Cyphochilus

Probably the same etymology as the former Cyphochilus orchid: from the Greek kyphos meaning "bent" and cheilos meaning "lip", because of the reflexed lip.{{cite journal |last=Honolulu Orchid Society and Pacific Orchid Society |title=Na Okika O Hawaii |journal=Na Okika O Hawaii = Hawaii Orchid Journal |url=https://books.google.com/books?id=0yYtAAAAIAAJ |publisher=Honolulu Orchid Society and Pacific Orchid Society |page=22 |issn=0099-8745|year= 1975}}

The whiteness of the scales is caused by a thin disordered photonic structure (≈7 μm) which scatters light of all wavelengths with the same efficiency, thus resulting in a white colouration. This is particularly interesting as the beetle's exoskeleton underneath the scales is black, meaning that the scattering events must be very efficient in order to achieve such high opacity.{{cite journal |author=P. Vukusic, B. Hallam & J. Noyes |title=Brilliant whiteness in ultrathin beetle scales |journal=Science |year=2007 |volume=315 |issue=5810 |pages=348 |doi=10.1126/science.1134666 |pmid=17234940|bibcode=2007Sci...315..348V |s2cid=9813819 }}

The white scales are composed of sclerotin, a modified form of the polymer chitin, and are whiter than paper or any artificial material produced as of 2022. That is they have a scattering mean free path shorter than any natural material thanks to the anisotropy in the spatial architecture of the fibres, which ensures a high packing efficiency whilst preventing optical crowding.{{cite journal|last1=Burresi|first1=Matteo|last2=Cortese|first2=Lorenzo|last3=Pattelli|first3=Lorenzo|last4=Kolle|first4=Mathias|last5=Vukusic|first5=Peter|last6=Wiersma|first6=Diederik S.|last7=Steiner|first7=Ullrich|last8=Vignolini|first8=Silvia|title=Bright-White Beetle Scales Optimise Multiple Scattering of Light|journal=Scientific Reports|date=15 August 2014|volume=4|issue=1|pages=6075|doi=10.1038/srep06075|pmid=25123449|pmc=4133710|bibcode=2014NatSR...4E6075B}}

The beetles are believed to have developed white coloration to camouflage themselves among white fungi. The chitin filaments are just a few micrometres thick – far thinner than a very fine sheet of paper. The elements are tightly packed,{{cite journal|last1=Cortese|first1=Lorenzo|last2=Pattelli|first2=Lorenzo|last3=Utel|first3=Francesco|last4=Vignolini|first4=Silvia|last5=Burresi|first5=Matteo|last6=Wiersma|first6=Diederik S.|title=Anisotropic Light Transport in White Beetle Scales|journal=Advanced Optical Materials|date=October 2015|volume=3|issue=10|pages=1337–1341|doi=10.1002/adom.201500173|doi-access=free|hdl=11696/65192|hdl-access=free}} scattering light efficiently, but still able to keep a degree of disorder in their shape.{{Cite news | url=https://www.bbc.co.uk/news/science-environment-28811232 | title=Beetles' whiteness understood| work=BBC News| date=2014-08-16| last1=Espuig| first1=Maria Dasi}} It has been shown how this strategy is evolutionarily optimised to produce bright whiteness despite the low refractive index of sclerotin.{{cite journal|last1=Wilts|first1=Bodo D.|last2=Sheng|first2=Xiaoyuan|last3=Holler|first3=Mirko|last4=Diaz|first4=Ana|last5=Guizar-Sicairos|first5=Manuel|last6=Raabe|first6=Jörg|last7=Hoppe|first7=Robert|last8=Liu|first8=Shu-Hao|last9=Langford|first9=Richard|last10=Onelli|first10=Olimpia D.|last11=Chen|first11=Duyu|last12=Torquato|first12=Salvatore|last13=Steiner|first13=Ullrich|last14=Schroer|first14=Christian G.|last15=Vignolini|first15=Silvia|last16=Sepe|first16=Alessandro|title=Evolutionary-Optimized Photonic Network Structure in White Beetle Wing Scales|journal=Advanced Materials|volume=30|issue=19|date=22 June 2017|pages=1702057|doi=10.1002/adma.201702057|pmid=28640543|doi-access=free|url=https://www.dora.lib4ri.ch/psi/islandora/object/psi%3A4000/datastream/PDF/Wilts-2018-Evolutionary-optimized_photonic_network_structure_in-%28published_version%29.pdf}}

Scientists have exploited the topology of the random network to fabricate materials of comparable performance for application as ultra-white paints and coatings. For instance, in 2018 Syurik et al. have developed a bioinspired PMMA-based material that scatters light efficiently and is flexible and switchable in appearance.{{cite journal |last1=Syurik |first1=Julia |last2=Jacucci |first2=Gianni |last3=Onelli |first3= Olimpia D. |last4=Holscher |first4=Hendrik |last5=Vignolini |first5=Silvia |date=22 February 2018 |title=Bio-inspired Highly Scattering Networks via Polymer Phase Separation

|journal=Advanced Functional Materials |volume= 28|issue= 24|pages= 1706901|doi=10.1002/adfm.201706901 |doi-access=free }}

Another recent example consists of the use of cellulose nanofibrils to fabricate ultra-white paper for cosmetics and coatings.{{cite journal |last1=Toivonen |first1=Matti S.|last2=Onelli |first2=Olimpia D. |last3=Jacucci |first3= Gianni |last4=Lovikka|first4=Ville |last5=Rojas |first5=Orlando J. |last6=Ikkala |first6=Olli|last7=Vignolini |first7=Silvia |date=13 March 2018 |title=Anomalous-Diffusion-Assisted Brightness in White Cellulose Nanofibril Membranes

|journal=Advanced Materials |volume= 30|issue= 16|pages= 1704050|doi=10.1002/adma.201704050 |pmid=29532967|url=https://www.repository.cam.ac.uk/handle/1810/282817|doi-access=free }} Or ceramic for tiles.{{cite press release|title=New cooling ceramic can enhance energy efficiency for the construction sector and help combat global warming—CityU research|url=https://www.cityu.edu.hk/research/stories/2023/11/10/new-cooling-ceramic-can-enhance-energy-efficiency-construction-sector-and-help-combat-global-warming-cityu-research|date=10 November 2023|publisher=CityU Hong-Kong University|first1=Edwin Tso Chi-yan|last1=Lin Kaixin|last2=Chen Siru}}

In 2023 a durable alumina-based ceramic based on Cyphochilus achieved a solar reflectivity of 99.6%, a record high, along with infrared thermal emission of 96.5%. It tolerates ultraviolet light and increases water evaporation and withstands temperatures of over 1,000 °C.{{Cite web |last=Irving |first=Michael |date=2023-11-13 |title=Ultra-white ceramic cools buildings with record-high 99.6% reflectivity |url=https://newatlas.com/materials/ultra-white-ceramic-cools-buildings-record-high-reflectivity/ |access-date=2023-11-13 |website=New Atlas |language=en-US}}

Finally, the researchers also say that the material can be easily mass produced, using common materials like alumina and a two-step process of phase inversion and sintering. And if white is too boring for some houses, the material can apparently be produced in other colors and patterns by adding extra layers.

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Category:Scarabaeidae genera

Category:Melolonthinae

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