Paleontological Contributions
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THE UNIVERSITY OF KANSAS PALEONTOLOGICAL CONTRIBUTIONS May 16, 1978 Paper 90 REVISION OF A LATE MIDDLE CAMBRIAN TRILOBITE FAUNULE FROM NORTHWESTERN QUEENSLAND' P. A. JELL and R. A. ROBISON University of Queensland, St. Lucia, Queensland, and University of Kansas, Lawrence ABSTRACT Three species, each belonging to a different genus, are shown to be represented by previously figured types of Euagnostus opimus Whitehouse, 1936, which is the nominate species of the commonly cited Euagnostus opimus Zone in Australia. The holotype of E. opimus is here reassigned to Peronopsis Corda, 1847, and Euagnostus Whitehouse, 1936, is thereby suppressed as a subjective junior synonym of Peronopsis. This action necessitates a change in biostratigraphic terminology from Euagnostus opimus Zone to Peronopsis opimus Zone. Because of the taxonomic and biostratigraphic importance of these conclusions, all trilobites from the type collection of E. opimus are described or redescribed and evaluated. These include the miorneroids Baltagnostus australis n. sp., Doryagnostus deltoïdes n. sp., Hypagnostus? sp., Opsidiscus micros pinus Jell, and Peronopsis opimus (Whitehouse) as well as the polymeroids Chondranomocare confertum (Whitehouse), Penarosa retif era Opik, Prodamesella biserrata n. sp., and Sudanomocarina changi n. gen. and n. sp. Also, type specimens of Baltagnostus damesi (Resser & Endo) from Manchuria are redescribed and refigured for comparison with B. australis, and a lectotype for B. damesi is designated. INTRODUCTION Euagnostus has been a poorly understood subjective junior synonym of Peronopsis. Figured Middle Cambrian trilobite genus. Its type species, paratypes of E. opimus include a pygidium of a E. opimus, was described in 1936 from north- new species of Baltagnostus Lochman in Lochman western Queensland by the late F. W. White- and Duncan, 1944, and a cephalon of a new house. Recent examination of the type collection species of Doryagnostus Kobayashi, 1939. Revised of E. opimus has led us to the conclusion that the taxonomic assignment of these specimens has ad- holotype and two of Whitehouse's figured para- ditional significance because Opik (1970) has types of E. opimus actually represent three spe- defined an Euagnostus opimus Zone in Australia cies, each belonging to a different genus. We that has been cited in several subsequent publica- have also concluded that the holotype of E. opimus tions (e.g., Hill, Playford, & Woods, 1971; Jell, should be reassigned to Peronopsis Corda (in 1975; Shergold & others, 1976). Because of the Hawle & Corda, 1847), leaving Euagnostus a taxonomic and biostratigraphic importance of 1 Manuscript received June 29, 1977. Whitehouse's material, all trilobites from his 2 The University of Kansas Paleontological Contributions—Paper 90 original collection are described or redescribed field (1959, p. 0117-0126); however, notations and evaluated in this paper. for glabellar segmentation of the polymeroids Whitehouse's collection from the Currant Bush follow Richter and Richter (1940) and some Limestone, which was made in 1932, is housed agnostoid terminology is from Robison (1964). in the Department of Geology and Mineralogy, As used for polymeroids, the term "glabella" in- University of Queensland, and is labeled with cludes the occipital ring. the locality number UQL256. Figured specimens Acknoudedgments.—W. T. Chang of the are entered on the Register of Fossils of the same Nanking Institute of Geology and Palaeontology institution and are identified by numbers with provided photographs of Prodamesella con vexa the prefix UQF. For comparative purposes, a Chang as well as useful correspondence with P. few specimens of Baltagnostus damesi (Resser & A. Jell concerning this faunule. F. J. Collier ar- Endo) are figured from the collections of the U.S. ranged for the loan of specimens from the U.S. Museum of Natural History, Washington, D.C., Museum of Natural History, and A. R. Palmer and these are designated by numbers with the and A. J. Rowell critically reviewed the manu- prefix USNM. script. Research by R. A. Robison was supported Systematic descriptions of the agnostoid trilo- by National Science Foundation grants GA-43723 bites have been prepared by R. A. Robison and and EAR76-10953, and the Wallace E. Pratt Re- those for an eodiscoid and the polymeroids are search Fund, which was provided by Exxon by P. A. Jell. Morphological terms are mostly U.S.A. Foundation and administered by the Uni- those defined by Harrington, Moore, and Stubble- versity of Kansas. LOCALITY The exact location of UQL256 is a subject of Whitehouse's field notes in the Fryer Library some confusion (Fig. 1). In the description of of the University of Queensland clear away some the species, Whitehouse (1936, p. 87) gave as of the confusion. His entry for January 14, 1938, the locality for Euagnostus opimus "the