The first discovery leaves of angiosperms in the Middle Jurassic deposits in Eastern Siberia

Proceedings of the VII International Scientific Conference, dedicated to the 135th anniversary of the P.N. Krylov Herbarium of Tomsk State University and the 170th anniversary of P.N. Krylov ◽

10.17223/978-5-94621-927-3-2020-42 ◽

2020 ◽

Author(s):

А.О. Frolov ◽

◽

I.V. Enushchenko ◽

Keyword(s):

Middle Jurassic ◽

Eastern Siberia ◽

Coal Basin ◽

Anomocytic Stomata ◽

Irkutsk Coal Basin

There is fossil of linear whole-marginal leaves with parallel venation in the Middle Jurassic (Aalenian) sediments of the Irkutsk Coal Basin, were found. During the study of cuticle preparations it was found that leaves were steam-bearing, has anastomoses between veins, anomocytic stomata and the diamond-shaped main cells of the epidermis. Such a combination of characters is widespread in modern monocotyledonous and is absent among fossil as well as modern sporeals and gymnosperms plants. We have every reason to believe that we have found unique structures of leaves characteristic of monocotyledons. This find is the oldest among the herbaceous angiosperms of the Jurassic period, such as Yuraherba and Yukhaniya, and the first found in Siberia.

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Sorosaccus sibiricus Prynada (Ginkgoales) from the Middle Jurassic deposits of the Irkutsk Coal Basin, Eastern Siberia

Palaeobotany ◽

10.31111/palaeobotany/2018.9.5 ◽

2018 ◽

Vol 9 ◽

pp. 5-17

Author(s):

N. V. Nosova ◽

N. M. Zavialova ◽

A. I. Kiritchkova ◽

E. I. Kostina

Keyword(s):

Middle Jurassic ◽

Pollen Grains ◽

Eastern Siberia ◽

Coal Basin ◽

New Findings ◽

Irkutsk Coal Basin ◽

First Time

New findings of pollen cones of Sorosaccus sibiricus Prynada were studied in detail from the Aalenian—Bajocian Prisayan Formation of two localities in the Irkutsk coal basin (Ust’-Baley and Vladimirovka). Specimens of S. sibiricus previously described from Ust’-Baley (Heer, 1876) were reexamined. It was revealed that S. sibiricus differs from other species of Sorosaccus in a shape of the apical (free from the microsporangia) part of the microsporophylls. Microsporophylls of S. sibiricus consist of a petiole and a wide-oval distal lamina with acute apex, commonly bending upward. The lamina was often folded and became lanceolate, linear, or fan-shaped with uneven to toothed margin. Microsporangia (6—8) are oval in outline, helically attached to the petiole. Pollen grains were extracted from S. sibiricus microsporangia for the first time. They are oval to boat-shaped in outline, monosulcate and differ from other known Sorosaccus pollen grains by the verrucate surface of the exine. The diagnosis of the species Sorosaccus sibiricus is emended.

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A New Species of Marskea Florin (Pinopsida) from the Middle Jurassic of the Irkutsk Coal Basin (East Siberia)

Paleontological Journal ◽

10.1134/s0031030118050106 ◽

2018 ◽

Vol 52 (5) ◽

pp. 574-581

Author(s):

N. V. Nosova ◽

A. I. Kiritchkova

Keyword(s):

New Species ◽

Middle Jurassic ◽

East Siberia ◽

Coal Basin ◽

Irkutsk Coal Basin ◽

A New Species

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Revision of existing classification of fossil insect feeding traces and description of new ichnotaxa from Middle Jurassic sediments of Eastern Siberia (Russia)

Zootaxa ◽

10.11646/zootaxa.4758.2.8 ◽

2020 ◽

Vol 4758 (2) ◽

pp. 347-359

Author(s):

ILYA V. ENUSHCHENKO ◽

АNDREY O. FROLOV

Keyword(s):

Middle Jurassic ◽

Egg Laying ◽

Zoological Nomenclature ◽

Eastern Siberia ◽

Fossil Plants ◽

Insect Feeding ◽

Fossil Insect ◽

Formal Classification ◽

Irkutsk Coal Basin

This paper revises the existing system of formal classification by Vialov and Vasilenko for fossil plants involving insect feeding and oviposition. The classification of these fossil traces has been amended and supplemented in accordance with the requirements of the International Code of Zoological Nomenclature. The following nomenclatural combinations are made: Insectophagichnata (Vialov) Enushchenko and Frolov, comb. et stat. (classis) nov., Phagolignichnidina (Vialov) Enushchenko and Frolov, comb. et stat. (subordo) nov., Phagophytichnidina (Vialov) Enushchenko and Frolov, comb. et stat. (subordo) nov. Fossil traces of these interactions were found and illustrated for Mesozoic insects and leafes of Ginkgo tapkensis from Middle Jurassic sediments of the Irkutsk Coal Basin in Eastern Siberia, Russia. The examined traces consist of ovipositions (traces of insect egg laying), galls (traces of insect caused teratologies) and epidermal punctures (traces of piercing and sucking). The following ichnotaxa are described and illustrated: Paleoovidinae Enushchenko and А. Frolov, ichnosubfam. nov., Paleoexoovoidinae Enushchenko and Frolov, ichnosubfam. nov., Sugophytichninae Enushchenko and А. Frolov, ichnosubfam. nov., Sugophytichnida pertusura Enushchenko and Frolov, ichnogen. et ichnospec. nov., Paleoovidus vasilenkoi Enushchenko and А. Frolov, ichnospec. nov., Paleoexoovoida ovoidea Enushchenko and А. Frolov, ichnogen. et ichnosp. nov., Paleogallus vialovi Enushchenko and Frolov, ichnospec. nov. Punctures of the leaf epidermis probably belong Mesozoic cicadas of the Palaeontini, which dominate the adjacent strata of the studied location. The extremely low occurrence of interaction between insects and plants in these Jurassic deposits of Eastern Siberia have ichnotaxonomic importance for understanding the functioning of Jurassic terrestrial paleoecosystems.

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