
The marked length is calibrated. Unmeasured illustration details are representative.
Use the visual comparison to explore its scale, then check the measurements and sources.
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Why this measurement?
Why we use 5 mm
We compare the shell height of a sea butterfly. This is an illustrative comparison value, not a claim that every example is the same. The recorded range is 3 mm to 8 mm.
A defined 5 mm shelled sea butterfly, modelled on Limacina helicina. The calibrated height follows the shell; wing-like parapodia extend beyond it and posture varies while swimming.
The marked vertical span follows the measured feature, not the edges of the image. How calibrated comparisons work →
Recorded properties
Dimensions and measurements
| Property | Selected value | Recorded range | Basis |
|---|---|---|---|
| 5 mm | 3 mm to 8 mm | defined specimen |
Around this scale
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Want to check the number?
The source records and measurement method remain available for inspection.
There’s always another scale
Follow your curiosity.
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