Friday, 16 March 2012

PhD week 2: Weevil larvae

Unidentified broad-nosed weevil larva
Unidentified broad-nosed weevil larva

This week, in addition to continuing to prepare my proposal (focusing primarily on comparative phylogenetic methods), I was able to spend a little bit of time looking at specimens of weevil larvae. Weevil larvae are legless grubs with few features that obviously distinguish different groups from each other. However, on closer (and patient!) inspection, there are a number of subtle features that enable the identification of many larvae to generic level. One of the questions I will be looking at is: can the larvae of different Irenimus species be differentiated from each other?

The key to any taxonomic work is familiarity—familiarity with both the organisms being studied, and with the methods used in the process. I haven't tried to identify larvae before, so this was my chance to get to grips with the process and characters involved. I was able to find a few larval specimens that I had lying around, and so I tried my hand at dissecting them and getting my eye in regarding larval morphology.

Conveniently enough, my introduction to weevil larvae went well. The process of dissection was straightforward, and I was able to navigate my way around the keys available fairly happily. Unfortunately, I was unable to properly identify the specimen shown above, but that's not too surprising given that only a small proportion of New Zealand's weevil larvae have been described. I also haven't yet got myself a microscope slide mounting procedure that I'm really happy with, so I haven't progressed on to that aspect of the work yet.

May BM. 1993. Larvae of Curculionoidea (Insecta: Coleoptera): a systematic overview. Fauna of New Zealand 28: 1–226

Paradis E. 2006. Analysis of Phylogenetics and Evolution using R. 1st Edition. Use R! New York: Springer

Solodovnikov AY. 2007. Larval chaetotaxy of Coleoptera (Insecta) as a tool for evolutionary research and systematics: less confusion, more clarity. Journal of Zoological Systematics and Evolutionary Research 45(2): 120-127

Freckleton RP. 2009. The seven deadly sins of comparative analysis. Journal of Evolutionary Biology 22: 1367–1375

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

Kirkpatrick R. 2007. Path of Revenge. Sydney: Voyager

Psalms 18–21; Hosea 4

Wikipedia—Thomas Burnet

Wikipedia—Charles Peirce

Coleoptera Poloniae—Database of Polish Beetles (includes photos)


Cricket: New Zealand vs South Africa 2nd test match

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