Foraminifera taxon details
From editor or global species database
Diagnosis Test elongate, arcuate, circular to ovoid in section, proloculus ovoid, commonly with basal spine, later chambers uniserial, asymmetrical, and inflated on the convex margin of the test, sutures straight, flush and obscure in the early stage, final one or two slightly constricted; wall calcareous, fibrous, radiate, perforate, secondarily mesolamellar, with lamellae from each newly added chamber covering at least one previous chamber but not completely covering the test at each instar, surface with ten to twenty-five longitudinal costae that may be discontinuous and may bifurcate or die out distally, running from the convex margin obliquely across the test toward the apertural region on the concave margin, costae appearing in thin section as imperforate microgranular wedges in the radially built wall; aperture terminal, eccentric, produced on a short neck at the straight to concave margin of the test, round, bordered by radial ribs. L. Jurassic; cosmopolitan. (Loeblich & Tappan, 1987, Foraminiferal Genera and Their Classification) [details]
Diagnosis Test elongate, flattened, bilaterally symmetrical, chambers uniserial and rectilinear, chevron shaped, arched centrally, but later chambers with a downward projecting median lobe on each of the flat sides; wall calcareous, ultrastructure unknown, surface with longitudinal costae; aperture terminal, oval and slitlike. L. Jurassic (M. Lias); USSR: Northwest Siberia. (Loeblich & Tappan, 1987, Foraminiferal Genera and Their Classification) [details]
From editor or global species database
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