top of page

Platycerus caraboides

(Linnaeus, 1758)

Blue Stag Beetle 

Suborder:

Superfamily:

Family:

Subfamily:

Tribe:

Genus:  

POLYPHAGA Emery, 1886

SCARABAEOIDEA Latreille, 1802

LUCANIDAE Latreille, 1804

LUCANINAE Latreille, 1804

PLATYCERINI Oberth, 1913

Platycerus Geoffroy, 1762

This widely distributed Palaearctic species occurs throughout Europe from Portugal north to southern Scandinavia and east through Russia to Siberia and northeast China, further south it is widespread across North Africa; Morocco, Tunisia and Algeria etc. and the Middle East, although it is absent from much of southern Spain and large parts of Greece and the Balkans. In the U.K. there is fossil evidence of its presence up until the bronze age and there are a few, not always convincing, records from the early decades of the nineteenth century from near Oxford, Windsor and possible Bristol, and there is an old, unconfirmed record from Scotland (south Aberdeenshire). On the continent it is a local and generally rather common species of broadleaved and mixed woodland and wooded areas at lower elevations, generally up to 750m although in some areas e.g. in extensive beech woods in the Apennine Mountains of central Italy, it shows a preference for higher level forests. Adults occur from May to July; they are diurnally active and tend to keep low down on logs and fallen timber or on decaying parts of standing trees but in hot weather they climb up onto small branches to feed on fresh leaves and buds and they readily take flight, hence they are often recorded flying along wooded margins of in clearings and wooded parkland etc. The larvae develop among white rotten wood in a wide range of broadleaved trees but perhaps more especially in oak, beech and hornbeam, and they have also been recorded from pine; development takes 2 or 3 years with pupation occurring in late summer or autumn; adults eclose in the autumn but remain in the pupal cells until the following spring.

​

9-13mm. Distinguished among the U.K. fauna from Lucanus and Dorcus by the metallic colouration and the uninterrupted eyes, and from Sinodendron by the much flatter form; in any case these 4 species are obvious but on the continent caraboides will generally need to be dissected to separate it from the closely similar P. caprea (DeGeer, 1774). Adults are shiny metallic blue-black or green-black with black legs which are often to some extent red. Head quadrate with long, almost parallel, temples and a widely and deeply emarginate anterior margin, the vertex is  weakly convex, becoming flat or weakly concave in front 

of the eyes, the surface strongly and quite densely punctured. Mandibles robust, protruding and have a large bi-tuberculate tooth at the base. The eyes are entire, circular and weakly convex. Antennae relatively long; the scape long and curved and the club 3-segmented and broad. Sexual dimorphism is not so developed as in most other stags; males have larger mandibles and a wider antennal club. Pronotum transverse, more so in the male, broadest behind the middle and with all margins strongly bordered, anterior angles protruding and lateral margins sinuate before almost perpendicular hind angles, basal margin straight. Pronotal disc only weakly convex and the punctation is similar to that on the head. The elytra are weakly broadened behind the middle with an explanate margin from the basal third to the apex, punctation strong and rather dense; mostly random but tending towards striae on the disc. Legs long and robust; pro-tibiae toothed externally, meso- and meta-tibiae with a strong spine on the inner apical angle. Tarsi 5-5-5, without lobed segments, the basal pro-tarsomere is often hidden under the apex of the tibia. Claws long and curved, without teeth, the bi-setose empodium distinct

bottom of page