Megalagrion nesiotes | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Insecta |
Order: | Odonata |
Suborder: | Zygoptera |
Family: | Coenagrionidae |
Genus: | Megalagrion |
Species: | M. nesiotes |
Binomial name | |
Megalagrion nesiotes | |
The island of Maui |
Megalagrion nesiotes is a species of damselfly in the family Coenagrionidae. Its common name is flying earwig Hawaiian damselfly. In the past, the flying earwig Hawaiian damselfly lived on the islands of Hawaii and Maui, in the U.S. state of Hawaii. Currently, there is only one population left in east Maui. Limited distribution and small population size make this species especially vulnerable to habitat loss and exotic species invasion. The flying earwig Hawaiian damselfly was last found in 2005. [2] Little is known about this species because of the lack of observation. In 2010, the species was federally listed as an endangered species in the United States. [3]
Adult damselflies have a slender body and fold their wings parallel to the body when at rest. Compared to other damselfly species, the flying earwig Hawaiian damselfly is relatively larger and more elongated. [2] Adults are usually 46–50 mm (1.8-1.9 in) in length. Their wingspan reaches 50–53 mm (1.9-2.1 in). Males are blue and black. They have enlarged and pincer-like abdominal appendages, cerci. The resemblance of the cerci between this species and the earwigs gives this damselfly its common name. Females are primarily brownish. The wings of both sexes are clear except for the darkened tips.
There are no direct records associated with the immatures of the flying earwig Hawaiian damselfly.
Information about the flying earwig Hawaiian damselfly is largely unknown. It is inferred that the life history of this species is like that of some other narrow-winged damselflies in the family Coenagrionidae. [4] As a result, the following life-history traits are from both the flying earwig Hawaiian damselfly and other damselfly species in the family Coenagrionidae.
The flying earwig Hawaiian damselfly is hemimetabolous. It has three life stages: the egg stage, the immature larval stage (naiad), and the adult stage. Flying earwig Hawaiian damselfly adults are weak flyers. They tend to stay on dense vegetation and fly low near the ground. Females may lay eggs on wet banks or in leaf litter near seeps. No direct observation of the naiads is recorded. However, it is proposed that, unlike many other damselfly species that have fully aquatic naiads, the naiads of the flying earwig Hawaiian damselfly are terrestrial or semi-terrestrial. [5] They may live in damp leaf litter or within moist soil or seeps.
Many female damselflies can produce more than one clutch of eggs in their lifetime. They can produce thousands of eggs each time, but the mortality of eggs and naiads is very high. In extreme cases, the survival rate of eggs to adults is only 0-3%. [6]
Damselflies typically reproduce during late spring and summer. [7] They may lay eggs in submerged aquatic plants. [8] It takes about ten days for eggs to hatch. Most naiads of Hawaiian damselfly species are aquatic and predaceous. [9] They have three flattened abdominal gills for breathing, and they feed on small aquatic invertebrates or fish. Naiads may go through 5 to 15 molts as they grow. After several months, they mature and leave the water to become winged adults. For the rest of their life, which usually ranges from a few weeks to several months, they live close to the aquatic habitats and breed there. [10]
Yet, a few other species, including the flying earwig Hawaiian damselfly, have terrestrial or semi-terrestrial immatures. These naiads are usually found in moist leafy habitats on the ground. [11] [12] They have short and stout and hairy gills and are unable to swim. [13] The knowledge about this kind of naiad is limited and needs more research.
The flying earwig Hawaiian damselflies are assumed to be predaceous. [2] Using the diet of narrow-winged damselflies as a reference, scientists suggest that the flying earwig Hawaiian damselfly adults prey on small insects such as flies, mosquitoes, and moths. The immatures have a more aquatic diet including mosquito larvae. [14]
The behavior of flying earwig Hawaiian damselfly was not well-observed. According to patterns of other damselfly species, when mating, damselfly males grasp the females with their abdominal appendages, forming in tandem. This behavior helps defend their mates against rival males. When females lay their eggs, the damselfly males guard their habitats. [15] Breeding of the flying earwig Hawaiian damselfly takes place in leaf litter or damp banks near streams. There are no direct observations on the naiad biology of this species.
When foraging while flying, the adult damselflies use their spiny legs to form a basket to capture prey. For arthropod prey, they often perch themselves and pounce on their prey. [2]
Flying earwig Hawaiian damselfly adults fly low near their habitats. They are not strong flyers, and they prefer to spend time perching among vegetation. [16] Different from aquatic Hawaiian damselfly species, flying earwig Hawaiian damselfly may fly downward when disturbed. They do not fly up and away like aquatic species.
