BUPRESTIDAE Leach, 1815
Strikingly coloured, several of these beautiful, metallic beetles might be encountered in southern woodlands and wooded parklands.
Around the World
This is one of the largest families of the Coleoptera with more than 15000 described species included in about 475 genera. More than 1500 occur in the Palaearctic region, of which about 200 are European. About 750 occur in the United States. By far the greatest diversity is in tropical regions and the majority are thermophilic and heliophilic. The common names refer to the spectacular metallic and iridescent colouration displayed in many species; in south East Asia the elytra of some larger species are used in jewellery on a commercial scale, and ornaments, including large specimens mounted in framed boxes for wall displays, have been produced since Victorian times. Needless to mention they are prized by certain kinds of collectors. To appreciate the diversity of these beautiful insects there are endless very good pictures on line; see below for a few suggestions. The classification remains to be settled e.g. the North American Schizopodinae LeConte, 1859 is often considered as a separate family, but five or six main lineages are thought to represent subfamilies. About half of all known species are included in the Agrilinae Laporte, 1835. The adults vary considerably in size but most are below twenty mm; some Agrilinae are as small as 2mm (Habrolema Spp.) and some of the 75 or so species of Southeast Asian Chrysochroa e.g. C. bicolor (Fabricius, 1778) reach 85 mm. The largest Amazon rainforest species is thought to be Euchroma gigantea (Linnaeus, 1758) at 50-80mm. Several large species e.g. Sternocera orissa Boquet, 1837 are valued as a food source by people in many tropical African countries. Most are characteristically elongate and rather slender but there are many exceptions; species of Trachys Fabricius, 1801 tend to be short and broadly oval while some Madagascan species of the large genus Polybothris Spinola, 1837 (Chrysochroinae Lacordaire, 1857) are rounded laterally with the pronotum and elytra widely explanate, approaching the overall form of Cassida. Many temperate species are brightly coloured and metallic e.g. Anthaxia Eschscholtz, 1829 but to appreciate the real beauty of the group some of the tropical species must be seen, the following examples are all from the Chrysochroinae Lacordaire, 1857. All Southeast Asian species of Chrysochroa Dejean, 1833 are impressive but see C. toulgoeti Descarpentries, 1982 or C. rajah Gory, 1840. New World tropical species of Euchroma Dejean, 1833 are likewise
POLYPHAGA Emery, 1886
BUPRESTOIDEA Leach, 1815
impressive e.g. E. giganteum (Linnaeus, 1758) from Ecuador (etc.). The genus Demochroa White, 1859 includes some spectacular Southeast Asian species but see D. corbetti (Kerremans, 1893). Madagascan species of Madecassia Kerremans, 1903 must be seen, especially M. Rothschildi (Gahan, 1893). Malaysian species of Eucallopistus Bellamy, 2003 are stunning, see E. castelnaudii (Deyrolle, 1864). Such distinctive species are not confined to the Chrysochroinae; among the Julodinae Lacordaire, 1857 the 26 or so Asian and African species of Sternocera Eschscholtz, 1829 are impressive. Among the subfamily Buprestinae Lacordaire, 1857 some members of the genus Calodema Gory & Laporte, 1838 are large and beautiful but also interesting because of the highly modified pronotum e.g. C. ribbei van de Poll, 1885 from New Guinea.
