Top 20 Most Common Insects in Bulgaria

It is very distinctive with a very broad flattened abdomen, four wing patches and, in the male, the abdomen becomes pruinose blue.

The upperside forewings are a bright orange with a dark outside edge border and with eight or nine black spots. The hindwings are dark with an orange border. Some females also have a row of blue spots inside the orange border and are known as form caeruleopunctata. The undersides are patterned in a similar way but are paler. The black spots on the forewings are outlined in yellow and the dark colouring is replaced by a pale brownish grey. The hindwings are the same brown/grey colour with small black dots and a narrow orange border. The caterpillars (larvae) are usually green, but some have a purple stripe down the middle of the back and along each side.

The meadow brown (Maniola jurtina) is similar to the Gatekeeper in the way that it rests with its wings open due to the "eye spots" on either end of its wings that ward off predators. While the color is a deep brown, the caterpillar form is a beautiful bright green with little, white hairs and a dark line leading down its back.

The Little Sunflower Bläuling (Aricia agestis) is a butterfly (butterfly) from the family Bläulinge (Lycaenidae).

The azure damselfly (Coenagrion puella) is a species of damselfly found in most of Europe. It is notable for its distinctive black and blue colouring. They are commonly found around ponds and lakesides during the summer.

Crocothemis erythraea can reach a length of 3.5 - 4.5 cm. These dragonflies haves a flattened and rather broad abdomen. The adult male scarlet dragonfly has a bright scarlet red, widened abdomen, with small amber patches at the bases of the hindwings. Also the veins on the leading edges of the wings are red. Females and immatures are yellow-brown and have a conspicuous pale stripe along the top of the thorax.

Colias croceus has a wingspan of 46–54 millimetres (1.8–2.1 in). The upperside of the wings is golden to orange yellow with a broad black margin on all four wings and a black spot near the centre forewing. Usually these butterflies settles with its wings closed, consequently the black margin of the uppersides of the wings is difficultly visible. The underside lacks the black borders and is lighter, with a more greenish tint, particularly on the forewings. In the forewing underside is the same dark spot as on the upperside, but often with a light centre; the hindwing underside has a white centre spot, often with a smaller white or dark dot immediately above it. Sometimes, a row of black dots occurs on the underwings' outer margins, corresponding to where the black border ends on the upperside. Females differ from the males in having yellow spots along the black borders on the upperside. In flight, Colias croceus is easily identifiable by the intense yellow colouring, much brighter than that of the lemon-yellow male common brimstone which also lacks black markings. Like all Colias species they never open their wings at rest. In a small proportion of females (about 5%) the golden upperside colouration is replaced by a pale cream colour. These females have been distinguished as form helice. The pale form helice does not seem to be that distinct as intermediates exist and the variation is to some extent related to humidity during development, with dryer conditions producing paler colouration. These pale forms helice can be confused with Berger's clouded yellow (Colias alfacariensis) and the rarer Pale clouded yellow (Colias hyale). Even the palest C. croceus tends to have more black on the upperside however, in particular on the hindwings. Young caterpillars are yellow-green, with a black head. Later they become completely dark green, with a white red spotted lateral line after the third moult. The pupae are green and have a yellow side stripe. This species is rather similar to Colias myrmidone, Colias chrysotheme, Colias erate, Colias hyale, Colias alfacariensis, Colias caucasica, Colias aurorina.

Often confused for the ladybug, multicolored asian ladybeetle (Harmonia axyridis) is a separate species that, unlike the ladybug, is a household pest. It is considered particularly annoying for its habit of returning to places from which it is removed. One of the most variable species in the world, there are many different colors and patterns multicolored asian ladybeetle may display, making identification potentially difficult.

The painted lady is a migratory butterfly that spends part of the year in Northern Africa and then migrates to Europe during the warmer months. Although the adults feed on nectar from flowers, the larvae feed on the leaves of nettles and thistles.

Orthetrum albistylum is a dragonfly species, which occurs from central and south Europe to China and Japan. Its distribution is often patchy but in many areas it is common. The species has recently spread its range northwards to the Baltic Sea coast in Poland. The common name for this species is white-tailed skimmer. One of the ongoing threats affecting the habitat of Orthetrum albistylum is the production of crops. The water pollution associated with crop production is also having a direct effect on the quality of the habitat of this species.