Moved from Lasioptera.

This is within the range of variation of the galls that produced these midges:

Moved from ID Request.

This is a midge gall. There are two options, both Lasioptera species (I’m getting this information from (1)):

L. ephedrae galls are subglobular, nonresinous stem swellings; they each contain one larva; they are dimpled, the same color as the normal stem, and about 10-15 mm long by 5 mm in diameter. The larva feeds along the pith. The pupa is supposed to exit in the spring.

L. ephedricola galls are irregular, resinous stem swellings; they are wrinkled, usually darker than the normal stem, 1-3 cm long, and usually have multiple larval cells. Larvae live in fungus-lined tunnels, and the fungus turns black when mature. Adults emerge February to March.

Neither of these seems like a perfect match; if you still have the gall and can cut it open, that should make things clearer. The different emergence time may mean that the insect that emerged was a parasitoid or inquiline rather than the gallmaker—that could also explain why the gall evidently didn’t develop normally.