Common Darter — British Dragonfly Society

Common Darter

Description

The most common species of Darter that can be found well into November.

Males: bright orange-red.

Immature males: Pale, yellowish-brown, similar females.

Females: pale, yellowish-brown abdomen often developing red markings with age.

Where to See

Ponds and other still, stagnant or even brackish waters are used, and they are frequently found at small garden ponds.

They are frequently found away from water, resting on the tops of plants in woodland rides.

Abundant in England, Wales and Ireland. Less common in Scotland.

Similar appearance to other Darter species, particularly Ruddy Darter

Common Darter can be separated by its:

  • pale leg stripes
  • black wings spots

british-dragonflies.org.uk

Red dragonfly: description and developmental features of a common European species

The order Odonata contains the dragonflies and damselflies and is one of the most popular insect groups. Odonates are popular with both the amateur and professional because they are large, colorful, easily observable and have exceptionally charismatic behaviors. In recent years dragonflies in particular have been popular with birders as many dragonflies rival birds in wingspan, color, gregariousness, and predictability. As a result of their popularity with the public, they have become the focus of many conservation efforts in North America, Europe, and Asia.

Odonata was until recently composed of three suborders: Anisoptera, commonly known as dragonflies; Zygoptera, commonly known as damselflies; and Anisozyoptera, as the name denotes, a morphological composite of the previous two suborders. However, the suborder Anisozygoptera has been abandoned, as current research shows that Anisozygoptera is not a natural group, and is paraphyletic (Rehn 2003, Lohman 1996). Thus, the group has been combined with the suborder Anisoptera, which does form a natural group in a new suborder called Epiprocta (Bechly 1996). To facilitate the discussion of North American odonates it is useful to use the names Zygoptera and Anisoptera when discussing differences between the damselflies and dragonflies, as there are no extant Anisozygoptera in North America.

Dragonflies (Anisoptera) make up the more specious of the two suborders and are much more easily observed than their dainty relatives, the damselflies. They have large eyes that take up nearly the entire head surface and when not contiguous are not as widely separated as within the damselflies (see the key below). They also have a very robust body structure to support a massive musculature that propels their large, broad wings. Dragonflies are unmatched as fliers and have a very agile, deliberate flight. Males are often territorial, defending oviposition sites from other males.

Figure 1. Dorsal view of an adult dragonfly from the family Libellulidae. Photograph by Seth Bybee, University of Florida.

There are six families of dragonflies found in Florida, each of which is easily identifiable. These insects are commonly found around ponds and open bodies of fresh water and large blacktop parking lots (perhaps parking lots resemble open bodies of water to odonates where they search for prey and mates). There are a number of species that disperse away from water for a time before returning with a mate to breed and deposit eggs.

Damselflies (Zygoptera) comprise the more morphologically diverse suborder of odonates. In North America and particularly in Florida they have similar characteristics, which are: eyes separated by more than the width of a single eye, abdomen much longer than wings, very slim body structure and a simple fluttering flight. Damselflies can often be quite spectacular in color such as the ebony jewelwing damselfly, Calopteryx maculata, found throughout the eastern United States and Florida wherever there are slow flowing, shaded wooded streams.

Figure 2. Dorsal view of an adult Calopteryx maculata, a damselfly. The species is in the family Calopterygidae. This image shows one of two general wing forms found within damselflies in Florida. Photograph by Seth Bybee, University of Florida.

Figure 3. Dorsal view of an adult damselfly from the family Coenagrionidae. This image shows one of two general wing forms found within damselflies in Florida. Photograph by Seth Bybee, University of Florida.

Away from the forest habitat one can find other families of damselflies. One of the most commonly encountered families is Coenagrionidae, which can be observed just about anywhere along the edges of water systems. A less common family of damselflies is Lestidae. This group is readily identifiable in the field by their behavior of perching with their wings held open, a characteristic more common to dragonflies than damselflies.

