Eroded Nerite (Fragment), bleached Black Nerite fragment
Phylum: Mollusca, Class: Gastropoda, Order: Cycloneritida, Family: Neritidae, Genus: Nerita, Species: Nerita atramentosa · Neritidae (Nerite family) · Gastropod (snail/univalve) fragment; specifically an eroded body whorl and columellar section.
Species
Nerita atramentosa (likely species based on Brisbane locality)
Shell Type
Gastropod (snail/univalve) fragment; specifically an eroded body whorl and columellar section.
Family
Neritidae (Nerite family)
Size
Approximately 10-15mm (0.4-0.6 inches). This is a partial remains of a shell that typically reaches 20-30mm in maturity.
Color & Pattern
Pale greyish-white to light lime-green hue. This is not the living color; it is a heavily sun-bleached and water-worn state. The original black or dark grey pigment has been almost entirely leached by UV exposure and saltwater erosion.
Rarity
Very Common. This is one of the most ubiquitous gastropods found on Brisbane beaches like Sandgate and Brighton.
Habitat
Found in the intertidal zone, specifically on rocky shores, jetties, and stone walls. They are marine gastropods that prefer the high-tide mark to stay moist but exposed to air.
Geographic Range
Common along the coastlines of Australia (particularly Southern and Eastern Australia) and New Zealand.
Description
A very worn, beach-rolled fragment of a Nerite shell. The specimen shows a stony, calcified texture with fine pitting and pockmarks caused by seawater erosion. The characteristic 'D-shaped' aperture is vaguely visible but heavily damaged, and the typical spiral sculpture has been smoothed away.
Key Features
Globose (rounded) shape remains visible even in fragment form; the thickened columellar area (the 'deck') is the most durable part of the shell and is what has survived here.
Collector Value
Minimal to none. As a weathered fragment of a very common species, it holds educational value but no significant monetary or aesthetic value for serious collectors.
Condition Notes
Poor / Beach-worn. This is a sub-fossilized or heavily weathered fragment. It lacks the operculum, original color, and structural integrity. Collectibility Grade: Poor.
Interesting Facts
Living Nerites have a 'trapdoor' called an operculum that fits perfectly into their D-shaped opening to seal in moisture, allowing them to survive hours out of water during low tide.
Ecological Role
As a grazer, it plays a vital role in controlling algae growth on rocky substrates within the intertidal ecosystem. It is a food source for predatory snails and shorebirds.
Similar Species
Nerita albicilla (Ox-palate Nerite) which has more bumps on the columella, or Nerita plicata which has deeper ridges.
Beach Finding Tips
Look among the basalt rocks or stone sea walls at Sandgate during low tide. You will find thousands of live, black specimens clinging to the rocks; the white 'skeletons' like this one accumulate in the shell grit nearby.
Notes
Brighton Sandgate beach brisbane