As non-social creatures, P. cochleariae thrive in lower population densities, where they benefit from reduced competition and abundant resources which improve their individual fitness.
[6] Their elytra are a reflective dark blue-green color and are abundantly dotted with dorsal glands in a parallel lined pattern.
[8] Research has revealed that certain olfactory and visual cues are paramount in the mustard beetle’s ability to locate host plants.
[9] From a visual perspective, it was found that beetles naturally orient towards vertically or horizontally striped patterns and that they can accurately discriminate between green and yellow leaves.
[9] Researchers have conducted new experimentation into the metabolism of mustard beetles, and more specifically, how they cope with defense mechanisms propagated by Brassicaceae plants.
[10] Brassicales have been shown to have a binary defense system in which glucosinolates and myrosinases form a toxic hydrolysis compound that predators find aversive.
[10] Interestingly, forming aspartic acid conjugates as a way of metabolizing glucosinolate is different from what other Brassicaceae herbivores have been shown to exercise.
[10] P. cochleariae, as well as other species of leaf beetle, produce iridoids throughout all stages of their life cycle to defend themselves from predators that may threaten their survival.
When faced with a predator, they secrete the defensive iridoids out of their dorsal glands (appearing in the form of droplets) to deter the threat and ensure a higher rate of survival.
Mustard leaf beetles are benefited by and thrive in lower population densities, this has been found to play a crucial role in their development and fitness.
Group individuals experienced higher rivalry and competition for limited resources which likely played a role in the time spent in larval phase.
Personality is conveyed within 5 to 14 days within adulthood and appears to remain relatively constant and stable throughout the adult lifetime of Phaedon Cochleariae.
Isolated beetles have fewer potential mates to copulate with, which reflects a lower activity level relative to group individuals.
[15] Although CHC composition in females and males of the mustard leaf beetle species are identical, the concentration of the compound differs between the sexes.
This likely means that the beetles rarely use CHC concentration to differentiate the sex of a potential mate, rather they use tactile bodily cues.
This is increasingly evident as habitats fragment due to global warming and climate change, and risks the development of inbreeding depression.
[17] Mustard leaf beetle personality can be influenced by inbreeding, with inbred individuals showing traits of higher boldness due to their reduced fitness.