Lasius claviger (Citronella Ant)

Introduction

Lasius claviger, popularly known as the Citronella Ant or the Larger Yellow Ant, is one of the most chemically fascinating species in North America. These ants are famous for the distinct, pleasant lemon or citronella scent they emit when disturbed. This fragrance is a powerful chemical defense mechanism that wards off predators and competitors. For the ant keeper, L. claviger offers a unique sensory experience and a fascinating look into the lives of "social parasites"—ants that start their colonies by infiltrating the nests of other species.

Keeping Lasius claviger is a rewarding challenge for the intermediate to advanced ant enthusiast. They are beautiful ants, featuring a vibrant, golden-yellow to orange coloration that makes them a bright and cheerful addition to any formicarium. Their behavior is a study in subterranean life; they are master excavators and spend much of their time tending to underground "herds" of aphids. With their unique founding strategy, vibrant color, and citrusy aroma, the Citronella Ant is a standout species that adds a layer of chemical wonder to the hobby.

Taxonomy and Distribution

Lasius claviger belongs to the subfamily Formicinae and the subgenus Acanthomyops. This subgenus is characterized by its yellow to orange coloration, reduced eyes (adapted for underground life), and the production of citronellal and citral. The name "claviger" is Latin for "club-bearer," referring to the slightly club-shaped antennae of the workers. They are part of a specialized lineage of Lasius that has evolved to lead a primarily subterranean lifestyle, often in close association with root-feeding insects.

Their distribution is centered in the Eastern and Midwestern United States, ranging from the Atlantic coast west to the Great Plains. They are commonly found in a variety of habitats, including deciduous forests, meadows, and suburban gardens. They prefer well-drained, often sandy or loamy soils, where they can easily construct their extensive network of galleries and chambers. They are frequently encountered by gardeners and homeowners in the spring and fall when their winged reproductives emerge for nuptial flights.

Physical Characteristics

Lasius claviger is a medium-sized ant, with workers typically measuring between 3mm and 5mm. They are monomorphic, meaning all workers are of a similar size, although they may appear slightly different in color depending on their age. The defining physical characteristic is their color: a beautiful, bright golden-yellow or deep orange. This vibrant hue is a hallmark of the Acanthomyops subgenus and makes them exceptionally easy to spot against dark soil or substrate.

The queen is significantly larger and darker than the workers, often measuring 7-9mm. She is typically a dark brownish-yellow or reddish-brown, with a robust thorax and abdomen designed for the energy-intensive task of colony founding. Their eyes are relatively small compared to other Lasius species, reflecting their evolution as subterranean specialists. Their bodies are covered in a fine layer of hairs, and they possess specialized glands in their head and thorax that produce the eponymous citronella scent, which is released when the ant feels threatened.

Colony Behavior and Social Structure

Colonies of Lasius claviger are monogynous (one queen) and can grow to include several thousand workers. They are known for their industrious and organized social life. Much of their activity occurs underground, where they construct complex nest systems. They are highly dependent on "root aphids" and scale insects, which they "farm" on the roots of plants. The ants provide protection and transportation for these insects in exchange for the nutrient-rich honeydew they produce.

Their behavior is generally non-aggressive toward humans, but they are formidable defenders of their nest and their aphid herds. If the nest is disturbed, the workers will release a cloud of citronella scent and swarm the intruder. Socially, they are very cohesive, with a clear division of labor for brood care, nest maintenance, and aphid management. One of the most fascinating aspects of their behavior is their "socially parasitic" founding strategy, where a new queen must infiltrate a nest of another Lasius species (often L. neoniger or L. americanus) and take over the colony by replacing the host queen.

Diet and Foraging

The diet of Lasius claviger is almost entirely focused on liquid carbohydrates, specifically the honeydew produced by subterranean root aphids. This close symbiosis means they rarely forage on the surface. In captivity, they require a consistent supply of high-quality sugar water, honey, or specialized ant syrups. Because they are adapted to underground life, they may be hesitant to forage in an open outworld; placing a feeder near the nest entrance or within a darkened area can help encourage feeding.

Protein is essential for the development of the brood and the queen's egg production. They will accept small insects such as fruit flies, small mealworms, and crickets. In the wild, they likely supplement their diet with small soil invertebrates they encounter while excavating. Providing protein 2-3 times a week is recommended for a growing colony. Because they are not aggressive hunters, pre-killing the insects or providing them in small pieces is often more successful for this species.

Life Cycle and Reproduction

The life cycle of Lasius claviger follows the standard progression of egg, larva, pupa, and adult. Development from egg to adult worker typically takes between 6 and 9 weeks, depending on the temperature. Like all Formicinae, they pupate within silk cocoons. The workers are meticulous in their care for the brood, constantly cleaning them and moving them to the most favorable spots in the nest to ensure optimal growth. The emergence of the bright yellow workers is a highlight for the keeper.

Nuptial flights typically take place in the late summer or autumn, often on warm, humid afternoons. The winged queens and males emerge in large numbers. After mating, the queen must find a host colony of a related Lasius species to begin her own. She will sneak into the host nest, often using her chemical profile to blend in, and eventually kills the host queen. The host workers then raise the new queen's first generation of Citronella Ant offspring, eventually resulting in a pure L. claviger colony. This "host takeover" is one of the most complex behaviors in the ant world.

Environmental Requirements

To keep Lasius claviger thriving, it is important to provide an environment that mimics their subterranean woodland home. They prefer a temperature range of 22-25°C (72-77°F). Humidity is very important for this species, as they are adapted to the stable moisture levels of the soil. The nest area should be kept consistently moist (60-70%), but with a gradient to allow the ants to choose the best spot for their brood. A dark and quiet environment is essential for their sense of security.

Hibernation is a natural and necessary part of their life cycle. From late autumn to early spring, the colony should be kept at a cooler temperature (around 5-10°C). This diapause period allows the queen and workers to rest and ensures the colony's long-term health. During hibernation, feeding should be minimal, but a constant source of water must always be available. Providing a setup that allows for some "subterranean" foraging, perhaps with tunnels or a darkened outworld, can help simulate their natural behavior.

Keeping Lasius claviger as Pets

Lasius claviger is a unique and rewarding species for the intermediate ant keeper. Their beautiful golden color, fascinating "social parasite" biology, and unique citronella scent make them a standout addition to any collection. They are relatively peaceful and easy to manage once the colony is established. While the founding process is complex and usually requires starting with an established host colony or a "boosted" setup, the resulting colony is a beautiful and chemically interesting display of nature's ingenuity. If you want an ant that is both beautiful and fragrant, the Citronella Ant is the perfect choice.

Recommended Habitats

For a beautiful and subterranean-loving species like the Citronella Ant, we recommend the following ANT SHACK habitats:

• All-in-One Desktop Ant Habitat - This habitat is an excellent choice for L. claviger, providing a secure and integrated environment that can be easily kept dark and humid. The integrated outworld allows for easy feeding while maintaining the stable conditions the ants need.
• Ant Habitat “Paris“ - The "Paris" model's horizontal design and high-clarity acrylic are perfect for observing the beautiful golden color of this species. Its modular nature allows you to expand the nest area as the colony grows, ensuring they have plenty of space for their tunnels and brood.
• Natural Ant Habitat Kit - Large - For those who want to create a naturalistic subterranean environment. This kit allows you to use soil and specialized substrates to recreate the forest-floor habitat of L. claviger, providing a healthy and aesthetically pleasing home for your colony.