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Submitted on
April 12, 2011
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False Ammonite by NocturnalSea False Ammonite by NocturnalSea
Another group of hypothetical anomalocarids from the Devonian. The large creature in the center is the False Ammonite (Pseudammonites ptilobrachiones). Its great appendages have evolved into massive “brooms” that sweep plankton from the water as the animal glides along, propelled slowly by its spade-shaped flippers. Much like a hermit crab (and its own distant relative, the Blue Squid-crab) the creature’s soft body is protected inside a discarded ammonite shell. Unlike the squid-crab, however, the False Ammonite’s shell actually floats thanks to a symbiotic siphonophore (Megaera deformibaccata) that inhabits the inner chambers. The striped pink tentacles dangling from the aperture of the shell are Megaera’s own fishing tentacles, while the orange, pear-shaped bodies around the rim are its reproductive zooids. (Meagaera, by the way, is named after the titular monster from the Hammer Horror film, The Gorgon).
Algae readily colonizes the shell and body of the False Ammonite, evident here in the rough brownish-yellow coat and green “toupee”, as well as the green cyanobacterial fuzz on the fin. There're a lot of creatures living in this algae "forest". Go here to read more about them: [link]
To the right of the False Ammonite is another hermit anomalocarid, the Sun Drifter (Medusocola silvadorsum). Drifters inhabit the stomachs of jellyfish, where they gain protection and free transportation. Like P. ptilobrachiones, they too are filter-feeders that use their elongated great appendages to snare plankton. If necessary, Drifters can leave their jellyfish hosts and swim freely, as the one on the left is doing.
Most Sun Drifters harbor a small colony of Gardner Crabs (Demeter hortulanus), an arthropod distantly related to the Cambrian “Lace Crab” Marella. Gardner Crabs feed on cyanobacteria that they cultivate on the back of their Drifter. Like a human gardener, they constantly tend and prune their harvest, brushing it clean with their furry antennae and keeping it generally free of other herbivores (although some do get through, as evidenced by the chiton that is feasting in the lower right).
Those strange, vertically-oriented creatures are highly-modified placoderms called Thief Fish (Scutoculus longinares). They hang out under the False Ammonite, using their large, fan-like tail fins to keep themselves vertically-oriented, and steal larger bits of food from the anomalocarid’s brooms. S. longinares have transparent bubbles of hard skin covering their eyes to protect them from the fine, stinging hairs that cover the False Ammonite’s arms and from the siphonophore’s tentacles.
Floating at the surface are a couple of By-the-Wind Sailors (another kind of siphonophore) and a few pelagic barnacles similar to the modern-day Buoy Barnacle Dosima fascicularis.
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Ruschman Featured By Owner Aug 11, 2014
I'm not hating your artwork one bit; I think it's fantastic!!
Hermit Anomalocarids sound like a cool idea, when you think about it. :)
Ruschman Featured By Owner Aug 11, 2014
Now, were these animals for real, or did you invent them based on theories of what the ceticarids could have done?
NocturnalSea Featured By Owner Aug 11, 2014  Professional Traditional Artist
These guys are totally invented.  I actually got the inspiration for them form my pet hermit crab.  I was watching it crawl across my bed one day, and I thought its claws looked remarkable like Great Appendages.  This was right around when Schinderhannes bartelsi was discovered, so my mind was already filled with ideas for as-yet unknown anomalocarids that might have existed in the millions of years between the Cambrian and Devonian.
Ruschman Featured By Owner Aug 12, 2014
Maybe we would find fossils of ceticarids inside curled natiloid shells. I definitely love the idea for the "filter-feeding" prongs.
BTW I love Hermit Crabs as pets.
Dinofuzz Featured By Owner May 6, 2014  Hobbyist General Artist
Awesome ecosystem!
MrMadManiac Featured By Owner Jun 17, 2013  Hobbyist
I swear, on my first glimpse, I thought it was wearing a bright red bow-tie.
Chrestovenator Featured By Owner Mar 25, 2012
This is amazing, you've created an entire ecosystem and plunked it right in the middle of the Palaeozoic (Devonian? Silurian?). I like how you have speculative Cambrian-derived critters coexisting with more recent beings (like the chiton and the barnacles). And the false-ammonite itself is just so bizarre it's impossible not to love (even with the manowar-gonads on its face). This is truly excellent.
AmnioticOef Featured By Owner Apr 15, 2011
This is great.
NocturnalSea Featured By Owner Apr 16, 2011  Professional Traditional Artist
The-Episiarch Featured By Owner Apr 13, 2011
I quite like that Phronima-inspired "Sun Drifter" on the upper right.
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