eesti teaduste
akadeemia kirjastus
SINCE 1952
Earth Science cover
Estonian Journal of Earth Sciences
ISSN 1736-7557 (Electronic)
ISSN 1736-4728 (Print)
Impact Factor (2020): 0.789

Phosphatized organic nanostructures in the Cambrian linguloid brachiopod Ungula inornata (Mickwitz); pp. 121–130

Full article in PDF format | doi: 10.3176/earth.2013.10

Liisa Lang, Ivar Puura†


Scanning electron microscopy of untreated and uncoated fracture sections of a secondary shell of a Cambrian (Furongian) linguloid brachiopod Ungula inornata (Mickwitz) in concurrent backscattered electron and secondary electron imaging regimes revealed phosphatized organic fibril-like nanostructures, less than 200 nm in diameter. By analogy with published data on a living lingulate genus Discinisca, the nanofibrils are interpreted as parts of the organic biopolymer matrix, which are composed of axial protein strands of bacula connected by chitin and participate in the formation of baculate sets. The nanofibrils are relevant structural units in the hierarchical structure of lingulate brachiopods with baculate shell structure. It is concluded that these structures are preserved by instant post-mortem precipitation of apatite. The shell structure of U. inornata is most similar to the other species of the genus Ungula Pander and the species of the genus Obolus Eichwald.


Artyushkov, E. V., Lindström, M. & Popov, L. E. 2000. Relative sea level changes in Baltoscandia in the Cambrian and Early Ordovician: the predominance of tectonic factors and the absence of large scale eustatic fluctuations. Tectonophysics, 320, 375–407.

Batrukova, L. S. 1969. Novye devonskie lingulidy i distsinidy Russkoj Platformy [New Devonian lingulids and discinids from the Russian Platform]. Vsesoyznyj Nauchno-Issledovatel¢skij Geologo-Razvedochnyj Neftyanoj Institut, Trudy, 93, 59–77 [in Russian].

Bruguière, J. G. 1797. Vers, Coquilles, Mollusques et Polypiers. Tableau encyclopédique et méthodique des trios règnes de la nature, 2, 96–314. Agasse, Paris.

Cocks, L. R. M. & Torsvik, T. H. 2005. Baltica from the late Precambrian to mid-Palaeozoic times: the gain and loss of a terrane’s identity. Earth-Science Reviews, 72, 39–66.

Cusack, M., Williams, A. & Buckman, J. O. 1999. Chemico-structural evolution of linguloid brachiopod shells. Palaeontology, 42, 799–840.

Dall, W. H. 1870. A revision of the Terebratulidae and Lingulidae, with remarks on and descriptions of some recent forms. American Journal of Conchology, 6, 88–168.

Duméril, A. 1806. Zoologie analytique ou méthode naturelle de classification des animaux. Allais, Paris, xxiv + 344 pp.

Eichwald, E. 1829. Zoologia specialis, quam expositis animalibus tum vivis, tum fossilibus potissimim Rossiae in universum et Poloniae in specie in usum lectionum publicarum in Universitate Caesarea Vilnesi, 1, Josephi Zawadski, Vilnae. 314 pp.

Emig, C. C. 2002. Tools for linguloid taxonomy: the genus Obolus (Brachiopoda) as an example. Carnets de Géologie / Notebooks on Geology, Maintenon, Article 2002/01 (CG2002_A01_CCE), 1–9.

Goryanskij, V. Yu. 1969. Bezzamkovye brakhiopody kembrijskikh i ordovikskikh otlozhenij severo-zapada Russkoj platformy [Inarticulate Brachiopods of the Cambrian and Ordovician of the Northwest Russian Platform]. Materialy po geologii i poleznym iskopaemym severo-zapada RSFSR 6 [Materials on the geology and mineral resources of the North-West of the Russian Platform 6]. Nedra, Leningrad, 176 pp. [in Russian].

Goryanskij, V. Yu. & Popov, L. E. 1985. Goryanskij, V. J. & Popov, L. E. 1985. Morphologiya, sistematicheskoe polozhenie i proiskhozhdenie bezzamkovykh brakhiopod s karbonatnoj rakovinoj [Morphology, systematic position and origin of inarticulate brachiopods with a carbonate shell]. Paleontologicheskij Zhurnal, 3, 3–14 [in Russian].

Graham, D. K. 1970. Scottish Carboniferous lingulacea. Bulletin of the Geological Survey of Great Britain, 31, 139–184.

Heinsalu, H., Viira, V., Mens, K., Oja, T. & Puura, I. 1987. The section of the Cambrian–Ordovician boundary beds in Ülgase, northern Estonia. Eesti NSV Teaduste Akadeemia Toimetised, Geoloogia, 36, 154–165 [in Russian, with English summary].

