Temnothorax ravouxi

Temnothorax ravouxi

Temnothorax ravouxi is a small, active slave-making ant (dulosis) native to the Western Palearctic region, ranging from Spain to Turkey and Georgia ^[1]. Workers measure just 2-3mm and are rust-red to brown in color with dense punctures giving them a dull appearance ^[2]. Queens are similarly small at 2.5-3.5mm, unusually tiny for ant queens, earning them the term 'microgynes' ^[3]. This species is one of the most common slave-makers in Western Europe and attacks colonies of various Temnothorax species, primarily Temnothorax unifasciatus ^[4]. Unlike some parasitic ants that are workerless, T. ravouxi produces its own worker caste that conducts well-organized raids to steal pupae from host colonies ^[5]. The species prefers warm, dry, sunny habitats like light forests, rocky areas, and abandoned vineyards ^[3][6].

Quick Summary

• Difficulty: Expert
• Origin & Habitat: Western Palearctic region including France, Germany, Italy, Spain, Hungary, and eastward to Turkey and Georgia. Prefers thermophilic, dry, sunny habitats such as light pine-oak forests, rocky slopes, and abandoned vineyards ^[3][6].
• Colony Type: Monogyne, single-queen colonies. The parasitic queen permanently replaces the host queen in the usurped nest ^[7]. Colonies contain both parasite workers (typically 1-77 workers, averaging 23) and host workers (typically 4-514,averaging 138) ^[7].
  • Colony: Monogyne
  • Queen: Socially parasitic
  • Special: Slave-making
• Size & Growth:
  • Queen: 2.5-3.5mm ^[3]
  • Worker: 2-3mm ^[3]
  • Colony: Typically 100-400 workers total (both parasite and host workers combined) ^[3]
  • Growth: Slow
  • Development: Unconfirmed, likely similar to host species (6-10 weeks based on related Temnothorax) (Brood development can be prolonged with larval hibernation before emergence the following year ^[3])
• Antkeeping:
  • Temperature: Keep at room temperature (20-24°C). As a Mediterranean species, they prefer warmth but can tolerate typical indoor temperatures ^[3].
  • Humidity: Moderate, they inhabit dry, sunny areas. Keep nest substrate slightly moist but not wet ^[3].
  • Diapause: Yes, sexual larvae hibernate in the nest before pupation the following year ^[5]. Provide a cool period (10-15°C) during winter months.
  • Nesting: Small formicarium or test tube setup. In nature they nest in dead branches, under stones, or in hollow twigs, typically small cavities ^[3]. Use materials scaled to their tiny 2-3mm workers.
• Behavior: Temnothorax ravouxi is an active and aggressive slave-maker. Workers conduct organized raids on neighboring Temnothorax colonies, using pheromone trails to recruit nestmates ^[8]. During raids, they fight using their sting, targeting the head or gaster of defending workers ^[3]. They steal host pupae and larvae to raise as slaves in their own colony. Queens enter host nests and slowly throttle the resident queen to death over days or weeks using their mandibles ^[5]. This species is not aggressive toward humans but will sting if handled. Escape prevention is important due to their small size.
• Common Issues: requiring a host species, T. ravouxi cannot survive without Temnothorax workers to serve as slaves, difficulty establishing colonies, queens must successfully usurp a host colony, which often fails, slow colony growth, colonies grow slowly and remain small even when established, host colony death, if the host workers die, the parasite colony will also perish, legal and ethical concerns, this is a protected species in many regions and should not be collected from the wild

Understanding T. ravouxi as a Slave-Maker

Temnothorax ravouxi is an obligate social parasite, it cannot survive without a host colony of Temnothorax ants ^[5]. This makes it fundamentally different from most ant species kept in captivity. The species is monogyne, meaning each colony has exactly one parasitic queen that permanently lives in the usurped host nest ^[7]. The queen does not found a colony independently like typical ants. Instead, after mating during nuptial flights in late August-September, the fertilized queen seeks adoption in an existing Temnothorax colony ^[3]. She enters the nest and slowly kills the resident host queen by throttling, grasping around the neck or throat with her mandibles and squeezing until the host queen dies, which can take days or weeks ^[5][9]. The host workers then accept the parasite queen as their new queen. The parasite colony then relies on host workers to forage, care for brood, and maintain the nest, the parasite workers are relatively inactive and have limited behavioral repertoire ^[3]. This is a permanent parasitic arrangement, not temporary like some other social parasites.

