T. carinatus group

Description

Species with c-axis parallel to length of nannolith. These species always show high birefringence, and length-fast orientation.

Typical specimens	morphology	range
	T. carinatus - elongate, parallel sided	NP24-NN2
	T. challengeri - shorter with ridges on two of the blades	NN1-2
	T. milowii - shorter, lozenge shaped	NN1-6