A gander through the powdery stuff enshrouding the wings of ape fly spalgis epius

Background: Spalgis epius, the ‘Ape Fly’ is a small butterfly that belongs to the lycaenids or blues family. The powdery stuff sheathing their wings are called scales which are the main factor for wing coloration. Ape fly on appearance shows blue color on the dorsal wing area and ventral wing area shows ash color. The wing scales forms vivid or indistinct patterns and helps the organism to protect itself by camouflage, mimicry and warning. Wing scales perform a great role in the natural history of Lepidoptera. Objective: To examine the various types of wing scales, their morphology and dimensions (Length and Width) in Spalgis epius. Methods: The Standard method of Grodnitsky and Kozlov (1991) is used. Several hundreds of scales were scrapped off from the dorsal and ventral wing separately into a glass slide. The sample is fixed using xylene and studied under light microscope. The dimensions are measured with micrometry. Results: A wide variety of scales has been observed from dorsal and ventral wing area. A total of 175 scales were studied which include 88 varieties from dorsal side and 87 varieties from ventral side. On analyzing the blue coloured dorsal wing area several colored scales including dull brown, cream, pale black colored scales are identified. Many broad, flat and short sized scales are observed in this area. Here the majority of scales are devoid of dendations. Flat, thin, glassy type scales are also observed. For most of the scales, the abwing and adwing are broad. The length and width of the scales vary. Transverse lines in scales are not clearly seen. The blue color of dorsal wing is not due to blue scales instead it is because of structural colors formed when the light passes through the other colored scales. The dimensions of dorsal wing scales ranges between 82.74µ-110.32µ in length and 55.16µ-74.86µ in width. The ventral wing scales shows several long scales unlike the dorsal side. Several grayish white colored scales are identified. Long narrow scales are the major scales. In the ash colored ventral wing some reddish brown scales can be seen in the strigae. The scales are darker towards the upper lamina and colorless towards the lower lamina. Thin transparent glassy type scales are observed. The wing scale dimensions ranges between 90.62µ-130.02µ in length and 47.28µ-78.8µ in thickness. Conclusion: Studies focusing on butterfly wing scales are important as the scientific works based on the above is only minimum. A wide variety of scales are been observed in Spalgis epius with varying dimensions. Structural and coloration aspect of wing scales lead to the development of new ideas in science and technology.