Variations: Rhax, Rhagion, Rhogalida (“grape-spider”)
The name Rhox indicates similarity to a grape. It may be the same as the spider known as rhogalida or “grape-spider” on Crete, although nobody is quite sure what a rhogalida is either. Aelian places it in Libya, but it is otherwise described as a common Mediterranean spider.
In any case the rhox, as described by Nicander, Philumenus, and Pliny, is a sort of spider or phalangion. has a toothed mouth in the middle of its stomach and short, stubby legs that move in succession – a description more reminiscent of a millipede or centipede than a spider. It is smoky or pitchy black in color. Its venom is instantaneously deadly, and known symptoms include web-like strands in the urine.
The short legs may be a misinterpretation, as the description and lethality both suggest the malmignatte or Mediterranean black widow.
References
Beavis, I. C. (1988) Insects and other Invertebrates in Classical Antiquity. Alden Press, Osney Mead, Oxford.
Kitchell, K. F. (2014) Animals in the Ancient World from A to Z. Routledge, Milton Park, Abingdon, Oxon.
A Book of Creatures 
“Strands in the urine” sounds terrifying.
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Web-like strands. In urine? Oh, oh god!
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Pee of spider’s web from spider bite? Sounds like some sort of bad parody of spiderman
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If the venom is instantaneously deadly, how do the victims have time to provide a urine sample?
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Might be an involuntary reaction. Plus I feel like it’s meant to mean that it instantaneously begins to kill you as opposed to instantaneously killing you
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So I guess the scenario here is that you find someone dead in a pool of their own urine, and check for strands to deterime the cause
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Or you’re tending to the person and you notice strains in their urine
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Oh what the heck? Just kill it with fire.
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is this Rhox(Creature) is already rare or extinct and i hope this Rhox Creature is still not extinct i hope so…
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It never existed 🙂
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