''Triglyphus primus'' is a species of hoverfly, from the family Syrphidae, in the order

Diptera Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced ...

. The larvae seem to be host-specific to an aphid species ''

Cryptosiphum ''Cryptosiphum'' is a genus of true bugs belonging to the family Aphididae The Aphididae are a very large insect family in the aphid superfamily ( Aphidoidea), of the order Hemiptera. These insects suck the sap from plant leaves. Several thous ...

artemisiae'' which creates

gall Galls (from the Latin , 'oak-apple') or ''cecidia'' (from the Greek , anything gushing out) are a kind of swelling growth on the external tissues of plants, fungi, or animals. Plant galls are abnormal outgrowths of plant tissues, similar to be ...

s on Mugwort ''

Artemisia vulgaris ''Artemisia vulgaris'', the common mugwort, is a species of flowering plant in the daisy family Asteraceae. It is one of several species in the genus ''Artemisia'' commonly known as mugwort, although ''Artemisia vulgaris'' is the species most ...

''.

References

Diptera of Europe Pipizinae Insects described in 1840 Taxa named by Hermann Loew {{Syrphidae-stub