The basement of the Central Pontides, and by implication that of Crimea, consists of pre-Permian low-grade metaclastic rocks intruded by latest Permian – Early Carboniferous (305–290 Ma) granitoids. Further up in the stratigraphic sequence are Triassic limestones, which are now preserved as olistoliths in the deformed Upper Triassic turbidites. New conodont and foraminifera data indicate an Anisian to Carnian (Middle to Late Triassic) age for these hemi-pelagic Hallstatt-type limestones. The siliciclastic turbidites surrounding the Triassic limestone contain the Norian (Late Triassic) bivalve Monotis salinaria; the same species is also found in the Tauric series in Crimea. The Upper Triassic flysch in the Central Pontides is locally underlain by basaltic pillow lavas and includes kilometre-size tectonic slices of serpentinite. Both the flysch and the serpentinite are cut by an undeformed acidic intrusion with an Ar–Ar biotite age of 162 ± 4 Ma (Callovian–Oxfordian). This indicates that the serpentinite was emplaced into the turbidites before Middle Jurassic time, most probably during latest Triassic or Early Jurassic time, and that the deformation of the Triassic sequence pre-dates the Middle Jurassic. Regional geological data from the circum-Black Sea region, including widespread Upper Triassic flysch, Upper Triassic eclogites and blueschists of oceanic crustal affinity, and apparent absence of a ‘Cimmerian continent’ between the Cretaceous and Triassic accretionary complexes indicate that the latest Triassic Cimmeride orogeny was accretionary rather than collisional and is probably related to the collision and accretion of an oceanic plateau to the southern active margin of Laurasia.

Successive evolutionary trends control the genera Paragondolella Mosher and Metapolygnathus Hayashi over the about 20 Ma long Aegean-Tuvalian timespan. In consideration of their evolutionary criteria, these genera have been retained together with Carnepigondolella Kozur and the two new genera proposed herein, Mazzaella (type species M. carnica) and Hayashiella (type species H. nodosa). Mazzaella n. gen. represents a Late Julian side branch of Metapolygnathus, harbouring a platform ornamentation similar to the several million years younger Tuvalian lineage of Carnepigondolella, issued from Hayashiella n. gen. that is intermediary between Metapolygnathus and Carnepigondolella, based on appearance and platform ornamentation.

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Acuminate Middle-Late Triassic Gondolellidae are characterized by an ellipsoid platform with a central to posterior amygdaloid basal cavity and an octomembrate apparatus of gondolelloid affinity. Starting with a neospathodiform proteromorph during the Anisian, their anagenetic lineage developed during the Fassanian, Longobardian, and Julian, ending in another neospathodiform proteromorph. As the increase in complexity in the platform denticulation is an important evolutionary trend, three new genera are proposed: Guexispathodus n. gen., Marquezella n. gen., and Kirilella n. gen., which, together with Pseudofurnishius and Mosherella, represent the subfamily Marquezellinae n. subfam.

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Smithian conodonts on Kotelny Island (Novosibirsk Islands) were reported by Klets and Yadrenkin ( 2001) as exclusively segminiplanate.The presence of segminiplanate morphs in the boreal zone contrasts with that of the segminate genus Neospathodus in cherty deep waters of the Russian Far East (Buryi, 1989;Bragin, 1991;Klets, 1998).The new genus described herein comprises the Griesbachian-Dienerian Siberigondolella griesbachensis (Orchard) and Dienerian S. mongeri (Orchard), the Dienerian-Smithian S. composita (Dagys), and the Smithian S. altera (Klets), S. sibirica (Dagys), and S. jakutensis (Dagys).