Download Corallimorphs

Classification
• Order corallimorpharia: Corallimorphs very
coral-like, but they do not secrete a
skeleton
– phylum Cnidaria
• Class Anthozoa
• Radially arranged tentacles or pseudo tentacles, if
present. The most popular varieties contain
symbiotic zooxanthellae,
Types
• Corallimorpharians are found in all oceans
• tropical to polar & shallow to deep waters
• Most common types six genera:
Actinodiscus, Rhodactis, Discosoma,
Amplexidiscus, Psuedocorynactis and
Ricordea
• Psuedocorynactis are rare, orange ball
corallimorph are the most photographed
Characteristics
• Resistant to disease, & extremely
competitively dominant
• Nothing seems to settle near
corallimorpharians,
• Never seen anything able to take over
space occupied by corallimorpharians
Characteristics
• Co-existence with other species is
possible, but the corallimorpharians never
seem to "lose a battle
• Only animals able to resist nearby
settlement & competition by Aiptasia
anemones. For this trait alone, they must
be admired!
Characteristics
• Coelenterates are animals classified in the
phylum of aquatic invertebrates, which is
responsible for more envenomations than
any other marine phylum
• Almost 9000 species of coelenterates
exist; approximately 100 are toxic to
humans
Characteristics
• Coelenterates have a gastrovascular cavity
with a single opening, which functions for
both digestion and circulation
• Another feature is the presence of stinging
cells called nematocysts
Characteristics
• The phylum is divided into 4 major
classes, as follows:
– Hydrozoa (Portuguese man-of-war, fire
corals)
– Scyphozoa (true jellyfish)
– Cubozoa (box jellyfish)
– Anthozoa (sea anemones)
Disease
• Severe rash and itching or pain
• Unset in 1st 12hrs, may be able to
penetrate lycra wet suit
• Nematocysts are poison mechanism
Portuguese man-of-war
• The Portuguese man-of-war is a free-
swimming organism with tentacles
hanging from the float (ie, main body)
• Two species of Portuguese man-of-war
exist
• The larger species, Physalia physalis, lives
in the Atlantic Ocean from Nova Scotia to
the Caribbean Sea
Types
• The smaller species, Physalia utriculus, lives in
•
•
•
the Pacific and Indian Oceans.
The tentacles may be 100 feet long and may
contain as many as 1 million nematocysts
Even detached tentacles are a hazard on the
beach because they are capable of releasing
venom for several weeks
Two confirmed deaths caused by P physalis
have been reported
Types
• The fire corals Millepora typically are
encountered off the Florida Coast and in
the Caribbean
• The hydroid corals are sessile creatures
that attach to rocks, coral, seaweed, or
pilings
• Mild stinging sensation occasional burning
pain and lymphadenopathy
Types
• In US the true jellyfish are the most common
•
•
species causing envenomation
The sea nettles Chrysaora & Cyanea are located
along the Atlantic coast, with a high
concentration near the Chesapeake Bay
Envenomations caused by scyphozoans are less
severe than those caused by the Portuguese
man-of-war
Types
• Box jellyfish Chironex fleckeri
• Sea wasp Chiropsalmus quadrigatus are
the most toxic marine organisms
• Found in northern Australian waters but
not in North American waters
Types
• Sea anemones and the corals are sessile
creatures, and the anemones found within
the US tidal zones have minimal toxicity
• Corals are important components of living
reefs, and the risk of infection from a coral
cut is of greater concern than its toxic
effects
Pathophysiology
• Most toxins contain a complex mixture of
polypeptides and proteins, including
catecholamines, histamine, hyaluronidase,
fibolysins, kinins, phospholipases, and
various hemolytic, cardiotoxic, and
dermatonecrotic toxins
Pathophysiology
• The toxin of coelenterates is located in the
nematocysts. Only toxic organisms have
nematocysts capable of penetrating the
human skin and releasing the toxins.
Pathophysiology
• Nematocysts are present on the outer surface of
•
•
the tentacles or near the mouth
Nematocysts are contained within the cnidoblast
or the outer capsule
Cnidocil (ie, trigger point) is on the external
surface of the cnidoblast and can be triggered
by mechanical or chemical stimuli. A hollow,
coiled, sharply pointed, threaded tube containing
venom is at the base of the cnidocil.
