Friday, February 24, 2012

Friday Bug: Malevolent Red-eye



Ceresa basalis balefully considering Nature
Last May an exciting paper appeared in the highly regarded journal Nature that suggested that the bizarre 'helmets' that adorn tree-hoppers (Membracidae) may have been co-opted from the prothoracic wings of ancient insects - structures found only on fossils hundreds of million years old. Gene expression and morphology were combined in support of the hypothesis and, given that membracids often look like monsters from space, this paper caused quite a stir.
Ceresa basalis in a different colour
Alas, last month two nearly simultaneously published papers thoroughly debunked the re-evolution of ancient wings hypothesis (see below). Oh well, that's science: don't get too attached even to the most exciting hypotheses. Still, the treehoppers had their 15 minutes of fame (or rather 6 months).


Unfortunately, here in Alberta we don't seem to get any of the really spectacular treehoppers, but if you google you can see lots of striking pictures (great collection here). Instead, we have a rather understated and malevolent-looking Ceresa basalis Walker, 1851. This tree-hopping bug is a minor pest in orchards because it uses its saw-like ovipositor to lay eggs in the twigs of fruit trees killing shoots that might have borne fruit. 


The genus Ceresa was coined by Amyot and Serville in 1843, possibly in honour of Ceres the Roman Goddess of Agriculture (and presumably where we get our word 'cereal'). Some taxonomists disagree and use the genus Stictocephala Stål, 1869, which seems to mean 'punctured head'. Perhaps someone will one day coin a new genus Stictohypothesis.


References:
Kazunori, Yoshizawa. 2012. The treehopper's helmet is not homologous with wings (Hemiptera: Membracidae). Systematic Entomology 37(1): 2-6   DOI: 10.1111/j.1365-3113.2011.00606.x


Miko, Istvan; Friedrich, Frank; Yoder, Matthew J; Hines, Heather M; Deitz, Lewis L; Bertone, Matthew A; Seltmann, Katja C; Wallace, Matthew S; Deans, & Andrew R. 2012. On dorsal prothoracic appendages in treehoppers (Hemiptera: Membracidae) and the nature of morphological evidence. PloS One 7(1): e30137


Prud’homme B, Minervino C, Hocine M, Cande JD, Aouane A, et al. 2011. Body plan innovation in treehoppers through the evolution of an extra wing-likeappendage. Nature 473: 83–86. doi:10.1038/nature09977

3 comments:

  1. I saw the Yoshizawa paper and was thinking to write something about it, but now I don't need to :).
    I didn't know about the other paper, but it makes sense the NC crew should chime in - thanks for the link.
    It was a fun hypothesis while it lasted, but the single instance of prothoracic wings in the past 245 million years by something as simple as gene regulation did seem a bit strained.

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  2. A funny thing that appears when you click the link for the PLoS One article: "You are accessing a resource that is restricted to current students, faculty and staff of the University of Alberta. You need to enter your Campus Computing ID and password to gain access."
    I was not aware one needed to be a U of A student to read PLoS one!

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    1. Thanks Mike - the link is fixed now.

      PS - anyone can walk into the library and use the computer to do a literature search, not just students

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