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OMALOGYRIDAE |
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Ammonicera sucina (Laseron, 1954) Description: Shell minute, almost planar, spire sunken. Protoconch plus teleoconch up to 3 whorls. Whorls circular in cross section, wiith growth lines encircling whorls, these usually developing into regular ridges; suture deep. Ventral surface of shell of similar shape and sculpture to dorsal surface. Aperture circular, lip expanded in mature shells. Shell translucent golden-brown, margin of aperture sometimes white in mature shells. Size: Up to 0.7 mm diameter. Distribution: The Australian Museum collection holds specimens from Minnie Waters, near Grafton, NSW, southwards to Ulladulla, NSW. Habitat: Found live on algae in rock pools, North Harbour (Laseron, 1954) Comparison: Ammonicera aura has a wide periphery with spiral cords at top and bottom. Ammonicera sucina and Omalogyra lilliputa are similar, both having whorls circular in cross section. O. lilliputa is the smaller, is dark brown, with the whorls more loosely coiled, and has a smooth shell apart from growth lines. A. sucina is golden brown rather than dark brown, has the whorls more tightly coiled so the last whorl is not so expanded, and the shell has encircling growth lines that develop into strong ridges. Remarks: Ponder & de Keyzer (1998) gave an SEM photo of one view of the shell of this species, and a drawing of the live animal. Although the shells of Ammonicera sucina and Omalogyra liliputia are similar, the animals differ substantially, hence the allocation to different genera. Figs. 1–3: S. side of Ulladulla, NSW. On coralline algae (C.279936). |
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