Written by Mark Heckman, Educator, Waikiki Aquarium/ University
of Hawai'i - Manoa
is a great joy in discovery. We all feel it. Whether it
is the discovery of a new idea, a new invention, or a new
organism, humans are always in quest of the new and unknown.
In biology, the discovery of a new species (1)
is one such event. A scientist that identifies a new type
of animal not only gets to name it, but gets their name
listed with it as well. Thus the Blackspot Sergeant Major
fish's scientific name is Abudefduf soridus (Forsskal, 1775).
This fish was described ("discovered") by Forsskal
in 1775 and he had the honor to name it (Journal:
most major groups of fish and other vertebrates have largely
been discovered at this point in history. This leaves, at
first glance, little for the current and future generations
to do. But wait; is the world really all about the vertebrates?
Those animals that possess a backbone (a bony sheath of
vertebrae) and most resemble us? Perhaps not, the vertebrate
line includes only five percent of the animal life on Earth.
Many of the most wondrous animals on this planet are loosely
termed the "invertebrates". These are the animals
without backbones, the animals that are "not us",
the animals that are perhaps the most interesting and beautiful
better for current and future discoverers and biologists,
the "invertebrates" are tremendously understudied,
unnamed and unknown. Here then is today's tale - of a simple
invertebrate, a shrimp, that through the circuitous path
that science often takes, may yet be a new species just
are part of the group Arthropoda (arthro, from the Greek
= joint and pod = foot or jointed foot animals). This impressively
successful group has an external skeleton that is articulated
(jointed). This allows these armored creatures to use leverage
across the joints to hoist themselves up and go into virtually
all environments in the world (2). Arthropods
comprise over eighty five percent of all known animal species,
with many more yet to be described.
1999, a young dive master and marine photographer, Keoki
heard from friends at the University of Hawai`i about a
job running a dive operation at remote Midway Atoll National
Wildlife Refuge. He and his wife had wanted to vacation
on Midway, but the cost was too much. Here was a chance
to spend months on Midway and get paid for it as well -
low pay and hard work, but pay nonetheless. Keoki and Yuko
took the job and began photographing the rare and unusual
marine life they encountered.
shrimps of interest to this story were not initially one
of those animals. Part of the genus Rhynchocinetes
(rhine ko sin e teas), these shrimp hide during the day
and only come out at night when they are safe from marauding
predatory fish. Home aquarists sometimes call them dancing
shrimps for the delicate movements of their legs. Like many
of their secretive kin, they can be spectacularly colored
and patterned - elegant designs that few humans will ever
this particular population of Rhynchocinetes shrimp
at Midway Atoll was not found at the beautiful dive sites
well visited by the local SCUBA crowd. They were found in
an area of desolate-looking pocked brown reef surrounded
by sand. Not an area that divers or snorkelers would normally
a bit of chance; some of this reef was just offshore the
one open beach at Midway. During a day off, a well-known
dive operator from Kona, Hawai'i noticed an unusual fish
on this patch of reef while snorkeling. She asked Keoki
to go out and identify the fish (those charismatic vertebrates
get all the attention). The fish turned out to be reasonably
common. Keoki identified it at a glance, and then happened
to look beneath the fish in the urchin-filled holes. Small
elegantly ornamented shrimp filled the holes as well. He
took a photo.
shrimp were not ones Keoki knew, so he posted the picture
on his website
and waited. About this same time, a science librarian and
marine photographer (3) on Oahu, Hawai`i,
had just finished a book on local marine invertebrates (4).
The image came to his attention, he didn't recognize it,
so he sent it on to a world expert on crustaceans (including
shrimp), Junji Okuno in Japan. Junji also didn't recognize
the beautiful little specimens, though they looked close
to a species found in Japan. He wrote to Keoki expressing
a wish for more photos and a specimen. The shrimp proved
elusive and very difficult to catch.
was in 1999. The shrimp continued their existence, moving
about their tiny bits of drab reef flat, surrounded by white
sand and turquoise water, blissfully unaware of human interest.
Three years passed by.
now works for a ship called the Rapture,
which was contracted to take a group of scientists through
the Northwestern Hawaiian Islands (NOWRAMP
2002 Expedition). The Expedition stopped at Midway and
Keoki brought the shrimp topic to the attention of the invertebrate
Dwayne Minton. Intrigued, Dwayne sorted through his
gear and dropped a shrimp trap on the tiny bit of reef.
