Sphaerophthalmus sp. B

Ahlberg, Per, Szaniawski, Hubert, Clarkson, Euan N. K. & Bengtson, Stefan, 2005, Phosphatised olenid trilobites and associated fauna from the Upper Cambrian of Västergötland, Sweden, Acta Palaeontologica Polonica 50 (3), pp. 429-440 : 434

Sphaerophthalmus sp. B

Fig. 3B .

Material.—A damaged right librigena (width excluding spine about 0.5 mm) lacking the anterior part.

Remarks.—This specimen is in many ways comparable to the librigenae of Sphaerophthalmus cf. alatus ( Fig. 2L, M ) in terms of the genal spine set opposite the eye and in the course of the posterior branch of the facial suture. The eye, however, is relatively larger, not so elongated, and has about 80 lenses. The librigena may represent a more adult individual than the librigenae described above as S. cf. alatus .

Figures

Fig. 3. A. Sphaerophthalmus sp. A, cranidium, SMNH Ar59729 (2.21), sample 2. B. Sphaerophthalmus sp. B, right librigena with intact eye, SMNH Ar59730 (3.11), sample 2. C. Sphaerophthalmus sp. C, incomplete thoracic tergite, SMNH Ar59731 (2.19), sample 2. D–F. Peltura cf. transiens (Brögger, 1882). D. Pygidium, SMNH Ar59732 (1.3), sample 1. E. Pygidium, SMNH Ar59733 (2.7), sample 2. F. Small pygidium, SMNH Ar59734 (3.12), sample 2. G. Peltura cf. paradoxa (Moberg and Möller, 1898), pygidium, SMNH Ar59735 (1.7), sample 1. H, I. Peltura sp. A. H. Pygidium, SMNH Ar59736 (1.2), sample 1. I. Transitory pygidium, SMNH Ar59737 (1.21), sample 1. J. Peltura sp. B, transitory pygidium, SMNH Ar59738 (1.6), sample 1. K–P. Indeterminate olenid fragments. K–M. Occipital rings. K. SMNH Ar59739 (1.19), sample 1. L. SMNH Ar59740 (1.15), sample 1. M. SMNH Ar59741 (2.14), sample 2. N. Axial ring seen edge on, SMNH Ar59742 (1.18), sample 1. O. Axial ring, SMNH Ar59743 (2.22), sample 2. P. Incomplete thoracic tergite, SMNH Ar59744 (1.24), sample 1. Scale bars 0.1 mm.

Fig. 2. A. Parabolina sp., juvenile pygidium, SMNH Ar59711 (3.13), sample 2. B–H. Ctenopyge sp. B. Fragmentary cranidium, SMNH Ar59712 (2.8), sample 2. C. Left librigena with intact eye, SMNH Ar59713 (1.12), sample 1. D. Left librigena with intact eye, SMNH Ar59714 (1.13), sample 1. E. Small pygidium, SMNH Ar59715 (1.23), sample 1. F. Pygidium, SMNH Ar59716 (2.6), sample 2. G. Pygidium, SMNH A59717 (2.2), sample 2. H. Pygidium, SMNH Ar59718 (1.4), sample 1. I–K. Sphaerophthalmus humilis (Phillips, 1848). I. Cranidium, SMNH Ar59719 (2.20), sample 2. J. Pygidium, SMNH 59720 (1.5), sample 1. K. Pygidium, SMNH Ar59721(2.5), sample 2. L, M. Sphaerophthalmus cf. alatus (Boeck, 1838). L. Right librigena with intact eye, SMNH Ar59722 (1.20), sample 1. M. Left librigena, SMNH Ar59723 (1.14), sample 1. N, O. Sphaerophthalmus cf. majusculus Linnarsson, 1880. N. Pygidium, SMNH Ar59724 (1.15), sample 2. O. Pygidium, SMNH Ar59725 (2.1), sample 2. P. Sphaerophthalmus sp. A?, juvenile cranidium, SMNH Ar59726 (2.11), sample 2. Q–R. Sphaerophthalmus sp. A, sample 1. Q. Cranidium, SMNH Ar59727 (1.8). R. Cranidium, SMNH Ar59728 (1.10). Scale bars 0.1 mm.