Minylitha convallis Bukry, 1973
A kite shape nannolith in plan view whereas dog-bone shape at the side view. Having central depressions on both sides. The plan view is non-birefringent [arguable weekly birefringent] but strongly birefringent on its side view.
Minylitha convallis is distinguished from Minylitha cancellata Browning & Bergen in Browning et al., (2017) by lacking longitudinal and traverse ridges.
Browning, E., Bergen, J. A., Blair, S. A., Boesiger, T. M. & de Kaenel, E., (2017): Late Miocene to Late Pliocene taxonomy and stratigraphy of the genus Discoaster in the circum North Atlantic Basin: Gulf of Mexico and ODP Leg 154.- Journal of Nannoplankton Research. 37(2-3): 189-214.
Bukry, D., (1973): Coccolith stratigraphy, eastern equatorial Pacific, Leg 16, Deep Sea Drilling Project. - Initial Reports of the Deep Sea Drilling Project. 16: 653-711.
DSDP Leg 3, Site 15, Mid-Atlantic Ridge, Atlantic Ocean