- Dalmanites limulurus
- Middle Silurian Age
- Rochester Shale
- Middleport, New York
- The trilobite measures approx. 2 7/16″ long
Dalmanites is a genus of trilobite in the order Phacopida. The trilobites of this genus have slightly convex exoskeletons with an average length of 4–7 cm (1.5 – 2.75 in). The cephalon is semicircular or parabolic. The glabella (center portion of the head) is often pear-shaped, and tapers outward toward the front. The glabella also always contains three pairs of obvious glabellar furrows. Also prominent are the large mosaic (schizochroal) eyes.
The thorax is composed of eleven segments, with the relatively large pygidium with a slender axis of 11 to 16 rings and 6 or 7 pleural ribs. The pygidium ends in a striking tail spike.
The Dalmanites are typically found when slabs of matrix from the “Dalmanites Layer” are split open. Typically, the eyes remain in one half of the matrix and the rest of the bug remains in the other half. They eyes are prepped out of the matrix and reattached to the bug then the preparation of the bug and matrix (cracks repairs) is completed.