R. Bicknell, G. Edgecombe, Christopher H. R. Goatley, Glen Charlton, John R. Paterson
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引用次数: 0
Abstract
Pedipalps – chelate ‘pincers’ as the second pair of prosomal appendages – are a striking feature of scorpions and are employed in varied biological functions. Despite the distinctive morphology and ecological importance of these appendages, their anatomy remains underexplored. To rectify this, we examined the pedipalps of the Australian black rock scorpion, Urodacus manicatus, using a multifaceted approach consisting of microcomputed tomography, scanning electron microscopy, energy dispersive X-ray spectroscopy, and live pinch force measurements. In doing so, we document the following aspects of the pedipalps: (1) the musculature in three dimensions; (2) the cuticular microstructure, focusing on the chelae (tibial and tarsal podomeres); (3) the elemental construction of the chelae teeth; and (4) the chelae pinch force. We recognise 25 muscle groups in U. manicatus pedipalps, substantially more than previously documented in scorpions. The cuticular microstructure – endo-, meso-, and exocuticle – of U. manicatus pedipalps is shown to be similar to other scorpions and that mesocuticle reinforces the chelae for predation and burrowing. Elemental mapping of the chelae teeth highlights enrichment in calcium, chlorine, nickel, phosphorus, potassium, sodium, vanadium, and zinc, with a marked lack of carbon. These elements reinforce the teeth, increasing robustness to better enable prey capture and incapacitation. Finally, the pinch force data demonstrate that U. manicatus can exert high pinch forces (4.1 N), further highlighting the application of chelae in subduing prey, as opposed to holding prey for envenomation. We demonstrate that U. manicatus has an array of adaptions for functioning as a sit-and-wait predator that primarily uses highly reinforced chelae to process prey.
期刊介绍:
Australian Journal of Zoology is an international journal publishing contributions on evolutionary, molecular and comparative zoology. The journal focuses on Australasian fauna but also includes high-quality research from any region that has broader practical or theoretical relevance or that demonstrates a conceptual advance to any aspect of zoology. Subject areas include, but are not limited to: anatomy, physiology, molecular biology, genetics, reproductive biology, developmental biology, parasitology, morphology, behaviour, ecology, zoogeography, systematics and evolution.
Australian Journal of Zoology is a valuable resource for professional zoologists, research scientists, resource managers, environmental consultants, students and amateurs interested in any aspect of the scientific study of animals.
Australian Journal of Zoology is published with the endorsement of the Commonwealth Scientific and Industrial Research Organisation (CSIRO) and the Australian Academy of Science.