#scarabs

Above: Eusphaeropeltis sp. (top/bottom left) and Ceratocanthus aeneus (bottom right), two different species of pill scarab beetle

Beetles of the Ceratocanthinae subfamily (also known as pill scarab beetles) rely on a unique form of conglobation to conceal themselves. As the beetle tucks its head down and folds its legs up against its belly, the plates on its head, thorax, abdomen, and legs all come together to form a solid shield; the plates on its legs even have grooves and corresponding ridges that allow them to neatly interlock.

As this blog post explains:

Adult Ceratocanthinae are best known for their ability to conglobate: rolling into a nearly perfect ball. The elytra, pronotum, head, and all six tibiae interlock with each other by means of grooves and corresponding ridges, forming a tightly connected external surface. Many beetles take the form of a tight compact structure when threatened, however in Ceratocanthinae the tibiae of all six legs participate in forming the external hard surface of the sphere, unlike in other beetles.

Above: Ceratocanthus sp.

The Ceratocanthinae subfamily contains many different genera/species, and they are all collectively known as pill scarabs. Many of them have a colorful, metallic appearance; they may be green, red, blue, brown, black, or multicolor.

Above: Germarostes globosus

Sources & More Info:

Gil Wizen: Transformers (Ceratocanthinae Beetles)

Communications Biology: The Evolution of Conglobation in Ceratocanthinae

Arthropod Systematics and Phylogeny: Rolling into a Ball: phylogeny of the Ceratocanthinae

ZooKeys: The Ceratocanthinae of Ulu Gombak

SCARAB SCARAB

Egyptian pectoral (jewelry) with a heart scarab and the goddesses Isis and Nephthys on the front and hieroglyphs on the back, identifying the owner as Pyay (royal documents scribe)

ca. 1250 BCE

Today's animal of the day is the Cerulean Chafer Beetle (Hoplia coerulea)!

Photo credit: Anne Sorbes

This absolutely gorgeous species of beetle belongs to the scarab family and can be found in Southwestern European countries, such as France, Spain, and Switzerlands. They prefer somewhat humid environments, such as near swamps or stream. While most people think of the massive rhinoceros beetles or surprisingly strong dung beetles when they think of scarabs, this family of beetles is pretty diverse and contains several subfamilies. The cerulean chafer beetle is part of the Melononthinae subfamily,which includes June beetles, and as such lacks fancy horns and is quite small. However, they're still quite beautiful, and just like their rhinoceros beetle cousins, exhibit some extreme sexual dimorphism. Females are a dull (yet still beautiful) brownish color, while the males are a stunning iridescent blue.

Photo credit: Paul Starosta

Their beautiful coloration makes the males stand out more to predators, and helps them to attract mates since if a male can avoid getting eaten by a bird, rodent, or spider despite not being able to camouflage, then that means he has good skills to pass on to his offspring, and females are more likely to mate with him. Blue is actually a very rare color in nature, and most animals that are blue don't actually have blue pigmentation. In the case of this species, the males are covered in photonic reflective scales, which reflect light to make them appear blue, kind of like blue morpho butterflies. That's also why they look kind of powdery when you look at them up close.

Photo credit: Cristobal Jimenez

Like other types of beetles, they begin life as a larva living within the soil and feeding on roots, buried seeds, and various types of decaying organic matter. Most of this beetle's life is actually spent in their larval stage, and it can spend a year or two underground as a grub. Once they're ready to mature, they'll transform into a pupa and then into their adult form, which only lasts between 3 and 6 weeks. Once they're adults, their diet changes to leaves, flowers, pollen, fruit, and decaying wood, and they'll soon begin searching for a mate. Both sexes will begin congregating in the trees, usually around on that's a food source, in hopes of finding a mate. While most species within the Melolonthinae subfamily are nocturnal, this species seems to be most active during the day, probably since they feed on pollen and most flowers only bloom during the day.

Photo credit: Goliathus on BeetleForum.net