Acrididae - Specimen Preparation
Most grasshopper species are large enough to be pinned (versus pointed). Depending on the size of the specimen a # 1, 2, or 3 sized insect pin can be used. The pin should be inserted near the posterior portion of the pronotum, just to the right of the midline, and exit through the right side of the first sternite. Enough room should be left at the top of the pin as to allow the specimen to be picked up by the pin without the insect being touched. The pin should be oriented as strait as possible vertically. A pinning block may be used to assure uniformity of the height of the specimen and associated labels.
In most museums, space is a primary limiting factor on the number of specimens a collection can hold. To minimize the amount of space taken up by an individual specimen, it is best if extremities (legs, antennae, and wings) are tucked in close to the body, unless there are diagnostic characters on them that necessitate them being pulled out (see comments on the Oedipodinae below) . Tucking the extremities in also lessens the likelihood that they will be broken off.
For most Orthoptera it is best if the antennae are tucked downward in front of the face and may run underneath the body in some species with long antennae. Wings are not spread in most of the Orthoptera, the only exception being the band-winged grasshoppers belonging to the subfamily Oedipodinae. For these the use of a spreading board will be needed. The front margin of the hind wing should be perpendicular to the body with hind margin of the forewing placed just in front, but not touching it. The legs should be tucked in tight against the body with the femurs of the forelegs facing anteriorly. Again the Oedipodinae, require some special treatment as there are diagnostic characters on the inner face of the hind femora of most species.
In some cases, identifications cannot be made without viewing the internal genetalia structures of the male. This requires prying the subgenital and supra-anal plates apart, then using forceps or pin with curved point, to pull the scleratized structures out just enough to be viewed. It is best if this is done before the specimen is completely dry.
Labels: Associated collection information is of the utmost importance when collecting specimens for scientific study. Collection information typically consists of collection locality (State, county/parish, latitude and longitude/ township, range, and section), date of collection, name of the collector (often first and second initial followed by the fully spelled our last name), and any pertinent habitat or behavior information, which usually goes on the second label. Sometimes a third label that gives the scientific name, author of the name, initials and last name of the identifier, and year it was identified is placed on the pin. This type of label is referred to as a determination label. It is good idea to place these on all the specimens that have been identified, as that it may aid future researchers to know what specimens have been looked at by experts and which ones have not.
Example first label
MISS., Oktibbeha Co.
Osborn
33°36'53"N88°43'52"W
12 July 2006
J. G. Hill
Example second label
Collected in
Black Belt
Prairie remnant
Example third or determination label
Arphia sulphurea
(Fabricius)
Det. J. G. Hill 2006
