Discoaster? furcatus Deflandre in Deflandre & Fert, 1954
Three-armed stellate calcareous nannofossils exhibit a variety of arm morphologies: The arms can be short, long, parallel-sided, or tapering in shape. The terminations of these arms may have projections (furcations), which can vary in appearance and are often susceptible to dissolution processes. These structural features are essential for characterising and classifying species of Marthasterites.
The optical properties of Marthasterites, including constant extinction (dim) in the plan view and interference colours due to birefringence in the side view under XPL, align with those observed in the family Marthasteritaceae.
Deflandre, G. 1959. Sur les nannofossiles calcaires et leur systématique. Revue de Micropaléontologie 2: 127-152.
Deflandre, G. & Fert, C. 1954. Observations on current and fossil coccolithophorids in ordinary and electron microscopy. Annales de Paléontologie 40: 115-176.