Upside down jellyfish (Cassiopeia xamachana) are another member of the order Rhizostomae. The species name, xamachana, means Jamaican although their natural habitat is in no way exclusive to Jamaican waters. Populations exist throughout the Gulf of Mexico andCaribbean as well as along the coats of Florida. They are also present half way across the globe in the Pacific Ocean. Although not native to these waters, upside down jellyfish were introduced to the Hawaiian Islands during World War II most probably from jellyfish polyps attaching themselves to the underbellies of war ships coming back from the Philippines.
This species is prevalent in shallow, warm tropical waters such as mangrove swamps. They are often called mangrove jellyfish because they are frequently found in large aggregations in these swampy regions. Unlike many species of jellyfish, upside down jellies are completely marine. None have been found in brackish or fresh waters.
These jellies spend their lives completely differently than most jellyfish. Jellyfish typically spend much of their time drifting freely on the ocean's currents. Upside down jellyfish are free swimming until they reach about 2 cm. Then their bell inverts and they sink to the bottom of the ocean floor. From there they will spend the majority of their adult life upside down on the muddy substrate with their tentacles pointed up to capture the ever present zooplankton from water columns.
Much like blue jellies, upside down jellyfish have a symbiotic relationship with zooxanthellae. This is the same symbiosis that occurs with many jellyfish and coral species. In addition to providing essential nutrients, these golden algae also produce oxygen to help support respiratory metabolic functions the jellyfish needs to survive in oxygen poor environments. This is of particular importance to upside down jellyfish because they spend the vast majority of their life nestled in muddy substrate and must rely on their food to come to them. Because of their specialized eating habits, upside down jellyfish are usually found in nutrient rich waters with high concentrations of decaying matter to support the zooplankton teaming within these swampy, saltwater environments.
Upside down jellies have flat, saucer shaped bells. Their umbrellas are typically greenish grey or blue in color. They have a central depression or exumbrella in their bell. The exumbrella acts as a suction device to help them stay anchored to the ocean floor. Rather than a single mouth opening, they have 4 elaborately branched oral arms. These arms have a frilly, lace-like appearance similar to many green, leafy vegetables. They are often referred to as cabbage-head jellyfish because of these appendages. It isbelieved that this species a filter feeder and also relies on some form of absorption of dissolved nutrients directly from the water to supplement its nutritional needs.
Upside down jellyfish do not directly inject their prey like most jellyfish do. Their nematocysts (stinging cells) are controlled by the cnidocil. This is the equivalent to a mechanically or chemically triggered grenade launcher. The stinging cells launched from the cnidocil produce a cnidoblast that will stun or paralyze prey in the immediate vicinity. The jellyfish then begin ingesting their prey with their primary mouth openings. Once the prey is reduced to food fragments, these nutrient particles are passed on to secondary mouths for further digestion.
The jellyfish's cnidoblasts also function as a self-defense mechanism. If abruptly disturbed, large groups of these jellies will launch themselves upward from the ocean floor and release their nematocysts. This massive venom release into the water is usually sufficient to ward off potential predators. The toxic compound is generally inconsequential to human beings. It may result in an itchy or tingling sensation of the skin or a rash on individuals more sensitive to the venom.
Upside down jellyfish can reach up to 14 inches in diameter in the wild. In captivity a maximum growth potential of 8 inches is more realistic. Depending on their size in captivity, upside down jellyfish can be fed zooplankton, or small invertebrates and fish. In order to allow their symbiotic algae to properly photosynthesize, a lighting system conducive to a marine reef tank is highly recommended. These jellies have a higher temperature tolerance than most scyphozoan medusa. Medusae or adult jellyfish can be found year round. However the optimum temperature for these adult jellies is between 75-78 F. This simulates the height of the adult season. Upside down jellyfish typically strobilate during summer or early fall. Whereas most scyphozoans strobilate during the winter months.
Designer Prom Dress TipsA designer prom dress isn't cheap so you need to be confident that the gown will show you off at your best. However, just buying an expensive designer label isn't going to guarantee that you'll look beautiful for Prom; in fact the opposite can be true. Here are some tips to help make sure you get one that's best for you.
Whether buying a cheap department store gown or a beautiful designer prom dress a girl can find it difficult to find one that flatters her. She maybe a confident teenager who has no problems buying the latest trendy jeans and tops,Online Shoes Sale, but buying a formal gown leaves her at a loss. This isn't surprising as most girls will have never worn one before. However, by following certain guidelines, much of the stress and confusion can be eliminated, so buying the gown and accessories can actually be fun.
Like wedding gowns, prom dresses run at least one size smaller so pick dresses a size larger and you'll get a perfect fit. Also, if shopping online, many websites have a measurement guide for the designer gowns they sell. By following these carefully, you can be sure it'll fit perfectly.
Don't set your heart on one particular style of dress. Different styles of dresses complement different body shapes. So, keep an open mind. Try out different styles to find the one that best flatters your figure. Girls are often amazed that they look fabulous in a dress that they had previously dismissed. When you visit the boutique, don't be shy. Try the dress on; after all it's your money, your time and your big day. Besides,Replica Fashion Store, a dress looks more beautiful when worn than on a hanger.
Seek the opinions of friends and family. After all, they know you best and will offer you honest advice on what styles and colors best suit you. But remember, it's your day so the final decision is yours.
The sales person in the boutique will be very knowledgeable about the designer prom dresses they stock. They also understand just how difficult it can be for a girl to find that perfect dress. Talk to them and ask for their advice.
For many, there's nothing worse than going to Prom only to find someone else wearing exactly the same gown. Buying a designer dress helps, as they're more unique,In Fashion Store, but your best bet is to talk to your friends and let them know which dress you're buying; that way they'll look for something different. To have the largest selection you need to start shopping earlier in either January or February.
Buy the dress a couple of months before hand so you can make any alterations that are need. Just about all gowns will require some minor alteration; remember; Prom time is a very busy time for alteration services. Try to buy your accessories at the same time you buy your dress. Many boutiques and online retailers will have a selection of accessories that will complement the dress.
Finally, set a budget and stick to it. If you spend more than you had originally planned to on that beautiful designer prom dress then you should reduce the amount you spend on the accessories.
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