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ACTEONIDAE |
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Acteon subroseus Iredale, 1936 Description: Shell pupoid in shape, relatively wide, aperture ½ of total shell length. Whorls evenly convex with suture impressed. Last whorl with about 25 flat spiral cords, the intervening grooves with fine axial lamellae. Aperture broadly elongate, increasing from narrow at top to broad and rounded below; outer lip sharp, inner lip with thick white callus on previous whorl. Columella with a single fairly weak plait. Shell pale pink with a white band below suture, fading to white; when fresh, covered with brown periostracum, thickest at top and bottom of whorl. Size: Up to 13 mm in length Distribution:
Endemic to Habitat: Subtidal, 30-400 m. Moderately common. Comparison: The shell of Acteon is wider than that of Pupa, with a simple, not bifid, columellar plait. Remarks: Acteon roseus Hedley, 1906 (Fig. 2) is similar to this species. It is known from only two specimens of confirmed identification – the holotype and one other specimen which was mentioned by Hedley when he described the species. Both differ from A. subroseus by having a wider shell with the umbilicus open. Hedley said that they were collected intertidally, which is in contrast to the habitat of A. subroseus which is always subtidal. It appears to be a different species to A. subroseus, but more specimens are required before a firm decision can be made. Fig.
1: Acteon
subroseus HOLOTYPE 5 miles N off Montague Is., NSW, in 60-70 fathoms
(110–128 m). (C.060703). Fig.
2: Acteon
roseus |
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