Phytomyza conyzae [Diptera: Agromyzidae] in Leaf and stem mines of British flies and other insects

The leaf and stem mines of British flies and other insects

(Coleoptera, Diptera, Hymenoptera and Lepidoptera)

by Brian Pitkin, Willem Ellis, Colin Plant and Rob Edmunds

Phytomyza continua Hendel, 1920
[Diptera: Agromyzidae]

Phytomyza continua Hendel, 1920. Arch. Naturgesch. 84A(7) (1918): 158
Phytomyza cardui Hering, 1943. EOS 19: 55. [Synonymised by Spencer, 1976: 405]
Phytomyza polyarthrocera Frey, 1946. Notul. ent. 26: 54. [Synonymised by Spencer, 1976: 405]
Phytomyza zetterstedti Rydén, 1951b. Ent. Tijdschr. 72(1-2): 179. [Preoccupied]
Phytomyza zetterstedtiana Rydén, 1953. Ent. Meddr. 26: 16. [Synonymised by Spencer, 1976: 405]
Phytomyza continua Hendel, 1920; Spencer, 1972b. Handbk ident. Br. Ins. 10(5g): 82, 83 (fig. 268)
Phytomyza continua Hendel, 1920; Spencer, 1976. Fauna ent. Scand. 5(1): 405-6, figs 708-710.
Phytomyza continua Hendel, 1920; Spencer, 1990. Host specialization in the World Agromyzidae (Diptera) : 251, 255, 256 (fig. 959-60).

Leaf-miner: Larva feeds along the mid-rib, predominantly on the lower surface and there is little evidence of gall-like swelling. Pupation takes place at the base of the midrib (Spencer, 1976: 496).

In Burdock the species bores in the petioles, and in Chicory it is a root borer, but in thistles it mainly lives in the base of the midrib, making from there brief excursions into the blade. The midrib somwhat swells, gall-like and obtains a somewhat darker shade. Pupation takes place within the mine (Bladmineerders van Europa).

Larva: The larvae of flies are leg-less maggots without a head capsule (see examples). They never have thoracic or abdominal legs. They do not have chewing mouthparts, although they do have a characteristic cephalo-pharyngeal skeleton (see examples), usually visible internally through the body wall.

The larva is described by Dempewolf (2001: 183).

Puparium: The puparia of flies are formed within the hardened last larval skin or puparium and as a result sheaths enclosing head appendages, wings and legs are not visible externally (see examples).

Whitish; posterior spiracles on an angular projection, each with some 18 bulbs (Spencer, 1976: 496).

Hosts in Great Britain and Ireland:

Apiaceae
Carduus				Robbins, 1991: 121
Carduus				Spencer, 1990:
Centaurea				Pitkin & Plant

Hosts elsewhere:

Apiaceae
Arctium			Bladmineerders van Europa
Arctium	minus	Lesser Burdock	Dempewolf, 2001: 183
Carduus			Spencer, 1976: 405
Carduus			Spencer, 1990: 251
Carduus	crispus	Welted Thistle	Bladmineerders van Europa
Cichorium			Bladmineerders van Europa
Cirsium			Spencer, 1976: 405
Cirsium			Bladmineerders van Europa

Time of year - mines: March (Hering, 1957).

Time of year - adults: May-July, September-November.

Distribution in Great Britain: Britain including Breconshire, Cambridgeshire, East Norfolk, Monmouthshire, North Somerset, Oxfordshire and South-west Yorkshire (NBN Atlas).

Distribution elsewhere: Widespread in continental Europe including Austria, Denmark, Finland, France, Germany, Sweden (Spencer, 1976: 405), Belgium, Czech Republic, Latvia, Lithuania, Poland, Spanish mainland and Switzerland (Fauna Europaea).

NBN Atlas links to known host species:

Arctium minus, Carduus crispus

British and Irish Parasitoids in Britain and elsewhere:

Ichneumonoidea - Links to species no longer available
Chorebus leptogaster (Haliday, 1839)	Braconidae: Alysiinae


External links:	Search the internet:
Biodiversity Heritage Library Bladmineerders van Europa British leafminers Encyclopedia of Life Fauna Europaea NBN Atlas NHM UK Checklist	Find using Google Find using Google Scholar Find images using Google


	Last updated 10-Jul-2019 Brian Pitkin