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Identifying genera of the subfamily Aleocharinae is distinctly challenging. This is primarily a result of the small size of most taxa (the average size is about 3 mm) and the consequently minute size of many distinctive features, coupled with the vast array of valid taxa, many of which are superficially similar. However, except possibly for some poorly characterized genera in the tribe Athetini, it should be possible to identify most genera in the North American fauna, and many are quite distinctive. Since one cannot make aleocharines larger, consistent aleocharine identification requires: good optical equipment that is appropriate for the size of aleocharine specimens, well-prepared specimens, and patience and dedication. It is especially important to have well-prepared specimens; specimens which are contorted, dirty or embedded in large quantities of mounting medium so that the legs and ventral surface of the body are obscured usually cannot be identified until they are relaxed and remounted.

Correct counting of tarsal segmentation is central to identification using this key. This can be difficult for small to minute aleocharines. Some hints may be helpful. View the tarsi under high magnification (70-100 times magnification or more) against a bright background (back-lighted); this frequently makes the divisions between the segments more apparent. Remove a leg, place it on a microscope slide as a dry mount, and view it with transmitted light using compound optics; you can glue the leg back onto the point with the specimen after you are finished. Make a temporary or permanent microscope mount for transmitted light viewing.

In general, identification is greatly facilitated if one first mounts one or two cleared and dissected specimens of a series on microscope slides, either as temporary mounts in glycerine or in Hoyer's medium, or as permanent slides in balsum, euparal or another permanent medium. This is time consuming, but it makes it possible to reliably count tarsal segmentation and to clearly examine a number of minute, but distinctive, characteristics, especially in the mouthparts. Many of these same features can be seen with considerable effort and high magnification on well-prepared dried and pointed specimens, but they are near the lower limit of dissecting optical resolution and mistakes in interpretation are likely. Cleared and dissected specimens mounted on microscope slides, and examined using high quality compound optics, are essential for serious taxonomic and phylogenetic study of aleocharines.

It is frequently necessary to adjust or move body parts, antennae or legs in order to examine important key characteristics. Moore, Hlavac and Frommer (1976) describe a method of rapidly relaxing dried and pinned specimens using Barber's solution. We have found this method to be very effective and useful for adjusting body parts of pointed and dried aleocharine specimens for identification and detailed examination.