Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-23T14:29:43.437Z Has data issue: false hasContentIssue false

The distribution and inferred larval dispersion of Rhondellina dorei: a new Cambrian brachiopod (Acrotretida)

Published online by Cambridge University Press:  14 July 2015

A. J. Rowell*
Affiliation:
Department of Geology and Museum of Invertebrate Paleontology, University of Kansas, Lawrence 66045

Abstract

Rhondellina dorei n. gen., n. sp. is morphologically a very unusual acrotretid in possessing a marginal ventral beak and vestigial ventral pseudointerarea. In common with all other acrotretaceans it has a pitted first-formed shell that is an evolutionary novelty for the clade. By analogy with developmental stages of living lingulids and discinids it is concluded that these pitted first-formed valves are not protegula, but are larval valves developed during a protracted pelagic phase. The distinction is important in considering dispersal of the organisms. Although some acrotretids are endemic and limited to rocks deposited around a single Cambrian continental landmass, others are cosmopolitan. The wide dispersal of such forms supports earlier conclusions that the functional significance of the pits in the larval valves was an adaptation to increase buoyancy and suggests that the larvae were planktotrophic. Because of energy problems inherent with planktotrophic larvae and small parents, it is conceivable that acrotretacean development was mixed and that a relatively small number of lecithotrophic eggs were brooded prior to release of the free-swimming planktotrophs.

Rhondellina dorei was seemingly endemic to Cambrian North America. Although its larvae apparently were unable to cross oceanic barriers, the species dispersed around the periphery of the craton. It is known from western Utah and eastern Nevada and also occurs in Peary Land, North Greenland, on the opposing side of the continent. In the western United States it occurs only in the Crepicephalus Zone (lower Dresbachian, Upper Cambrian), but in Greenland it appears earlier in the upper Lejopyge laevigata Zone, in beds that are the temporal equivalents of the North American Cedaria Zone.

