(Jeffreys, 1867)
Description
Veliger larva with a sinistral shell that is reddish brown in colour and not very transparent (see overview picture). Spire becoming elongated. The embryonic whorls are beset with minute tubercles in a reticulate pattern. The larval whorls have regular orthocline ribs and two pronounced spiral ridges; the adapical ridge originates on the second whorl and the adapical ridge originates on the fourth whorl. Pronounced beak; siphonal canal very wide.
The late larva has a third spiral ridge on the fifth body whorl, this whorl is paler in colour.
The velum is bilobed and always colourless; the left lobe is larger than the right.
Foot is colourless; the mesopodium remains small and is pointed posteriorly; propodial region becomes long and mobileby the three-and-a-half whorl stage.
Adult with a sinistral, glossy and solid shell with a tall, cyrtoconoid spire and a small aperture with a basal siphonal notch [C.pallescens ].
Remark
C. pallescens and Marshallora adversa (Montagu, 1803) are the two gastropod species in the area with a left-coiled shell.
Habitat of adult
Lives on and in sponges, especially Hymeniacidon and Halichondria; may also be found under stones or on algae. Depth range from near LWST to about 100 m deep.
Distribution of adult:
From Spain to Norway and penetrates the Baltic as far as Kiel.