Abstract
The association of isolated remains of lobopods with a netlike structure, including plates of Microdictyon rozanovi sp. nov. and sclerites with spinelike process of Onychomicrodictyon spiniferum gen. et sp. nov., as well as saberlike sclerites of Protohertzina yudomica sp. nov. interpreted as grasping spines of chaetognaths, is described from the middle part of the Inikan Formation of the Toyonian Stage of the Lower Cambrian (Lermontovia dzevanovskii Zone). The diagnoses and species composition of the genera Microdictyon and Protohertzina are refined.
Similar content being viewed by others
References
S. Bengtson, “The Structure of Some Middle Cambrian Conodonts, and the Early Evolution of Conodont Structure and Function,” Lethaia 9(2), 185–206 (1976).
S. Bengtson, “The Early History of the Conodonta,” Fossils and Strata, No. 15, 5–19 (1983).
S. Bengtson, “Oddballs from the Cambrian Start to Get Even,” Nature 351, 184–185 (1991).
S. Bengtson, Morris S. Conway, B. J. Cooper, et al., Early Cambrian Fossils from South Australia (Assoc. Australas. Paleontol., Brisbane, 1990).
S. Bengtson, S. C. Matthews, and V. V. Missarzhevsky, “The Cambrian Netlike Fossil Microdictyon,” in Problematic Fossil Taxa (Univ. Press, New York, 1986), pp. 97–115.
J. Chen, X. Hou, and H. Lu, “Early Cambrian Netted Scale-Bearing Worm-Like Sea Animal,” Acta Palaeontol. Sin. 28, 1–16 (1989).
J. Chen, G. Zhou, M. Zhu, et al., The Chengjiang Biota: A Unique Window of the Cambrian Explosion (Natl. Museum Nat. Sci., Taichung, Taiwan, 1996).
E. N. K. Clarkson, “The Eye: Morphology, Function, and Evolution,” in Treatise on Invertebrate Paleontology: Part O. Arthropoda 1: Trilobita, Revised (Univ. Kansas Press, Lawrence, 1997), Vol. 1, pp. 114–132.
J. Dzik, “Early Cambrian Lobopodian Sclerites and Associated Fossils from Kazakhstan,” Palaeontology 46 Part 1, 93–112 (2003).
N. V. Esakova and E. A. Zhegallo, Biostratigraphy and Fauna of the Lower Cambrian of Mongolia (Nauka, Moscow, 1996) [in Russian].
R. L. Ethington and D. L. Clark, “Lower and Middle Ordovician Conodonts from the Ibex Area, Western Millard County, Utah,” Brigham Young Univ. Geol. Stud. 28(2), 1–160 (1981).
D. I. Gravestock, E. M. Alexander, Yu. E. Demidenko, et al., The Cambrian Biostratigraphy of the Stansbury Basin, South Australia (MAIK Nauka/Interperiodica, Moscow, 2001).
N. V. Grigorieva, “Skeletal Problematical Organisms,” in Subdivision of the Lower Cambrian of Siberia into Stages: Atlas of Fossils (Nauka, Moscow, 1983), pp. 155–169 [in Russian].
Y. Hao and D. Shu, “The Oldest Known Well-Preserved Phaeodaria (Radiolaria) from Southern Shaanxi,” Geoscience 1(3/4), 301–310 (1987).
I. Hinz, “The Lower Cambrian Microfauna of Comley and Rushton, Shropshire, England,” Palaeontogr. Abt. A 198(1/2), 41–100 (1987).
X. G. Hou and J. Bergström, “Cambrian Lobopodians—Ancestors of Extant Onychophorans?,” Zool. J. Linn. Soc. 114, 3–19 (1995).
A. Yu. Ivantsov, A. Yu. Zhuravlev, V. A. Krassilov, et al., Unique Sinian Localities of Early Cambrian Organisms (Siberian Platform) (Nauka, Moscow, 2005) [in Russian].
V. V. Missarzhevsky, “Paraconodont Organisms from the Cambrian-Precambrian Boundary Beds of the Siberian Platform and Kazakhstan,” in Problems in Paleontology and Biostratigraphy of the Lower Cambrian of Siberia and the Russian Far East (Nauka, Novosibirsk, 1973), pp. 53–57 [in Russian].
V. V. Missarzhevsky, The Earliest Skeletal Fossils and the Stratigraphy of the Precambrian-Cambrian Boundary Beds (Nauka, Moscow, 1989) [in Russian].
V. V. Missarzhevsky and A. M. Mambetov, The Stratigraphy and Fauna of the Cambrian-Precambrian Boundary Beds of the Lesser Karatau Range (Nauka, Moscow, 1981) [in Russian].
K. J. Müller, “Milaculum n. g., ein phosphatisches Microfossil aus dem Altpaläozoikum,” Paläontol. Z. 473(4), 217–228 (1973).
M. N. Nitecki, R. C. Gutschick, and J. E. Repitski, “Phosphatic Microfossils from the Ordovician of the Unites States,” Fieldiana Geol. 35(1), 1–9 (1975).
Yi Qian, “Early Cambrian Small Shelly Fossils of China with Special Reference to the Precambrian-Cambrian Boundary,” in Stratigraphy and Palaeontology of Systemic Boundaries in China: Precambrian-Cambrian Boundary (Univ. Publ. House, Nanjing, 1989), No. 2.
Yi Qian and S. Bengtson, “Palaeontology and Biostratigraphy of the Early Cambrian Meishucunian Stage in Yunnan Province, South China,” Fossils and Strata, No. 24, 156 (1989).
N. P. Suvorova, “The Section of the Lower-Middle Cambrian Boundary Beds of the Yudoma and Inikan Rivers (the Eastern Siberian Platform),” in Biostratigraphy and Fauna of the Lower-Middle Cambrian Boundary Beds of Siberia (Nauka, Novosibirsk, 1983), pp. 49–55 [in Russian].
H. Szaniawski, “Chaetognath Grasping Spines Recognized among Cambrian Protoconodonts,” J. Paleontol. 56(3), 806–810 (1982).
The Cambrian System on the Siberian Platform, Ed. by J. H. Shergold, A. Yu. Rozanov, and A. R. Palmer (IUGS Publ., Trondheim, 1991).
H. Tong, “A Preliminary Study of the Microdictyon from the Lower Cambrian of Zhenba, South Shaanxi,” Acta Micropalaeontol. Sin. 6(1), 97–101 (1989).
Yang Xianhe and He Yuanxiang, “New Small Shelly Fossils from Lower Cambrian Meishucun Stage of Nanjiang Area, Northern Sichuan,” Prof. Pap. Stratigr. Palaeontol. 13, 35–47 (1984).
Author information
Authors and Affiliations
Additional information
Original Russian Text © Yu.E. Demidenko, 2006, published in Paleontologicheskii Zhurnal, 2006, No. 3, pp. 6–14.
Rights and permissions
About this article
Cite this article
Demidenko, Y.E. New Cambrian lobopods and chaetognaths of the Siberian Platform. Paleontol. J. 40, 234–243 (2006). https://doi.org/10.1134/S0031030106030026
Received:
Issue Date:
DOI: https://doi.org/10.1134/S0031030106030026