Life-history of the leaf-eating crane-fly Cylindrotoma splendens , Doane (Diptera, Tipulidae)

Abstract

On April 28, 1917, whilst on a journey undertaken with a view to determining the distribution of the Pear Thrips, Taeniothrips inconsequens Uzel on Vancouver Island, the author had the good fortune to discover a curious, Tipulid larva quite unknown to him. The locality of the discovery was in the rural district of Westholme about 40 miles north of the town of Victoria. His attention was first drawn to the insect by his co-worker, Mr. E. W. White, Assistant Horticulturist of the Department of Agriculture, British Columbia, whose interest was first aroused by the feeding activities of the larva. In a rich woodland timbered by lofty cedars and spreading, largeleaved maples, there was growing in great luxuriance the false bugbane, Trautvetteria grandis , which affects damp and wellshaded habitats. It was on the leaves of this perennial, ranunculaceous herb that the larvae in question were feeding in large numbers, eating out large, irregular holes. The insect was successfully reared, and the adults submitted to Mr. Chas. P. Alexander, Department of Entomology, Cornell University, who identified the species as Cylindrotoma splendens , Doane, in a letter dated May 25, 1917. In reply to a letter of the author, in which the finding of the larvae was mentioned and their general appearance outlined, Mr. J. R. Malloch, of the Illinois State Laboratory of Natural History, Urbana, Illinois, under date of May 20, 1917, suggested with admirable foresight, that the species perhaps belonged to the tribe Cylindrotomini of the Tipulidae; but, as material had not then been forwarded to him, he could not naturally diagnose the species from a brief, written description. Later, however, he was able to corroborate Mr. Alexander’s determination from specimens sent from the writer’s collection.