Things looked good for the science, the shrimps were about
to be formally "discovered" (it is doubtful that
the shrimp cared, not a large mental capacity in a small
shrimp; but they do what they do very well).
when Keoki went to retrieve the trap the next evening, winds
came up and it became impossible to find the trap. The Rapture
was due to leave. It could be years again before another
try would be made. Score another point for the shrimp.
chance intervened yet again, as a crew member of an entirely
different ship, the deep sea exploration ship the KOK
fell ill. They steamed for Midway and the only doctor within
hundreds of miles. A doctor that the Rapture brought
along (diving expeditions can be dangerous). Dr.
Robert Overlock, a veteran of dive medicine and expeditions,
waited patiently for the KOK. If things went well, the Rapture
would still be able to leave on schedule late that night.
But one of the engines failed on the KOK; they fell behind
schedule and the Rapture had to stay on Midway another
day. It was time to go snorkeling.
had snorkeled this tiny patch of reef several times. Now
Collins and I went out to find the trap. There it was
with a tiny, beautiful shrimp inside. Only one had ventured
out and into the trap - fair enough. Science no longer needs
to collect numerous specimens to verify a holotype (true
type), two will do, one in a pinch. No need to disturb the
population, always take less than the predatory fish do.
And undoubtedly there are many of these little shrimp spread
out among the various small scoured and eroded reef flats
on Midway and possibly other Northwestern Hawaiian Islands.
are still just learning to look. We will take just our one,
the one that had the poor luck to venture into the trap
(no Darwinian jokes here or talk of the population giving
one to the volcano). Junji Okuno will get his pictures and
specimen, and Keoki will find out if he has a new species
- a species that, through a very chancy and circuitous path
has involved at least nine people so far. Perhaps it should
be named Rhynchocinetes multipersonatus.
Dr. Dwayne Minton, Keoki Stender and Hoover, John P., 1998.
Hawai`i's Sea Creatures, A Guide to Hawai`i's Marine Invertebrates,
Mutual Publishing, Honolulu, HI, Randall, John E., 1998,
Shore Fishes of Hawai`i, University of Hawai`i Press, Honolulu,
(1) In order to converse, talk, or (that
favorite of scientists) have a spirited debate and discussion
about an organism, biologists from countries all over the
world have to agree on a name. To do this, they use scientific
nomenclature, a system standardized throughout the world.
A species is a group of animals that can easily reproduce
with each other, resulting in fertile offspring that can
create more of their own kind.
the scientific name of the Blackspot seargent is Abudefduf
soridus. The genus is Abudefduf, the species is sordidus.
There are other similar fish, such as the Hawaiian sergeant
Abudefduf abdominalis and the Indo-Pacific sergeant
Abudefduf vaigiensis. They are all closely related
and may even form the occasional hybrid, but normally they
will not interbreed.
Look around you. Do you see any seastars roaming across
the floor? Most likely not, ditto for squids, worms, or
sea jellies (if you do, one wonders about where you live).
Yet the arthropods are there, for this group includes the
insects, spiders, centipedes and mites as well as crabs,
hermit crabs, lobsters, shrimps, mantis shrimps, skeleton
shrimps, and myriad more arthropod types. The external skeleton
offers protection from desiccation (drying) and attenuation
of fluids (from intrusion of fresh or salt waters into the
body fluids if the animal is immersed in water) as well
as protection from a myriad of other environmental and biological
threats. Arthropods are found in the deepest ocean trenches,
crawling slowly across ice flows in glacial regions, and
floating thousands of feet up in the atmosphere.
Marine photography is a very expensive hobby and profession.
Think about the cost of a good camera, triple that for an
underwater housing. Double that again for the underwater
lights. Add in a thousand or two for the SCUBA gear, then
flood the camera and start over (salt water is a very hostile
environment for sensitive gear). After the gear is put together,
add in every available extra hour for diving and don't quit
your day job - making a living solely at marine photography
is a tough business. There are probably less that 50 full
time professional marine photographers in the entire world.
Hoover, John P., 1998. Hawai`i's Sea Creatures, A Guide
to Hawai`i's Marine Invertebrates, Mutual Publishing, Honolulu,