The Noduled Littorina has a distribution range restricted to the north-western Western Australia. It ranges from Geraldton to Kimberley (WA).Features:
The Noduled Littorina has a solid shell with a characteristic diamond-shaped outline and a diamond-shaped aperture. It grows to a length of 14 to 20 mm. There are two rows of whitish to reddish-brown nodules over a dark brown base colour on the spire and body whorls. There are four or five flattened body whorls. The often-eroded spire is less than half the length of the shell. The base of the shell is partially flattened, with a row of large, reddish-brown coloured nodules along the edge. The very thin operculum is composed of a translucent horn-like material.
The shells external colour consists of whitish to reddish-brown nodules and very dark brown interspaces. The aperture is dark brown with narrow white band near the hind junction of the outer lip and the columella. White spots occur on the inner edge of the aperture. The columella is usually light brown to light violet in colour.Ecology/Way of Life:
The Noduled Littorina occurs on rocks across all tide levels, up into the splash zone. All Littorinids are algae feeders. Both N. australis and N. nodosa have the same distribution range, live in same habitats, and readily hybridise. The hybrids look like intermediates between the two forms. Rosewater (1970) considers that both forms are valid species, not two forms of the one species.Interaction with Humans/Threats:
Although the range of the Noduled Littorina is very restricted, it is found where human habitation is sparse. However, off-shore oil mining, mineral mining and shipping accidents could prove to be hazardous.Other Comments:
Nodilittorina nodosa, Gray, 1839. Nodilittorina is made up of two Latin words. Nodi comes from the plural of the Latin word nodus, being nodi, and littorina comes from the Latin word littoralis, meaning shore. Nodosa comes from nodose, having nodes, knots or swellings and comes from the Latin word nodus.Further Reading:
Davey, K. (1998) A Photographic Guide to Seashore Life of Australia. p.101, New Holland Press, Sydney.
Rosewater, J.R. (1970). The family Littorinidae in the Indo-Pacific. Part I. The subfamily Littorinidae. Indo-Pacific Mollusca. v.2, 417-506.
Wells, F.E. & Bryce, C.W. (1988). Seashells of Western Australia. p.50, Western Australian Museum.
Wilson, B.R. & Gillett, K. (1979). A Field Guide to Australian Shells: Prosobranch Gastropods. p.50, Reed.
Text, map & photograph by Keith Davey.Sponsorship welcomed:
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