Research output: Contribution to journal › Article › peer-review
Early Eukaryotes in the Lakhanda Biota (Mesoproterozoic, Southeastern Siberia)—Morphological and Geochemical Evidence. / Shuvalova, J. V.; Nagovitsin, K. E.; Duda, J. P. et al.
In: Doklady Biological Sciences, Vol. 500, No. 1, 3, 09.2021, p. 127-132.Research output: Contribution to journal › Article › peer-review
}
TY - JOUR
T1 - Early Eukaryotes in the Lakhanda Biota (Mesoproterozoic, Southeastern Siberia)—Morphological and Geochemical Evidence
AU - Shuvalova, J. V.
AU - Nagovitsin, K. E.
AU - Duda, J. P.
AU - Parkhaev, P. Yu
N1 - Funding Information: The research was supported by the Russian Foundation for Basic Research (project no. 17-54-12077), the German Research Foundation (DFG) (project nos. DU 1450/4-1 and DU 1450/5-1). Publisher Copyright: © 2021, Pleiades Publishing, Ltd.
PY - 2021/9
Y1 - 2021/9
N2 - The Mesoproterozoic Lakhanda Group (~1030 Ma) preserves one of the most diverse communities of pre-Ediacaran eukaryotes. More precisely, the Lakhanda Biota includes more than twenty taxa that have been assigned to eukaryotes with different degrees of confidence. Eight of these taxa meet current criteria for the identification of eukaryotic fossils in ancient records. These include previously described fossils such as ornamented acritarchs (Valeria lophostriata, Trachyhystrichosphaera aimika), filamentous coenocytic organisms (Aimonema ramosa, Palaeovaucheria clavata), as well as fossils with smooth-walled envelopes and single outgrowth structures (Caudosphaera expansa, Germinosphaera bispinosa, and Jacutianema solubila). In addition to these, we found as yet undescribed fossils which share remarkable similarities with Ourasphaira giraldae, a possible higher fungi species known from the (?) Meso- to Neoproterozoic of Arctic Canada. Regardless of the exact systematic affinity, these fossils can confidently be assigned to eukaryotes because of the size and high morphological complexity. Intriguingly, the organic record of the Lakhanda Formation lacks biomarkers indicative of eukaryotes (that is, regular steranes). This finding would be in line with the idea that eukaryotes were present but not significant in Mesoproterozoic marine ecosystems. However, preliminary data from an ongoing study indicate an advanced thermal maturity of the organic matter, emphasizing that this conclusion might not be drawn with absolute confidence.
AB - The Mesoproterozoic Lakhanda Group (~1030 Ma) preserves one of the most diverse communities of pre-Ediacaran eukaryotes. More precisely, the Lakhanda Biota includes more than twenty taxa that have been assigned to eukaryotes with different degrees of confidence. Eight of these taxa meet current criteria for the identification of eukaryotic fossils in ancient records. These include previously described fossils such as ornamented acritarchs (Valeria lophostriata, Trachyhystrichosphaera aimika), filamentous coenocytic organisms (Aimonema ramosa, Palaeovaucheria clavata), as well as fossils with smooth-walled envelopes and single outgrowth structures (Caudosphaera expansa, Germinosphaera bispinosa, and Jacutianema solubila). In addition to these, we found as yet undescribed fossils which share remarkable similarities with Ourasphaira giraldae, a possible higher fungi species known from the (?) Meso- to Neoproterozoic of Arctic Canada. Regardless of the exact systematic affinity, these fossils can confidently be assigned to eukaryotes because of the size and high morphological complexity. Intriguingly, the organic record of the Lakhanda Formation lacks biomarkers indicative of eukaryotes (that is, regular steranes). This finding would be in line with the idea that eukaryotes were present but not significant in Mesoproterozoic marine ecosystems. However, preliminary data from an ongoing study indicate an advanced thermal maturity of the organic matter, emphasizing that this conclusion might not be drawn with absolute confidence.
KW - biomarkers
KW - eukaryotes
KW - Lakhanda biota
KW - Mesoproterozoic
KW - Biological Evolution
KW - Geologic Sediments
KW - Eukaryota
KW - Biota
KW - Ecosystem
KW - Siberia
KW - Fossils
UR - http://www.scopus.com/inward/record.url?scp=85118706339&partnerID=8YFLogxK
UR - https://www.mendeley.com/catalogue/7b578dc4-df23-3701-a05e-a2c878e98b6a/
U2 - 10.1134/S0012496621050100
DO - 10.1134/S0012496621050100
M3 - Article
C2 - 34731376
AN - SCOPUS:85118706339
VL - 500
SP - 127
EP - 132
JO - Doklady Biological Sciences
JF - Doklady Biological Sciences
SN - 0012-4966
IS - 1
M1 - 3
ER -
ID: 34641524