Distribution (Back to Top)

Odonates are found on every continent except for Antarctica. In particular, the majority of the families that comprise Anisoptera are broadly distributed throughout the world. Some species of dragonfly have vast distributions such as the blue-eyed darner, Rhinoaeschna multicolor, which is found from coast to coast in North America, in addition to Central and South America. In contrast, many families of damselflies are narrowly restricted and several families have an extremely limited distribution.

Florida is home to more than a 150 species of odonates belonging to three families of damselflies: Calopterygidae, Coenagionidae, and Lestidae (Daigle 1991) and six families of dragonflies: Aeshnidae, Cordulegastridae, Corduliidae, Gomphidae, Libellulidae, and Petaluridae (Daigle 1992). They can be seen near any body of water or running stream, often sitting in sunspots breaking through the forest canopy along a river or pond, or patrolling the water’s edge. Some species can be found in open fields far away from water while searching for prey or while migrating.

Description (Back to Top)

Eggs: Odonate eggs display a large array of shapes, from those that resemble tiny rice grains to minute mangos. Odonates oviposit in three ways: endophytic (within a plant), epiphytic (on the surface of the plant), and exophytic (on water or land, Corbet 1999). Generally, eggs oviposited endophytically are several times longer than wide while those laid epiphytically and exophytically are ellipsoidal to subspherical (Corbet 1999). Clutch sizes can be as large as 1500, with some females depositing several thousand eggs in a lifetime (Corbet 1999). Eggs hatch seven to eight days after oviposition but hatching can be postponed for up to 80 days (Miller 1992) and in one case 360 days (Sternberg 1990).

Immature odonates (naiads): Immature odonates are sometimes referred to as larvae or nymphs, but here will be referred to as naiads because odonates are aquatic hemimetabolous (lacking a pupal stage) insects as immatures. Naiads live in most aquatic habitats. Some can even survive in salt water (Corbet 1999). All naiads are voracious predators feeding on everything from small invertebrates such as mosquito larvae to smaller vertebrates such as fish and frogs.

Figure 4. Frontal view of a dragonfly naiad from the family Macromiidae. This image shows the general form of dragonfly naiads. Photograph by Seth Bybee, University of Florida.

Figure 5. Dorsal view of a damselfly naiad from the family Calopterygidae. This image shows the general form of damselfly naiads. Photograph by Seth Bybee, University of Florida.

Naiads will molt nine to 17 times before becoming adults (Corbet 1999). The number of generations per year depends on the species of odonate. Species at higher altitudes or in dry environments usually have one generation per year while those in tropical habitats may undergo multiple generations per year depending on the availability of appropriate habitats.

When naiads are ready for their final molt they leave the water and crawl onto the bank or vegetation where they will molt into adults. Much like a caterpillar emerging from a chrysalis, they need to pump up their wings and allow their bodies to harden before they can be effective fliers. A newly emerged odonate is teneral (soft). A teneral dragonfly has glossy wings and the colors on the body are often pale. Several days after emerging and hardening completely, a dragonfly will have taken on the colors of an adult dragonfly.

Adults: Identifying males and females is not difficult. Males will have what appears to be a pouch on the second and third abdominal segments that contains secondary genitalia. The actual male genitalia are found on the last abdominal segments along with a grasping structure used to hold the female while mating. The male produces sperm at the tip of the abdomen and transfers this sperm to the secondary genitalia where the female will have access to it. Females do not have secondary genitalia or grasping structures at the end of the abdomen but instead have a single genital opening and a small ovipositor at the end of the abdomen that will be used to oviposit her eggs (see above for types of oviposition). Normally, the male dragonfly is more colorful while the female will be a dull brown or grey. This is not true for all odonates. For example, both sexes of Calopteryx maculata are very similar in coloration with the exception of the female having a white pterostigma while the male does not.

When odonates mate they form what is called a «mating wheel.» The wheel is formed when the male grasps the female behind the head and the female raises the tip of her abdomen forward to come in contact with the secondary genitalia of the male. Odonates can often be seen flying in tandem in this fashion.