Holmer, L. E. 1989. Middle Ordovician phosphatic inarticulate brachiopods from Västergötland and Dalarna, Sweden. Fossils and Strata, 26, 1–172.

Khazanovitch, K. K., Popov, L. E. & Mel¢nikova, L. M. (eds). 1984. Bezzamkovye brakhiopody, ostrakody (bradoriidy) i khiolitel¢minty iz sablinskoj svity Leningradskoj oblasti [Inarticulate brachiopods, ostracodes (bradoriids) and hyolithelminths from the Sablinka Formation of the Leningrad District]. Paleontologicheskij Zhurnal, 1984(4), 33–47 [in Russian].

King, W. 1846. Remarks on certain Genera belonging to the Class Palliobranchiata. Annals and Magazine of Natural History (London) (Series 1), 18, 26–42, 83–94.

Koneva, S. P. & Popov, L. E. 1983. Nekotorye novye lingulidy iz verkhnego kembriya i nizhnego ordovika Malogo Karatau [On some new lingulids from the Upper Cambrian and Lower Ordovician of Malyi Karatau]. In Stratigrafiya i Paleontologiya Nizhnego Paleozoya Kazakhstana [The Lower Palaeozoic Stratigraphy and Palaeontology of Kazakhstan] (Apollonov, M. K., Bandaletov, S. M. & Ivshin, N. K.), pp. 112–124. Nauka, Leningrad [in Russian].

Kutorga, S. S. 1837. Zweiter Beitrag zur Geognosie und Palaeontologie Dorpats und seiner nähsten Umgebungen. St. Petersburg, 51 pp.

Lang, L. & Puura, I. 2009. Systematic position, distribution, and shell structure of the Devonian linguloid brachiopod Bicarinatina bicarinata (Kutorga, 1837). Estonian Journal of Earth Sciences, 58, 63–70.

Lang, L., Uibopuu, E. & Puura, I. 2011. Nanostructures in Palaeozoic lingulate brachiopods. Memoirs of the Association of Australasian Palaeontologists, 41, 359–366.

Loog, A. & Kivimägi, E. 1968. On the lithostratigraphy of the Pakerort Stage in Estonia. Eesti NSV Teaduste Akadeemia Toimetised, Keemia, Geoloogia, 17, 374–385 [in Russian, with English summary].

Menke, C. T. 1828. Synopsis methodica molluscorum generum omnium et specierum earum quae in Museo Menkeano adservantur. G. Uslar, Pyrmonti, 91 pp.

Mens, K., Viira, V. & Puura, I. 1989. Cambrian–Ordovician boundary beds at Mäekalda, Tallinn, North Estonia. Proceedings of the Estonian Academy of Sciences, Geology, 38, 101–111.

Merkel, C., Griesshaber, E., Kelm, K., Neuser, R., Jordan, G., Logan, A., Mader, W. & Schmahl, W. W. 2007. Micro­mechanical properties and structural characterization of modern inarticulated brachiopod shells. Journal of Geophysical Research, 112, G02008.

Mickwitz, A. 1896. Über die Brachiopodengettung Obolus Eichwald. Memoires de l’Académie Impériale des Sciences de St. Pétersbourg, 4, 1–215.

Mickwitz, A. 1909. Vorläufige Mitteilung über das genus Pseudolingula Mickwitz. Mémoires de l’Académie Impériale des sciences de St. Pétersbourg (series 6), 3, 765–772.

Moberg, J. C. & Segerberg, C. O. 1906. Bidrag till kännedomen om ceratopygeregionen med särskild hänsyn till dess utveckling i Fågelsångstrakten. Lunds Universitets Ǻrsskrift N.F.2, 2, 1–116.

Nemliher, J. 2006. A new type of shell structure in a phosphatic brachiopod from the Cambrian of Estonia. Proceedings of the Estonian Academy of Sciences, Geology, 55, 259–268.

Nemliher, J., Kurvits, T., Kallaste, T. & Puura, I. 2004. Apatite varieties in the shell of the Cambrian lingulate brachiopod Obolus apollinis Eichwald. Proceedings of the Estonian Academy of Sciences, Geology, 53, 246–256.

Pander, C. H. 1830. Beiträge zur Geognosie des Russischen Reiches. St Petersburg, 165 pp.

