Sunday, April 13, 2014

A Dragon Mite for the Buckeyes

Although a student of the Ohio State University, I have comparatively little "Buckeye spirit". I came here due to the excellence of the entomology department—not out of any sense of protean loyalty to the institution (not having grown up in Ohio), or particular hostility towards that University Up North (which I also considered for my undergraduate career). 

I did feel a surge of pride and excitement, however, upon hearing of the discovery of a new genus and species of mite (Osperalycus tenerphagus) right here on Main Campus: considering that this is only the second member of its family to be found on the North American continent, the discovery by graduate student Samuel Bolton (who works across the hall from my admittedly unassuming job in the Triplehorn Insect Collection) is an occurrence worthy of attention.

LT-SEM photograph of protonymph (above) and tritonymph (below) of Osperalycus tenerphagus (USDA)
O. tenerphagus is mainly noteworthy in terms of its membership in the family Nematalycidae: a taxon consisting of five monotypic genera (including Osperalycus), all known from fine sand in Africa, Eurasia, the Americas, Australia, and New Caledonia. They are easily distinguished by the wide separation of leg pairs I-II and III-IV, genitalia much closer to the hindmost pair of legs than to the body's posterior, and (most prominently) a ridiculously elongated body (see above). Due to their resemblance to the Chinese lung, the Nematalycidae have been called "dragon mites" (Bolton, 2014). In an interesting side note, all nematalycids appear to be parthenogenic (Bolton et al., 2014). 

LT-SEM photograph of O. tenerphagus when contracted (right) and at rest (left) (also USDA)
This draconine prolongation is associated with accordion-style bodily locomotion (in a word: inching), much like that seen in organisms as unrelated (and vastly larger) as earthworms and caecilians. It is facilitated by the heavily contractile and flexible integument of these mites (see right), which is enervated by longitudinal muscles running the length of the nematalycid body (all 600 micrometers of Ohio's only species; Wheeler, 2014). As a whole, this is an adaptation for a life in the interstices of sand particles.

Which is why where O. tenerphagus (the "Buckeye dragon mite") was discovered makes it special: not in an arenaceous environment like the rest of its kin, but in a surprisingly clayey soil ("Worm-like mite species found"—ScienceDaily). The presence of rutella in the Buckeye dragon mite's mouthparts is also significant in clearing up questions of phylogeny: it confirms that nematalycids belong in the Endeostigmata (a probably paraphyletic taxon) as opposed to the Trombidiformes (Bolton et al., 2014). 

But to me, the location will always be the kicker: you see, I've obliviously walked over the ground where Samuel Bolton found the creature at least four times a week since September. One never knows what can be found beneath one's feet...

Go Bucks!

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Bolton, S. J. (2014, February 20). New Species of Bizarre, Worm-like Mite Discovered on Ohio State University Campus. Entomology Today. Retrieved 4/13/14 from http://entomologytoday.org/2014/02/20/new-species-of-bizarre-worm-like-mite-discovered-on-ohio-state-university-campus/

Bolton, S. J.; Klompen, H.; Bauchan, G. R. and Ochoa, R. (2014). A new genus and species of Nematalycidae (Acari: Endeostigmata). Journal of Natural History. Retrieved 4/13/14 from http://www.tandfonline.com/doi/pdf/10.1080/00222933.2013.859318      

Wheeler, Q. (March 1, 2014). New to nature No 119: Osperalycus tenerphagus. The Observer. Retrieved 4/13/14 from http://www.theguardian.com/science/2014/mar/02/new-to-nature-osperalycus-tenerphagus  

Worm-like mite species discovered: A species from this 'extremophile' family hasn't been described for 40 years. (February 28, 2014). Retrieved 4/13/14 fromhttp://www.sciencedaily.com/releases/2014/02/140228155800.htm