Cuthona sp. #19
|Maximum size: 1.7 mm.
is a tiny, cream species with mottled rust-red pigment on the
bases of the cerata.
The single known Cuthona sp. #19 was found on a
crematus collected in a sand sample taken from a depth of 12-16
m (39-52 ft) in a Halimeda kanaloana
bed. It was observed feeding on the hydroid (presumably a hydractiniid)
held. (Note 1) It was never observed to leave
shell but moved to the apex of the shell when the snail burrowed. (see photos) When resting, it flattened
itself out in the channel formed by the suture. When prodded, it
"flared" its cerata and/or attempted to retreat beneath the sand
surrounding the shell without leaving the shell's surface.
recorded in Hawaii from Black Rock, Maui by CP on April 15, 2005.
1.7 mm; on Nassarius crematus:
Rock, Maui; April 15, 2005.
Observations and comments:
1: Two Nassarius crematus were collected
in a sand sample on April 15, 2005. At the time of collection, it was
noted that one of the shells had much better developed hydroids than
the other. The latter animal was photographed and both were held in a
dish with sand. On the 18th, additional photos were taken that showed
little difference in the hydroid. The Cuthona
was first noticed on April 23 and additional photos were taken on the
24th showing the greatly reduced hydroids. Subsequently, feeding on the
hydroids was observed under the microscope. Perhaps, the Cuthona came in on the snail that
already had reduced hydroids, then transfered to the snail with intact
hydroids in the close proximity of the holding dish?