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Dorcadospyris confluens (Ehrenberg, 1873)

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DORCADOSPYRIS CONFLUENS (Ehrenberg) PI. 58, figs. 9-12; Text-fig. 2

Description.—Sagittal ring "D-shaped"; 41 to 51µ high; 28 to 39µ thick; joined directly to lattice shell between apical and vertical spines. Two to four pairs of connector bars project from front of sagittal ring; frontal, primary-, and secondary-lateral bars joined to basal ring.
Tertiary-lateral bars attached to lattice shell above basal ring; no sternal bar.
Basal ring subcircular, indented laterally; 34 to 42µ wide; and 23 to 42µ thick; not joined directly to sagittal ring; encloses five basal pores. Lattice shell 53 to 62µ wide; tuberculate;
surrounds the front of sagittal ring. In some specimens, 10 to 13 broad, flat basal spines project from base of lattice shell that extends 8 to 28µ below basal ring. In other specimens, the lattice shell does not extend below basal ring, and basal spines, 10 to 22µ long, project from basal ring. Lattice bars thin, and a variable number of them are joined to sagittal or basal
rings. Lattice pores circular and 2 to 5µ in diameter. Vertical pore present; no frontal or sternal pores.


Remarks.—Representatives of Dorcadospyris confluens differ from those of Dorcadospyris argisca in having no lattice pores that are adjacent to the primary-lateral bars and between the basal ring and basal spines and from those of Dorcadospyris costatescens, n. sp., in having no lattice spines. Unlike specimens of Dendrospyris stabilis Goll, Dendrospyris inferispina Goll, and Dendrospyris pannosa Goll, those of Dorcadospyris confluens have basal spines and no sternal bar. Skeletons of the type-species of Dorcadospyris, D. dentata, have auxiliary spines on the two massive basal spines that project from the basal ring.


Occurrence.—Representatives of Dorcadospyris confluens are in all but one of the samples between Palmer station 4131 (Eocene) and MP 5-1, 30-35 cm. (lower Oligocene), and JYN V 16P, 220-222 cm. (upper Oligocene). Hypotype.—USNM 650350, from Palmer station 4131.

Goll 1969


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