Schizotus pectinicornis (Linnaeus, 1758)
Scarce Cardinal Beetle
POLYPHAGA Emery, 1886
TENEBRIONOIDEA Latreille, 1802
SCHIZOTUS Newman, 1838
This is the most widespread European member of the family, it occurs locally throughout almost the entire continent, in the south mostly in mountainous regions otherwise locally common to the far north of Scandinavia and extending east into Russia. Here it is a very local species of the Scottish Highlands around Inverness, there are older records from the Welsh Borders but it is now thought to be confined to the highlands. Adults have a short season, from April to mid-June although at higher continental latitudes they occur into July and have been recorded in September, the typical habitat is deciduous woodland where the adults may be seen on low herbaceous vegetation or fallen timber, they are active in bright sun and disperse by flight although they rarely occur far from their breeding sites. Mating occurs early in the season when pairs may be seen in cop. running across fallen timber. Females oviposit during May, eggs are laid in small batches among the bark on trunks or recently fallen broadleaf timber, more rarely on coniferous trees, mostly oak, birch, willow and alder. Larvae develop beneath bark feeding on organic detritus and dead insects etc. they also predate other subcortical larvae and at high densities may become cannibalistic, development takes at least two years and they generally occur in numbers, often with members of two generations occurring together. They become fully grown in the spring, by this time their habitat has accumulated a layer of compost which they use to construct a pupal cell beneath the bark, pupation occurs during February or March and adults eclose within a few weeks, they remain in the cell for a week or two to harden and become pigmented and emerge from the bark during the first warm spells of April. All stages contain the poison cantharidin, it is present in and probably synthesized by the males and passed to females during courtship, she will then transfer it to the eggs during oviposition and the larvae are thought to acquire it by consuming the eggshells.
Adults are smaller, 7-9mm, compared with our other pyrochroids and usually have a distinctive black mark on the pronotal disc. The antennae are distinctive among our other red-coloured beetles, strongly pectinate in the male but much less so in the female. The distribution is also a good indication as no other red-coloured species is sympatric with Schizotus.
Schizotus pectinicornis 1