|
|
RHIZORIDAE |
|
|
|
Volvulella rostrata (A. Adams, 1850) Description: Shell involute, tall, posterior end rounded, length more than twice width, apex narrow, sides gently convex, becoming straight-sided in large specimens. Surface smooth, sometimes with fine spiral grooves, more prominent on base. Aperture extends whole length of shell, narrow in top half, slightly wider below. Columella narrow, with long thin umbilical slit behind. Shell translucent when fresh, becoming opaque white. Size: Up to 7 mm in length. Distribution: Known from Ballina, NSW, southwards and around southern Australia to southwestern WA, including Tas. Habitat: Beach washup, and down to 128 m. Uncommon. Remarks: The shape changes with maturity, from ovate with convex sides when juvenile (Fig. 1b) to more elongate with parallel sides when mature (Fig. 1a). Fig. 1: a. Off Twofold Bay, NSW, 27-128 m (C.395175). b. 15 miles (24 km) off Twofold Bay, NSW, in 75 m (C.474302). |
|
