Damselfly

Damselflies belong to the Zygoptera suborder of the Odonata order. They resemble dragonflies, which belong to the Anisoptera suborder of the Odonata, but are smaller and have sleeker bodies. When at rest, most of the species of the damselfly fold their wings along the body. On the contrary,  the dragonflies keep their wings flat and normally away from the body. Damselflies are an ancient group of flies that have been present around since the Lower Permian period and may be found on every continent all over the world except Antarctica. 

The following is a picture of a male and female damselfly:

(Image will be uploaded soon)

Common Characteristics Of Damselflies

Damselflies, both nymphs and adults, are predators that devour other insects. Many different kinds of nymphs live in a variety of freshwater settings. These include the freshwater settings of acid bogs, ponds, lakes, and rivers. The nymphs moult several times before emerging from the water to undergo metamorphosis. They emerge and inflate their wings and abdomen to take on their adult appearance when the skin splits down the back. Their presence on a body of water implies that it is relatively unpolluted, but their need for freshwater renders their wetland habitats vulnerable to destruction.

Some damselfly species have intricate courtship rituals. Many animals are sexually dimorphic, with males being vividly coloured and females being duller. They reproduce similarly to dragonflies, using indirect insemination and delayed fertilisation. The male holds the female at the back of their head, and the female then, in turn, curls her abdomen down in order to pick up the sperm from secondary genitalia present at the base of the male's abdomen, forming a "heart" or "wheel" configuration. The pair often stays together, with the male still clutching the female as she uses a powerful ovipositor to lay eggs in the tissue of plants in or near water. Wet-fly fishing is done with fishing flies that look like damselfly nymphs. Damselflies are frequently used as the inspiration for personal jewellery, such as brooches.

A damselfly has a body layout that is similar to that of a dragonfly. The compound eyes are larger than those of a dragonfly, but they are more widely apart and smaller than those of a dragonfly. The frons, or forehead, is above the eyes, the clypeus is below, and the labrum, an expandable organ used in prey acquisition, is on the top lip. Three basic eyes (ocelli) on the top of the head may assess light intensity, and a tiny pair of antennae may measure airspeed but have no olfactory function. Males of many species are often vividly coloured and identifiable, whilst females are planer, cryptically coloured, and more difficult to identify to species. Males of Coenagrion, the Eurasian bluets, are vivid blue with black markings, whilst females are often green or brown with black patterns. Female-limited polymorphism is seen in a few dimorphic species, with females having two forms, one unique and the other with male-like patterning. Andromorphs, or females who look like men, make up less than a third of the population, but their numbers can climb dramatically, and one idea that explains this response suggests that it aids in overcoming male harassment. Male-limited polymorphism is seen in several Coenagrionid damselflies, a feature that is even less understood. 

Damselflies are smaller than dragonflies in general, with members of the genus Agriocnemis being the tiniest known as wisps. Pseudostigmatidae (helicopter damselflies or forest giants) individuals, on the other hand, are enormous for the family, with wingspans being as large as 19 cms in Megaloprepus and body lengths as long as 13 cms in pseudo Stigma aberrans.

The prothorax, which bears the front set of legs, is the first thoracic section. The slim and flexible connection between the head and the prothorax allows the damselfly to rotate its head and move about more freely while flying. The united mesothorax and metathorax (collectively referred to as the synthorax) are the remaining thoracic segments, each having wings and a pair of legs. The humeral stripe goes from the base of the front wings to the second pair of legs, and the pale-coloured antehumeral stripe runs immediately in front of it.

The forewings and hindwings have a similar look and are membranous, with longitudinal veins that are joined by multiple cross-veins and filled with hemolymph strengthening and supporting them. Species indicators include the pterostigma or stigma, which are quadrangular markings on the wings, and a nodus on the leading edge of almost all species. The flight muscles are housed in the thorax. Many damselflies have transparent wings (e.g., Lestidae, Platycnemididae, Coenagrionidae), whereas others such as Calopterygidae, and Euphoria have coloured wings, either uniformly suffused with colour or clearly marked with a colourful patch. One of the 150 species of the Calopterygidae is the Ebony Jewelwing, also commonly known as black-winged damselfly or black damselfly. The reason it is known as black-winged damselfly or black damselfly is because of the colour of the wings of these damselflies. The male body has a metallic blue-green body with black wings and females have duller brown with smoky wings which gives them a characteristic common name - black-winged damselfly or black damselfly.  Males of species such as Calopteryx splendens have a deeper green body and huge dark violet-blue patches on all four wings, which flutter dramatically during airborne courtship dances; females have pale translucent greenish wings.

