The species was placed in the genus Euura in 2014 [1] and was previously known as Nematus proximus and Pontania proxima.

[3] Overall, it is described as being cylindrical in shape with a golden brown color, the thickness depending on the developmental stage of the specimen.

[3] The body of adult E. proxima is mostly black with a brown hue, the legs being a lighter, reddish-brown tone.

[4] Mandibulate mouthparts are identified by multiple pairs of appendages coming from two unsegmented mandibles.

The widespread range is due to the spread of its host plants such as Salix alba x fragilis.

[3][14] In New Zealand, the species has been observed in both main islands, covering a wide range of habitat.

[17] Adults tend to come out in spring, during which they begin to search for a suitable willow specimen.

[16] In the Tenthredinidae family, the female continues the life cycle by inserting their ovipositor into the leaf structure.

[16] How galls form is not fully understood; however, there is evidence of chemical induction as well as the involvement of phytohormones.

[22] The larvae initially live in a small opening in the gall; however, it eats through the material until the walls grow thin.

[2][23] The larvae of the species feed on the plant matter provided to them whilst they are enclosed in the gall.