Here's a small sample from the French version of the Quebec guide that illustrates some of the features and how to interpret them. In the English version of the guide, the order of the names is inverted, and the English versions of the size and status codes are used.
Markings on both upper and lower wing surfaces ( shown on the left and right respectively for this sample panel ) can be helpful for identification. In most cases, the view that is most useful for identifying a species is placed on the far left of the panel in question. Note that some butterflies almost never show their upper wing surfaces. In these cases, only the ventral (lower side) view is provided.
The green text specifies one of 5 size codes ( English version codes are shown below in square brackets ):
TP - très petit [ VS - Very Small ]
P - petit [ S - Small ]
M - moyen [ M - Medium ]
G - grand [ L - Large ]
TG - très grand [ VL - Very Large ]
The corresponding size ranges are provided in the legend ( printed on the back panel of the guide ). These indicators are based on measurements of typical specimens, but please note that some species can vary considerably in size from one individual to another.
The red text indicates the species status. ( English version codes are shown below in square brackets ) :
C - commun [ C - Common ]
P - peu commun [ U - Uncommon ]
R - rare [ R - Rare ]
L - localisé [ L - Local ]
M - migrant [ M - Migrant ]
N,S,E,O [ N,S,E,W ]
These codes are explained below:
commun/Common - Relatively easy to find in suitable habitat during the flight season indicated
peu commun/Uncommon - Somewhat harder to find, even during the peak of its flight season
rare/Rare - Seldom seen, even in ideal habitat during the peak of its flight season
localisé/Local - the species in question is usually confined to some kind of specialized habitat (eg. bogs), or seldom strays far from its larval foodplant. You may never see it unless you visit the right habitat.
migrant/Migrant - the species in question does not normally overwinter in the province, but flies North from the U.S. Some species are regular migrants ( eg. The Monarch ), while others are only reported occasionally ( eg. Little Yellow ). Even regular migrants can vary in abundance from year to year.
N,S,E,O/N,S,E,W - the species in question is more commonly found in the corresponding part of the Region. Note that some species designated with " N " may be found at higher elevations in more southerly locations.
Note that these status codes are intended as rough guides. Certain rare species can appear to be relatively common during a good year if you happen to find yourself in just the right habitat during the peak of their flight season. On the other hand, species that are normally common might be tough to locate during a bad year. The codes are intended to reflect average abundance.
Please note that some species have several common names, and Scientific names can change as taxonomists revise species classifications. The names used in the guide have been chosen to align with provincial checklists ( see references ). Each language version contains the common names in both English in French, so regardless of whether you purchase the French or English version, you will have the Common names in both languages. Only the order of the names is changed.
For some species, there is little difference in the appearance between males and females. In other species, sexual dimorphism can be significant. Where there is a noticeable difference, images of both sexes are provided ( as indicated by the symbols ♂ for male and ♀ for female ).
In addition, there are a few species that have seasonal forms or regional variants. Separate images are provided where appropriate.
These charts give a rough indication of the time of year during which you can expect to find each species. Green indicates the period during which they have been most frequently reported ( according to the Ontario Butterfly Atlas Online ). Yellow indicates the period during which there have been fewer reports. Note that some species have very brief flight periods, which can last only a week or two. The timing of this peak flight period can vary from year to year ( depending on weather conditions ), and from place to place ( typically earlier in more Southerly locations ). The result is that when combining reports of sightings over many years and across the province, the peak flight period of such a species may appear much longer than it will ever be in any particular place and in any particular season.