_______________
Additional Photos
striae
shell
|
Murchisonella columna
(Hedley, 1907)
Maximum size:
2.4 mm shell length.
Identification:
The
shell of this species is slender with a spiral keel
defining the upper third of each whorl. Fine spiral
striae are confined to the area below the keel and
there is a deep subsutural sinus. Live animals are
cream with the black digestive gland showing through
the apical whorls. The front of the head is lined
with vibrissi.
Natural history:
Shells
of Murchisonella
columna are rare in beach drift but
moderately common in subtidal sand samples to at
least 52 m (170 ft). Live animals are occasionally
found in shallow rocky habitats. It appears to
be a detritus feeder, beating its vibrissi against
the substrate as it crawls.
Distribution:
Maui
and Midway: widespread in the Indo-Pacific;
introduced into the Mediterranean.
Taxonomic notes:
A
photo of a similar shell (from Turkey) on line at
the Natural
History Museum of Rotterdam is labeled Murchisonella columna
(Hedley, 1907) but placed in the Cimidae. Most other
sources consider Murchisonella
as the type genus of Murchisonellidae.
Photo:
CP: Kaanapali (canoe club beach), Maui; Oct. 13,
2007.
Observations and
comments:
Note 1:
( )
|
|
