TECHNIQUES

Mounting Ants
Because ants are too small to pin their bodies directly, they are glued onto the tips of small elongate-triangular or elongate-trapezoidal cards (= points) which are pinned beforehand. Typical way of mounting ants is as in photographs below. Because the center of balance of ants' body is usually located in the posterior part of mesosoma, the ventral faces of middle and hind coxa are glued. The ventrum of petiole which often has diagnostic characteristics should not be covered with glue. The tip of points should not be projected from ants' bodies.

Points
I use relatively elongate-triangular and elongate-trapezoidal points with ca. 10 mm in length and ca. 2.5 mm in basal width. Elongate-trapezoidal points are used for mounting large ants stably. The length of points depends largely on one's preference. Specimens mounted on short points (ca. 6–7 mm in length) can be operated easily in the working field of microscopes. I, however, prefer long points, because I insert a piece of gray paper between the ant body and the pin in order to hide the pin when photographying specimens. Anyways, specimens mounted on points should not be projected beyond the left margin of the label(s). This means that the maximal length of point may be ca. 12 mm. I use light-gray card paper for producing points.

Hide Wood Glue
White bond (polyvinyl acetate emulsion adhesives) is commonly used by Japanese entomologists to bond specimens on the points. Although I have used it for a long time it, my frined, Dr. Maruyama, recommended me to use hide glue. Histrical wood clafts in museums and galleries ensure the endurance of hide wood glue over hundreds years. Hide glue is easily solved within warm water, this feature allow us to remove specimens from points and re-mount them again with different angles/positions. Pure hide glue is saled as solid material. In order to make it liquid it should be put into small pot with a certain amout of water and heated at 60–70˚C. It is inconvenient, so I use "Titebond — liquid hide wood glue". The adhesive is not a pure hide glue, and so I do not know the endurance of the adhesive being over hundreds years. It, however has the following features superior to polyvinyl acetate emulsion adhesives: 1) the concentration can be easily adjusted by adding water or exposing it to the air; 2) the adhesive is slowly fixed (his feature is convenient espesially in mounting tiny specimens with a little amount of the adhesive); 3) specimens are tightly fixed with a small amount of the adhesive. It is too much sticky in some situations, but it may not be a serious problem. If the adhesive becomes gelling in the low room-temperature during winter, it should be placed on a disposable pocket warmer.

Printer and Paper for Producing Data Labels
Dr. Stefan Cover, an acting curator at "Ant Room" of the Museum of Comparative Zoology, produce a lot of data labels (ca. 10 mm x 15 mm) by very fine and beautiful hand-writing, but unfortunately I do not have such skill and patience. Instead I prepare by using a word processor software (Adobe InDesign) A4-sized formats on which ca. 370 pieces of labels for dry-mounted specimens (13 lines x 29 rows) or ca. 90 pieces of labels for wet specimens (6 lines x 15 rows) are arranged. The formats for dry-mounted specimens are printed on card papers (see the photo below) and those for wet specimens on copy papers by using an Epson PX-930 pigment-ink-jet printer. Pigment ink has resistance to water and Ethanol, and so it is suitable for printing labels. Photo papers of which the surfaces are put the chemical undercoating on should not be used, because the undercoating may be deteriorated under the long-term exposure in air containing naphthalene, etc. Laser printer should not be used for printing labels for wet specimens, because toner-ink peels off from the surface of paper in a preservation in Ethanol for some years. This is a strong recommendation based on my experiences.

SPECIMEN IMAGING

Backgrounds
Most of ant taxa were described by Westerners in the late 19th and the early 20th centuries. Descriptions of new taxa at that time were usually short and inadequate, and were only rarely accompanied with drawings. Since the beginning of the late 20th century, taxonomic revisions of ants based on modern principles and methodology have appeared. These principles often included precise drawings. Since Taylor and Beaton (1970) many myrmecologists have published scientific papers and books involving SEM images (e.g., Taylor, 1973; Bolton, 1994). SEM is really a powerful tool not only for examining very tiny organs such as sensillae and glands but also for photographing a whole body with an extra-deep focus and to image sculpture on the body surface which is hard to describe or draw. For taxonomists dealing with small to tiny insects these merits are significant enough to ignore demerits such as “complicated preparation of samples”, “loss of color information” and “separation from our vision through optical (stereographic) microscope”. It is almost impossible to take well-focused images of small-sized ants using a digital camera attached to an optical stereographic microscope, without using a photo-montage software mentioned below. The focus range of optical microscopes becomes shallower under higher magnification. Thus, when the sculpture on the frons is focused, the outline of the head might be less focused. Reversely, when the outline of the head is focused, the sculpture on the frons might be less focused. Images given in “Ants of Japan” (Japanese Ant Datanase Group, 2003) shows the best quality using such a stereographic microscopic system.

Multifocus-imaging
Very recently, however, photo-montage software released from several companies and individuals brought a new hope to digital imaging using optical microscopes. Multi-focused images of dry-mounted specimens in this website were produced using Helicon Focus 4.03 Pro (MP). The software constructs a single multi-focused images from a series of source images taken by a certain focal interval from the lowest to highest focal planes. Although the automatical construction is surely excellent, careful improvement usign the retouching function may be needed in some cases (especially the cases when imaging small-sized and low-contrast objects). When fine hairs and other parts which were not recognized automatically were found, the focused parts from the source images were copied to the montage image using retouching function. Artifacts (ghost images) and unnecessary parts (unfocused appendages, insect pin, etc.) surrounding or covering terget objects were erased and cleaned up using the retouching function of Helicon Focus. Finally, the background were cleaned up, and the color balance, contrast and sharpness were adjusted using Adobe Photoshop CS2. I would like to wish thank Dr. Gary D. Alpert (Harvard Univ., USA) who introduced me to a digital imaging technique using Auto-Montage software (now I use Helicon Focus).

Optics
Source images were taken by a Nikon Coolpix 8400 digital camera attached to a Nikon AZ100 zoom microscope. The optics with a mono-axial vertical beam path is indispensable for obtaining clear source images with high resolution. I usually use 1x and 4x Plan Apo objective lenses of AZ100, but often mount 4x, 10x and 20x objective lenses of Nikon light microscope on AZ100 using a hand-made adaptor. When those light microscope lenses are mounted on AZ100, the magnification is reduced approximately 50% (i.e., 4x objective lens provides 2x magnification when mounted on AZ100).

Illumination
Illumination is also very important for obtaining clear source images. I am now used an illuminator with a 28W cirular fluorescent tube. My friend, Mr. Ohnishi (Kagoshima, Japan), kindly provided me the illuminator which is only for exhibition in shops but not for sale. I remodeled it in order to mount my AZ100.

Contrivances
When photographing an ant specimen with smooth body, its strong reflection can be reduced by covering it with semitransparent paper. When photographing the lateral view of an ant, a stainless-steel (silver-colored) pin may lie behind the body and may cause diffused reflection which much reduces the quality of the source images. I adopt a simple and easy way. I just insert a piece of gray paper between the body and the pin and hide the pin. The point on which the ant is mounted is hold in a slit of the piece of paper.

Furthermore, I cut points out of a thick paper colored in gray using a pigment marker (uni POSCA PC-8K). Cut ends should be colored after the points are pinned. I show below a montage image of Paratopula worker mounted on a gray-colored point with a gray-colored background (before making an improvement using Photoshop). It seems to be... excellent! Isn't it?