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Dendrospyris binapertonis
Goll , 1968
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Description - Add description
DENDROSPYRIS BINAPERTONIS n. sp. Goll 1968 p. 1420; pl. 173, fig. 5, 6, 10, 11
Sagittal ring subcircular; 54 to 70μ high; 28 to 48μ thick; joined directly to front, apex, and back of lattice shell. Apical and vertical spines short; no frontal or axial spines. Some specimens have no sternal bar; in other skeletons, all eight basal-connector bars joined to basal ring. Basal ring oval, having lateral and sagittal indentations ; 33 to 64μ wide; 27 to 37μ thick; encloses six basal pores. Three or four basal spines circular in cross section; 12 to 55μ long; project from basal ring; taper to simple point or have irregularly branched ends. Basal spine adjacent to each of frontal and primary-lateral bars; some specimens have basal spine adjacent to sternal bar. In some forms, short auxiliary spines project laterally from proximal ends of basal spines adjacent to primary-lateral bars. Lattice shell 75 to 100μ wide; not extending below basal ring; slightly constricted sagittally; has appearance of smooth, thin sheet perforated by subcircular, widely spaced lattice pores 4 to 28μ in diameter. Variable number of lattice bars joined to sagittal or basal rings. Sternal pore present; frontal and vertical pores absent.
Diagnosis:
A species of Dendrospyris characterized by six basal pores, sternal pore, and a lattice shell that is joined directly to the front, apex, and back of the sagittal ring and does not extend below the basal ring.
Etymology:
The trivial name is derived from the Latin words bis, meaning two, and apertonis, meaning opening.
Remarks:
Representatives of Dendrospyris binapertonis n. sp. differ from those of D. damaecornis (Haeckel) and Tholospyris scaphipes (Haeckel) in having a sternal pore, and from those of D. pododendros (Carnevale) in having no frontal pore. Specimens of the type-species of Dendrospyris, D. stylophora (Ehrenberg), have tubercles and long apical spine. Some specimens of D. stylophora have a frontal pore.
Occurrence:
Dendrospyris binapertonis is represented in 13 of the 17 samples between MSN 132P, 90-92 cm. (middle Miocene) and AMPH 9P, 364-366 cm. (late Pliocene).
Holotype: USNM 650357, from core sample MSN 143P, 890-892 cm. (middle Pliocene).
Picture:
5,6,10,11—Dendrospyris bmapertonis Goll, n. sp. Back, left-side, basal, and front views, respectively, of holotype. USNM 650357; core sample MSN 143P, 890-892 cm. X300 | | Goll 1968 |
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