Submitted to: Psyche
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/11/2015
Publication Date: 11/3/2015
Publication URL: http://handle.nal.usda.gov/10113/61822
Citation: Thomas, D.B., Goolsby, J. 2015. Morphology of the pre-imaginal stages of Lasioptera Donacis Coutin(Diptera: Cecidomyiidae), a candidate biocontrol agent of giant arundo cane. Psyche. Available: 10.1155/2015/262678.
Interpretive Summary: Giant arundo cane is a reedy plant that chokes the shores of rivers, streams, and canals, crowding out native riverside vegetation, slowing water flows, and sucking up water at a rate greater than most other plants. It is native to Europe but has invaded the U.S. One reason for its rapid unchecked spread is a lack of natural enemies. In Europe it is attacked by insects that breed in and damage the leaves and roots slowing its growth. One such insect is a tiny fly in the family Cecidomyiidae. The immature stage of the fly is a worm or maggot that lives and feeds inside of the leaves of the arundo cane. The maggot has a hard protuberance on its body that it uses to damage the plant allowing fungi to attack the plant. The maggot then supplements the plant juices with the fungus in its diet. In this article we describe the anatomy of the maggot comparing it to other related species that have a similar ecology in other reedy plants.
Technical Abstract: The larval stages of Lasioptera donacis Coutin consists of three instars, which develop within the mesophyll of the leaf sheaths of Arundo donax (L.) They feed aggregatively on mycelia of an endophytic fungus. The larval instars are similar to other members of the genus except for a three pronged spatula (typically two pronged) and five lateral papillae (typically four). A related species, L. arundinis (Schiner) also has a three-pronged spatula and five lateral papillae but that species has a spinose first instar. The first instar of L. donacis lacks spines. The third instar has a feeding and a non-feeding pre-pupal stage. Papillae associated with the spatula may be sensory organs, campaniform sensillae and sensilla ampulacea, related to extra-oral digestion of the fungal mycelia. Pupation occurs in the host plant within a silken cocoon.