Type
Research Article
Copyright
Copyright © The Paleontological Society 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bambach, R. K., Scotese, C. R. and Ziegler, A. M. 1980. Before Pangea: the geographies of the Paleozoic world. American Scientist, 68:2638.Google Scholar
Biernat, G. and Williams, A. 1970. Ultrastructure of the protegulum of some acrotretide brachiopods. Palaeontology, 13:491502.Google Scholar
Boucot, A. J. and Gray, J. 1979. Epilogue: a Paleozoic Pangea?, p. 465482. In Boucot, A. J. and Gray, J. (eds.), Historical Biogeography, Plate Tectonics, and the Changing Environment. Oregon State University Press, Corvallis.Google Scholar
Caswell, H. 1981. The evolution of “mixed” life histories in marine invertebrates and elsewhere. American Naturalist, 117:529536.CrossRefGoogle Scholar
Chuang, S. H. 1962. Statistical study of variations in the shell of Lingula unguis (L.). Videnskabelige Meddelelser fra Dansk Naturhistorisk Forening i Kobenhavn., 124:199215.Google Scholar
Chuang, S. H. 1977. Larval development in Discinisca (inarticulate brachiopod). American Zoologist, 17:3953.CrossRefGoogle Scholar
Daily, B. and Jago, J. B. 1975. The trilobite Lejopyge Hawle and Corda and the Middle–Upper Cambrian boundary. Palaeontology, 18:527550.Google Scholar
Hammond, L. S. 1980. The larvae of a discinid (Brachiopoda: Inarticulata) from inshore waters near Townsville, Australia, with revised identifications of previous records. Journal of Natural History, 4:647661.CrossRefGoogle Scholar
Hammond, L. S. 1982. Breeding season, larval development and dispersal of Lingula anatina (Brachiopoda, Inarticulata) from Townsville, Australia. Journal of the Zoological Society of London, 198:183196.CrossRefGoogle Scholar
Henderson, R. A. 1974. Shell adaptation in achrothelid [acrothelid] brachiopods to settlement on a soft substrate. Lethaia, 7:5761.CrossRefGoogle Scholar
Ineson, J. R. and Peel, J. S. 1980. Cambrian stratigraphy in Peary Land, eastern North Greenland. Groenlands Geologiske Undersoegelse, Rapport 99:3342.CrossRefGoogle Scholar
Jablonski, D. and Lutz, R. A. 1983. Larval ecology of marine benthic invertebrates: paleobiological implications. Biological Reviews, 58:2189.CrossRefGoogle Scholar
Ludvigsen, R. 1974. A new Devonian acrotretid (Brachiopoda, Inarticulata) with unique protegular ultrastructure. Neues Jahrbuch für Geologie und Paleontologie, Monatshefte 1974:3:133148.Google Scholar
Nazarov, B. B. and Popov, L. E. 1980. Stratigraphy and fauna of Ordovician siliceous–carbonate deposits of Kazakhstan (in Russian).Google Scholar
Stratigrafiya i fauna Kreminsto–Carbonatnykh Tolshch Ordovika Kazakhstana. Ordena Trudovogo Krasnogo Znameni Geologicheskij Institut, A.N., 331:3190.Google Scholar
Paine, R. T. 1963. Ecology of the brachiopod Glottidia pyramidata. Ecological Monographs, 33:187213.CrossRefGoogle Scholar
Pechenik, J. A. 1979. Role of encapsulation in invertebrate life histories. American Naturalist, 114:859870.CrossRefGoogle Scholar
Peel, J. S. 1979. Cambrian–Middle Ordovician stratigraphy of the Adams Gletscher region, southwest Peary Land, North Greenland. Groenlands Geologiske Undersoegelse, Rapport 88:2939.CrossRefGoogle Scholar
Peel, J. S. 1982. The Lower Paleozoic of Greenland, p. 309330. In Embry, A. F. and Balkwill, H. R. (eds.), Arctic Geology and Geophysics. Canadian Society of Petroleum Geologists, Memoir 8.Google Scholar
Pel'man, Yu. L. 1977. Early and Middle Cambrian brachiopods of the Siberian Platform (in Russian). Rannie Srednekembrijskie Bezzamkovye Sibirskoj Platformy. Trudy Instituta Geologii i Geofiziki, Sibirskoe Otdelenie, A.N., 316:1167.Google Scholar
Poulsen, V. 1971. Notes on an Ordovician acrotretacean brachiopod from the Oslo region. Bulletin of the Geological Society of Denmark, 20:265278.Google Scholar
Robison, R. A. 1984. Cambrian Agnostida from North America and Greenland: Part 1, Ptychagnostidae. University of Kansas Paleontological Contributions, Paper 109:159.Google Scholar
Rowell, A. J. 1965. Inarticulata, p. H260–H296. In Moore, R. C. (ed.), Treatise on Invertebrate Paleontology, (H) Brachiopoda. Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Rowell, A. J. 1977. Early Cambrian brachiopods from the southwestern Great Basin of California and Nevada. Journal of Paleontology, 51:6885.Google Scholar
Rowell, A. J. 1981. Inarticulate brachiopods of the Lower and Middle Cambrian Pioche Shale of the Pioche District, Nevada. University of Kansas Paleontological Contributions, Paper 98:126.Google Scholar
Scheltema, R. S. 1977. Dispersal of marine invertebrate organisms: paleobiogeographic implication, p. 73108. In Kauffman, E. G. and Hazel, J. E. (eds.), Concepts and Methods in Biostratigraphy. Dowden, Hutchinson and Ross, Inc., Stroudsburg, Pennsylvania.Google Scholar
Thorson, G. 1950. Reproductive and larval ecology of marine bottom invertebrates. Biological Reviews, 25:145.CrossRefGoogle ScholarPubMed
Valentine, J. W. and Jablonski, D. 1983. Larval adaptations and patterns of brachiopod diversity in space and time. Evolution, 37:10521061.CrossRefGoogle ScholarPubMed
von Bitter, P. and Ludvigsen, R. 1979. Formation and function of protegular pitting in some North American acrotretid brachiopods. Palaeontology, 22:705720.Google Scholar
Westergard, A. H. 1946. Agnostidea of the Middle Cambrian of Sweden. Sveriges Geologiska Undersoekning, (C) 477:1141.Google Scholar
Williams, S. H. and Lockley, M. G. 1983. Ordovician inarticulate brachiopods from graptolitic shales at Dobb's Linn; their morphology and significance. Journal of Paleontology, 57:391400.Google Scholar