First described scientifically by American mycologist William Alphonso Murrill in 1912, the species has been juggled by various authors to several genera, including Boletus, Boletellus, and Xerocomus.

Xerocomellus zelleri was first described by American mycologist William Alphonso Murrill in 1912, based on specimens he found on the campus of the University of Washington.

[4] In 1959, mycologists Rolf Singer, Snell and Esther A. Dick transferred the species to Boletellus, explaining that the microstructure of the trama and the faint ornamentation of the spores were inconsistent with placement in Xerocomus.

[7] The specific epithet zelleri was chosen by Murrill to honor Professor Sanford Myron Zeller, mycologist at Oregon State University.

Boletellus chrysenteroides, found only in eastern North America, has a velvety to smooth, dark reddish brown, cracked cap with pale exposed flesh.

[21] The growth form of Xerocomellus zelleri is called gymnocarpic, meaning that the hymenium appears and develops to maturity in an exposed state, not enclosed by any protective membrane.

[22] The mushrooms originate as minute fruit bodies (called "pins" due to their shape) from a yellow mycelium that forms a mat and tends to engulf pine needles.

It differentiates simultaneously into cap and stem along a cleavage plane (an axis along which any cell division occurs) from the outside inward, which gives rise to deep furrow encircling the fruit body.

It is an ectomycorrhizal mushroom, meaning that the fungal hyphae form sheaths around the rootlets of certain trees, exchanging nutrients with them in a mutualistic relationship.

The fungus associates with alder, poplar and other hardwoods,[8] and has been shown in laboratory culture to form ectomycorrhizae with Western Hemlock (Tsuga heterophylla).

[23] However, the fungus may have saprobic tendencies, as it has been noted to grow under California Redwood (sometimes in the rotted wood of old trunks), a tree not known to form mycorrizhae.

Xerocomellus zelleri has been shown to contain the phenethylamine alkaloid compounds tyramine, N-methyltyramine, and hordenine, although the chemotaxonomic significance of this is not clear.