Magnacrus

Dominik Alexander
Nov 14
3 min read

Updated: Dec 1

Magnacrus is a newly established genus of Old World tarantulas in the subfamily Ornithoctoninae, formally described in 2025 by Hoang, Yu, Wendt, West & von Wirth. The genus was created after a detailed revision of Asian stout-leg earth tigers showed that Citharognathus tongmianensis (Zhu, Li & Song, 2002) did not belong in Citharognathus; this species was transferred and re-described as Magnacrus tongmianensis, becoming the type species. At the same time, a second species, Magnacrus taynguyenensis, was described from Vietnam’s Central Highlands—these are the spiders hobbyists previously knew as Ornithoctoninae sp. “Vietnam Highland” (and related trade names). Current data indicate that Magnacrus is restricted to montane forest habitats in Vietnam, and earlier records suggesting a Chinese distribution for M. tongmianensis may be based on a mislabelled type locality.

Magnacrus sp. tonogmianensis

Common name: Vendula Earth Tiger (also sold as Vietnam Vendula Thick-Leg Earth Tiger or Lichen Green Earth Tiger).

Origin: Old World earth tiger from tropical forests in Vietnam (with modern taxonomic work indicating it corresponds to the species now placed in the genus Magnacrus).

Lifestyle: Strongly fossorial / terrestrial. This species prefers deep, moist substrate and will construct silk-lined burrows where it spends most of the day, emerging at night to ambush prey at the burrow entrance.

Adult size:

Body length around 5–7 cm
Diagonal leg span roughly 14–17 cm (5.5–6.5") in large females.

Growth rate: Moderate to fast; slings and juveniles put on size steadily under warm, well-fed conditions and reach maturity quicker than most New World terrestrials.

Temperament:

Very fast, secretive, and defensive
Readily retreats to its burrow, but will stand its ground and strike if cornered
Venom is considered strong and bites should be treated as medically significant. This is not a beginner species and is best kept as a display animal.

Color & appearance:

Carapace: metallic golden to olive-gold, often with a subtle sheen
Legs: darker legs with deep green to green-bronze femurs and noticeably thickened hind legs, giving the classic “stout-leg” look
Abdomen: earthy brown with a tiger-like pattern on the underside reported in some lines. Green tones are unusually pronounced for a tarantula, making “Vendula” one of the more visually distinctive earth tigers in the hobby.

Species History

Magnacrus tongmianensis is a recently reclassified Old-World tarantula in the subfamily Ornithoctoninae, family Theraphosidae. The species was originally described in 2002 as Citharognathus tongmianensis by Zhu, Li & Song from Tongmian, Ningming County, Guangxi, China. The type specimens are housed at the Museum of Hebei University in China.

In 2025, Hoang, Yu, Wendt, West & von Wirth created the new genus Magnacrus for two thick-legged earth-tiger tarantulas from Vietnam’s Central Highlands. In that work, Citharognathus tongmianensis was moved into the new genus as Magnacrus tongmianensis, becoming the type species of Magnacrus. The authors also suggested the original Chinese type locality may have been recorded incorrectly, and that verified modern material is from Vietnam rather than China, though catalogues still list the distribution as “Vietnam, China?” pending more data.

In the exotic pet hobby, this spider has had a few different labels over the years. Before the 2025 revision clarified its identity, it was commonly traded as Citharognathus tongmianensis, Ornithoctoninae sp. “Vendula”, and as the Chinese or Vietnamese Stout-Leg Earth Tiger. The 2025 paper and subsequent updates to the World Spider Catalog now standardize the name as Magnacrus tongmianensis, with only two species in the genus: M. tongmianensis and M. taynguyenensis.

Natural Habitat

Magnacrus tongmianensis occurs in warm, humid forest habitats in the Central Highlands region of Vietnam, within the broader South China–Vietnam subtropical evergreen forest belt. It is an obligate burrower, living in deep silk-lined tunnels in compact, leaf-littered soil, and ambushing prey from the burrow entrance. These forests experience consistently high humidity, moderate to warm temperatures, and heavy seasonal rains, with dense ground cover, rotting wood, and thick leaf litter providing stable, cool microclimates underground.

Our Specimen:

Given name: TBD

Sex: Female

Life Stage: Adult