Adult Key to the Odonate Families of Florida (Back to Top)

1. Head flat in dorsal view, with eyes separated by more than the width of a single eye. Wing venation and wing shape is similar in both fore and hind wings. . . . . . 2 (suborder Zygoptera)
1′. Head round in dorsal view, with eyes touching and making up the majority of the head area. If eyes not touching they are NOT separated by more than the width of an eye. Wing venation and wing shape in fore and hind wings NOT similar. . . . . . 4 (suborder Anisoptera)

2(1). Wings broad with heavy venation and several antenodal crossveins. Wings may be entirely dark or have a red spot at the base of the wing. Larger damselflies found in the forest or shaded areas along running streams. . . . . . Calopterygidae
2′. Wings with a simpler venation, usually clear and only two antenodal crossveins. Generally smaller damselflies found close to pools or lakes, in grasses or along the shoreline. . . . . . 3

3(2′). Veins IR2+ and RP3- arising nearer to the arculus than the nodus. Can be seen resting with wings wide-open hanging from grasses and brush near pools of water. . . . . . Lestidae
3′. Veins IR2+ and RP3- arising nearer to the nodus than the arculus. Can be seen resting with wings closed together over the abdomen. . . . . . Coenagrionidae

4(1′). Eyes touching broadly across top of the head. . . . . . Aeshnidae
4′. Eyes never as above. . . . . . 5

5(4′). Eyes barely touching or touching only at a single point. . . . . . 6
5′. Eyes not touching. . . . . . 9

6(5). Labium with a median cleft. Pterostigma without a brace crossvein. . . . . . Cordulegastridae
6′. Labium not as above. Pterostigma with brace crossvein. . . . . . 7

7(6′). Well developed loop forming a boot shape in hind wing. . . . . . Libellulidae
7′. Loop forming a boot shape but not well developed or loop present but lacking a boot shape all together. . . . . . 8

8(7′). Loop in hind wing forming a boot shape but lacking the cells that make up the «toe» region. . . . . . Corduliidae
8′. Loop present but lacking a boot shape all together. . . . . . Macromiidae

Selected References (Back to Top)

  • Anonymous. (2005). The Dragonfly Society of the Americas. (1 April 2015).
  • Corbet PS. 1999. Dragonflies: Behavior and ecology of Odonata. Comstock Publishing Associates, Cornell University Press. Ithaca, New York.
  • Daigle JJ. 1991. Florida damselflies (Zygoptera): A species key to the aquatic larval stages. State of Florida Department of Environmental Regulation. Technical Series. Vol. 11, Num. 1.
  • Daigle JJ. 1992. Florida dragonflies (Anisoptera): A species kKey to the aquatic larval stages. State of Florida Department of Environmental Regulation. Technical Series. Vol. 12, Num. 1.
  • Lohmann H. 1996. Das phylogenetische system der Anisoptera (Odonata). Deutsche Entomologische Zeitschrift 106: 209-266.
  • Mauffray B. (2005). International Odonata Research Institute. (1 April 2015).
  • Merritt RW, Cummins KW. 1996. An Introduction to the Aquatic Insects of North America (3ed). Kendall/Hunt Publishing Company. Dubuque, Iowa.
  • Miller PL. 1992. The effects of oxygen lack on egg hatching in an Indian dragonfly, Potamarcha congener. Physiological Entomology 17: 68-72.
  • Mitchell F, et al. (2012). Digital Dragonflies. Texas A&M AgriLife. http://agrilife.org/dragonfly/ (1 April 2015).
  • Rehn AC. 2003. Phylogenetic analysis of higher-level relationships of Odonata. Systematic Entomology 28: 181-240.
  • Sternberg K. 1990. Autökologie von sechs Libellenarten der Moore und Hochmoore des Schwarzwaldes und Ursachen ihrer Moorbindung. DrT, Albert-Ludwigs-University, Freiburg Germany.
  • Westfall MJ, May ML. 1996. Damselflies of North America. Scientific Publishers, Gainesville, Florida. 649 pp.

