Adults are medium to large beetles, they are often brightly coloured and usually densely pubescent, many have metallic colours and contrasting bands across the abdomen, giving the casual appearance of large humble bees, a group they also mimic in their flight behaviour, being able to hover in front of flowers or fly low above the soil in the manner of bees and wasps, giving rise to the common name of Bumble Bee Chafers. They are strong fliers and often swarm about flowers in warm weather, some species may be primary pollinators of certain plants and in certain areas a temporal succession of adults follows the flowering times of various plants. This relationship is sometimes so strong that it is suggested that there is convergent evolution between certain species of Eulasia and Pygnopleurus and a range of red flowers such as poppies and anemones in some Mediterranean regions. Adults are diurnal and spend much of their time flying between flowers where they feel on pollen and nectar and where mating occurs. Females oviposit in the ground and, at least in the few species that have been studied; the free-living larvae feed on roots or buried organic material. Many species are most common in coastal of estuarine areas and larvae often occur in light sandy soils. In the eastern United States Lichnanthe vulpina (Hentz, 1827) is sometimes a pest of cranberries in coastal areas, the larvae developing for up to a year while causing extensive damage to the roots, and the species presence often betrayed by adults swarming about the flowers in the summer.

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6-20 mm. Elongate and typically chafer-like in form although many are narrower and more tapering posteriorly, with small clubbed antennae and long robust legs. Colour very variable both between and within species; mostly testaceous to blue or black, often with the forebody and elytra contrasting and often with various parts bright metallic, some e.g. Glaphyrus maurus (Linnaeus, 1758) are entirely metallic, most with long and dense pubescence to at least part of the body and sometimes the entire body e.g. Pygopleurus vulpes. Head deflexed (at rest), narrower than the pronotum, slightly produced beyond the antennal insertions and with prominent mandibles that protrude beyond the labrum. Clypeus simple or sometimes with teeth on the anterior margin, labrum emarginate, truncate or rounded. Eyes completely or partially divided by a canthus, antennae inserted in front of the eyes, nine or ten segmented with a long basal segment and a three-segmented club. Maxillary palpi four or five-segmented, labial palpi four-segmented. Pronotum quadrate or nearly so; convex, without impressions, tubercles, ridges or horns but usually densely punctured and pubescent. Scutellum exposed and usually small, triangular or U-shaped. Elytra elongate, usually with rounded shoulders and separately-rounded apical margins, without distinct striae. Pygidium and propygidium (at least) exposed beyond the elytral apex. Procoxae conical or transverse, meso- and metacoxae transverse, mesocoxae contiguous or separated. Femora simple, the hind femora often greatly enlarged compared with the others. Protibiae dentate externally and with a single apical spur, meso- and metatibiae simple externally but often with apical spines or emarginations and always with two apical spurs. Tarsi five-segmented and usually simple although in some Palaearctic genera the pro-tarsi are pectinate. Claws paired and equal in length, smooth and with a single basal tooth, empodium flattened and bi-setose. Abdomen with six free sternites and usually with eight pairs of spiracles. Wings always well-developed. Larvae are of typical scarabaeiod form; c-shaped, cylindrical with distinct segments and yellowish or creamy but for the heavily sclerotized head. Ocelli sometimes present, frontoclypeal suture and mandibular stridulatory areas always present, antennae four-segmented, the third segment with small sensory pits. Labrum trilobed, maxilla with separate galea and lacinia, palps four-segmented. Abdominal segments with three dorsal annuli and cribriform spiracles, anal slit transverse and placed dorsally on the terminal segment. Legs robust but lacking stridulatory organs, claws always present.