Most species are glabrous but there are many variously pubescent exceptions, compact and well-sclerotized with closely fitting body parts; elongate, rather slender and convex. The general appearance is distinctive and will soon become familiar but some groups resemble members of other families e.g. Lycidae, Dascillidae, Eucnemidae or Elateridae, and some are mimics of Hymenoptera, some Asian species of the enigmatic family Trictenotomidae Blanchard, 1845, which contains about 15 species of large metallic beetles, superficially resemble buprestids. Some contain buprestine, a bitter tasting defence chemical and are mimicked by other insects including beetles. The head is strongly hypognathous and usually transverse, the base being hidden beneath the thorax to the level of the posterior margin of the eyes. The mouthparts are well-developed; the mandibles robust, usually sharp and variously toothed along the inner margin, the labial palps 3-segmented and the maxillary palps 4-segmented with the basal segment very small. Eyes large; sometimes protruding but usually continuous with the outline of the head, usually reniform but sometimes oval or elliptical. Antennae 11-segmented with segments 4-11 developed; serrate or pectinate, sometimes strongly so, and sometimes sexually dimorphic. Pronotum transverse or quadrate, rarely weakly elongate, and usually convex. The anterior and posterior margins are variously developed, beaded or sometimes serrate. The surface is variously sculptured with longitudinal or transverse grooves or ridges, microsculpture, punctures or wrinkles. The anterior margin is usually straight, the posterior margin sinuate or bisinuate, often strongly so, and the lateral margins sinuate or variously constricted. The scutellum is usually obvious; triangular, cordiform or trapezoidal etc. The prosternum is roughly triangular, widening from the pro-coxae to the anterior margin; the posterior process is generally elongate and flat or variously sculptured, the tip rounded or pointed. In some Agrilinae the anterior Prosternal margin is developed into a transverse reflexed lobe. The mesosternum is short and divided by the Prosternal process. The metasternum is large and usually grooved medially. The elytra usually entirely cover the abdomen and in most temperate species are free; but in e.g. Acmaeodera Eschscholtz, 1829-a huge genus of more than 1800 species with an almost worldwide distribution-they are fused and they fly with the hind wings extended beneath the lateral margins of the elytra. They are generally constricted, or at least sinuate, around the level of the hind coxae and the apex may be rounded or variously toothed. The humeri are usually well developed and there is often a transverse or oblique depression near the base. The surface is usually microsculptured, often finely punctured and there may be a larger ground structure consisting of series of parallel ridges, grooves, keels or depressions, the entire surface may be randomly punctured or, especially in some larger tropical forms, there may be deeply impressed and punctured striae. Elytral pubescence, where it occurs, is generally fine but there are densely pubescent species e.g. Acmaeodera. The legs are robust and usually long with enlarged femora and slender tibiae which may have various grooves, ridges, serrations or teeth, and 5-segmented tarsi which often have bilobed segments. Most species have 2 simple claws, sometimes with a basal tooth but there are exceptions; Aphanisticus Latreille, 1829 have only a single claw to each tarsus. The pro- and meso-coxae are round while the meta-coxae are widely transverse, almost reaching the side margin. Most species are fully winged and strong fliers.
Typical Buprestinae larva
Buprestid larvae are typically elongate with the prothorax enlarged and sculpted with elongate grooves, the meso- and metathorax being much narrower and smooth. The head is lightly sclerotized and mostly hidden within the thorax; they are eyeless and have well-developed mandibles. Larvae of this type are mostly wood-borers or develop within the bark of trees and shrubs or occasionally herbaceous plants. These are typical of the majority of genera within the Polycestinae Lacordaire, 1857, Buprestinae Leach, 1815 and Chrysochroinae Laporte, 1835. Larvae of many of the Agrilinae Laporte, 1835 are elongate without the enlarged prothorax and differ from the first type by the presence of sclerotized spines on the terminal segment. The habitats and lifestyles are similar, developing in wood or herbaceous plants. The adults of both types produce the characteristic D-shaped emergence holes which are an excellent sign to the coleopterist of the presence of the family. Larvae of the tribe Tracheini Laporte, 1835 are leaf-miners; the body is parallel-sided with rounded thoracic and abdominal segments and each segment has dark, well- sclerotized plates both dorsally and ventrally and the terminal segment is rounded or conical and without spines. A fourth type of larvae is
seen in the Julodinae Lacordaire, 1857; here the prothorax is only slightly wider than the other segments and lacks the longitudinal grooves seen in the wood-borers. The mandibles are enlarged ventrally with widely-dilated lamellae and the entire body is covered with dense and rather long pubescence. All these features are adaptations to ma subterranean way of life; all species develop in the soil, feeding upon roots or litter.