The 10 segments of the abdomen are long and slender. Males' secondary genitalia are normally quite visible on the undersides of segments two and three. This makes it easier for determining the damselfly's sex when seen from the side. The female vaginal entrance is located between segments eight and nine on the underside. It may be covered by a subgenital plate or expanded into a sophisticated ovipositor that aids in the laying of eggs in plant tissue. Both sexes have cerci on the tenth segment, and males have a pair of paraproducts on the underside.

Damselflies (excluding the Lestidae spreadwing) usually rest their wings together above their bodies. On the other hand, as mentioned above the dragonflies spread their wings diametrically apart. The L. spreadwing species too spread their wings slightly apart. Damselflies have slim bodies and their eyes do not overlap, unlike dragonflies. Damselfly nymphs are distinguished from dragonfly nymphs by having caudal gills (on the abdomen), whereas dragonflies breathe through the rectum. Damselfly nymphs swim in a fish-like manner, with their gills acting as a tail. For a quick escape, dragonfly nymphs can forcefully discharge water from their rectum.

Where Are They Found?

Except for the continent of Antarctica, odonates can be normally found on every continent. Although some dragonfly species have large distributions, damselflies have narrower ranges. The majority of odonates that usually breed in the freshwater sources, with the exception of a few damselflies of the Coenagrionidae family, which breed in brackish water (and a single dragonfly species breeds in seawater). Pollution has a greater impact on dragonflies than on damselflies. The existence of odonates reflects the health of an ecosystem. There are a variety of acceptable microhabitats in the most species-rich ecosystems, as well as adequate water bodies for breeding.

Although most damselflies spend their entire lives within a short distance of where they were born, some species and individuals within species disperse further. Large male boreal bluets (Enallagma boreale) which are generally present in British Columbia are often known to migrate, but smaller ones do not. Forktails in the family Coenagrionidae appear to be particularly prone to this. These are known to leave their waterside habitats and fly higher until they are lost from view, presumably scattered by the stronger winds encountered at high elevations. This allows them to appear in places where no damselflies had been sighted the day before. Rambur's forktail (Ischnura ramburii) has been discovered on oil rigs in the Gulf of Mexico, for example.

It's worth noting that some species are widespread and can be found in numerous locations. Damselflies are classified into 309 genera and have a total of 2942 species.

Damselfly: The Makeup & Life Cycle

Flies, mosquitoes, and other tiny insects are caught and eaten by adult damselflies. They frequently hover through grasses and low plants, using their spiky legs to pluck prey from stems and leaves. Adults may also utilise smell clues to find their prey, however, they prefer to use eyesight. Although no species is known to hunt at night, some are crepuscular, taking advantage of freshly born flies and other aquatic insects during the roosting season for bigger dragonflies. Helicopter damselflies (Pseudostigmatidae) feed on spiders in tropical South America, hovering around an orb web and pulling the spider or its entangled victim off the web. There are few pools and lakes in these environments, therefore damselflies reproduce in ephemeral water sources such as tree holes, bromeliad rosettes, and even bamboo hollow stems.

Damselfly nymphs have received less attention than their dragonfly counterparts, and many have yet to be discovered. They appear to be less able to overcome larger prey than dragonfly nymphs and pick their food based on size. Crustaceans, such as water fleas, appear to make up the majority of most species' diets.

Damselflies require a variety of habitats in and around wetlands for their larval development, including open spaces for finding mates, suitable perches, open aspects, roosting sites, suitable plant species for ovipositing, and appropriate water quality, and odonates have been used as bio-indicators of ecosystem quality. In terms of water depth, water velocity, and pH, various species have distinct needs for their larvae. For example, the European common blue damselfly (Enallagma cyathigerum) may be found in great numbers in acidic environments where fish are few, such as bog pools. In contrast, the rare blue-tailed damselfly (Ischnura pumilio) demands base-rich environments and slow-flowing water. Ditches, quarries, seeps, flushes, marshes, and pools are all places where it may be found. It can survive high amounts of zinc and copper in the sediment, but it needs appropriate emergent plants to lay eggs without clogging the water. Because damselflies rely on freshwater environments, they are particularly vulnerable to wetlands being drained for agriculture or urban development.

The helicopter damselfly Mecistogaster modesta (Pseudostigmatidae) breeds at a high density of 6000 larvae per hectare in areas of secondary forest in the tropics, in phytotelmata, tiny pools of water held by bromeliads, epiphytic plants of the rainforest of northwest Costa Rica. The cascade damselfly, also known as  Thaumatoneura inopinata (Megapodagrionidae) is a tropical species that live in waterfalls in Costa Rica and Panama. There are many predators that exist who feed on Damselflies. This includes birds, fish, frogs, dragonflies, other damselflies, water spiders, water beetles, backswimmers, and the gigantic water bugs as nymphs and adults.

