Cyrene Reef offers an encounter that leaves many starstrucked, for the tidal flat is probably the last local stronghold of an asteroid once so abundant coastal communities thought nothing of gathering and grinding them up to fuel village gardens. The oreasterids dominate the fringes of the reef, where the seagrass starts to fray and the meadow has to fight the advance of long fingers of sand, and occur in densities that discourage ducks who can't count.
The population here is large enough to demonstrate the phenotypic variability of these massive sea stars. From standard issue brick and black to shades of red, pink and beige, the animals display a suspicious individuality that puts to shame the nerves of men who gladly think as groups and act like apes. Some stars sport outlandish hues of blue or green, a few boast an arm more (or less) than what the average bear, and a brazen number surround their knobs with areolas of dark pigment. The wide tonal spectrum appears to offer no discernible value for survival to a creature with no discernible eyes, but may tip the scales between a fatal appeal to collectors and the stewardship of curioius minds.
The future of this reef may well hinge upon the ability of these sea stars to fly the flag of conservation in a sea of liberal economics. If these icons foil the axe, their home will serve as a refugia for many other creatures that share a skin of spines and hydraulic tubes for feet. One new knob on the block is a fiendish cousin of Protoreaster with numerous nipple-like nodules, short marginal spines and a dorsal armament of granular plates. Larger specimens usually stand out in a scene of brighter stars, but since the first records of Pentaceraster in local waters, animals of less certain provenance have turned up on Cyrene and nearby flats, suggesting the possibility of hybrids or intermediates in a genus characterised by "a continuous chain of forms" rather than 'good' species that fit tidy taxonomical moulds.
Rather less striking, though occuring in vastly greater numbers, than the armoured giants are fossorial sand stars that have made the sandier bars of Cyrene a zone of pseudocopulation. Imprints of five-armed bodies and tapered discs riddle the loose dunes, which also house scattered colonies of stalk-eyed crabs that probably endure long fasts between fleeting chances to feed in damp squibs. In tender twos, and teasing threes, the stars maintain their grip on mates in a pose that is less a tryst in truth than a prolonged date with destiny.
Seagrass beds also teem with another class of echinoderms that bear little resemblance to their shapelier kin. The frail forms of synaptid sea cucumbers can often be seen tethered to green blades like lazy snakes with medusan heads of feathery tendrils that claw the currents for suspended particles. Other holothurians spend the day in unconsolidated sediments, performing the ecological functions of earthworms in pastures where free-ranging annelids occupy more aggressive niches. By displacing the silt and processing complex organic matter into botanically bioavailable compounds, the sandfish nourish the foundations of a habitat that feeds many but which remains largely out of foresight and absent from the minds who enjoy their fruits.
An even less visible component of the reef's visible infauna, heart urchins plough through the grains like spiny mice in slow motion. Some species are pallid creatures, but the few we came across last Sunday bristled with rosy tests and plumes of candy colours. Adept at life in rich deposits, the cordate diggers were noticably anxious to head back to safer depths; one observer of the spatangoids in a more arid region noted that "exposure was fatal to Lovenia elongata as it came up out of the sand and never got more than a foot in its dash for water."
More at home in the infralittoral zone are white sea urchins, which are pleasantly abundant on Cyrene though curiously not elsewhere in the southern shores. Despite their apparent inability to mix and match, the urchins' sartorial choices serve them well enough, rendering the balls of pretty spines nigh invisible on a carpet of broken shells and coarse fragments. Predators that rely on scent, however, will probably still home in on the animals and break through their vanity with acid wit and acerbic tongues.
A final mystery before the sun took its toil, this minute creature raised unsavoury questions about its identity. Resembling the rude end of some abandoned appendage, the organism declined to correct its dislodgement from the substrate, divulging few clues that could help us make head or tail of its vermicular form. Help from more authoritative sources pointed to a widespread genus of holothurians as common as they are cryptic. First described from Hawaii in 1907 and reported to live "a few inches beneath the surface of the soft, sandy bottom of numerous tide pools", these animals range from "burnt carmine and pomegranate purple" in colour and fill their guts with coral sand, which they probably ingest to extract a modicum of sustenance and maintain an ounce of mystery with regards to their precise diet and place in a shoal of questionable destiny.
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