48 rue Major Pétillon, 1040 Brussels, Belgium.
Surfaces and Thin Films, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, NL-9747 AG Groningen, the Netherlands.
J Insect Physiol. 2020 Nov-Dec;127:104114. doi: 10.1016/j.jinsphys.2020.104114. Epub 2020 Sep 6.
The pierid butterfly Colias croceus (Geoffroy in Fourcroy, 1785), established in the Azores archipelago, is polymorphic with six forms, C. croceus f. croceus ♂ and ♀, C. c. f. cremonae ♂ and ♀, C. c. f. helice ♀, and C. c. f. cremonaehelice ♀. We investigated the optical mechanisms underlying the wing colouration of the butterflies by performing spectrophotometry and imaging scatterometry of the variously coloured wing areas and scales. The scale colouration is primarily due to wavelength-selective absorption of incident light by pterins expressed in granular beads in the wing scales, but thin film reflections of the scales' lower lamina and scale stacking also contribute. Three forms (croceus ♂ and ♀ and helice ♀) are consistent with the patterns of the well-known 'alba' polymorphism. We postulate the coexistence of a second polymorphism, 'cremonae', to understand the three other forms (cremonae ♂ and ♀, and cremonaehelice ♀), which are characterized by the absence of red pigment, presumably due to the differential blocking of erythropterin expression.
Pierid 蝴蝶 Colias croceus（Geoffroy in Fourcroy，1785）在亚速尔群岛建立，具有六种形式的多态性，C. croceus f. croceus♂和♀，C. c. f. cremonae♂和♀，C. c. f. helice♀，和 C. c. f. cremonaehelice♀。我们通过对不同颜色的翅膀区域和鳞片进行分光光度法和成像散射测量，研究了蝴蝶翅膀颜色形成的光学机制。鳞片的颜色主要是由于在翅膀鳞片中的颗粒状珠子中表达的蝶呤对入射光的波长选择性吸收，但鳞片的下表皮的薄膜反射和鳞片堆积也有贡献。三种形式（croceus♂和♀和 helice♀）与著名的“alba”多态性模式一致。我们假设第二种多态性“cremonae”的共存，以理解其他三种形式（cremonae♂和♀和 cremonaehelice♀），它们的特征是缺乏红色色素，可能是由于对血红素表达的差异阻断。
