Beutenmüller (1907) described Lasioptera tumifica from stem galls on Solidago rugosa Mill. He actually had a mixed series of 2 species, L. solidaginis (Osten Sacken) and what is here considered A. tumifica...The galls of both species are found near the base of the stems of S. rugosa and S. canadensis [probably incl. S. altissima], but are quite different in structure. The gall formed by L. solidaginis ... is fusiform-cylindrical and is hard and woody, and that formed by A. tumifica ... is an outgrowth of the stem, usually to 1 side of it, and is soft and pithy in texture...

A. tumifica is closely related to Asteromyia modesta (Felt) and can be separated from that species by the larger adult size and shape of the larval spatula...The latter species is found in leaf blister galls...

...A. tumifica is the only one of the 8 species of Asteromyia to be found of woody stems; all the others are found in blister galls on the leaves or green stems of their various hosts.

...tumifica. USA (eastern North America). Solidago rugosa; S. altissima, S. canadensis (Asteraceae).

Lasioptera tumifica sp. nov.

Gall. This is an irregular, rounded, elongate, or kidney-shaped, gnarly, leather-like swelling, usually on one side of the stalk of goldenrod (Solidago rugosa). Sometimes it almost or entirely encircles the stem. It is leathery outside and rather soft and pithy inside, containing many orange larvae. It is found from close to the ground where the roots begin everywhere along the stalk to nearly the middle of the plant, but usually near the lower part. The gall measures from 8 to 24 mm in length and from 5 to 15 mm in width.

Habitat: NY

The larvae transform in the gall and the adults emerge in May.

Asteromyia tumifica (Beutenmüller) is a univoltine species which produces a stem canker on Solidago canadensis Linnaeus. The gall is located near the base of the stem, is polythalamous and the larvae overwinter in the gall. Adults emerge in May.