Tuesday, August 16, 2011

Thunder Bugs

Although seemingly rare to find inside tightly closed 18th and early
19th century frames, the sight of clusters of thunderflies inside more
recent miniatures, appearing as tiny black specks, is common.

It appears as though there is no 'modern' frame that they cannot penetrate,
and once there, they perish. 

Thunder bugs, also known as
thunderflies, storm flies and thrips, are a pest as they destroy
crops, and have recently succeeded in entering even the LCD moniter!
About 1mm long or less, they love to hide in crevices.

Here, one is stuck to the painted side of the ivory.

Another one has 'glued' with the gum arabic in the painting.

Interestingly, we have not seen Thunder bugs in 17th. century frames.
This could be due the the design of the frame , or a change 
of environment in the late 19th. and early 20th. century


  1. porsena said...
    What an interesting story! The plant-feeders seem unlikely to colonise pictures. About half the known thrip species feed on fungi and there's one group that feeds exclusively on fungal spores. Thrips, or thunderflies, can spread rapidly into new areas and they do like tight spaces.

    Without knowing when the dividing line between infested and thrip-free frames occurs, my immediate suspicion is drawn to the late 19th century introduction of paper products made from chemical wood pulp, which first appeared in the 1870s. The white rot fungus is capable of growing on cardboard or paper and actually thrives in chemical pulp mills, where it has found a contemporary use in effluent treatment. Paper before the 1870s (and some after, of course), was cotton-based and wouldn't support this fungus.

  2. Thank you very much Porsena for this knowledgeable explanation. We wondered if the paper content was the attraction and you have confirmed this