Mortality/Morbidity:
• Fatal envenomations caused by the box
jellyfish occur in tropical waters of
northern Australia
• At least 63 deaths have been documented
Disease
• The most common presentation is a
painful papular-urticarial eruption. Lesions
can last for minutes to hours, and the rash
may progress to urticaria, hemorrhage, or
ulceration.
• Ocular contact has resulted in
conjunctivitis, chemosis, corneal
ulcerations, and lid edema.
Disease
• Chronic reactions include keloid formation,
hyperpigmentation, fatty atrophy,
contraction, and vascular spasm.
Uncommon local reactions include
angioedema, recurrent reaction, contact
dermatitis, and papular urticaria
Disease: Sea bathers' eruption
• Sea bathers' eruption is an intensely pruritic
•
maculopapular eruption developing on skin that
has been covered by swimwear. It probably is
caused by the larvae of thimble jellyfish (Linuche
unguiculata). A rash develops approximately 24
hours after exposure and may last 3-5 days.
Systemic reactions include headache, malaise,
fever, nausea, vomiting, muscle spasm, pallor,
respiratory distress, hemolysis, and acute renal
failure.
Irukandji syndrome
• Ingestion of jellyfish has resulted in abdominal
•
pain, cramping, and generalized urticaria.
Irukandji syndrome (consisting of backache,
arthralgias, myalgias, vomiting, sweating,
pyrexia, tachycardia, dyspnea, and
hypertension) may occur after envenomation by
the small jellyfish (Carukia barnesi). Although
the systemic reaction can be significant, the
sting is frequently not visible.
Irukandji (Carukia barnesi)
Carukia barnesi has a single retractile
tentacle, from 50 to 500 mm long,
hanging from each of the four corners
of its bell.
image by L. Gershwin
Small jellyfish approx 2cm diameter bell, responsible for an unusual
and dramatic syndrome observed following stings in northern
Australia, especially north Queensland
Irukandji is the name of an aboriginal tribe that once lived in the
area around Cairns in north Queensland.
Unlike Chironex fleckeri (Box Jelly Fish), Irukandji are found
mostly in the deeper waters of the reef, although they may
be swept inshore by prevailing currents
Divers and snorkellers are particularly at risk
Irukandji (Carukia barnesi)
• Stings have occurred from Childers to
Broome, and a similar syndrome has been
described elsewhere in the Pacific.
• Greater than sixty people are hospitalized
with this potentially fatal syndrome
• Initial sting is usually not very painful
Irukandji (Carukia barnesi)
• 5-45 (avg 30) minutes after being stung,
severe backache or headache & shooting
pains in their muscles, chest & abdomen
• Nausea & vomiting, anxious, & restless,
HBP
• Rare cases pulmonary edema potentially
fatal if untreated
Irukandji (Carukia barnesi)
• 1964, Dr. Jack Barnes spent several hours
in a wetsuit lying in the water near Cairns
searching for a jellyfish responsible for
“irukandji syndrome”
• To Dr Barnes' delight, a thumbnail-sized
jellyfish swam past his mask
Irukandji (Carukia barnesi)
• He stung himself, his son and a surf life
saver to check that the jellyfish he had
caught was responsible for 'irukandji
syndrome‘
• All three ended up in hospital
• For Dr Barnes' dedication, the tiny jellyfish
was later called Carukia barnesi
Irukandji (Carukia barnesi)
• In January 2002, a tourist swimming near Hamilton
•
•
•
•
Island in the Whitsundays died after being stung by a
jellyfish
His death was reported by the press to have been
caused by an irukandji
58-year-old man had a pre-existing medical condition
that made a jellyfish sting fatal
He had a valve replacement and was taking warfarin to
thin his blood
After he was stung, his blood pressure increased which
caused a brain hemorrhage leading to his death.
Irukandji (Carukia barnesi)
• Treatment with narcotic iv and anti-
emetics
• Topical vinegar & shaving or scraping skin
• Supportive iv fluids and electrolytes
Chironex fleckeri
15 tentacles
On each or 4
corners
Up to 9 tentacles
On each of 4
corners
Does not cause
Irukandji synd
Chiropsalmus