Appearance
It is a long-bodied black beetle. At about 20–32 millimetres, it is one of the larger British beetles. Its wing covers are short, covering only its thorax, exposing the abdominal segments.The abdominal musculature is powerful and the abdominal segments are covered with sclerotized plates. It is capable of flight, but its wings are rarely used. It is covered with fine, black hairs. It is well known for its habit of raising its long and uncovered abdomen and opening its jaws, rather like a scorpion when threatened. Although it has no sting, it can give a painful bite with its strong, pincer-like jaws. It also emits a foul-smelling odour, as a defensive secretion, from a pair of white glands at the end of its abdomen.
![Devil's coach-horse (Ocypus olens) [some of the text below was originally written by Patomarazul as a description with this image
https://www.jungledragon.com/image/43321/devils_coach_horse_beetle.html
but that image didn't show the species discussed]
The "Devil's coach-horse beetle" with a length of 20-30mm is one of the largest Rove beetles in Europe. As with other Rove beetles the wing covers (elytra) are short, covering only its thorax, exposing the abdominal segments. The abdominal musculature is powerful and the abdominal segments are covered with sclerotized plates. It is capable of flight but its wings are rarely used. It is covered with fine black hairs. It is well known for its habit of opening its jaws and raising its long and uncovered abdomen, like a scorpion when threatened. This explains one of its alternative names, the cock-tail beetle. Although it has no sting, it can give a painful bite with its strong pincer-like jaws. It can also emit a foul smelling odour as a defensive, through a white secretion from a pair of glands at the end of its abdomen.
Rove beetles (Staphylinidae) are generally hard to identify. It's a large family with many lookalikes for almost all the common species. A larger Ocypus olens (over 25mm) can be distinguished from most others merely by it's size, but you do need to measure not guestimate, as below 25mm there are many more candidates. Still, even for the larger ones, there are a few lookalikes than can reach the same size - most notably Ocypus tenebricosus and O. pedemontanus that also share some of the distribution area.
Also there is some variance in how some authors delimit the genus Ocypus with some groups such as Tasgius or maybe Pseudocypus being either treated as a subgenus or as a genus in its own right. So, especially for the smaller species of Ocypus these need to be considered as lookalikes too.
The image below has a few more perspectives on this specimen, that helped me identify it:
https://www.jungledragon.com/image/48037/ocypus_olens_-_collage.html Coleoptera,Devils coach-horse beetle,France,Geotagged,Ocypus,Ocypus olens,Rove beetle,Staphylinidae,Staphylinini](https://s3.amazonaws.com/media.jungledragon.com/images/3043/48036_small.jpg?AWSAccessKeyId=05GMT0V3GWVNE7GGM1R2&Expires=1716422410&Signature=2jRHueUZfgtMLU61NBmkEErbb3w%3D)
Naming
The Latin species name ''olens'', meaning ''smelling'', refers to the two white stinking glands on the abdomen.This beetle has been associated with the Devil since the Middle Ages. Hence its common name, which has been used at least since 1840. Other names include Devil's footman, Devil's coachman and Devil's steed. It is sometimes also known as the cock-tail beetle for its habit of raising its abdomen.
Subspecies within this species include:
⤷ ''Ocypus olens azoricus''
⤷ ''Ocypus olens olens''
Distribution
These very common and widespread beetles are present in most of Europe and in North Africa. They have also been introduced to the Americas and parts of Australasia.
Behavior
It is a predator, hunting mainly by night, feeding on a range of invertebrates including worms, slugs, spiders, small moths and woodlice, as well as carrion.The prey is caught in the mandibles which are also used to cut and together with the front legs to manipulate the food into a bolus. The bolus is repeatedly chewed and swallowed, emerging covered with a brown secretion from the foregut, until it is reduced to a liquid which is digested. Skin and hard materials are left. The larvae are also carnivorous with similar eating habits.
Habitat
They prefer areas with damp conditions and they can be found from April to October in meadows, heath and moorland, woodlands, hedgerows, parks and gardens. During the day they commonly stay under logs, stones or leaf litter.
Reproduction
''Ocypus olens'' mates in autumn. Females lay their eggs from 2–3 weeks after first mating. They are large and white with a darker band and laid singly in damp conditions under moss, stones, cow pats, or leaf litter.After around 30 days, the eggs split and the larvae emerge, white with a straw-coloured head. The larva lives largely underground, and feeds on similar prey to the adult and has the same well-developed mandibles. It adopts the same display with open jaws and raised tail when threatened.
The larva goes through three stages of growth , the final stage ranging from 20 to 26 mm in length. Around 150 days old, the larva pupates for about 35 days and emerges as an adult with its final colouring, fully formed except for the wings which cannot be folded neatly beneath the elytra for several hours.
Adults can survive a second winter, some by hibernating in burrows and not emerging until March, while others remain active.
References:
Some text fragments are auto parsed from Wikipedia.