Author: Seth Bybee, University of Florida
Photographs: Seth Bybee, University of Florida
Web Design: Don Wasik, Jane Medley
Publication Number: EENY-355
Publication Date: August 2005. Latest revision: April 2015. Reviewed: October 2018.

An Equal Opportunity Institution
Featured Creatures Editor and Coordinator: Jennifer L. Gillett-Kaufman, University of Florida

entnemdept.ufl.edu

Classification & Distribution

  • incomplete development (egg, nymph, adult)
  • immatures are aquatic (naiads)

Paleoptera

  • primitive wing structure and venation
  • lacking the ability to fold the wings over the back

The Odonata are divided into two suborders:

  • Zygoptera (damselflies) — front and hind wings are similar in shape
  • Anisoptera (dragonflies) — hind wings are broader near the base than the front wings

Distribution: Common in fresh-water habitats worldwide.

Latin Name Sympetrum striolatum
Habitat
Status & Distribution Worldwide
Number of Families
Number of Species

Life History & Ecology

Dragonflies and damselflies are predaceous both as immatures and adults. The adults are quick, agile fliers that are generally considered beneficial because they feed on large numbers of small, flying insects like gnats and mosquitos. Legs are used either as a basket for catching prey or as grapples for clinging to emergent vegetation. Eggs are laid singly in fresh water; females often hover over open water and dip their abdomen as they oviposit.

Eggs hatch into aquatic immatures (naiads) that feed opportunistically on other forms of aquatic life including mayfly naiads, small crustaceans, annelids, and mollusks. Some of the large dragonfly naiads will even attack small fish and tadpoles. All immature Odonata have a specialized labium for catching prey. Folded under the head and thorax when not in use, the labium can be extended rapidly toward potential prey. Hooked lobes at the tip of the labium grasp or impale the prey and draw it back to the mouth as the labium retracts.

Damselfly naiads are usually more slender than dragonfly naiads and have three leaf-like gills at the end of the abdomen. Dragonfly gills are located internally, within the rectum, where bellows-like contractions of the rectal muscles cause oxygenated water to circulate in and out.

Physical Features

Dragonflies

Immatures:

  • Labial «mask» adapted for catching prey
  • Body robust

Adults:

  • Antennae short and bristle-like
  • Compound eyes large, often covering most of the head
  • Four membranous wings with many veins and crossveins
  • Base of hind wing broader than forewing
  • One distinctively pigmented cell (stigma) on leading edge of wing
  • Abdomen: long and slender
See also:  German Cockroach Picture and Description and Cockroach Identification

Damselflies

Immatures:

  • Labial «mask» adapted for catching prey
  • Three leaf-like gills at rear of abdomen
  • Body usually long and slender

Adults:

  • Antennae short and bristle-like
  • Compound eyes large, often covering most of the head
  • Four membraneous wings with many veins and crossveins
  • Base of wings narrow, stalk-like
  • One distinctively pigmented cell (stigma) on leading edge of wing
  • Abdomen: long and slender

Economic Importance

Most dragonflies and damselflies are regarded as beneficial insects because they feed on small flying insects such as mosquitoes. They may also catch and eat honey bees — then they are regarded as pests by the beekeepers.

In some parts of Europe, dragonflies are considered a threat to the poultry industry because they transmit Prosthogoniums pellucidus,a parasitic flatworm. Dragonfly naiads become infected by ingesting cysts of the flatworm. These cysts survive into adulthood of the dragonfly and may spread to birds (particularly poultry) that catch and eat the adult dragonflies. The flatworm cysts dissolve in the bird’s intestine and infection spreads into the cloaca and reproductive organs. The Dutch have a maxim: «Hide the hens, the dragonflies are coming.»

