Identification of T. oleracea larvae and adults (Cont.)

A different physical character for separating T. oleracea and T. paludosa larvae has been described by George Byers, based on differences he observed in the pattern of microscopic hairs (setae) on identified larval specimens from Russia (G. Byers, personal communication and (Savchenko, 1961)). Unfortunately, attempts to apply the methodology to identify larvae collected in this survey were also inconclusive, suggesting possible variation of larval morphology (from geographically distant populations) and/or clarification of the character and refinement of the identification technique is needed.

In contrast, identification of adult T. oleracea and T. paludosa, which also are very similar overall, was simple and unambiguous due to clear physical characters. A very clear character for distinguishing the two species is the separation of the compound eyes on the ventral surface (underside) of the head (From Brodo, 1994), as shown in the following figures.

A different character to separate the species, which applies only to females, is length of wings. Female T. oleracea wings are clearly longer than the abdomen as shown in figure 7, whereas wings of female T. paludosa are shorter than the abdomen.

A more complete description of adults of both exotic species and comparison pictures of similar native crane fly species have been compiled as an internet web page and is accessible via the WSDA web site at: http://www.wa.gov/agr/index.htm. Internet website posting of identification information is expected to offer several dynamic advantages over print publication, thus only the key identifying characters are presented here. Information and graphics in digital format may be freely copied directly from the web page and updates and new identification resources may be added to the web site as they are developed.