Internal and external parasites abound in damselflies. The gregarine protozoans present in the stomach are very common. At the peak of the European common blue damselfly's flight season, every adult insect was infected in research. When present in vast numbers, these parasites can clog the stomach and cause death. Hydracarina is normally bright red water mites that can be found on the exterior of both nymphs and adults and can metamorphose from one to the other. They drain the body fluids and can even kill young nymphs, but adults are unaffected because it is necessary for the mite's life cycle to be completed, which is finished when the adult damselfly breeds. 

Many damselflies have complex courtship rituals. These are intended to highlight the male's distinguishing features, like vivid colouration or flying abilities, while also exhibiting his fitness. Calopteryx males hover in front of a female with alternating fast and slow wingbeats; if she is receptive, she will stay perched, but if she is not, she will fly away. The male river jewelwing (Calopteryx aequabilis) flutters his forewings while keeping his hindwings steady and raises his belly to exhibit the white spots on his wings during display flights in front of the female. Male Platycyphas hover in front of females, their dazzling white legs thrusting forward in front of their heads. Platycnemis phasma volans and a few other Platycnemididae species, notably the extinct Yijenplatycnemis huangi, have a flattened tibia and colourful leg colouring. Rhinocypha have been seen to bob up and down, typically low over fast-flowing forested and shaded streams, showing off their coloured bodies that are brightly coloured as well as their coloured wings. Male members of the Protoneuridae family with brightly coloured wings show them off to female visitors. Swift forktail (Ischnura erratica) males show off their blue-tipped abdomens to one another.

Damselflies are hemimetabolous insects that do not go through a pupal stage. The female places the eggs in slits produced in water plants or other underwater substrates with her ovipositor, and the larvae, known as naiads or nymphs, are almost entirely aquatic. The Hawaiian Megalagrion oahuense and an unidentified Megapod Agario Id from New Caledonia are two exceptions, both of which are terrestrial in their infancy. Late in the year, the spreadwings lay eggs above the waterline, and the eggs overwinter, typically covered in snow. They hatch in the meltwater pools in the spring, and the nymphs finish their development before the pools dry up.

Damselfly nymphs are voracious predators, feeding on Daphnia (water fleas), mosquito larvae, and other small aquatic organisms with a flat labium (a toothed mouthpart on the lower jaw) that forms the so-called mask. It is rapidly extended to seize and pierce the Daphnia (water fleas), mosquito larvae, and other small aquatic organisms that damselfly nymphs feed on. They breathe with three enormous, fin-like gills on the apex of their abdomen, which may also serve as the movement in the same way that a fish's tail does. The nymphs have little variety in morphology as compared to dragonfly larvae. They are slim and elongate, with several morphological modifications that allow them to maintain their place in fast-moving water. They are more sensitive to oxygen levels and suspended fine particulate matter than dragonfly nymphs, and they do not bury themselves in the mud.

As they grow, the nymphs go through around a dozen moults. The wing pads become evident in the later stages. The nymphs rise out of the water and establish a firm posture when completely matured, the skin on the thorax separates, and the adult form wriggles out. This creature has a soft body and hangs or stands on its empty larval case at first. It pumps hemolymph into its little limp wings, which fully inflate. The haemolymph is subsequently pushed back into the abdomen, which swells to its maximum capacity. Over the next three days, the exoskeleton hardens and the colours become more vibrant. The majority of damselflies emerge during the day, and the process can take several hours in chilly weather. The cuticle hardens quickly on a hot day, and the adult can be flying away in half an hour.

Cultural Significance of Damselfly

Damselfly is a short film directed by Ben O'Connor and released in 2005. "And that blue there, cobalt / a moment, then iridescent, / frail as a lady's pin / hovering above the nasturtium?" asks August Kleinzahler in his poem "And that blue there, cobalt / a moment, then iridescent, / fragile as a lady's pin / hovering above the nasturtium?" Damselfly, Trout, Heron was included in John Engels' 1983 collection Weather-Fear: New and Selected Poems.

In wet-fly fishing, where the hook and line are allowed to dip below the surface, fishing flies that mimic damselfly nymphs are sometimes used. Since at least 1880, damselflies have been used as motifs for personal jewellery such as brooches. Damselfly is the title of Chandra Prasad's novel, which was released in 2018.

An inspiration for movies and poems, the damselflies have been observed and noted for their beauty. They are also confused many times with dragonflies, both of whom belong to the suborder Odonata. Just like the dragonflies, even the damselflies are also common all over the world. Although, a significant difference can help a person to spot the difference between a dragonfly and damselfly. It is the mannerism in which they keep their wings. A dragonfly keeps the wings straight and apart from the body whereas a damselfly keeps the wings closer to the body. The damselflies are predatory in nature but are not harmful to humans as they do not sting or bite. They are very attractive and hence they use their attractiveness for feeding on mosquitoes and a variety of adult insects thus keeping the insect population in check. In this way, they are helpful to humans in many ways.