Saturday 9 February 2013

PhD week 49: Slide mounting

Weevils slide mounted in Euparal

If you look back over previous blogposts (such as this one and this one), you'll see that I've agonised over different microscope mounting media like I were a character from Twilight. Swayed by my colleague, Rich Leschen, I have thrown my lot in with Euparal, and have spent the past week dissecting and slide-mounting weevil specimens. I will be unable to see the results for another two weeks or so, but initial indications suggest that it will have been a worthwhile exercise. The features that I particularly hope to see are characters of the mouthparts, where I hope to see differences between species that suggest different food preferences. Determining these differences will require careful observation, and it is hoped that these slide mounts will make the task much easier.

While it seems that I am currently at peace with my decision of slide mountant, there remain some dark clouds on the horizon. I recently read a paper that states that Euparal is becoming difficult to source due to a combination of concerns over its toxicity, and its continued availability. This paper suggests dimethyl hydantoin formaldehyde (DMHF) or polyvinylpyrrolidone homopolymer (PVP) as possible substitutes. Maybe my slide mountant angst will continue for a little while yet.

References:
Leschen RAB. 2005. Erotylidae phylogeny and review (Insecta: Coleoptera: Cucujoidea). Fauna of New Zealand 47: 1–108
Liberti G. 2005. Improved solutions of two water-soluble media for mounting beetle genitalia. The Coleopterist 14(1): 29–35.


Read:
   McCulloch D. 2010. A History of Christianity: The First Three Thousand Years London: Penguin

Websites:
DNA barcoding blog—Seven Deadly sins of DNA barcoding
Tom Robinson—Māori Macron Characters

Listened:
Angel D'Agostino—Adios Arrabel

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