Subject: Black Butterfly, blue spots, white stripe Costa Rica
Location: Atenas, Costa Rica
July 24, 2014 8:28 pm
What kind of butterfly is in the attached image taken in Atenas, Costa Rica
Signature: Many thanks!
We quickly identified your Brush Footed Butterfly in the family Nymphalidae as a Starry Cracker, Hamadryas laodamia saurites, thanks to the Butterflies of America website, and though there is not much information, we did glean that individuals with white stripes of this sexually dimorphic species are females. According to the Butterflies of Amazonia site, the common name is the Starry Night Cracker. The site goes on the explain the common name thus: “The butterflies are commonly known as Crackers due to the ability of the males of several species to produce a sound similar to the crackling of bacon in a frying pan. The sound is produced as the butterflies take off, and is made by twanging a pair of spiny rods at the tip of the abdomen against bristles on the anal claspers. Only males can produce the sound, but both sexes can detect it – their wings have tiny hollow cells covered in membranes that vibrate in response to sound, and stimulate nerve endings. The purpose of the sound is not known. It may possibly deter competing males from occupying the same territory, or could act as a trigger to initiate the first response from a female during courtship.” The chatty Butterflies of Amazonia site also states: “Photographing Hamadryas can be a frustrating experience, as both sexes spend most of their time basking high up on tree trunks, often 10 metres or more above the ground. They sit there for hours with wings outspread, always facing downwards to keep a watchful eye for potential mates. At times they descend and bask much lower down, at a height of just a couple of metres, but at the slightest disturbance they immediately fly back to the tree top. They remain there until the intruder has left the vicinity, and then descend the tree trunk in a series of short hopping flights, dropping a short distance each time until after half an hour or so they have resumed their original position.” Other than being dead, the specimen you photographed appears to be in perfect condition, showing no wear on the wings, which causes us to speculate that it fell victim to a blood-sucking predator, like possibly a robber fly.
Thank you so much!!! Really appreciate how quickly, and how thoroughly you answered my question.