Flying earwig Hawaiian damselfly adults prefer moist areas as habitats. These include wet ridges, forest understory, and steep, fern-covered damp banks. The naiads are believed to live in terrestrial or semi-terrestrial areas, but have never been observed or found. These naiads may occur in leaf litter and plant leaf axils around water, or moist soil between boulders. Flying earwig Hawaiian damselflies are sensitive to temperature changes. They seldom go out on cold and rainy days, while being more active in warm sunny weather. [16] [17]
The flying earwig Hawaiian damselfly used to be found on the tropical islands of Hawaii and Maui. However, since the 1930s, this damselfly has not been observed on Hawaii. The last observation of this species was in 2005 on the island of Maui. [2]
There were at least seven populations of this damselfly on the island of Hawaii, and five populations on the island of Maui. Now there is likely only one population left in east Maui. The last observation of the species was in 2005. [18] No quantitative estimate of the size of this remaining population is available.
In the past, the flying earwig Hawaiian damselfly was on the islands of Hawaii and Maui. In Hawaii, it was known from seven or more general localities. The species has not been seen on Hawaii for over 80 years, however. Surveys within suitable habitats in the Kau and Olaa areas from 1997 to 2008 did not find any of the species. [19] On Maui, the damselfly was historically reported from five general locations on the windward side of the island. [16] Since the 1930s, however, it has only been observed in one area along a stream on the windward side of east Maui.
One of the major threats of this damselfly is habitat loss. [4] It is mainly caused by agricultural and urban development. Currently, global climate changes can also impact the habitat of the species. Stream modifications and diversions could change the surrounding flora, fauna, and prey availability. These changes may degrade the habitat as well.
Nonnative animals, particularly feral pigs, are another major threat. [20] Feral pigs in wet forests on Maui crush the forest floor and lie around in moist areas. These activities remove local vegetation. [21] [22] Their excrement also provides nutrients to invasive plant species. On Maui, the feral pigs have destroyed the uluhe-dominated riparian habitat.
Finally, the overcollection of individuals, especially breeding adults, threatens the damselfly population. [23]
The flying earwig Hawaiian damselfly was petitioned to be listed under the ESA on May 11, 2004.
On June 24, 2010, the U.S. Fish and Wildlife Service determined the endangered status of the flying earwig Hawaiian damselfly under the Endangered Species Act of 1973. This indicates that the species will be given federal protections. [24]
A 5-year review takes all information available of the species at the time of review. The two latest 5-year reviews of the flying earwig Hawaiian damselfly were conducted in 2016 and 2021. [2] No significant new information was discovered.
No Species Status Assessments (SSA's) are currently available for this species.
No final recovery plan for Megalagrion Nesiotes alone is available now.
There is, however, a draft recovery plan for 50 Hawaiian archipelago species. [2] The draft was proposed on February 24, 2022. This document includes the recovery criteria for 3 species of Hawaiian damselflies, including Megalagrion Nesiotes. Megalagrion Nesiotes has a recovery priority number of 5. The goal is to make the species have redundant populations in its historical ranges. Populations should be self-sustaining, resilient, and genetically diverse.
Megalagrion Nesiotes requires systematic surveys and continuous population monitoring. Major strategies include the restoration and protection of species-specific habitats. It is urgent to increase its population size and distribution. Other plans include captive rearing and genetic storage. It is also necessary to control nonnative species. It is important to work with local government and private entities as well.
The downlisting criteria include at least ten stable populations. Suitable habitats for Megalagrion Nesiotes are protected and all significant threats are under control.
The delisting criteria need 10-year surveys. They ask for a significant increase in the size and distribution of the ten populations. Suitable habitats and minimal threats are also required.
Odonata is an order of predatory flying insects that includes the dragonflies and damselflies. The two groups are distinguished with dragonflies usually being bulkier with large compound eyes together and wings spread up or out at rest, while damselflies are usually more slender with eyes placed apart and wings folded together along body at rest. Adult odonates can land and perch, but rarely walk.
Damselflies are flying insects of the suborder Zygoptera in the order Odonata. They are similar to dragonflies but are usually smaller and have slimmer bodies. Most species fold the wings along the body when at rest, unlike dragonflies which hold the wings flat and away from the body. Damselflies have existed since the Late Jurassic, and are found on every continent except Antarctica.
In biology, a nymph is the juvenile form of some invertebrates, particularly insects, which undergoes gradual metamorphosis (hemimetabolism) before reaching its adult stage. Unlike a typical larva, a nymph's overall form already resembles that of the adult, except for a lack of wings and the emergence of genitalia. In addition, while a nymph moults, it never enters a pupal stage. Instead, the final moult results in an adult insect. Nymphs undergo multiple stages of development called instars.
