Sanniopileus stultus, Dumitrica & Zügel, 2003

Dumitrica, Paulian & Zügel, Peter, 2003, Lower Tithonian mono- and dicyrtid Nassellaria (Radiolaria) from the Solnhofen area (southern Germany), Geodiversitas 25 (1), pp. 5-72 : 44-46

Sanniopileus stultus n. sp. ( Fig. 23 A-D, J)

HOLOTYPE. — Photo No. 42183, 42184; stub Mue 22/10; Musée de Géologie , Lausanne, No. 74400 ( Fig. 23A, B ). ETYMOLOGY. — From the Latin stultus : foolish, mad.

MATERIAL EXAMINED. — 15 illustrated specimens and many others not illustrated from the type horizon (sample Mue 22).

DIMENSIONS ( IN µM). — Total length 165-270 (av. 195), length of cephalothorax 125-140 (av. 130), of cephalis 30-45 (av. 35), of thorax 85-100 (av. 90), of apical horn 35-55 (av. 40), of ventral and secondary lateral spines 35-75 (av. 45), of primary lateral spines 90-195 (av. 125), total width 170-180 (av. 175), width of cephalis 43-52 (av. 48), of thorax 80-95 (av. 85).

DESCRIPTION

Cephalis hemispherical, well rounded, with small pores irregularly distributed. All spines threebladed. Apical horn subaxial, straight but slightly curved at the base. Base of horn V a little above bases of horns lr and ll. Ventral and secondary lateral horns strongly curved at the base to achieve a subhorizontal direction, forming right angles with the axis of test. Collar boundary marked by the arches Ll forming a small ridge on the surface of test. Ridge runs below the arches VL to connect, on the ventral part, the bases of horns Lr and Ll. Thorax short, conical with irregular circumferential ridges. Most ridges not continuous, either fading out or being attached to the previous ridge. Several ridges on the proximal part of the thorax slightly garland-shaped, fixed between the insertions of the primary lateral spines. On the inner side of thorax only very few ridges are visible. Circumferential band between ridges concave in outline, usually with one, rarely two circumferential bars parallel with ridges. These bars and ridges interconnected by a system of bars in a zigzag pattern forming triangularlyframed pores. Usually these zigzagged bars arranged to form a system of rosettes centred on the circumferential bars. This regular pattern commonly disturbed in the zones where the ridges disappear. Spines Lr and Ll protruding the test wall at the collar boundary. They are threebladed with an inner blade directed towards the centre of test, and two outer blades. Proximal parts of these spines connected to the test wall through the inner blade, distal parts free, slowly tapering. Spines Lr and Ll of variable length, either ending above the thoracic aperture or reaching far beyond it. Distal part of thorax wide open.

REMARKS

By its morphology this species differs significantly from all the Foremanellinidae so far described.

Figures

FIG. 23. — A-D, J, Sanniopileus stultus n. gen., n. sp.; A, B, holotype, right lateral and apical views showing the absence of dorsal spine; C, D, J, paratypes; C, D, ventral and left lateral views; J, basal view of initial spicule showing the absence of dorsal spine; E-I, Sanniopileus stultisissimus n. gen., n. sp.; E, F, holotype, left lateral and basal views; G-I, paratypes; G, I, left lateral and basal views with details of the initial spicule; H, ventral view. Scale bars: A-H, 30 µm; I, J, 10 µm.