In contrast to the other two suspected Eleates depressus larvae I found in the Fomitopsis pinicola conk, this one was more of a solid pale color, which indicated to me a sessation of eating in preparation for pupating. It also exhibited the classic abdominal gyrations of a pupa so I assumed the change was imminent. I put it in a small glass vial with a few shreds of conk, primarily as something for it to gyrate against and to absorb any fluids released on eclosure from pupa. (I have found that some provision for absorbtion is necessary or the eclosing beetle's elytra are apt to become stuck to the vial and not fill out as they should.)

In this image you can see the two small tail hooks these larvae have.