Hemimetabolism or hemimetaboly, also called partial metamorphosis and paurometabolism, is the mode of development of certain insects that includes three distinct stages: the egg, nymph, and the adult stage, or imago. These groups go through gradual changes; there is no pupal stage. The nymph often has a thin exoskeleton and resembles the adult stage but lacks wings and functional reproductive organs. The hemimetabolous insects differ from ametabolous taxa in that the one and only adult instar undergoes no further moulting.
Enallagma cyathigerum is a species found mainly between latitudes 40°N and 72°N; It is widely distributed in the Palearctic, and the Nearctic species Enallagma annexum was at one time considered to be synonymous with it. The species can reach a length of 32 to 35 mm. It is common in many different countries including Russia, Sweden, Norway, Finland, the United States of America, and South Korea. Damselflies are an important link between the health of the aquatic ecosystem and its response to climate change.
The blue-tailed damselfly or common bluetail is a damselfly, belonging to the family Coenagrionidae.
Megalagrion is a genus of damselflies in the family Coenagrionidae. It contains approximately 26 species, all of which are endemic to Hawaiʻi. Megalagrion damselflies are the only native damselflies in Hawaiʻi, and are referred to as "pinapinao" in ʻ ʻŌlelo Hawaiʻi. Other endemic Hawaiian Odonata are the dragonflies Anax strenuus and Nesogonia blackburni, which are referred to as "pinao".
Coenagrionidae or are a family of damselflies, also known as pond damselfies, in the order Odonata and the suborder Zygoptera. The Zygoptera are the damselflies, which although less known than the dragonflies, are no less common. More than 1,300 species are in this family, making it the largest damselfly family. The family Coenagrionidae has six subfamilies: Agriocnemidinae, Argiinae, Coenagrioninae, Ischnurinae, Leptobasinae, and Pseudagrioninae.
The Pseudostigmatidae are a family of tropical damselflies, known as helicopter damselflies, giant damselflies, or forest giants. The family includes the largest of all damselfly species. They specialize in preying on web-building spiders, and breed in phytotelmata, the small bodies of water held by plants such as bromeliads.
Megaloprepus caerulatus, also known as the blue-winged helicopter, is a forest giant damselfly of the family Coenagrionidae. Forest giant damselflies were previously recognized as their own family, Pseudostigmatidae. M. caerulatus is found in wet and moist forests in Central and South America. It has the greatest wingspan of any living damselfly or dragonfly, up to 19 centimetres (7.5 in) in the largest males. Its large size and the markings on its wings make it a conspicuous species; a hovering Megaloprepus has been described as a "pulsating blue-and-white beacon".
Megalagrion adytum is a species of damselfly in the family Coenagrionidae that is endemic to Hawaii. Its natural habitat is swamps.
Megalagrion jugorum is a possibly extinct species of damselfly in the family Coenagrionidae that is endemic to the island of Maui in Hawaii.
Megalagrion leptodemas, commonly referred to as the Crimson Hawaiian damselfly, is one of the rarest and most endangered Megalagrion species that is endemic to the island of Oahu in Hawaii. It is currently labeled as endangered by the ESA and critically endangered on the IUCN Red List. The general biology of Crimson Hawaiian damselflies is similar to other narrow-winged damselflies. Megalagrion leptodemas used to be found in the mountains of Ko’olau and Wai'anae but is now only found in four watersheds in the Ko’olau Mountains. The species is threatened by habitat loss and non-native species. They have limited habitat and small, scattered populations which can affect their future population stability. Conservation efforts for this species should concentrate on both habitat management and control of invasive species.
Megalagrion molokaiense, common name Molokai damselfly, is a species of damselfly in the family Coenagrionidae. It is endemic to Hawaii. Its natural habitat is subtropical or tropical moist montane forests. It is thought that it breeds on dripping wet embankments or in small streams in habitats that lack gambusia.
Megalagrion oahuense is a species of damselfly in the family Coenagrionidae. It is endemic to Hawaii. It is the only known species of odonate with terrestrial nymphs.
Megalagrion oceanicum is a species of damselfly in the family Coenagrionidae that is endemic to the island of Oʻahu in Hawaii. It inhabits rivers in the Waiʻanae and Koʻolau ranges. It is threatened by habitat loss.
The Pacific Hawaiian damselfly, Megalagrion pacificum, is a species of damselfly that is native to Hawaiian streams and wetlands at low elevations. They are predaceous and territorial narrow-winged damselflies that can be identified by their abdominal markings. 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. The species was listed as an endangered species under the Endangered Species Act on July 26, 2010.
The marsh bluet is a damselfly species in the family Coenagrionidae.
Xanthocnemis zealandica, commonly known as common redcoat damselfly, red damselfly, or red coat damselfly, is one of the most common native New Zealand damselflies. Adult damselflies are often seen flying around vegetation close to streams.
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