LAGRIINAE Latreille, 1825
Two wooded grassland and scrub species. L. atripes is very local and rare, while L. hirta is widespread and often abundant in the south.
The Lagriinae is a large cosmopolitan subfamily of about 800 species classified into 9 tribes with the greatest diversity in tropical regions. Almost 500 species of about 40 genera have been recorded from the Palaearctic region while there are 35 species and 8 genera in the U.S.A. Europe is particularly poor with only two tribes represented; Laenini Seidlitz, 1895 includes 3 genera and about 270 species of which 2 species of Leana Dejean, 1821 are European, and Lagriini Latreille, 1825, with about 200 Palaearctic species in 28 genera, which is represented by 10 species of the genus Lagria, Fabricius, 1775. The subfamily is represented in the U.K. by 2 species of Lagria. In general appearance the subfamily varies widely in form and colouration with species superficially resembling Cerambycids or Oedemerids e.g. Arthromacra Kirby, 1837, Silvanids e.g. Rhypasma Pascoe, 1862, Chrysomelids e.g. Casnonidea apicicornis Fairmaire, 1887, Carabids e.g. Statira Serville, 1825, and Coccinellids e.g. Paratenetus punctatus Spinola, 1844 which has distinctly clubbed antennae. The species are mostly medium sized, 5-12mm, with the typical characteristics of the Tenebrionidae; 5-5-4 tarsal formula and the antennal bases hidden, sometimes only just so, by an expanded canthus in front of the eyes. The last antennal segment is either the longest or the widest, and often displays sexual dimorphism. The eyes are usually deeply emarginate and often partly encircle the antennal insertions. The head is generally as broad as, or broader than, the pronotum and often constricted behind the eyes. The pronotum is generally much narrower than the elytral base, often broadest across the base and sinuate or variously constricted laterally.
The genus Lagria includes more than 150 species distributed throughout Asia, Africa and Australasia. They are very diverse in appearance with many patterned and metallic species but the general form is much the same as our U.K. representatives. There are 2 subgenera; Apteronympha Seidlitz, 1848 with 3 Western European and Asian species, and Lagria s.str. with 6 European and North African species. Both U.K. species are classified into the latter group and they are very distinctive insects; elongate, flattened and entirely pubescent. The head and pronotum are always dark with long, pale setae and the elytra are weakly sclerotized,
dilated behind the middle and vary from dark brown to almost yellow. The eyes are strongly emarginate and smoothly curved around the antennal insertions. The antennae are always black and pubescent with the long terminal segment sexually dimorphic. The legs are long with narrow femora and tibiae, the basal tarsal segments are elongate; the penultimate segment bilobed below and the claws smooth with a weak basal tooth.
Larger species, 10-12mm. Pronotum with a longitudinal smooth and glabrous area on the disc, the central impression deepened anteriorly. Scutellum black or nearly so and larger than in hirta. Elytral pubescence forming a feathered pattern. Eyes larger and more deeply incised.
Smaller species, 7-10mm. Pronotum entirely strongly and closely punctured, appearing rather mat; the central impression shallow throughout. Scutellum small and only a little darker than the elytra. Elytral pubescence uniform. Eyes smaller and less deeply incised.
Lagria hirta is a very widespread species occurring throughout Europe including Scandinavia, North Africa, and The Middle East and across Russia to East Siberia. In the U.K. it is generally common throughout England and Wales north to South Yorkshire, further north there are scattered records to northeast Scotland. Adults occur from May to late July and may be found in a wide range of habitats including open woodland, grassland and urban gardens etc., they may be very common in areas with light or sandy soils but they also occur in wet areas. They are crepuscular and nocturnal and fly readily, being often attracted to u.v. light, during the day they may be found resting on trunks or walls etc. or in various ‘open’ flowers e.g. daises, yarrow or umbels where they feed upon nectar or pollen. During hot weather they may be seen basking on nettle foliage etc. Eggs are laid in humous-rich soil and hatch after about 8 days. The larvae feed upon decaying vegetation among litter or turf and overwinter, pupating in the soil in the spring. Adults begin to emerge from the soil in May and quickly become common.
L. atripes is also widely distributed although generally local throughout its range, across Europe north to Germany, Belgium and Poland, and east through Iran, Turkey, and Turkmenistan and on to Asia. In the U.K. it is a very local insect with only a few records from East Kent and South Hampshire. The habitats are much the same as for L. hirta and the larvae develop in decaying plant material and leaf litter. Adults occur on low vegetation and flowers etc. The two species are closely similar and may be separated using the above characteristics.
In both species the terminal antennomere is sexually dimorphic; in the male it is about 3 times the length of the penultimate, in the female it is about twice as long. In both the legs are shorter and broader in the female.