Asphondylia

Definition

A large, cosmopolitan genus of gall midges (Diptera: Cecidomyiidae) comprising over 300 described species, all of which induce galls on vascular plants—most characteristically on flowers and flower buds. Species in this genus are among the most diverse and geographically widespread gall-forming cecidomyiids, with substantial undescribed diversity predicted in the Southern Hemisphere. The genus exemplifies the trend toward extreme host-plant specialization common in gall midges, with individual species typically restricted to a single host genus or even species.

Etymology

From Greek 'asphondylos' (meaning 'vertebra' or 'joint'), likely referring to the segmented larval body or the jointed appearance of adult antennal flagellomeres characteristic of cecidomyiids.

Example

Asphondylia verbasci induces flower bud galls on mullein (Verbascum spp.), while Asphondylia opuntiae forms galls on prickly pear cactus (Opuntia) fruits and cladodes; both species demonstrate the genus's tendency toward narrow host specificity despite broad geographic ranges.

Related Terms

• Cecidomyiidae
• Gall midge
• gall
• cecidium
• Loew
• Diptera
• plant-insect interaction
• host specificity

Usage Notes

The genus is treated as feminine in gender (Asphondylia Loew, 1850). When referring to individual species, the full binomial is preferred; 'Asphondylia' alone refers to the genus collectively. Asphondylia is distinguished from other cecidomyiid genera by larval habitat (flower/fruit galls versus leaf or stem galls) and adult morphological characters, though definitive identification often requires associated host-plant data. The genus is frequently cited in studies of gall-induction evolution and plant-insect coevolution due to its species richness and well-documented host associations.