"Among the numerous islands about Singapore, there is doubtless a wonderfully rich and unexplored region for the marine zoologist, who would find endless occupation for the dredge, as well as by ransacking the coral patches which occur in some places, and are very shallow at low-water. Although my opportunities were very limited while at Singapore, the magnificent species of Comatula (or feather-star) which came under my notice, as well as several new Crustacea of the genera Alpheus and Galathea, proved how well a systematic search would repay the observer with novel and interesting species."
"The best and most promising shore lies west of the town, and is covered with loose stones, upon which grows abundantly a species of Keramidia, an Alga allied to Jania; while upon these stones I met with seven species of Planaria, of very various and beautiful forms, and all probably new, as well as one species I had already found at Labuan. Nudibranchiates were rare, and several explorations only yielded a single species, a very beautiful rose-coloured one, probably Doridopsis rubra, which occurs among the Indian nudibranchs of Sir Walter Elliot, as well as among these described from Ceylon. Several species of Ascidian Tunicates, small hirsute Crustacea, and Peronias, but no Echinoderms (star-fishes or sea-urchins) of any kind. Among the zoophytes I deteced a specimen of the beautiful dendriform Actinia, already described from Pulo Enoe, so that Singapore must be added as a locality for the interesting sea-anemone."
"The harbour of Singapore was sometimes beautifully luminous at night... and on such occasions abounded with Noctilucae, which appeared to be the cause of the phenomenon. Sharks from time to time venture among the shipping, probably enticed by the garbage thrown overboard from the vessels, which also attracts a number of large hawks, known under the common name of Bromlykites, which are constantly hovering about, and darting down, seizing some floating mass in their claws."
In the day, anurans are more often heard than seen, calling as they do, when showers loom or evening beckons, from the forest floor, under a cloak of leaves and logs. My first encounter with Ingerophrynus (Bufo) quadriporcatuswas thus the result of a desire to unearth the source of a not unpleasant call below a boardwalk across a stream, on a day of long walks and heavy clouds. Described as a biphasic 'kree-kroo, kree kroo', the sequence emanated from a sandy bank with a thin layer of litter. After reaching down and flipping a few brown blades, the culprit revealed itself in a small, orange-brown toad with low ridges on its head.
A latecomer to the island's checklist of herpetofauna, the four-ridged toad escaped a century of biological sampling until 1989, when a specimen was found late in the evening on the floor of a forest on the mend. Since then, the species has been recorded from various localities on the mainland and off, though never in the haunts of a more urban toad. My second sighting took place late in the afternoon on a low ridge between a clear stream and an unprotected wood, where a large individual hopped briefly in view before vanishing into a pile of blades. The canopy by the trail prolongs the lifespan of pools that form after sustained rains, and the toads probably venture here to spawn in waters with few aquatic hunters save the nymphs of deep blue dragons. Subsisting on decaying vegetation, the tadpoles that survive masked assaults graze against time to sprout limbs and lungs before their chance at life on earth seeps away or surrenders to the needs of an environmental vision with little room for nature and no need for the wild.
There is a fine, and often broken, line between snails and slugs, for both terms, though useful in the field, reveal little of the relationships in a class of molluscs with convoluted life histories and do not form tidy bushes of their own on the voluminous tree of life. Many families of gastropods contain creatures with lustrous whorls as well as members with naked bodies that defoliate gardens at night. In the same clans of convergence are beastlets that have not gone the whole hog, retaining a shoebox of a shell to protect the vital organs but lacking the headspace for a true domestic retreat. In the sea, the label runs skin deep in headshield slugs, sidegill slugs, sap-sucking slugs and sea hares, for in these unstable orders, animals with external, if paper-thin, shells, veiled spires and internal plates share common descent with snails who have nothing to hide. Onchidids, and nudibranchs in sensu stricto, are among the few groups of slugs to preserve their immodesty without exception, with some of the latter going as far as to don see-through tunics.
One family of microsnails, Pyramidellidae, occupy an uneasy position between clades with mainly shelled species and those overrun by slugs. Like the group formerly known as Opistobranchia, pyramidellids place their gills behind their hearts. In all external regards, they are barely distinguishable from the inch-long black and brown things that crawl over mudflats and creep about sheltered bays and reefs in numbers that defy predators and offer small hermit crabs an inexhaustible supply of coils. But unlike potamids, batillarids and cerithids, pyramidellids lack radular teeth and betray affinities with sarcoglossids and false limpets. Instead of a radula, they wield a muscular invert that can be thrust out to become a long proboscis armed with a stylet. Though vaguely nemertean in design, the snails are not predators but ectoparasites of clams, scallops, mussels and tube-dwelling polychaetes, using their trunk to probe and pierce the body of their victim before sucking out vital fluids. The remains of hydroids and sponges have also been recorded in their guts.
