Varying shades of green, gold and brown cloak many grasshoppers, allowing them to browse and sing with relative impunity. But not a few acridoids get away with stark patterns, bold stripes and loud colours that scream for attention on a stage of growing blades. The probable result of having imbibed pigments and poisons that were shunted to the outer layers of their body, these bright hues offer diurnal hunters a strong hint that the hopper they eye will fail to sate their hunger. For the bug, it pays to avert disaster by advertising one's unpalatability before a predator lunges and leaves with a mouthful of mutual regret.
A good number of local acridids belong to a subfamily known as Catantopinae or spur-throated grasshoppers, which are distinguished by a prosternal process visible only from below. Some catantopines are drab things, but others, like this unidentified Lucretilis with green femora, salmon forewings and dark transverse lines, present striking counterpoints to the typical tones of orthopteran wallflowers. Another eye-catching member of the family is a small grasshopper with a coat of black velvet and an overlay of yellow bands. Found in urban retreats as well as the island's wilder parts, Traulia azureipennis has a specific name that refers not to some dirty appendage but to a blueish sheen on the hindwings, which lie hidden under stiff tegmina. The females are rather less flashy, but both sexes sport a dash of red on the lower region of the tibia, which is scarcely visible at rest and may serve as a signal to conspecifics rather than as a warning to ill-intentioned creatures. A few close relatives exude fluid, presumably noxious, from trachael glands or spew bile when handled. Whatever chemical defences the waspish males possess is, however, dismally recorded and the animals more often than not prefer to swing low than stand their ground when they feel threatened, as if the instinct to flee still trumps the power to put their taste to the test.
In the isolation of lands at the confluence of fiery plates, some catantopines have ditched both flight as well as flightiness, losing their wings or lacking the span to sustain themselves in the air. Unlike the case of birds in far-flung isles, this trend is thought to be less a response to the absence of predators than an adaptation to oligotrophic environments, in which individuals who divert their energies to early maturity and reproduction gain an edge over those who squander resources on muscles and veins. All representatives of the brightly coloured genus Chitaura in Sulawesi, for one, are effectively flightless.
As in Australia, where the subfamily has exploded and attained pestilential proportions, Sulawesi's acridoid fauna is dominated by (forest-dwelling) catantopines (53 species out of a known total of 62), with species from other subfamilies occupying mainly open habitats or jungle fringes. This may be a legacy of the group's early arrival, radiation, and subsequently, high rate of endemicism following periods of geological fragmentation and fusion. Grasshoppers were not the primary target of a recent trip, which focused on the miniature whirlybirds of a beleagured ecozone, but at least two unusual acridids were observed: one at Bogani-Nani Wartabone National Park with pied flanks and lemony tibia, and the other, found in good numbers by a creek some miles outside the park, an apterygous beauty with hindlegs that grade from orange to yellow to green to blue. Males and females are similarly attired, so the finery is likely to be aposematic or function as a tell-tale sign of individual fitness. Whatever their purpose, the gaudy arrays certainly make the hoppers hard to miss on the tangled bank of a swift, shallow river and amid the foliage of a brook where dragons fill the air and on which villagers ride to do their washing and watch their children play in the slow ebb of a day in the hills, between dales of palms and cornfields of rich, dark soil that feed a multitude of parishes with no lack of plans and no end to hope.
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