Major Families

      • Aeshnidae (Darners) — These insects are notable for their large size and brilliant blue or green coloration. Includes the common green darner (Anax junius).
      • Libellulidae (Common Skimmers) — This is the largest family in the order. It contains many species with dark spots on the wings.
      • Gomphidae (Clubtails) — These dragonflies have the terminal abdominal segments swollen, hence the common name.
      • Calopterygidae (Broadwinged Damselflies) — The wings of these insects are shaped like the seeds of a maple tree.
      • Coenagrionidae (Narrowwinged Damselflies) — Small, delicate insects. The body is usually black with blue markings. At rest, the wings are held together over the back.
      • Lestidae (Spreadwinged Damselflies) — These damselflies rest with the body nearly vertical and the wings partly outspread.
See also:  What Are the Dangers of the Amazon Rainforest, USA Today

Bug Bytes

  • The compound eyes of some dragonflies may have up to 28,000 facets.
  • Some naiads can shoot out their labium and catch prey in only 25 milliseconds.
  • Scientists have documented large-scale migrations of dragonflies. One swarm was observed 1,400 km off the coast of Australia.
  • Some immature damselflies establish feeding territories, areas that are defended against invasion by other conspecifics. Territorial species develop more rapidly and produce larger adults than other non-territorial species.
  • Many adult male dragonflies establish and defend territories along the perimeter of a lake or stream. Females will mate only with males that hold a territory, so population density is somewhat regulated by territory size.
  • Male Odonata have claspers at the end of their abdomen, but no external genitalia. Before finding a mate, a male attaches a spermatophore to his second abdominal segment. He then grabs a female around the neck with his claspers and she retrieves the spermatophore with the genital opening of her abdomen.
  • Most dragonfly naiads can move forward by «jet propulsion». Rapid contraction of the rectal muscles forces water out the rear end and shoots the insect forward.
  • Male damselflies (and perhaps some dragonflies) have a special flagellum associated with the copulatory organ that can reach into a female’s body and remove sperm deposited by another male in a previous mating.
  • Dragonflies are known by many interesting common names, including «snake doctors», «devil’s darning needles», and «mosquito hawks».

© 2020 by John R. Meyer
Last Updated: 23 January 2020

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Common frog facts for kids

Scientific classification Kingdom: Animalia Phylum: Chordata Class: Amphibia Order: Anura Family: Ranidae Genus: Rana Species: R. temporaria Binomial name Rana temporaria
Linnaeus, 1758 Subspecies
  • R. t. temporaria
  • R. t. honnorati
  • R. t. parvipalmata
Distribution of Rana temporaria in Europe

The common frog (Rana temporaria), also known as the European common frog, European common brown frog, or European grass frog, is a semi-aquatic amphibian of the family Ranidae, found throughout much of Europe as far north as Scandinavia and as far east as the Urals. The farthest west it can be found is Ireland, where it has long been thought, erroneously, to be an entirely introduced species. They are also found in Asia, and eastward to Japan.

Common frogs metamorphose through three distinct developmental life stages — aquatic larva, terrestrial juvenile, and adult. They have corpulent bodies with a rounded snout, webbed feet and long hind legs adapted for swimming in water and hopping on land. Common frogs are often confused with the common toad Bufo bufo, but frogs can easily be distinguished as they have longer legs, hop, and have a moist skin, whereas toads crawl and have a dry ‘warty’ skin.

Contents

Description

The adult common frog has a body length of 6 to 9 centimetres (2.4 to 3.5 in) its back and flanks varying in colour from olive green to grey-brown, brown, olive brown, grey, yellowish and rufous. However, can lighten and darken its skin to match its surroundings. Some individuals have more unusual colouration — both black and red individuals have been found in Scotland, and albino frogs have been found with yellow skin and red eyes. During the mating season the male common frog tends to turn greyish-blue. The average weight is 22.7 g (0.80 oz); the female is usually slightly larger than the male.

The flanks, limbs and backs are covered with irregular dark blotches and they usually sport a chevron-shaped spot on the back of their neck and a dark spot behind the eye. Unlike other amphibians, common frogs generally lack a mid-dorsal band but, when they have one, it is comparatively faint. In many countries moor frogs have a light dorsal band which easily distinguishes them from common frogs.