Thus, it might not have been a coincidence that Otopleura auriscati, a large pyram with a spiral of chestnut markings and an Indo-West Pacific distribution, has been found on the low bund of Tanah Merah, where sabellid worms have colonised the rocks that face an artificial beach. The specific moniker refers to the ears of domestic felids, which the tentacles of the snail were perhaps fancied to resemble. Others have compared the appendages to the lobes of rabbits and donkeys, noting the curved outer surface and the ability of the snails to direct the concavity, which is coated with cilia and sensory cells, towards sources of food. Just visible near the base of the 'ears' are pigmented spots that probably do little more than tell day from dark. The snails are hermaphrodites and possess an invaginable penis, which simply means that the organ can be turned inside out to become a long, turgid whip used by the putative male to penetrate the vagina of his partner. There is no telling, though what signals they send to each other to determine who will grow a pair and who will notch a hit on the scoreboard of sexual abdomination.
Textbook narratives, which tell naught and show little of the adventures and autapomorphies that inflict every taxa, preferring instead to reduce the wealth of life on earth into single, generic species programmed to act with manufactured uniformity, also consign to plodding steps their lifelong struggle for survival, which in reality is a game of thrones where the victors are not necessarily the strongest and swiftest, and in which chance, in the shuffling of genes and vagaries of the environnment, and choice, in the decisions of sparring rivals and watchful mates, conspire to explore the limits of phenotypic expression and chart the associated gains in traits and losses in parts.
In observing odonates at some length, it becomes clear that sweeping descriptions fail to capture the diversity of methods used by the insects to secure their progeny. The females certainly lay their eggs in water. But some forget themselves, sinking to dangerous levels to insert their spawn, either alone or with their mates in firm attendance. Some barely get their feet wet, enjoying the stiff grip of males who play sentinel and take off in tandem when trouble looms. Others stay high and dry, cutting slits in reeds or depositing their clutch in treetop puddles or muddy banks. Damp moss, bromeliads, sewage lagoons, bamboo shoots, overhanging foliage and the grassy fringe of seasonal marshes also serve as oviposition sites that escape the depredations of oviphagous fish and opportunistic snails.
Within local woods, phytothelmata, abandoned receptacles and ephemeral pools in swampy terraces provide refugia for the odonates of broken canopies. Male dark-tipped forest skimmers, large dragonflies with bright blue coats and brown-yellow eyes, guard territories abutting waterlogged tracks, dashing to and fro with imperilled regularity to survey their perimeters before returning to a favoured perch. Where their flightpaths cross, Cratillia metallica may clash with grenadiers, which though markedly smaller, are similarly defensive of their breeding grounds. Below this livery of red and blue, clinging to the tips of curving leaves, are the sylvans, delicately built damselflies with electric blue thoracic markings that are barely apparent in the shadows above the seeps. Their wings are always held slightly ajar, but Coeliccia flees with reluctance, flinching a little when subject to unwelcome flashes of light and rising with languid effort to vanish on a nearby twig when pursued in earnest.
Short-lived waterbodies with a carpet of fallen leaves, though inaccessible to most piscine insectivores, are nonetheless visited by frogs, swamp eels, backswimmers and diving beetles. The dragons that thrive in this company have hatched and conserved strategies to shield their young from danger before the nymphs emerge to join the feeding frenzy. Podolestes orientalis, a large, long-legged damselfly that holds its hyaline wings wide apart, can be fairly abundant in these isolated wetlands, but the flatwings' presence seldom overwhelms – the adults rarely stray from the shade and their black and grey-blue stripes appear to deflect rather than draw attention to their slim profiles in a jungle of chiaroscuro hues. Their sex life is, to human eyes, a cloak-and-dagger affair, with few signs of courtship and a gamut of invisible cues that culminate in a brief wheel of hearts. Thereafter, the female, with her mate at hand, selects a stalk above or near the water and embeds her eggs into gashes carved by her ovipositor.
Sharing the flatwings' domain are small dragonflies that raise hell with furious displays of strength. Males of Tyriobapta torrida, when not attached to a vertical trunk, vie for dominance over stagnant pools, chasing each other around the swamp with audible fury and flaunting their colours in pockets of solar energy that illuminate their hindwing patches. After mating, the female dips her abdomen into the water to flick droplets of eggs towards the bank, repeating this cycle of strokes until her supply, or stamina, is exhausted. This approach probably helps the treehuggers, which, like other libellulids, have lost the tools to insert their eggs into botanical refuges, minimise losses to aquatic foragers that stick to deeper zones.
Some dragonflies choose spawning sites with little room for manouervre: swimming pools, water tanks, flooded roofs and feeding troughs where the fast-growing nymphs feast on other insect larvae or, in the absence of other prey, each other until a few attain adulthood. Pantala flavescens has cornered this ecological niche to conquer the globe, though its penchant for indiscrimination often causes the gliders to regard every shiny surface as a suitable substrate. One female, with her mate still in tandem, assaulted the scorching metal of a parking lot in the heart of Manado, where minibuses discharged hapless tourists into a cul-de-sac of dusty wares. Other libellulids also make questionable selections; female scarlet skimmers by the Maliau Basin in Sabah have been observed scorning a weedy creek, preferring to deposit in shallow ruts made by off-road vehicles. The eggs could well hatch in the damp mud, but it seems unlikely, though not impossible, that the neonates would have the means to escape dessication with a three-metre march to the closest brook.
