Monday, 10 February 2025

The Kleidocerys Conundrum - Resolved?

I've been bothered about Kleidocerys for a while - specifically, is Kleidocerys ericae a separate species from the familiar Birch Catkin Bug, Kleidocerys resedae? See: The Kleidocerys Conundrum. When I cogitated about this two years ago it was obvious that DNA was the way out of the mess. A recent paper spurred me into action - time to find an answer. 

In a nutshell, DNA barcoding is a method of identifying species by sequencing a short, conserved region of DNA. The ideal DNA barcode gene needs to have enough variation between species to tell them apart, but be conserved enough within a species so it can be easily identified. The 5' portion of mitochondrial cytochrome c oxidase subunit I (COI-5P) has become the standard Arthropod barcoding marker. A vast amount of DNA barcode data has now accumulated. At the time of writing, the International Barcode of Life (iBOL) initiative - www.boldsystems.org - has examined 26 million specimens, 21 million of them from Arthropods. Helpfully, the BOLD website makes it (relatively) easy to examine them, so I plunged into looking at the Kleidocerys data. 

CAVEAT: It's been a while since I did this professionally, and even then, it wasn't really my specialism. What follows is my interpretation. Others reading this may well know far more about it than I do, in which case, please let me know. 

A DNA dendrogram - tree diagram (if it was good enough for Darwin to sketch in his notebook, it's good enough for me) - is a visual representation of the genetic relationships between different organisms, or in this case, DNA sequences. Here's the tree for the Kleidocerys COI-5P barcodes:

Kleidocerys dendrogram
(click for larger image)

In summary:
  • Kleidocerys resedae and K. ericae each form sequence clusters with similar levels of relatedness. This supports the idea that they are indeed separate species.
  • Kleidocerys privignus, very similar in appearance to K. resedae but which is said to occur on Alder, also appears to to be a separate species. (NB: one privignus sequence clusters within the resedae sequences (blue arrow) - presumably a misidentified specimen). 
So what does it mean for me? That I probably need to keep looking for K. ericae, although it is possible that it may not occur in VC55. It also means that I should probably look for K. privignus - time to target the Alders this year. 

Has this made my life simpler? Nope. When did technology ever do that?
 









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