Adults of most species are thermophilous and heliophilous and may be seen basking or swarming around host material in bright sun although, especially in tropical regions, they may also be, or even exclusively so, crepuscular or nocturnal; they are usually very active, running and flying rapidly and despite their brilliant colours they may be difficult to sample. They are attracted to light and fermenting vegetation, in Australia some are strongly attracted to beer, and in the tropics are often present in trapping samples. Some are strongly attracted to burning wood e.g. some members of the temperate genus Melanophila Eschscholtz, 1829 are attracted to conifer fires and the Australian Merima atrata (Gory & Laporte, 1837) which is attracted to burning eucalyptus, in both cases oviposition on smouldering wood is essential to their development. In both cases the adults resemble charcoal. Both angiosperms and gymnosperms are hosts and species may be monophagous, oligophagous or polyphagous; the wood boring species generally choose damaged or dying parts of otherwise healthy trees. Eggs are usually placed in small groups among the bark etc. and hatch within a week or two. Young larvae feed in the cambium for a while before entering the xylem. There are between three and seven instars and many are univoltine although this varies widely and it is thought that Buprestis aurulenta Linnaeus, 1767 may be
'D-shaped' emergence holes are typical of buprestids.
the longest lived beetle as they have been recorded developing as larvae for more than sixty years. Adults of many species feed on pollen or leaves and may be restricted to the host but are often independent of this, thus many species can be sampled at flowers or by sweeping suitable foliage. Some produce galls on a range of plants e.g. Corylus, Rosa, Fagus, Alnus etc. and some develop in pine cones. Members of the Tracheini Laporte, 1835 e.g. Trachys Fabricius, 1801 and Habroloma Thomson, 1864 are miners in the leaves and stems of herbaceous and woody plants including grasses. Many species develop in herbaceous plants e.g. Agrilus hyperici (Creutzer, 1799) in Hypericum stems, and used as a biological control agent in Australia, while some attack commercially grown hollyhocks e.g. the Palaearctic Trachys troglodytiformis Obenberger, 1918, some Aphantsticus Latreille, 1829 develop in Carex and Juncus stems but this mode of life in less common in temperate regions. One species Habroloma myrmecophila Bilý, Fikáček & Sipek, 2008 has recently been found to be myrmecophilous. Species of the Julodinae develop in the soil, feeding on roots, and the larvae are uniquely adapted within the family. Buprestids are not generally considered to be pest; in large numbers the leaf miners may stunt the growth of individual trees and some stem borers may be a nuisance where the hosts are grown commercially but in forestry generally they are insignificant. An exception may be Agrilus biguttatus (Fabricius, 1777) which has been suggested as the main cause for a recent decline in oaks across Europe. As with any family containing so many saproxylic species they are likely to be transported around the world as a result of the international trade in timber and so exotics are likely to occur just about anywhere.
The classification is difficult to keep up with as there have been many recent changes to the status of higher groups but to follow a very good system see the truly excellent website THE WORLD OF JEWEL BEETLES. The following selective list is an attempt to show some of the larger groups and has also been constructed so that the very limited U.K. fauna can be viewed in some sort of context.
The POLYCESTINAE Lacordaire, 1857 is a worldwide group including 13 tribes, >80 genera and >1500 species.
Haplostethini LeConte, 1861 is a worldwide tribe of 15 genera and more than 700 species.
Acmaeoderini Kerremans, 1893 worldwide; includes more than 500 species of Acmaeodera Eschscholtz, 1829 and about 125 species of Acmaeoderella Cobos, 1955.
Ptosimini Kerremans, 1902 includes 10 species of the Holarctic and Oriental genus Ptosima Serville in Dejean, 1833.
Thrincopygini LeConte, 1861 includes 3 species of the Holarctic and Neotropical genus Thrincopyge LeConte, 1858
Polycestini Lacordaire, 1857 is a worldwide tribe with the greatest diversity in tropical Africa; includes about 100 species in 25 genera.
Tyndarini Cobos includes about 60 Neotropical species in 12 genera.
