Enterobius vermicularis.
The benefits of a ring flash in photographing an orifice can be seen in this interesting case where the main subject area is clearly visible. When photographing minors, the legal implications of the subject material needs to be considered to avoid contravening the Protection of Children Act.
Hood
C
C
D001003:Anal Canal / Q000469:parasitology; D000818:Animals; D002675:Child, Preschool; D004757:Enterobius / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D010058:Oviposition / Q000502:physiology*; D010123:Oxyuriasis / Q000469:parasitology*; D010270:Parasite Egg Count; D010781:Photography