Gosh, one would have thought that with the lack of sleep and a not-so-accommodating tummy, the last thing that one would have in mind is food. Sweet, sweet tooth, I wonder what would I be like without thee? :) Anyway, continuing from where I left off, this time round we shall be graced by the presence of some of the more graceful anthozoans (which can literally be translated into ‘flower animals’).
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To distinguish the Haddon’s from the other carpet anemones is fairly simple. This particular anemone (Order Actiniaria) has a tentacle-free central area (1-2cm). Often, the bulbous tentacles are band-like and/or two-toned. Also, the Haddon’s lives in sand and can/does completely retract when disturbed [2]. Not sure how this big guy does it for a spectacular size such as its own. Besides, Haddon’s (unlike other carpets) lack any coloration, spots or markings on the underside and its column [1] (right).
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Being lone wolves, Haddon's Carpet Anemone (Stichodactyla haddoni) are usually found living singly in the shallow waters of the Indo-Pacific and the Red Sea [1]. And with their swathes of multi-coloured tentacles and their ability to grow into immense sizes (up to 92cm/3 feet), they share similarities with the lush and luxurious Persian carpets [2]. When in the pink of health, the anemone is sticky to the touch and rather reluctant to let go, when gently felt.. or if it’s a prey in its grasp. These guys are also one of the few anemones that can cause severe reaction in humans. Hence, it’s best to keep those fingers to yourself. =) [1]
AND, here’s an interesting fact for the day: ALL Carpet Anemone species are fish eaters [2]. Check this picture out. Who would have thought? Fish-guzzling carpet in action! 
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Peacock anemone (Order Ceriantharia), so called because it comes in an array of rainbow colours and patterns. Unlike true anemones, peacocks have two types of tentacles – the inner ring of tentacles are usually shorter than the outer ones. The longer ones gather food before handing it over to the shorties, which then bring it (food) into the mouth. And true to its namesake, both long and short tentacles can differ in coloration [3].
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And see the way the tentacles flop limply over the animal? That’s because the Peacock does not have a ‘door’ to seal off the entrance, hence, the top part of the tube (tentacles too) flops over and effectively shuts any opening to reduce water loss.
Besides being known as the Peacock Anemones, these cnidarians are also known as the Tube Anemones, with the reason being that these animals live solitarily and permanently in a tube that’s burrowed under terra. These tubes are formed using specialised stingers (aka ptychocysts) special to the Peacocks. These stingers create sticky strings that lace together with sand and slime before hardening to form a tube. Only a short portion shows up above ground while the rest (1m or more) spans underground [3].
Since the Peacock is unable to tuck its tentacles into its body column like a true sea anemone (Order Actiniaria), the tentacles are bundled up together before retracted into the tube by strong muscles running along the body column [3].
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(left): Colonial anemones (Order Zoanthidea) are another kind of anthozoans that aren’t true anemones. They are frequently mistaken for corals, but unlike corals, they are completely soft. Zoanthids are usually found in groups of many individual polyps, which are joined to one another. And just like the Peacocks, zoanthids have tentacles that come in twos. But this time, they are double rows of tentacles that are of the same kind and equal length (short too!). Zoanthids, like true anemones, do not live in tubes [4].
(right): Banded bead anemones (Order Actiniaria) are true blue anemones like the Carpets. The Banded Beads are common on shores, especially on rocks high on the intertidal zone, often in rock pools. When the tide recedes, the anemone tucks its tentacles and appears like a dark blob of jelly (unfortunately, naive as I was then, I forgot a macro-shot of the creatures… blast!). >_< Once the tide returns, it unfurls its tentacles and start feeding.
References:
1. http://www.liveaquaria.com/product/prod_display.cfm?c=497+499+602&pcatid=602
2. http://www.wetwebmedia.com/carpetanemones.htm (identification of various carpet anemones)
3. http://www.wildsingapore.com/wildfacts/cnidaria/others/ceriantharia/ceriantharia.htm
4. http://www.wildsingapore.com/wildfacts/cnidaria/cfringtentacles.htm
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