Insect wings possess a number of characters that can help to identify a specimen. One useful character is provided by the presence of structural elements that give rigidity to the airfoil itself; these structural elements are modified tracheae known as “veins”. The total number of veins is an aid in identification. Another useful character is the general overall pattern in which the veins interconnect. The pattern of vein junctions in the wing is usually invariant during development; therefore, this identification program should function correctly for nearly any winged insect in North America, with some exceptions as noted. Generally speaking, the number of veins and their basic sequence of branching are characteristic enough to be able to discriminate insects to the family or subfamily level. The precise measurement of the vein intersections is often useful for species-level identification. However, sometimes unrelated families share the same sequence pattern; conversely, sometimes individual genera within a family may be characterized by different basic sequences.

Currently the effort it takes to identify an insect to the family level depends upon the expertise of the person. Only very broadly trained entomologists can sight-identify most winged insects to family level (flies are especially difficult for most entomologists). The usual practice is to utilize published “dichotomous keys”, which can be a rather lengthy process. Identification to a finer level of resolution (genus- or species-level) is extremely tedious and takes a very extensive library of specialized reference publications. The BugWing© system has been devised to allow the untrained ecologist to identify insects very quickly. It can always be supplemented with conventional techniques (references will be provided where appropriate.)

Caddisfly wing

Damselfly wing

The goal of this project is to be able to identify/distinguish tens of thousands of insects in North America using only the vein junctions of their forewings. We have assembled a broad cross-section of more than 700 images representing the major types of insect wings. The vein junctions of each image are being entered into a database as a reference source. To avoid different interpretations when designating the junctions for various taxa, the junctions will be entered redundantly in the database by several individuals. Once the databasing of the exemplars is complete, an extensive literature research will be done to document the taxonomic limits of each subgroup to the greatest extent possible. We already know that some subgroups will be ‘natural’ (that is, contain only one evolutionary lineage) whereas others will be ‘artificial’ (that is, contain species from more than one unrelated group). 

Within any closely related group of insects, precise quantification of the subunits of the wing veins may be sufficient to identify a specimen to species level. As mentioned above, the developmental pattern of vein junctions is relatively invariant; however there is always individual variation in the distances between wing junctions, as well as variations in the measurements taken. Hence, identification to the species-level of resolution requires a large number of previously-measured reference specimens for each species in the database. As different BugWing@ end-users enter digitized data for additional images of each species, variations in the number and pattern of junctions marked will increase depending upon the skill and knowledge of the users. As data are entered over time, the system “learns” by refining the process for a better fit within the variations.  To obtain such a series for each of the tens of thousands of winged insects in North America will take the cooperation of numerous collaborators. In the meantime, we will develop a proof-of-concept model based on the measurement of a very wide range of types of insects. 

In addition, we have taken more than 500 digital pictures of numerous species within several bee genera (e.g., Melissodes, Bombus) so that we may test the resolution at the genus- and species level. This stage of the identification is stochastic and requires continual refinement of the presentation of new data as the latest results of the multivariate analyses are updated (percent likelihood that the unknown test specimen is species A, B, C …)  For eventual wide adoption by many collaborative end-users, this latter step will require independent testing.

We distinguish between 3 basic types of insect wings:

wings hardened into protective shields. Typical of the Coleoptera (beetles), Orthoptera (grasshoppers, mantids, roaches), Dermoptera (earwigs), and most Hemiptera (true-bugs). These wings cannot be processed in this system since they usually lack definable veins.

Diving beetle Grasshopper

Cockroach Earwig Stinkbug

ACTION: This procedure is NOT applicable for these groups with hardened shield-like wings

wings that are structurally very reduced in very small insects. Typical of the Zoraptera (zorapteran), Thysanoptera (thrips), Homoptera (in part, scales, etc.), and Hymenoptera (in part, parasitic wasps). These groups also cannot be identified with this system since they have so few veins and interlocked cells.

Zorapteran Scale insect

Thrips Fly wing Wasp wing

ACTION: This procedure is NOT applicable for these groups with much reduced wing venation.

Wings that are transparent with apparent ‘veins’ and ‘cells’

Fly wing	Book louse wing
Lanternfly bug wing	Caddisfly wing
Sawfly wing	Butterfly wing

ACTION: Applicable. Click on the menu selection to view PROTOCOLS.