Four species of whelks can be found in northeast Florida. These include
Busycon carica (Gmelin, 1791) [Knobbed Whelk],
Busycon perversum
(Linnaeus, 1758) [Lightning Whelk], Busycotypus canaliculatus
(Linnaeus, 1758) [Channeled Whelk], and
Fulguropsis
spirata (Lamarck,
1816) [Pear Whelk]. Of the four, the Lightning Whelk is by far the most
common while the Pear Whelk is uncommon to rare. All four can be found
living intertidally on the open Atlantic Beaches as well as in more
sheltered habitats such as inlets and sounds. |
In the case of the Channeled
and Pear Whelks, the old saying "When you've seen one you've seen them
all" is appropriate for both species. As a rule neither species varies
much in shape and coloration and the shell you find on the beach will look
like the picture in your favorite shell book. However, for a reason
not yet explained, the Channeled Whelk will periodically produce a pure
white shell even though the coloration of the animal and its operculum is
indistinguishable from one which produced a normal shell. Most shell
collectors (as well as this web site) call these specimens "albinos."
Personal observations since 1998 suggest that about 13% of the sub-adult
Channeled Whelks on Duval County beaches have pure white shells. The
species is usually not found in sufficiently large numbers to perform
meaningful scientific studies. However on 9/23/2000, five of 38 specimens
found and examined at Mayport Naval Station Beach in Duval County had pure
white shells. [See Image] Subsequent
finds/observations over the ensuing five years seem to confirm that
approximate ratio.
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Both the Knobbed Whelk and
Lightning Whelk are extremely variable species. The shells of each
individual species differ considerably in shape, spire height, siphonal
canal length, coloration, weight, size and number of knobs/spines, etc.
Fortunately, species identification 99.9% of the time is assured owing to
the fact that the Knobbed Whelk is dextral (right handed - opening to the
right when held with the spire up) while the Lightning Whelk is sinistral
(left handed - opening to the left when held with the spire up). However,
both species on rare occasions are known to produce reverse coiled
specimens (a shell eagerly sought by collectors and both known from
northeast Florida) which can complicate easy identification in some
instances. Ultimately when everything else has proved inconclusive, if the
color of the animal is known, it can provide the "ace in the hole."
The animal of the Knobbed Whelk is light cream colored while the animal of
the Lightning Whelk is black/dark gray [See Live
Animal Images Of All Four Whelk Species Below]. This difference in coloration
proved helpful in determining that a specimen recently found in Duval
County was in fact a reverse coiled (right handed) Lightning Whelk instead
of an abnormal Knobbed Whelk. [See Image]
While talking about the color of whelk animals, one might
logically inquire whether there are whelks with
normally colored shells that have albinistic animals since it known that a
normally colored animal can produce a while shell. Two
observations, five years apart, would seem to indicate that the answer is "maybe." [See
Image1 &
See
Image2] |