Paguroids are among the most abundant and amusing decapods in the littoral zone, where they flourish on the bleached remains of gastropod mortality. Shorn of their periostraca, the shells lose what colours they had in life, fading into a dull coat of nacre which soon acquires a fresh body of settlers: algae and sea anemones land on the whorls, while slipper limpets and anomurans with soft bottoms squirrel themselves into coils that can still support life from without. On soft expanses, tiny diogenids trundle in the shells of Umbonium, moon snails, cerithiids, batillariids, whelks and frog snails. On rocky shores, windrows of columbeliids, drills, periwinkles, planaxids and trochids are fought over by crabs who gather in ungainly piles on slippery slopes to partake of scarce resources or indulge in common appetites.
Outnumbered than the minute hordes, though less likely to be mistaken, and thus overlooked, for sluggish molluscs by casual beachcombers is a hermit crab with orange-brown longitudinal stripes on its limbs and eyestalks. Clibanarius infraspinatus serves as the archetype of its superfamily on local shores, shuffling as it does on Changi's seagrass flats, Chek Jawa's sand bars and the sinking core of Cyrene Reef. Smaller animals probably compete with their punier cousins for modest lodgings, but adults have a knack for finding the shells of noble volutes, spiral melongenas, conches, bonnets and balers, which often seem several sizes too large for the crab. Mature crustaceans expend more energy on gonads than growth, though, so there is merit to hoarding ill-fitting drags, especially when they'd withstand a good few moults and are scattered to boot. The main drawback to domestic tightwadry is probably an accumulation of dead weight: porcelain crabs, amphipods, polychaetes and slipper limpets worm their way into the lumen to hitch a ride and share the spoils of messy feeders.
At least eight other congenerics occur in Singapore's waters, though few attain the bulk of the buff bruiser. One species of similar length but lighter build is Clibanarius longitarsus, which forages in the mangrove creeks of Pulau Semakau as well as silty habitats on St John's Island, Pasir Ris and Pulau Ubin. In life, this hermit is rather variable in colour, being "mottled brown and blue or light brown with several blue patches" and having brown claws covered with blue or blue-green tubercles and spines.
Another, rather uncommon, paguroid encountered on occasion at Beting Bronok and muddier parts of Changi Beach is Paguristes longirostris, which, despite its generic designation, is a member of the same 'left-handed' family as Clibanarius. The carapace of this hermit is, however, "nearly naked" and the outer portions of the wrist, hand and fingers are distinguished by flat, overlapping tubercles which lend the claws a "squamiform appearance". The subequal chelipeds also sport bright blue patches on the inner surface of the carpi, which may serve as signals for intraspecific recognition or signs of reproductive health. There is little to indicate if these crabs, which have been recorded from Singapore and the Bay of Bengal, enjoy a comparative advantage in areas of a certain depth or substratum, but the genus is known to produce few, relatively large eggs that hatch into larvae exhibiting abbreviated development. Such a strategy, unlike the scattershot approach of those who gamble on short bursts of fertility, hinges on the persistence of stable states and a climate of certainty, vestiges of a kinder, gentler time that no longer exists in this age of miracles in which life is chained to a perpetual horizon with neither space for exploration nor room for thought.
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