Hookhead Rasp

285 million years PE, the flickbill skewers continue to evolve into new species, each one using its specialized beak to make use of different types of food, and being quick to colonize newly-forming habitats in the late hothouse.

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The hookhead rasp is a large descendant of the teetering taptracker that has evolved in woodlands that have come to cover Serinarcta's upland plain, a region now known as the nightforest for its polar location and prolonged winter darkness. Weighing up to 15 pounds as an adult, it is a poor flyer with short wings, but very strong wing and toe claws, plus its namesake hook-like upper mandible, all of which make it a skillful climber. Like its ancestor, much of its diet is still wood-boring insects that it chisels out of tree trunks with its bill, but its size has increased along with its prey. The trees grow tall here, and like in the longdark swamp, the seasonal changes encourage the emergence of huge insects in the warm, dark winter and spend the summer growing as grubs within the trees of the forest. Preferring to feed in darkness, though forced to forage by daylight in the summer, it roosts in dark tree holes and advertises its claim over territory with loud cackling calls. A narrow ridge of bright red plumage running from nostril to crown also serves as a visual signal by which other rasps can see it from a distance, at least during sunlit period, and so avoid it, as they will fight if they meet. 

After proclaiming its territorial claims, a rasp leaving its den clambers up and down the trees in pursuit of this rich food, always climbing with its head upright, and descending downward in this same position. Occasionally it may fly for several meters, but only if it must, and its flight is clumsy. For its size, the adult rasp is a very heavy bird, for most of it bones become solid with age, which makes them stronger and more resistant to falls as well as heavy exertion, such as ripping apart trees with their wing claws. When it detects a grub, mainly by scent, it begins digging and seeks to stab its prey with its beak. It tongue is more robust than in earlier species, the tooth-like serrations along its dorsal surface sharper and more blade-like, and able to fold backwards to lie almost flat. Long and tentacle-like, this tongue can extend over 10 inches through the narrow hole punctured into the tree with the beak to dismember the grub into smaller pieces that it drags out and into the mouth. The size of its insect prey means that the rasp is now also able to take on vertebrates, and will occasionally kill larger prey such as molodonts if it finds them hiding in their dens within the tree, but even more unusually, it will engage in parasitism of cyngnosaurs and other large megafauna in a manner that is most similar to a nightbiter or, on earth, a cookiecutter shark. Particularly during the winter, when they have the advantage of darkness to cover them, the hookhead rasp will approach resting land animals and savagely bite them, tearing a mouthful of flesh and effectively peeling it off, then scurrying away.

The hookhead rasp's larvae are insatiable carnivores, so much so that the rasp has adapted a novel way to feed them which greatly reduces its workload while trying to raise them. Its ancestors adopted a larder system, filling a nest with many small food items that the larvae would initially eat before leaving the nest and hunting insects on their own within the same holes under the tree bark that the grubs they hunted lived. Rasps typically only provide a single larger prey item as their larder, usually some sort of other bird or tribbethere almost as big as themselves, and considerably bigger than what the species normally preys upon. It is the male's sole parental responsibility to catch this animal, which is the major demonstration of fitness by which the female determines a male to be a suitable mate: if she finds a male's offering satisfactory, she will mate with him and then take it for her young, and he will go his own way again. She eviscerates the carcass and lays her eggs directly within it to develop, but only a single larvae ultimately survives, as the strongest cannibalize those which hatch later or grow at a slower rate. The female may or may not defend the nest against predators, depending on its location, but the chick requires no additional food, and by the time it pupates and emerges as a fledgling, its mother will have left. The juvenile is a stronger flyer than the adult and is strictly insectivorous, closely resembling its earlier ancestors and only gradually increasing in size and strength over the next three years before full maturity.