''Sympetrum danae'', the black darter or black meadowhawk is a

dragonfly A dragonfly is a flying insect belonging to the infraorder Anisoptera below the order Odonata. About 3,000 extant species of true dragonfly are known. Most are tropical, with fewer species in temperate regions. Loss of wetland habitat threate ...

found in northern

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, and North America. At about long, it is Britain's smallest resident dragonfly. It is a very active late

summer Summer is the hottest of the four temperate seasons, occurring after spring and before autumn. At or centred on the summer solstice, the earliest sunrise and latest sunset occurs, daylight hours are longest and dark hours are shortest, ...

insect typical of heathland and moorland bog pools. Members of the genus ''

Sympetrum ''Sympetrum'' is a genus of small to medium-sized skimmer dragonflies, known as darters in the UK and as meadowhawks in North America. The more than 50 species predominantly live in the temperate zone of the Northern Hemisphere; no ''Symp ...

'' are known as darters in the UK and as meadowhawks in the US and Canada.

Identification

Both sexes have black legs and

pterostigma The pterostigma (plural: pterostigmata) is a group of specialized cells in the outer wings of insects, which are often thickened or coloured, and thus stand out from other cells. It is particularly noticeable in dragonflies, but present also in ...

ta and a very broad base to the hind wing. The

thorax The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the ...

has yellow sides separated by a bold black panel in which are three yellow spots, resembling a highland darter ('' Sympetrum nigrescens''). The male has a mainly black

and

abdomen The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the tors ...

. The abdomen has small yellow marks on the side, that darken with age. The wings are clear. The female has black legs and brown eyes. The abdomen is mainly yellow, becoming browner with age. It has small yellow patches at the wing bases.

Breeding

This darter is restricted to acidic shallow pools, lake margins and ditches in lowland heath and moorland bogs, usually with bog-mosses and rushes. Eggs are laid in flight by dipping the tip of the abdomen into the water. The eggs hatch the following spring and the larvae develop very rapidly, emerging after as little as two months. Black darters (Sympetrum danae) about to mate.jpg, about to mate Sympetrum danae.ogv, thumbtime=0:17, Males basking in the sun Females tend to choose where to lay their eggs based on the appearance of the site. Female Meadowhawks also base the location of their oviposition on temperature. The females tend to gravitate more towards cooler climates rather than warmer climates. They are also likely to choose an oviposition site that contains little to no predators within the surrounding area.

Population and conservation

In the

British Isles The British Isles are a group of islands in the North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner and Outer Hebrides, the Northern Isles (O ...

, this dragonfly is very locally distributed in the lowlands, but more widespread in the north-west and

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

. It is often very locally abundant and maybe this triggers dispersal. Records from the south coast suggest that immigration from the continent does occur. Its main threats, however, are

development Development or developing may refer to: Arts *Development hell, when a project is stuck in development *Filmmaking, development phase, including finance and budgeting *Development (music), the process thematic material is reshaped *Photographi ...

drainage Drainage is the natural or artificial removal of a surface's water and sub-surface water from an area with excess of water. The internal drainage of most agricultural soils is good enough to prevent severe waterlogging (anaerobic conditio ...

agriculture Agriculture or farming is the practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled peop ...

, and peat extraction.

Diet

The immature Meadowhawk dragonflies feed on a various organisms that can be found in aquatic environments. Some of these insects include fly larvae, mosquito larva, mayfly larvae, shrimp, and other types of fish. The adult Meadowhawks feed on smaller, typically flying insects. Many of their diet consists of insects from the order Diptera. This includes mosquitoes, flies, moth, mayflies, and even insects like mites or termites.

Reproductive structures

One factor that distinguishes the female dragonfly from the male is the presence of two spermatheca, this trait is absent in males. Females also obtain spherical bursa copulatrix. Male dragonflies, on the other hand, possess copulatory organs that aid them during sperm competition. During this process, the males have the capability of removing the sperm of previous mates from the female and replacing it with their own sperm. Males can also be distinguished by their genitalia which is uniquely four-segmented.

Development

The development of the Sympetrum danae is divided into seven different phases. The first phase begins with newly developed eggs. When eggs are first layer they are white in color, but after approximately 18 hours after, they become a grayish color. The second phase takes place four days later when the structure of the yolk alters. It is then followed by the third stage on the eighth days. During this stage the germ plate becomes visible to the naked eye. The fourth stage occurs on the tenth day. This is when segmentation throughout the body becomes noticeable. Then, on the second week the fifth stage occurs. The eyes, mouthparts, and antennae develop during this particular stage. Many days later, on the 189th day, the sixth stage takes place and the embryo flips 180 degrees. Lastly, the seventh stage. This happens on the 197th day and it is when development is complete. The dragonfly typically hatches from its shell 217 days after it was oviposited.

Female v. Male Activity

Meadowhawk males are typically more active in the morning hours. They spent most of their mornings in search of females to mate with. Their activity lessens in the afternoon. Female Meadowhawks are the opposite. They tend to be more dormant in the early hours and more active at night. Male dragonflies are likely to be more active near ponds and bodies of water. Oppositely, females tend to be less active when near the water and prefer to be in areas with overgrown plants and grasses. Female dragonflies typically only go to the water when they are in search of a mate or if they are laying their eggs. Unlike female dragonflies, males have two different types of flight: search flight and patrol flight.