The underbelly is white or yellow (occasionally more orange in females) and can be speckled with brown or orange. The eyes are brown with transparent horizontal pupils, and they have transparent inner eyelids to protect the eyes while underwater, as well as a ‘mask’ which covers the eyes and eardrums. Although the common frog has long hind legs compared to the common toad, they are shorter than those of the agile frog with which it shares some of its range. The longer hind legs and fainter colouration of the agile frog are the main features that distinguish the two species.

Males are distinguishable from females as they are smaller and have hard swellings, known as nuptial pads, on the first digits of the forelegs, used for gripping females during mating. During the mating season males’ throats often turn white, and their overall colour is generally light and grayish, whereas the female is browner, or even red.

Distribution

The common frog is found throughout much of Europe as far north as northern Scandinavia inside the Arctic Circle and as far east as the Urals, except for most of Iberia, southern Italy, and the southern Balkans. Other areas where the common frog has been introduced include the Isle of Lewis, Shetland, Orkney and the Faroe Islands. It is also found in Asia, and eastward to Japan.

The common frog has long been thought to be an entirely introduced species in Ireland, however, genetic analyses suggest that particular populations in the south west of Ireland are indeed indigenous to the country. The authors propose that the Irish frog population is a mixed group that includes native frogs that survived the last glacial period in ice free refugia, natural post-glacial colonisers and recent artificial introductions from Western Europe.

Newly hatched tadpoles are mainly herbivorous, feeding on algae, detritus, plants and some small invertebrates, but they become fully carnivorous once their back legs develop, feeding on nimals or even other tadpoles when food is scarce. Juvenile frogs feed on invertebrates both on land and in water but their feeding habits change significantly throughout their lives and older frogs will eat only on land. Adult common frogs will feed on any invertebrate of a suitable size, catching their prey on their long, sticky tongues, although they do not feed at all during the short breeding season. Preferred foods include insects (especially flies), snails, slugs and worms.

Habitat and habits

Outside the breeding season, common frogs live a solitary life in damp places near ponds or marshes or in long grass. They are normally active for much of the year, only hibernating in the coldest months. In the most northern extremities of their range they may be trapped under ice for up to nine months of the year, but recent studies have shown that in these conditions they may be relatively active at temperatures close to freezing. Common frogs hibernate in running waters, muddy burrows, or in layers of decaying leaves and mud at the bottom of ponds. The oxygen uptake through the skin suffices to sustain the needs of the cold and motionless frogs during hibernation.

Reproduction

During the spring the frog’s pituitary gland is stimulated by changes in external factors, such as rainfall, day length and temperature, to produce hormones which, in turn, stimulate the production of — eggs in the females and sperm in the male. The male’s nuptial pad also swells and becomes more heavily pigmented. Common frogs breed in shallow, still, fresh water such as ponds, with spawning commencing sometime between March and late June, but generally in April over the main part of their range. The adults congregate in the ponds, where the males compete for females. The courtship ritual involves noisy vocalizations, known as «croaking», by large numbers of males. The females are attracted to the males that produce the loudest and longest calls.

Conservation status

Common frogs are susceptible to a number of diseases, including Ranavirus and the parasitic fungus Batrachochytrium dendrobatidis which has been implicated in extinctions of amphibian species around the world. Loss of habitat and the effect of these diseases has caused the decline of populations across Europe in recent years. The common frog is listed as a species of least concern on the IUCN Red List of Threatened Species.

Predators

Tadpoles are eaten by fish, beetles, dragonfly larvae and birds. Adult frogs have many predators including storks, birds of prey, crows, gulls, ducks, terns, herons, pine martens, stoats, weasels, polecats, badgers, otters and snakes. Some frogs are killed, but rarely eaten, by domestic cats, and large numbers are killed on the roads by motor vehicles.

Images for kids

Common Frog in Norway

European Common Frog or European Common Brown Frog

kids.kiddle.co

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