Coconuts injured by Eriophyes or Aceria guerreronis, the eriophyid coconut mite.
Hartford Hammond Keifer
<p><a rel="nofollow" class="external text" href="https://naldc.nal.usda.gov/download/CAT87208955/PDF">An Illustrated Guide to Plant Abnormalities Caused by Eriophyid Mites in North America</a> p.121. 
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Probably originally from ERIOPHYID STUDIES B-14. 20 pp. Calif. Dept. Agr. Bur. Ent., H.H. Keifer.