Orangeblack Hawaiian Damselfly

Megalagrion xanthomelas is commonly found near the coastal wetlands of the Hawaiian Islands. The species is also found in wetlands fed by basal springs and different levels of elevation throughout the Hawaiian Islands. Megalagrion xanthomelas is usually found between the range of 60 to 610 meters above sea level, with some populations recorded as high as 1000 meters above sea level. Megalagrion xanthomelas thrive in habitats that have tall Guinea grass lining the perimeter of the water source. Females will use the tall leaves of the Guinea grass to lay their eggs onto when mating while males perch on top of the leaves, waiting to chase out intruder males. The inlet of Pearl Harbor used to be a common habitat for the species Megalagrion xanthomelas. After World War II, Megalagrion xanthomelas declined in numbers over the years and is no longer present within the inlet of Pearl Harbor. The decrease in numbers is due to civilian and military airport traffic and housing constructed within the inlet to create a military base.

The life cycle of Megalagrion xanthomelas is done fully within water sources that have a salinity level lower than 8 ppt (Tango). The order Odonata, including Megalagrion xanthomelas, undergo incomplete metamorphosis within their life cycles. The life cycle of the Megalagrion xanthomelas contains four stages. The first stage of the life cycle is the egg stage which lasts about 21 days before the larva emerges. Next, is the pre-larva which takes anywhere between 11 and 17 days to complete. The third stage is the naiad. Naiads can develop from a range of 103 to 111 days. The last stage is the adult, which is the only stage that does not require water to be completed. When females lay their eggs, they lay their eggs fully submerged within aquatic plants. When the eggs are laid, they are covered by an outer shell called a chorion. The chorion provides a structure that allows for the intake of oxygen while preventing any level of salinity from entering and killing the baby organism inside. After the life cycle is completed, the adult stage of Megalagrion xanthomelas can decide on looking for another habitat to reproduce in or staying near the water source itself emerged from.