title: Microcrystals coating the wing membranes of a living insect (Psocoptera: Psyllipsocidae) from a Brazilian cave.
abstract: Two specimens of Psyllipsocus yucatan with black wings were found with normal individuals of this species on guano piles produced by the common vampire bat Desmodus rotundus. These specimens have both pairs of wings dorsally and ventrally covered by a black crystalline layer. They did not exhibit any signs of reduced vitality in the field and their morphology is completely normal. This ultrathin (1.5 µm) crystalline layer, naturally deposited on a biological membrane, is documented by photographs, SEM micrographs, energy dispersive spectroscopy (EDS) and X-ray diffractometry (XRD). The crystalline deposit contains iron, carbon and oxygen, but the mineral species could not be identified. Guano probably played a role in its formation; the presence of iron may be a consequence of the excretion of iron by the common vampire bat. This enigmatic phenomenon lacks obvious biological significance but may inspire bionic applications. Nothing similar has ever been observed in terrestrial arthropods.
authors.affiliation: Natural History Museum of the City of Geneva, CP 6434, CH-1211 Geneva 6, Switzerland. charleslienhard@bluewin.ch
authors.forename: Charles
authors.initials: C
authors.lastname: Lienhard
authors.forename: Rodrigo L
authors.initials: RL
authors.lastname: Ferreira
authors.forename: Edwin
authors.initials: E
authors.lastname: Gnos
authors.forename: John
authors.initials: J
authors.lastname: Hollier
authors.forename: Urs
authors.initials: U
authors.lastname: Eggenberger
authors.forename: André
authors.initials: A
authors.lastname: Piuz
mesh_terms: D000818:Animals; D001938:Brazil; D002244:Carbon / Q000737:chemistry; D059552:Caves; D003460:Crystallization; D005260:Female; D007313:Insecta / Q000737:chemistry*; D007501:Iron / Q000737:chemistry; D008297:Male; D008855:Microscopy, Electron, Scanning; D010100:Oxygen / Q000737:chemistry; D013052:Spectrometry, X-Ray Emission; D013499:Surface Properties; D014921:Wings, Animal / Q000737:chemistry* / Q000648:ultrastructure; D014961:X-Ray Diffraction
chemical_list: D002244:Carbon; D007501:Iron; D010100:Oxygen