An Indo-west Pacific tropical species, in Australia the Undulated Littorina ranges from North West Cape in WA across northern Australia, including the NT and Qld. to the Wollongong region of NSW (WA, NT, QLD, NSW).Features:
The Undulated Littorina has a thick, turban-shaped shell with five to nine rounded whorls that are sculptured with seven to ten spiral, bevelled ridges. It grows to a length of 20-24 mm. The spire is less than half the shell length. On the body whorl, weaker secondary striations lie between the primary ones. The entire surface is covered with microscopic, closely spaced, wavy spiral threads. The axial sculpture is of regular oblique growth lines, which form a faint reticulated pattern. The base of the shell is not flattened, but is separated from the upper part of the body whorl by a feint ridge at the shells edge called a keel. The aperture is broadly oval in shape and is thickened.
The Undulated Littorina's shell can be quite variable in colour. It may vary from mottled yellowish-grey to banded dark brown with zigzag white flame-like markings above , and is usually solid brown below. The aperture colour varies from light to dark yellowish-brown. The columella is greyish-violet or white, edged with brown. The animal has darker markings on the upper part of the tentacles, snout and foot.Ecology/Way of Life:
It lives between the tides on rocky ocean shores, forming clusters in rock crevices during the daylight hours. It is an active algae grazer at night. The female produces a pelagic egg capsule.Interaction with Humans/Threats:
An Indo-Pacific species, it has a wide range across northern tropical Australia and appears not to be under threat.Other Comments:
Littoraria undulata , Gray, 1839. Melaraphe undulata is a synonym. Littoraria is made up of the Latin word littoralis that means belonging to the seashore, while aria means air.
The name Littoraria refers to members of this genus that are usually found on the seashore in the littoral or intertidal zone. Most species of this genus are usually found above water level, in the air. Some species, with the exception of this one, live on mangrove tree trunks. Undulata comes from the Latin word undulatus or unda, meaning a wave.Further Reading:
Davey, K. (1988). A Photographic Guide to Seashore Life of Australia. New Holland Press. p. 104.
Short, J. W. & Potter, D.G. (1987), Shells of Queensland and the Great Barrier Reef. Golden Press. p. 8.
Wells, F. E. & Bryce, C. W. (1988), Seashells of Western Australia. Western Australian Museum, p.52, plate 10-120.
Wilson, B. (1993) Australian Marine Shells. V.1. p.34.
Wilson, B.R. & Gillett, K. (1971). A field guide to Australian Shells: Prosobranch Gastropods. Reed. P.52.
Text, map & photograph by Keith Davey.Sponsorship welcomed:
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