Host Species Requirements

Temnothorax ravouxi parasitizes multiple Temnothorax species, with strong preference for Temnothorax unifasciatus in western Europe (found in 40 of 76 samples in one study) ^[1]. Other hosts include T. affinis, T. nigriceps, T. albipennis, T. tuberum, T. crasecundus, T. nadigi, T. lichtensteini, T. corticalis, T. jailensis, and T. turcicus ^[1][10]. In captivity, you would need to maintain both the parasite and a host species simultaneously. The host colony provides all the essential colony functions, foraging, brood care, nest maintenance, while parasite workers primarily focus on raiding behavior ^[3]. Without a healthy host worker population, the parasite colony cannot survive. This makes T. ravouxi one of the most challenging ant species to keep, as you are essentially maintaining two colonies in one setup.

Slave Raids and Colony Expansion

The most fascinating behavior of T. ravouxi is its organized slave raids. A few scout workers search for nearby Temnothorax colonies. When a scout finds a target colony, she lays a short-lived pheromone trail from her poison gland, leading a group of parasite workers to the host nest ^[8]. The raid typically involves several dozen workers traveling just a few meters, maximum raid distance is approximately 3m ^[8]. During the raid, parasite workers fight defending host workers using their sting, targeting the head or between gastral segments ^[3]. They use venom effectively and can quickly subdue defenders. Once inside, they steal pupae and large larvae, carrying them back to their nest ^[8]. These stolen pupae eclose as host workers, the 'slaves' that will then work for the parasite colony. Male pupae are consumed in the nest while female pupae are allowed to hatch, if new parasite queens hatch, their wings are bitten off to degrade them to workers ^[11]. Raiding typically occurs in early summer (June-July) when parasite workers mature ^[3].

Housing and Care

Keeping T. ravouxi requires maintaining both the parasite and a host species. Use a small formicarium or test tube setup scaled to their tiny 2-3mm size. The nesting area should be small and dark, in nature they nest in dead branches, under stones, or in hollow twigs ^[3]. Temperature should be around room temperature (20-24°C), typical of Mediterranean habitats. Humidity should be moderate, slightly moist substrate but not wet, reflecting their preference for dry, sunny areas. Provide a winter diapause period (10-15°C) as sexual larvae hibernate before pupation ^[5]. The most critical aspect is ensuring a healthy host colony, the host workers do all the foraging and brood care. Feed the host colony standard ant foods (sugar water, small insects). Escape prevention is important due to their very small size, use fine mesh barriers. This species is considered vulnerable or critically endangered in many European countries and should not be collected from the wild ^[12][13]. Captive breeding is extremely difficult due to the complex parasitic lifecycle.

Legal and Ethical Considerations

Temnothorax ravouxi is listed as Vulnerable (VU D2) on the IUCN Red List ^[12][14] and is critically endangered in several countries including Austria (Carinthia) and Germany (Bavaria) ^[15][13]. It is fully protected in Carinthia, Austria ^[13] and protected under various national red lists across its range. This species should NOT be collected from the wild. Captive breeding is exceptionally difficult due to the obligate parasitic relationship with host species. For these reasons, T. ravouxi is NOT recommended for beginner antkeepers, it is an expert-level species that requires specialized knowledge of both the parasite and host biology. If you encounter this species in the wild, observe and document it but leave it in place. The best way to appreciate this fascinating species is through field observation or connecting with researchers studying its behavior.

Frequently Asked Questions

References