Popov, L. E. & Khazanovitch, K. K. 1989. Popov, L. E. & Khazanovitch, K. K. 1989. Lingulaty (bezzamkovye brakhiopody s fosfatnokal´tsievoj rakovinoj) [Lingulates (inarticulate brachiopods with calcium-phosphatic shell]. In Opornye razrezy i stratigrafiya kembro-ordovikskoj fosforitonosnoj obolovoj tolshchi na severo-zapade Russkoj platformy [The Key Sections and Stratigraphy of the Phosphate-Bearing Obolus Beds on the North-East of the Russian Platform] (Popov, L. E., Khazanovitch, K. K., Borovko, N. G., Sergeeva, S. P. & Sobolevskaya, R. F.), AN SSSR, Ministerstvo Geologii SSSR, Mezhvedomstvennyj Stratigraficheskij Komitet SSSR, Trudy, 18, 96–136 [in Russian].

Popov, L. E. & Holmer, L. E. 2003. Understanding linguloid brachiopods: Obolus and Ungula as examples. Carnets de Géologie / Notebooks on Geology, Maintenon, Article 2003/06 (CG2003_A06_LEP-LEH), 1–13.

Popov, L. E., Khazanovitch, K. K., Borovko, N. G., Sergeeva, S. P. & Sobolevskaya, P. F. 1989. Opornye razrezy i stratigrafiya kembro-ordovikskoj fosforitonosnoj obolovoj tolshchi na severo-zapade Russkoj platformy [The key sections and stratigraphy of the phosphate-bearing Obolus beds in the north-east of the Russian Platform]. AN SSSR, Ministerstvo Geologii SSSR, Mezhvedomstvennyj Strati­graficheskij Komitet SSSR, Trudy, 18, 1–222 [in Russian].

Puura, I. 2000. Iru section. In Geophysics in the Baltic Region: Problems and Prospects for the New Millennium. International Conference: Abstracts & Excursion Guide (Shogenova, A. & Vaher, R., compilers), pp. 107–108. Tallinn, Estonia.

Puura, I. 2004. The shelly phosphorite of Estonia: the Ülgase outcrop. In The Eighth Marine Geological Conference: Abstracts, Excursion Guide (Puura, I., Tuuling, I. & Hang, T., eds), pp. 75–78. The Baltic, Tartu.

Puura, I. & Holmer, L. E. 1993. Lingulate brachiopods from the Cambrian–Ordovician boundary beds in Sweden. Geologiska Föreningens i Stockholm, Förhandlingar, 115, 215–237.

Puura, I. & Viira, V. 1999. Chronostratigraphy of the Cambrian–Ordovician boundary beds in Baltoscandia. Acta Universitatis Carolinae Geologica, 43, 5–8.

Puura, I. & Viira, V. 2004. Tracing the base of the Ordovician System in Baltoscandia. In WOGOGOB-2004 Conference Materials (Hints, O. & Ainsaar, L., eds), pp. 85–86. Tartu University Press, Tartu.

Schmahl, W. W., Griesshaber, E., Merkel, C., Kelm, K., Deuschle, J., Neuser, R. D., Göetz, A. J., Sehrbrock, A. & Mader, M. 2008. Hierarchical fibre composite structure and micromechanical properties of phosphatic and calcitic brachiopod shell biomaterials – an overview. Mineralogical Magazine, 72, 541–562.

Schuchert, C. & LeVene, C. M. 1929. Brachiopoda (Generum et genotyporum index et bibliographia). Fossilum Catalogus, 1 – Animalia, Pars 42. Berlin, 140 pp.

Ulrich, E. O. 1889. On Lingulasma, a new genus, and eight new species of Lingula and Trematis. American Geologist, 3, 377–391.

Waagen, W. 1885. Salt Range Fossils, Vol. I, part 4. Productus-Limestone Fossils, Brachiopoda. Memoirs of the Geological Survey of India, Palaeontologia Indica (Series 13), 5, 729–770.

Walcott, C. D. 1912. Cambrian Brachiopoda. Monograph of the U.S. Geological Survey, 51, 1–182.

Williams, A. & Cusack, M. 1999. Evolution of a rhythmic lamination in the organophosphatic shells of brachiopods. Journal of Structural Biology, 126, 227–240.

Williams, A. & Cusack, M. 2007. Chemicostructural diversity of the brachiopod shell. In Treatise on Invertebrate Paleontology, Part H, Brachiopoda Revised, 6, Supplement (Selden, P. A., ed.), pp. 2396–2521. Geological Society of America, Boulder and University of Kansas, Lawrence.

Williams, A., Carlson, S. J., Brunton, C. H. C., Holmer, L. E. & Popov, L. E. 1996. A supra-ordinal classification of the Brachiopoda. Philosophical Transactions of the Royal Society of London (series B), 351, 1171–1193.

Williams, A., Cusack, M. & Buckman, J. O. 1998. Chemico-structural phylogeny of the discinoid brachiopod shell. Philosophical Transactions of the Royal Society of London (series B), 353, 2005–2038.

Back to Issue