Fig. 2

Jurassic ammonites from West Siberian wells. 1 Kepplerites sp., TSOGU (there are no specimen numbers), Yendyrskaya 10 well (2918.1 m), Lower Callovian. 2 Kosmoceras sp. juv. (×6), TSOGU, Severo-Pyamyaliakhskaya 31 well (3298.8). Middle-Upper Callovian; 2a lateral view, 2b ventral view (refigured from Vyachkileva et al. 1990, pl. 43, fig. 6). 3 Kosmocers sp., TSOGU, Snegirinaya 291 well (2644.7 m), Middle-Upper Callovian (Coronatum-Athleta Zones). 4 Longaeviceras cf. keyserlingi (Sokolov), TSOGU, Rogozhnikovskaya 713 well (2586 m), Upper Callovian, Keyserlingi Zone. 5 Quenstedtoceras lamberti (Sowerby), TSOGU, Fedyushkinskaya 6 well (2896.1 m), Upper Callovian, Lamberti Zone. 6 Cardioceras densiplicatum Boden, TSOGU, Larlomkinskaya 18 well (2524.3 m), Middle Oxfordian, Densiplicatum Zone; 6a lateral view, 6b ventral view, 6c cross section. 7, 8 TSOGU, Otor’inskaya 42 well (60.6 m), Lower Kimmeridgian, ? Bauhini/Kitchini Zone; 7 Amoeboceras (Plasmatites/Amoebites) sp. juv. (×5) 7a ventral view, 7b cross section. 8 Amoeboceras (Plasmatites) gerassimovi (Kalacheva et Mesezhnikov), 8a lateral view, 8b ventral view. 9 Amoebites subkitchini Spath, TSOGU, Yumantylskaya 925 well (3442 m), Lower Kimmeridgian, Kitchini Zone. 10 Rasenia cf. optima Mesezhnikov, TSOGU, Spasskaya 21 well (2880.2 m), Lower Kimmeridgian, Evoluta Zone. 11 Pavlovia sp., TSOGU, Severo-Demyanskaya 2 well (2873.9 m), Middle Volgian, Iatriensis Zone. 12 Dorsoplanites cf. maximus (Spath), IPGG SB RAS, Druzhnaya 161 well (2865–2875 m), Middle Volgian, Maximus Zone. 13, 14 Laugeites sp. ind., IPGG SB RAS, Lontynyakhskaya 69 well (2518.5; 2518.3 m), Middle Volgian, Beds with L. groenlandicus—Vogulicus Zone