Published online by Cambridge University Press: 01 May 2009
HEAD-shield acutely triangular. Glabella elongated, subpentagonal, widest across middle, gently convex or subcarinate, without furrows or lobes, having anterior half freely projecting in front of cheeks and produced into a long slender straight horizontal spine grooved along its upper and lower surfaces, fully twice the length of the glabella. Axial furrows nearly straight, diverging anteriorly, with a small deep slit-like pit at their anterior end. Fixed cheeks smooth, broadly triangular, nearly equilateral, reaching half-way up the glabella, with posterior lateral angles slightly curved back. (Free cheeks unknown). Facial sutures slightly sigmoidal. Pleuro-occipital furrow straight, strong, marking off rather broad band-like occipital segment; meso-occipital furrow and segment scarcely defined, smooth, without median tubercle.
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