Aeshnids are the only dragonflies in the region to retain endophytic habits. Like damselflies, female hawkers possess abdomens with a cutting edge, which allows them to pierce the fibres of streamside vegetation. Slender herbs and thin brush, however, lack the capacity to support the largest of the lot, a brute with the wingspan of a small bird and the presence of a ghost. Tetracanthagyna plagiata ranges across Sundaland but is rarely seen, as these giants hang high above lowland swamps and feed only at dusk and dawn. But the females, which bear the bulk of their species' burden, put in extra hours to atone for beastly dalliances, scanning their habitats for fallen logs and dead wood at the height of day.
The genus was erected in 1898, but the species was first described in 1877 from a Bornean specimen. And it was here, nearly a year ago, by a trail near the Maliau Basin Studies Centre, that a bruiser with pitchy brown wings and a body as thick as a finger laid her eggs early one afternoon, having settled on the high end of a stump about three metres above a winding trickle with steep banks. The hawker proceeded to probe the bark with a monstrous ovipositor, her abdomen flexing like a segmented worm as she injected a batch of protoformed hunters into the ligneous flakes. Odonate legs are not built for walking, so the ungainly steps of the labour were apparent in her slow inching up the trunk to gouge the chips and complete the mission of a mother who wields a stick that stabs before it spills.
A walker remarked to his companion as they passed me on the trail, "There's hardly any insects here". Earlier, a troop of young men had howled and hooted their way through an imagined wilderness, with a mere one or two having just enough grip on his senses to spot a fowl crouching in the undergrowth. Others raced down the track at speeds that send a shiver up my timbers whenever I place my belly on the ground to see what life looks like from a lower point of view. There were also a few parents who squandered the school break on local adventures, leading a gaggle of playmates who had not yet gained the ability to overlook a flutter of wings.
One of the most commonly encountered damselflies along forest tracks in the region, apart from Sulawesi where the genus is curiously absent, is Vestalis, a group of calopterygids with metallic green flanks and clear wings, although there are brilliant blue exceptions in Java and the Philippines. Adults of both sexes haunt sunlit clearings created by treefalls or chase the slim beams of broken canopies as the rays trace a daily route through the woods. They are also fond of perching by well-worn paths, which may offer the space to hawk for prey that'd otherwise lurk below their line of sight.
Vestalis amethystina is not rare in local reserves, but it's possible that many fail to detect the insects' emerald sheen on a wallpaper of waxy leaves. What gives the game away is usually a gleam of iridescence as the flashwing rises to a higher plane. They seldom run far; after a few minutes the damselfly usually floats back down to resume its watch on a low perch.
Except during courtship displays, calopterygids, unlike nearly all other odonates which employ alternate or phased strokes in normal flight, flap all four wings in synchrony, shooting through the air with ballistic speed and generating enough momentum to pierce the songbird barrier. The downside of parallel strokes, however, is a shortfall of power that restricts these jungle jewels to continuous stands of trees or the banks of shaded streams. Two other Vestalis species are now known in Singapore, with one enjoying a tenacious hold on existence by a vulnerable track and the other confined to a guarded swamp. But with protection a mere contingency in thrall to more productive imperatives, there is no telling how much longer these demoiselles and their dark, dappled home will survive a national longing for cleaner parks and the bright green lights of unnatural destinations.
"There is a small rocky islet or group of rocks near the SE. Point of P. Ubin called S'kodo, from a fancied resemblance of one of the blocks to a frog. Those in the middle are large and connected by sand in which some shrubs grow, and those scattered around are smaller and much worn by the waves. Some large rocks also lie in the sea on the south side of the central collection, and the longer sides of those run S.W. by W., N.E. by E. Parallel reddish lines or bands about half an inch broad traverse the surfaces and mark the planes of weaker cohesion. The sides of some of the blocks are peeling off in parallel layers. In some, another set of divisional planes, transverse to the former, are well marked. Where the rock is breaking down, these two systems of planes divide it into rhomboidal fragments."
– James Richardson Logan (1846), 'The rocks of Pulo Ubin, with some remarks on the formation and structure of hypogene rocks and on the metamorphic theory.' Verhandelingen van het Genootschap van Kunsten en Wetenschappen, vol. xxii. Batavia.
"The above is a rock which, at low tide, bears a remarkable likeness to a frog squatting. It is situated, with some other and larger rocks, in the old Straits of Singapore, between Changi and the eastern end of Pulau Ubin, near the latter. The local account of its origin is that, when mosquitos were as big as fowls, frogs were large in proportion, and that the living original of the rock in question in those days ventured a swim across the Straits, but before he could reach land daylight appeared, and the adventurer was turned to stone where he was."
– D. F. A. Hervey (1883), Batu Kodok (The Frog Rock), in Miscellaneous Notes, Journal of the Straits Branch of the Royal Asiatic Society 11.
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