Staphylinidae– The Rove beetles
Instantly recognisable by their thin elongate form and short elytra (wing cases) which exposes the majority of their abdominal segments.
Rove beetles are fairly easy to spot after a bit of practice.
Rove beetles are an incredibly diverse group of beetles, with over 4000 species in the UK alone. Identification is by no means straight forward however it Is possible to quickly lump them into groups with some guidance.
For species level ID, specimens are likely needed and it would be recommended to get in touch with your local beetle recorder for some more in depth knowledge. Due to the size of the group, currently the literature available is somewhat fragmented , but most of the larger species have been covered with some fantastic RES keys.
As a Genus, Paederus are instantly reconisable with their alternating metallic blue/black and red colouring
There are 4 similar species in the UK which can be split into 2 groups by size.
Alternating metallic black/blue and red colouration
A dorsal shot with the pronotum , hind legs and mandibles is recommended to maximise the chance of an accurate ID.
A very distinctive rove beetle that is occasionally found at moth traps
Orange pronotum and elytra
Dark brown abdomen
Nationally Notable B species
One of the largest of our Staphs in the UK. Often referred to as ‘The Devils coach horse’
There are 5 similar species with are on average smaller and lack the matt appearance on the head and pronotum.
Head transverse, appearing sheared off
Filliform Thread like) antennae
Matt appearance to head and pronotum
Year round, but adults are found readily early autumn
Widespread but favours free draining soils
Velleius dilatatus - Hornet rove beetle
RDB1 species and rarely recorded, spending most of its life in hornets nests, until recently populations have been localised.
Night flights are believed to occur when temperatures exceed 16C.
Entirely black/ dark brown
Rounded head with a thick neck
Antenna 4-10 serrate (looking like a saw edge
Large rounded plate like pronotum
Long robust legs
RDB1 species and rarely recorded
Philonthus & Quedius
Two very common, similar looking Genera, their size and general shape are fairly easy to recognise after a while.
Splitting the 2, is largely comparative, however Quedius tends to appear more heavy set and has a thicker ‘bull neck’ when compared to the slimmer, thinner knecked Philonthus.
Both are active fliers and may have rows of punctures on their pronotum which can be used for species identification.
Many require extensive microscopic examination to spit reliably however some can be split with practice in the field
One of the more common Staphs to find on day to day beetle wrangling, so its not surprising it sometimes appears at traps. Luckilly its one of the easy Philonthus to pick out!
P. cognatus's give away is the flash of yellow on the underside of its first antennal segment
40 species, 6 Genera
Small often extremely common staph species with a distinctive tapered ‘tadpole shape’ often dark brown and yellow in colour. Found in all manner of habitats and includes one of the most common Staphylinid species Tachyporus hypnorum (pictured left). Some can be done by external characteristics, but others will require microscopic examination.
Tachyporus is one of the most commonly encountered genera, which there is a key for Here.
Anotylus & Oxytellus
These minute Staphs at a glance seem quite drab, but under a hand lens their true beauty can be seen.
They have a very distinctive semicircle shaped pronotum which has distinctive vertical grooves or ridges. Due to their small size a specimen is usually required for definitive identification.
The two groups are separated by the shape of their pronotum; heart shaped in Anotylus, and diamond shaped in Oxytellus. However,due to the difficulty of seeing this feature, even in prepared specimens, the group is sometimes combined for keying purposes.
In the UK there are 13 species of Anotylus 5 species of Oxytellus
Wide and flat body shape
Often Semicircular pronotum shape
Distinct vertical grooves and furrows on pronotum and sometimes head)
1.2– 5.5 cm