Taxodiomyia taxodii
(Felt, 1911)
cypress leaf gall midge, cypress twig gall midge
A gall midge in the Cecidomyiidae that induces distinctive galls on cypress trees. are tiny flies that lay in cypress tissues, with larvae developing inside spongy, globular galls that initially appear snow-white and turn brown with age. The species is closely related to Taxodiomyia cupressiananassa, which produces similar galls on bald cypress.


Pronunciation
How to pronounce Taxodiomyia taxodii: //ˌtæksəˌdaɪˈoʊmiə tæksˈoʊdi.aɪ//
These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.
Identification
Distinguished from other cypress-feeding gall midges by its association with Taxodium and the characteristic globular, spongy galls it produces on twigs. Galls begin snow-white and darken to brown as they mature, eventually dropping from the tree with shed leaves. The fly is minute and unlikely to be observed directly; identification relies on gall and association.
Images
Habitat
Associated with cypress trees (Taxodium ), particularly in wet or mesic environments where these trees occur. The species has been observed in restored prairie areas and conservation lands with planted cypress trees.
Distribution
Documented from Missouri and likely occurs wherever cypress trees are present in suitable . The related T. cupressiananassa has been recorded in southeastern Missouri and as far north as Callaway County where planted bald cypress trees occur.
Seasonality
emerge from galls in late season; larvae overwinter inside fallen galls and pupate, with adults emerging the following spring. Galls are visible on trees from formation through leaf fall.
Diet
Larvae feed internally within cypress galls. Specific feeding habits of are unknown but typical for Cecidomyiidae involve nectar or not feeding at all.
Host Associations
- Taxodium distichum - bald cypress
- Taxodium - cypress
Life Cycle
female lays in cypress twig tissue. Larvae hatch and induce gall formation through secretion of plant growth-like , creating a spongy, globular structure. Larvae develop inside the gall, pupate, and adults may emerge from galls still on the tree later in the season. Alternatively, galls drop with leaves and larvae overwinter inside fallen galls, completing development and emerging as adults the following spring.
Behavior
Larvae manipulate plant growth to create protective galls. are short-lived and focused on . The is parthenogenetic or has a complex typical of gall midges with alternating .
Ecological Role
As a gall inducer, creates microhabitats that may support or . Represents a component of cypress-associated .
Human Relevance
Minor significance; galls may be mistaken for fungal or cones by observers. Serves as an example of insect-plant interaction for educational purposes.
Similar Taxa
- Taxodiomyia cupressiananassaAlso produces globular, spiky galls on cypress twigs; distinguished by taxonomic separation and potentially subtle differences in gall and specificity
- Gymnosporangium juniperi-virginianaecedar-apple rust fungus produces visually similar spiky galls on Juniperus; distinguished by being a fungus rather than insect, and by (Juniperus vs. Taxodium)
Sources and further reading
- BugGuide
- GBIF taxonomy match
- iNaturalist taxon
- Catalogue of Life
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