Gram Blue and Forget-me-not

These two Lycaenids cause much confusion in amateur butterfly watchers. Here's one note on how to distinguish them.
Gram Blue on a Shrub

Gram Blue, Euchrysops cnejus – is a common Lycaenid of India. Distributed throughout the southern and western regions, it is not found in the higher altitudes.
Gram Blue male - upper side
Male Gram Blues are smaller compared to the female counterparts. The males have a shade of blue and black on the upper wings compared to the females, which have more of a brown shade with blue near the body.


Gram Blue Female - upper side

Although found in all the seasons, they are abundant during post-monsoon. They prefer flying on low ground, feeding on various flowers of weeds as well as important plants. The larval food plant is Vigna trilobata, generally called as Wild Bean, which is in abundance during monsoon and flowers post-monsoon. The larvae, like most of the Lycaenid larvae, are attended by ants.

Gram Blue on Vigna trilobata flower
The adults might live in a group of around 10 – 20 in a square meter area which is a high number where males fight for a partner. A several males will try to mate with a female; however only one succeeds in mating.


Gram Blue - Female towards the left and two males on the right trying to mate
A mating pair of Gram Blues
Gram Blues are often seen with several other blues, such as Pea Blue, Common Cerulean and Zebra Blues. Another blue – Catachrysops strabo (commonly called Forget-me-not) is confused with Gram Blue, however both are rather distinctive in morphology as well as behavior.
Forget-me-not, as it is commonly called is a comparatively larger butterfly than Gram Blue.
Forget-me-not (Left) and Gram Blue (Right)
The upper wings of male are silvery blue which are distinctively different than Gram Blue whereas the females have a predominant thick blackish brown border with white elsewhere and light blue near the thorax. Forget-me-not Male upper side
The hind wings are quite different from Gram Blue, with less dominant two black spots on the hind-wing and a small spot at the margin of (closer to the apex and far from the head) fore-wing.
Forget-me-not under side

It is distributed throughout India.

Forget-me-not Male - this one was engaged in a territorial dispute
The flight of Forget-me-not is random and fast and is a territorial butterfly (males) often seen fighting rival males. They settle abruptly and are commonly seen basking in the late morning sun.

3 comments:

  1. My search for the identity of a butterfly from the Blues family led me to your blog, Aniriddha.
    It is a pleasant surprise; the blog is tastefully done and your presentation on the Gram Blues is very informative with precise text and excellent pictures.
    -Ram Thakur

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  2. I was searching for the differences between gram blue and plains cupid and stumbled upon this. It is very informative. Can you please give the difference of these two alongside. I think plains cupid and gram blue are even more confusing and hard to distinguish.

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  3. Very well described. Thank you.

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