Download high resolution image here.

These images follow earlier egg mass images in a series (linked below) documenting the development of a scale insect infesting the pinyon (Pinus edulis) tree in the southeast corner of the Federal Credit Union parking lot on the Corner of Sherman Ave. and Chanute St. (Albuquerque East 7.5 minute quadrangle), Kirtland AFB, Bernalillo Co. NM.

The dimension cited is the length of the lower of the two on the right with a clear dorsal view. Larvae were actively hatching within the egg masses. They were immobilized by exposure to toluene vapor for about 5 minutes for the 2 hours needed to take the 500 images used to create the subject image. The intent was to kill them for the picture (which requires a static subject), but they mostly recovered.

The second and third images in this linked group are from the same population, but preserved to better image at higher resolution. They are from a sample of the egg mass left for several days in an HDPE (plastic) bottle. During that time, thousands of crawlers distributed themselves uniformly over the inner surface of the bottle, where they eventually died and desiccated. I mounted the two linked specimens on the end of 3 mil tungsten wires coated with euparal mounting adhesive. One was mounted to show the dorsal surface, the other the ventral. The specimens are extremely flat (about 40-50 µm), at least upon desiccation. I was unable to take a good lateral image stack due to narrow focus bands. I had originally intended to stabilize the appearance with HMDS, but upon evaporation, specimens so treated curled laterally into a tube, with the left flank almost bending around to the right flank. The crawlers which died untreated on HDPE, though, remained quite flat, probably due to adhesion of their tarsi to the substrate. During life, at least, adhesion is very good, as evidenced by the fact that they cannot all be rinsed off with a stream of water from a tap; scrubbing is required. The appearance of the desiccated specimens resembles more that of the subsequent quiescent stage linked below than it does the original crawler. They may well have entered the quiescent phase while attached to the HDPE, despite not being on a pinyon needle where this normally occurs.

The fourth and fifth images are of specimens soaked for several days each in 100% ETOH, then in pharmacutical mineral oil to prevent curling. They were then mounted, as before, on 3 mil tungsten wires with euparol to show dorsal and ventral views, respectively. The oil did prevent curling, but the euparol appeared to draw out some oil from the specimens, causing at least the dorsal view specimen to shrivel.

This image is from a CombineZP processed stack of 500 images with a 3.6 µm step taken with a Mitutoyo BD Plan APO 20×/0.42 ∞/0 mm microscope objective + Nikon 135 mm F2.8 AIS telephoto lens + Nikon D300 camera (magnification 13.5×; technique described here).

Phases of development: