Structure and Chemical Organization in Damselfly Calopteryx haemorrhoidalis Wings: A Spatially Resolved FTIR and XRF Analysis with Synchrotron Radiation

Susan Stuhr (1) , Vi Khan Truong (2) , Jitraporn Vongsvivut (3) , Tobias Senkbeil (1) , Yang Yang (4) , Mohammad Al Kobaisi (2) , Vladimir A. Baulin (5) , Marco Werner (5) , Sergey Rubanov (6) , Mark J. Tobin (3) , Peter Cloetens (4) , Axel Rosenhahn (1) , Robert N. Lamb (7) , Pere Luque , Richard Marchant (8) , Elena P. Ivanova (2)

1 RUB - Ruhr University Bochum = Ruhr-Universität Bochum
2 Swinburne University of Technology (Hawthorn campus)
3 Australian Synchrotron [Clayton]
4 ESRF - European Synchrotron Radiation Facility
5 Departament d'Enginyeria Quimica
6 School of Chemistry - Bio21 Molecular Science & Biotechnology Institute [Melbourne]
7 School of Chemistry [Melbourne]
8 Museum Victoria [Melbourne]

Insects represent the majority of known animal species and exploit a variety of fascinating nanotechnological concepts. We investigated the wings of the damselfly Calopteryx haemorrhoidalis, whose males have dark pigmented wings and females have slightly pigmented wings. We used scanning electron microscopy (SEM) and nanoscale synchrotron X-ray fluorescence (XRF) microscopy analysis for characterizing the nanostructure and the elemental distribution of the wings, respectively. The spatially resolved distribution of the organic constituents was examined by synchrotron Fourier transform infrared (s-FTIR) microspectroscopy and subsequently analyzed using hierarchical cluster analysis. The chemical distribution across the wing was rather uniform with no evidence of melanin in female wings, but with a high content of melanin in male wings. Our data revealed a fiber-like structure of the hairs and confirmed the presence of voids close to its base connecting the hairs to the damselfly wings. Within these voids, all detected elements were found to be locally depleted. Structure and elemental contents varied between wing membranes, hairs and veins. The elemental distribution across the membrane was rather uniform, with higher Ca, Cu and Zn levels in the male damselfly wing membranes.

Mots clés: X-RAY; FLUORESCENCE; MICROSCOPY; ODONATA; MICROSPECTROSCOPY; PIGMENTATION; TOPOGRAPHY; GENERATION; EVOLUTION; ZYGOPTERA

Domaines: Chimie

Susan Stuhr, Vi Khan Truong, Jitraporn Vongsvivut, Tobias Senkbeil, Yang Yang, et al.. Structure and Chemical Organization in Damselfly Calopteryx haemorrhoidalis Wings: A Spatially Resolved FTIR and XRF Analysis with Synchrotron Radiation. Scientific Reports, 2018, 8, pp.8413-1-8413-9. ⟨10.1038/s41598-018-26563-6⟩. ⟨hal-02976760⟩