Conifer-parasite
Guides
Thecodiplosis brachynteroides
Thecodiplosis brachynteroides is a species of gall midge in the family Cecidomyiidae, described by Osten Sacken in 1862. Gall midges in this family are small, delicate flies whose larvae induce gall formation on host plants. The genus Thecodiplosis is associated with conifer hosts, particularly pines.
Trisetacus
Trisetacus is a genus of eriophyoid mites (Eriophyoidea: Phytoptidae, historically placed in Nalepellidae) that are obligate parasites of coniferous trees. Species within this genus exhibit strong host specificity, primarily infesting members of Pinaceae and Cupressaceae. The genus includes species with diverse feeding habits: some inhabit needle sheaths, others infest foliage, buds, or seeds. Molecular phylogenetic studies have revealed a deep dichotomy within Trisetacus, with two major lineages distinguished by female genital morphology and host associations—one lineage associated with Pinaceae and another with Cupressaceae. Several species are significant forest pests, causing damage ranging from needle chlorosis and twisting to complete destruction of seed crops. The genus has been subject to taxonomic revision, with 22 species recognized from North America alone.
Walshomyia
Walshomyia is a genus of gall midges (family Cecidomyiidae) established by Felt in 1908. The genus comprises four described species, all of which induce galls on coniferous host plants. Members of this genus are associated with Cupressaceae, including junipers and cypresses. The genus is well-represented in citizen science observations, with over 3,000 records documented.