[1] Like other Euwallacea species beetles, E. validus is known for its mutualistic symbiotic relationship with fungi, acting as a vector for Fusarium oligoseptatum and Raffaelea subfusca, often using Tree of Heaven (Ailanthus altissima) as a preferred host.

[1] Both species have overlapping habitats in the United States, mostly in Georgia and South Carolina, leading to frequent misidentification.

[1] Morphologically, E. interjectus and E. validus can be differentiated by slight differences in the shape of declivity, punctures, and placement of tubercles on the body of the species.

[5] E. validus and the Euwallacea species are known for their pronotum, a plate-like structure that acts protection near the thorax, and spindles that cover a beetle's body.

[5] Euwallacea validus was first discovered in Nassau County, New York in 1975 and is assumed to have spread throughout the eastern United States, as the beetles were collected repeatedly from widely separated localities.

[1] It is also believed that the species entered the United States from wooden packing crates from Japan at various ports.

[6] Euwallacea validus females are critical in the symbiosis with F. oligoseptaum and Raffaelea subfusca by dispersing the fungi between host trees.

[10] Given their reduced musculature, suggesting a similar reduction in chewing strength, their role in the gallery is reproduction and potential fungal maintenance.

[10] Research has shown the development of both superior mycangia and inferior structures in the late pupal stages of females.

[11] Female Euwallacea beetles transfer their fungal associates in their mandibular mycangia, from their natal gallery to hosts.

[12] Euwallacea validus has a mutualistic symbiotic relationship with fungi of the Ambrosia Fusarium clade (AFC).

[7][12][11] Phylogenetic analysis of the Ambrosia Fusarium Clade and Euwallacea species found evidence of repeat host shifts rather than stretches of coevolution or mutualism.

[13] Euwallacea species and their fungal associates are known to cause canker incidence and overall damage to their plant hosts.

[2] E. interjectus host plants are crucial to the lumber industry, and E. Fornicatus elicits disease on avocado trees in California and Israel.

[2] Other known AFC lineages that are present in the US were uncovered from the mycangia of other Euwallacea species within the geographic origin of beetles in East Asia.

[2] R. subfusca, E. validus's second symbiont, is unique to the species, and the fungus is found in equal proportion to Fusarium sp.

[2] When the spring season begins, beetles may emerge and find a suitable host to establish natal galleries.