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Botryostrobus? parsonsae Hollis, 1997

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Description: Narrowly conical test of five medially-inflated segments, very rarely six segments. Ovate cephalis with very small apical horn and lateral directed vertical tube; external expression of vertical tube is usually a large pore on the side of the cephalis, but in well-preserved specimens a tubular structure extends down from the area of the pore to the third or fourth segment, following the contour of the test. Surface of the cephalis otherwise imperforate or dimpled. Thorax hemispherical, imperforate or sparsely perforate; surface simply dimpled or with four rows of occluded pores, quincuncially arranged in regular hexagonal frames. Single row of open pores at collar and lumbar strictures. Abdomen and subsequent segment medially inflated, separated by rounded constrictions, and increase regularly in size. Pores on these segments usually occluded, occasional patches of small, circular, open pores; quincuncially arranged in 4-8 rows, set in regular hexagonal frames; 7-10 rows on final segment. Constrictions between post thoracic segments have 2-3 transverse rows of open, unframed pores. Final segment terminates with 1-2 rows of open pores, framed or unframed, above slightly constricted thickened peristome.
Remarks: This species is doubtfully included in Botryostrous because it differs from all other members of the genus by having a relatively small cephalis, several rows of pores in constrictions between segments, and no segment in which all pores, occluded and open, are in well-defined transverse rows.
Hollis 1997











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