Identification:
Large crab species, with a carapace width reaching up to 12 cm. The carapace is reddish-brown with a cross-shaped pattern on its surface. The anterolateral margin has six teeth; the first tooth, also known as the outer orbital tooth, curves slightly inward and is slightly concave in the middle. The sixth tooth is directed straight outward, appearing as a spine. The posterolateral and posterior margins are blunt. The frontal margin has six teeth, with the two central teeth being relatively large. The first lateral tooth is broad but slightly shorter than the second.
Biology and Ecology:
Inhabits coastal marine environments at depths of 10-30 meters, preferring rocky, sandy, and coral reef substrates.
Distribution:
- Vietnam: Distributed throughout the coastal waters of Vietnam, but primarily found in the central region.
- Global: Japan, Indonesia, China, Malaysia, Singapore, Thailand, Australia, India, and East Africa.
Value:
Valuable as a food source.
Conservation Status:
Prior to 1975, the species was distributed along the entire Vietnamese coast, but was most commonly found in the central region. After 1975, especially from 1990 to the present, increased fishing pressure has led to a significant decline in the population of the Cross Crab, potentially exceeding 20%. The species’ distribution area is approximately 20,000 km². Due to intense fishing, the distribution area has shrunk to approximately 10,000 km².
IUCN Red List Assessment: VU A1c,d B2a + 3a
Conservation Measures:
This species should be included in the protected species list of the fisheries sector. Furthermore, fishing intensity should be reduced and fishing grounds rotated.