Heterometrus laevigatus

Heterometrus laevigatus is a species of scorpion native to Thailand, commonly referred to as the Thai forest scorpion. It inhabits the humid, tropical forests of Southeast Asia. These scorpions are known for their large size, and their slim glossy black exoskeleton. These scorpions are rare in the otherwise common genus of Heterometrus as they are often mistaken for other Forest Scorpions.

HABITAT

🌍 Geographic Range:

In Thailand, there have been reviews of Heterometrus species which suggest H. laevigatus (or populations formerly assigned to it) occur in southern parts of Thailand, around regions such as the Kra Isthmus.

However, recent taxonomic work (Prendini & Loria, 2020) and also newer papers indicate that the species’ status and exact range are somewhat uncertain, possibly due to confusion or synonymy with similar species.

________________________________

🏡 Microhabitat Preferences:

Heterometrus laevigatus inhabits the warm, humid environments of Southeast Asia’s tropical forests. It is typically found on the forest floor, sheltering under logs, rocks, or leaf litter where conditions remain dark and moist. While not an obligate burrower, it may dig shallow retreats or take advantage of existing crevices and loose substrate.

Physical Description

📏Size:

H. laevigatus can reach lengths of up to 13 centimeters. Typically black and glossy with lots of granulation over it's carapace. Males of this species typically have elongated pedipalps, with both sexes have dark coloured telsons.

________________________________

🎨Coloration:

Generally black and very glossy. Dark brown/black coloured telson from young to adult.

________________________________

Description:

Heterometrus laevigatus are sometimes difficult to identify. They are also similar to Heterometrus longimanus at a glance, except for the fact that they have dark coloured telsons where as H. longimanus have light coloured telsons. The carapace of H. laevigatus is always very granulated.

Captive Care

📏Enclosure Size:

Minimum: 10 litres is plenty for one adult

________________________________

🌡️Temperature:

24–28 °C

________________________________

💧Humidity:

80%.

________________________________

🌱Substrate:

Water-retentive soil

________________________________

⏰Feeding schedule:

Once every week

________________________________

🥣Water Source:

Very important, Hetermetrus species drink a lot of water, water dish must always have water. Overflow water dish to soak the soil around the scorpion, this provides more humidity and allows the scorpion to more easily find the water source.

________________________________

🍃Ventilation

In order to acquire and maintain optimum humidity, you must decrease the ventilation. Too much ventilation such as reptile-like enclosures let out humidity too quickly and allow the substrate to dry out very quickly.

STATS

LATIN NAME:

• Heterometrus laevigatus

________________________

COMMON NAME:

• Thai Forest Scorpion

________________________

TEMPERATURE:

• 24°- 28°

________________________

TEMPERAMENT:

• Will pinch if provoked

________________________

HUMIDITY:

• 80%

________________________

COMMUNAL:

• 4/5

________________________

SIZE:

• Up to 14cm

________________________

ECOLOGY:

• Terrestrial/Fossorial

________________________

SUBSTRATE:

• Water-retentive soil

________________________

ORIGIN:

• Southeast Asia, Philipines

________________________

FACTS

Heterometrus laevigatus has had a complex and shifting taxonomic history. Originally described by Thorell in 1876 as Palamnaeus laevigatus, it was later synonymized with Heterometrus spinifer by Couzijn in 1981 during a broad revision of the genus. This synonymy stood for decades until a major phylogenetic revision by Prendini and Loria in 2020 revalidated H. laevigatus as a distinct species based on detailed morphological data. In that revision, two other speciesL H. cimrmani and H. minotaurus were synonymized under H. laevigatus. However, in 2023, a revision of Heterometrus species in Thailand by Tang and colleagues challenged this view, treating H. laevigatus as a nomen dubium due to doubts about its diagnostic clarity and the uncertain identity of its type material. This study also reinstated H. cimrmani and H. minotaurus as valid, separate species, effectively reversing the 2020 taxonomic consolidations. As a result, the status of H. laevigatus remains disputed, highlighting the need for renewed study of its type specimens and further comparative analyses using both morphological and molecular approaches.