Greater Siren
Siren lacertina
The greater siren is a massive, eel-like aquatic amphibian reaching nearly a meter long. Known to aestivate during droughts, it demands a 300L tank, heavily planted with a soft mud or sand substrate.
- Taxonomy
- Class:AmphibiaOrder:CaudataFamily:SirenidaeGenus:SirenSpecies:Siren lacertina
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18 - 26 °C
6.5 - 7.5
Freshwater
100 %
22 °C
18 °C
22 °C
>= 45 L
None
Species description
Care, breeding and tankmates
Geographic Origin and Distribution
Origin
Amphibian profile
- Diet
- Omnivore
- The diet of Siren lacertina consists primarily of appropriately sized prey items found in its natural habitat. In captivity, they should be offered a varied selection of live insects, worms, or small invertebrates to ensure nutritional balance. It is important to gut-load the feeder insects and occasionally dust them with high-quality calcium and vitamin supplements. Monitoring their food intake helps prevent obesity and maintains optimal health. Fresh water must always be available to aid in digestion.
- Life expectancy
- 25-30 years
- The catalog uses 25–30 years as its concise reference range. AmphiBIO v1 instead reports a documented maximum longevity of 25 years for the species. An observed maximum is not the same as a typical expectation: specimen origin, sample size and husbandry conditions can explain differences among sources, so this figure should be read as a recorded limit rather than a promise of survival.
- Adult size
- 97 cm
- The catalog's scalar value is 97 cm. The AmphiBIO v1 source reports a maximum adult measurement of 97.8 cm for this species, recorded as total length (TL). These figures are not interchangeable: the first is the profile's editorial reference, whereas the second is a published maximum under a specific measurement convention; differences among sources can reflect sex, population, life stage and measuring method.
- Lifestyle/Microhabitat
- Aquatic
- Siren lacertina leads a specialized lifestyle adapted to the specific niches of its ecosystem, whether that involves climbing, burrowing, or swimming. Its daily routine is a delicate balance of thermoregulation, seeking out hydration, and avoiding predators. In a captive environment, replicating these microhabitats—such as providing ample climbing branches or deep substrate—is crucial for their well-being. They generally thrive when left undisturbed to carry out their natural routines. A proper setup dramatically improves their lifespan and overall vitality.
- Activity cycle
- Nocturnal
- The activity pattern of Siren lacertina is heavily influenced by the specific light cycle and ambient temperatures of its native range. It may be primarily diurnal, nocturnal, or crepuscular, meaning its peak activity times align with the safest and most optimal conditions for survival. During these active periods, they can be seen exploring, hunting, or patrolling their territory. Careful regulation of the enclosure's lighting and heating schedules will help maintain these natural circadian rhythms. Disruptions to this pattern can cause significant stress or lethargy.
- Sociality
- Solitary
- Siren lacertina is known for its fascinating and unique behavioral traits that reflect its evolutionary adaptations. Observers may notice periods of active foraging interspersed with long spells of resting or hiding. They interact with their environment carefully, using their specialized senses to navigate and detect both prey and potential threats. While some individuals can be quite shy and reclusive, others may exhibit bold and curious behavior when comfortable in their enclosure. Providing a complex habitat with plenty of enrichment is essential for expressing natural behaviors.
- Reproduction
- Oviparous
- Reproduction for Siren lacertina typically follows a seasonal pattern, often triggered by specific environmental changes such as temperature or humidity fluctuations. Mating behaviors can include complex courtship displays or specific vocalizations to attract a partner. After successful mating, the female will carefully deposit eggs or give birth, depending on the reproductive strategy of the species. Incubation or gestation periods require stable, precise conditions to ensure the healthy development of the offspring. Breeders must pay close attention to providing the right nesting environment.
- Toxicity
- Harmless
- Greater Sirens do not produce venom or highly toxic skin secretions for defense. Their primary defense mechanism is their elusive nature and the ability to rapidly swim or burrow away from danger. They do, however, possess a strong bite that can be painful if they are carelessly handled.
- Life stage
- Adult only
- They exhibit paedomorphism, permanently retaining gills and a lack of hind limbs throughout their lives. Despite reaching impressive sizes of up to 38 inches, they never undergo a traditional metamorphosis into a terrestrial form. They spend their entire long lives as aquatic, eel-like amphibians.
- Handling tolerance
- Expert only
- Requires experience to handle, mostly for enclosure maintenance. They are incredibly strong, muscular, and coated in slime, making them prone to injury if dropped.
- Brumation
- Known to aestivate during extreme dry spells by burrowing deep into mud. They tolerate significant temperature drops during winter.
- Molting
- Regular
- Molts occur entirely in an aquatic setting. The shed skin often drifts off in the water column as a sheer, translucent film.
Image gallery
Licensed images linked to the species or, when marked, to the closest representative taxon.
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Variants and close relatives
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