Rare biological phenomenon in dragonflies sighted at Kole wetlands
When Renjith R.V and Vivek Chandran spotted a peculiar dragonfly, the Scarlet Skimmer (Crocothemis servilia), in the Puzhakkal area of the Kole wetlands in Thrissur last year, little did they know that they were documenting a very rare biological phenomenon.
The male dragonflies typically have prominent blood red colouraton in almost all their body parts, including the head, thorax, abdomen and legs, and the female is a pale yellow in colour with a dark brown thorax and legs.
But the one they spotted on July 14 as part of the Kole Odonata Survey 2019, was “part red and part yellow”.
Later, while compiling data, they were thrilled to find that they had recorded gyanandromorphism — a very rare biological phenomenon.
Gynandromorphs are chimeric individuals having both male and female tissues, and are viewed by the scientific community as a genetic aberration.
Even though common in some arthropod taxa such as Crustacea and Arachnida, the paper says it is very rare in Odonates and only 30 individuals from seven families have been reported with the condition worldwide.
The spotted individual showed bilateral gynandromorphism of only the thorax, half of which showed blood red colouraton as in males, and the other half had the pale yellow characteristc of females.
The individual had a mix of male and female external characters, ranging from almost entirely female to about equally divided.
They are predaceous insects comprising the dragonflies and damselflies.
An arthropod is an invertebrate animal having an exoskeleton, a segmented body, and paired jointed appendages. Arthropods form the phylum Euarthropoda, which includes insects, arachnids, myriapods, and crustaceans.
A gynandromorph is an organism that contains both male and female characteristics.