Anomo- explains that since he was last in the area, the care Stage, 52 miles from Camooweal on the Thorntonia homestead had been moved from its road from Camooweal to Thorntonia Station," original location on the main Thornton River and in the section of the same paper titled "Notes to a place on the West Thornton River about on the Faunal Stages" he (p. 76) mentioned that 10 miles upstream from its junction with the the Anomocare Stage "at the road crossing of Thornton. Also, the main Camooweal to Burke- Harris Creek north-east of Camooweal" contained town road had been realigned so as still to pass Anomocare, Euagnostus, Phalacroma, and brachi- by the homestead. These two roads and home- opods. This is basically the fauna of UQL256, stead sites are marked on the Camooweal hut whether or not the type locality of the stage is 1 :253,440 and 1:250,000 geological maps (the old geographically separate from that of Euagnostus road is dashed on these maps). opimus was not indicated. In 1939 Whitehouse On January 15, 1938, Whitehouse wrote that (p. 224) gave as the locality for Anon2ocare he "ran onto Harris Creek (locally called the con fertum "the Anomocare Stage, five miles east Douglas) and followed it down to Undilla." He of Harris Creek on the old main road from also mentioned "Magenta Creek (locally known as Camooweal to Burketown, via Thorntonia Sta- Harris)." A search of the state government maps tion (52 miles from Camooweal)." In the same of the area has shown that these local usages sub- paper (p. 270) he listed the coordinates of the sequently received official recognition. The termi- "road crossing of Harris Creek (Camooweal to nology used by Whitehouse in 1936 and 1939 was Old Thorntonia)" as 138°43' E.; 19°26' S. In used as late as 1951 on a map of the state's stock 1945 (p. 121) he mentioned that Dorypyge tenella routes. However, on the 1960 geological map came from beds "about four miles east of Douglas and the 1968 official parish map, the name of Creek on the old Burketown road. (This locality Harris Creek (with Undilla homestead adjacent) is about three-quarters of a mile west of the type is changed to Douglas Creek and the name of the locality for Anomocare confertum.)" more easterly Magenta Creek is changed to Harris Jell & Robison—Revision of a Trilobite Faunule 3 138°40 E 138°50' E Old ..\Thorntonia 19°25' 19°25' S 19°35' S — 19°35' S SCALE \-\ 0 Miles 5 i 0 Kilometers 8 ( 138°40' E 138°50' E FIG. I. Index map of the Thorntonia area, northwestern Queensland. Creek. Clearly, Whitehouse used the newer east of Bureau of Mineral Resources (BMR) lo- terminology in his 1945 paper. cality 28 marked on the Camooweal Geological The locality 52 miles from Camooweal is Map (same as M28 on Fig. 1), and the sequence about five miles east of Douglas Creek (formerly from the Ptychagnostus atavus to Ptychagnostus Harris Creek). Whitehouse's field notes for a punctuosus zones is known in several northeast later visit (1939) reveal that the position of the to southwest sections across the Currant Bush road crossing quoted for the Anomocare Stage Limestone from BMR locality 28 to as far as five in 1936 is in error. Coordinates quoted refer to miles south of the present Thorntonia homestead. modern Harris Creek (formerly Magenta) on One new species, Sudanomocarina changi, is the old Camooweal to Burketown road, an area not well represented in Whitehouse's collection of almost unfossiliferous and older limestone, of (UQL256), and supplementary material from a lithology quite different (sandy, dolomitic, al- UQL463 has been used to complete the descrip- most massive) from that of the Anomocare Stage. tion. UQL463 is on top of a hill 5.6 km (3.5 mi) One can only assume that the newly noticed south of Thorntonia homestead on the left bank (1937-38 field notebook) changes in geographic of the West Thornton River and has been located names contributed to Whitehouse's error. and recollected by one of us (P.A.J.). It includes Locality UQL256 is, therefore, reasonably well the same fauna as UQL256 but has some addi- identified and a similar fauna has been collected tional species. To complete the revision of ma- by one of us (P.A.J.) from that general area, but terial referred to Euagnostus by Whitehouse the precise location of Whitehouse's collecting (1939, p. 260) a pygidium, UQF69639, from a site is almost impossible to determine because the locality near the Camooweal to Burketown road limestone strata lie almost flat and consequently crossing of V Creek is also described. are widespread. (Indeed, Whitehouse's 1939 field On the Camooweal Geological Map, localities notes mention stopping at several places that he UQL256 and 463 are in the outcrop area of the took to be the type locality, but which turned out Currant Bush Limestone. Locality UQL463 has to be unfossiliferous or to contain a different also been mapped as such by deKeyser and Cook faunule.) The exact location is somewhere just (1972, p.