Endangered
Megalagrion pacificum
Megalagrion pacificum
Megalagrion pacificum is a damselfly in the family Coenagrionidae (order Odonata), recorded as Endangered.
Appearance
Adult males and females are both darker in color but can be distinguished by markings on their thorax and abdominal segments. On males, these markings are brick-red while the markings on females are light green.
As adults, Pacific Hawaiian damselflies are roughly 3.3 to 3.8 cm (1.3 to 1.5 in) in length with a wingspan of 3.3 to 4.4 cm (1.3 to 1.7 in). Pacific Hawaiian damselflies are different from other Hawaiian damselflies because of the length of the lower abdominal appendages in the males.
Range and habitat
Due to their lack of flying strength, Pacific Hawaiian damselflies do not often fly far from specific habitats. The Pacific Hawaiian damselfly, Megalagrion pacificum, is a damselfly that is native to Hawaiian streams and wetlands at low elevations. In the last century, the populations of Pacific Hawaiian damselflies have decreased due to invasive species, habitat loss, climate change, stream alteration, and urban development.
Humans introduced nonnative bullfrogs (Rana catesbeiana) to the Hawaiian Islands between 1940 and 1990. Humans introduced another species of frog, Coqui frogs (Eleutherodactylus coqui) to the Hawaiian Islands in the 1980s.
Pins are Wikidata “endemic to” fields. Orange dots, when present, are GBIF occurrence tiles — survey bias included.
Diet and breeding
During this four-month period, naiads feed on small aquatic invertebrates or fish. This species tends to breed in slow-moving water below 610 meters elevation (2,000 feet).
Breeding areas include marshes, small seepage pools, and large ponds that are surrounded by vegetation.
In crisis
Researchers have documented a decline in Pacific Hawaiian damselfly populations since 1905. Nonnative species such as this one are predators that threaten Pacific Hawaiian damselfly naiads. There is correlation between the presence of nonnative fish predation and damselfly population decline.
Bullfrogs are an additional threat to the Pacific Hawaiian Damselfly populations. The lack of governmental enforcement serves as another threat to populations of Pacific Hawaiian damselfly.
Megalagrion pacificum is Endangered on this catalog because that is the IUCN category stored on Wikidata. Confirm the official criteria and any later count on iucnredlist.org.
Sources
Written for this catalog from the English Wikipedia article on Megalagrion pacificum, Wikidata item Q1308079. Family and order context is original field-guide writing about the group, not a copied assessment of this one species. Wikipedia text is CC BY-SA. Not an IUCN assessment. Counts, when quoted, can change — confirm them on the recovery programme and on iucnredlist.org.