AGRILINAE Laporte, 1835 is a huge group of more than 7000 species in 200 genera and 4 tribes with a worldwide distribution; the greatest diversity is in the Afrotropical and Neotropical regions.
Agrilini Laporte, 1835 includes about 40 genera and more than 3200 species, about 2900 of which are Agrilus Curtis, 1825 and this is thought to be the largest genus in the animal kingdom. The greatest diversity is in the Neotropics.
Aphanisticini Jaquelin du Val, 1863 is an old world tribe; includes 350 or so species of the widely distributed genus Aphanisticus Latreille, 1829, a single adventive species is now established in the U.S.
Tracheini Laporte, 1835 is a worldwide group of about 2000 species in 11 genera. Trachys Fabricius, 1801 includes about 650 old world species, a few of which have been introduced to the Nearctic region.
CHRYSOCHROINAE Laporte, 1835 includes about 2700 species in 110 genera and 8 tribes.
Chrysochroini Laporte, 1835 is a worldwide group of about 750 species in 50 genera.
Dicercini Gistel, 1848 occurs worldwide with the exception of Australasia, contains about 770 species and 30 genera.
BUPRESTINAE Leach, 1815 is a very diverse group of about 3300 species in 120 genera and 20 tribes. Some tribes include localized and unique groups e.g. the New World Phrixiini Cobos, 1975 and Xenorhipidini Cobos, 1986, each of which include 3 genera.
Buprestini Leach, 1815 Occurs worldwide except in Australasia; about 120 species in 8 genera including 80 species of the Holarctic and Oriental genus Buprestis Linnaeus, 1758.
Anthaxiini Gory & Laporte, 1839 includes 10 genera and more than 900 species worldwide except in Australasia. The genus Anthaxia Eschscholtz, 1829 has more than 700 species.
Chrysobothrini Gory & Laporte, 1838, a worldwide group of more than 770 species in 6 genera. The genus Chrysobothris Eschscholtz, 1829 includes about 700 species.
Melanopthalini Bedel, 1821 includes about 50 species in 6 genera; they occur worldwide except for the Neotropical region, and only a single species occurs in Australia.
Stigmoderini Lacordaire, 1857 includes about 500 species of the genus Castiarina Gory & Laporte, 1838, which occur only in Australia and New Guinea. Many are stunningly beautiful beetles and many have a brief season, timing this with the flowering of their host plants.
JULODINAE Lacordaire, 1857 includes 6 genera which are widely distributed except for the Neotropical region.
The Schizopodidae LeConte, 1859 was formerly included as a subfamily, the species now being known as false jewel beetles. They superficially resemble buprestids but have the fourth tarsomere deeply bilobed and the metepisternum widened. They are Nearctic and mostly desert-living species where the larvae are soil-living root-feeders. There are 7 species in 3 genera.
The U.K. fauna is poor even by northern European standards; our latest checklist (2012) includes 17 species in 5 genera representing 2 subfamilies, and of the 200 or so European species about 50 occur in the north. Three of our species have been added since the previous checklist (2008), and Anthaxia nitidula (Linnaeus, 1758) is now thought to be extinct while Aphanisticus emarginatus (Olivier, 1790) has not been recorded in recent decades. Melanophila acuminata (De Geer, 1774) may only occur as occasional specimens from the continent. About 10 species have been recorded as non-established introductions and Buprestis aurulenta Linnaeus, 1767 is occasionally introduced with timber imported from America. Our species are mostly confined to the southeast of England. Two species, Agrilus laticornis (Illiger, 1803) and A. angustulus (Illiger, 1803) are local but widespread in the southeast and might be expected from sampling oak and other broadleaved trees in the summer. There is no work dealing with our entire fauna although the very useful handbook by Levey (1977) is available online and Mike Hackston’s online key has expanded this to include all our species. Bíly (1982) includes all our species except Agrilus sinuatus (Olivier, 1790) but is nonetheless worth obtaining as it includes a great deal of information on the family. All our Agrilus species have been keyed by Théry (1942) in the Fauna de France series which is available online.