224 Proc. Japan Acad., 62, Ser. B (1986) [Vol. 62(B),
59. On the Change of Provinciality of the Late Palaeozoic Trilobites in South America
By Teiichi KoBAYASHi, M. J. A., and Takashi HAMADA
(Communicated Sept. 12, 1986)
The Devonian marine sediments are widely distributed in South America not only in the Andean geosyncline but also in the Amazon, Parana and other basins. The Andean sea was extended to the Cape region, Africa through Fauk- land in the early Devonian period, constituting the so-called Malvinokaffric faunal province by Richter (1942) and others. Its trilobite fauna is well charac- terized by preponderance of such endemic genera of the Dalmanitidae and Cal- moniidae attaining some thirty genera and subgenera as shown below:
Dalmanitidae : Andinopyge, Argentopyge, Austral ops, Chamomurus, ? Chiarumanipyge, Fenestraspis, Francovichia, Gamonedaspis. Calmoniidae : Andinacaste, Beinella (Beinella, Belenasps, syn. Paradal- manites), Bouleia, Calmonia, Cryphaeoides, Deltacephalaspis, (D eltacephalaspis, Prestalia), Kozlowskiaspis (Kozlowskiaspis, Romanops), Malvinella, Metacry- phaeus, Parabouleia, Paracalmonia, Pennaia, Phacopidina (syn. Jujuyops), Phacopidina (Vogesina), Probolops, Schizostylus (Schizostylus, Curuyella), Tarijactinoides (syn. Bolivianaspis), Tibagya, Typh.riniscus.
Beside these trilobites there are the so-called boreal-Malvinokaffric genera by Wolfart (1967), namely Leonaspis, Acathopyge, Phacops, Dalmanites, Odon- tochile, Acastoides, Phacopina, Calymene, Dipleura, Burmeisteria, Digonus and Otarion. The Scutelluidae, Cheiruridae, Proetacea exclusive of the Otarionidae, and Harpidae are totally absent in the fauna. This province was probably extended as far as the Ohio mountains, Antarc- tica and Ghana, West Africa as suggested by Burmeisteria (Digonus) antarc- tica Saul, 1965 in the former and Burmeisteria (Digonus) accraensis Saul, 1967 in the latter. The distribution of Digonus is, however, not restricted to the Malvinokaffric provinve. The occurrence of Anchiopella and Synphoria in the Amazon basin shows the commingling of the Appalachian members with the Malvinokaffric fauna. In the Carboniferous period the trilobite fauna of the New World Realm was characterized not only by the lack of Cummingella and Linguaphillipsia, but also by such indigenous genera as Richterella, Exochops, Elliptophillipsia and Breviphillipsia of the Mississippian fauna and Ameura and Sevillia of the Penn- sylvanian fauna. The realm consisted of the North American Mid-Continent province, the Andean geosyncline and the Amazon basin. Australosutura was founded by Amos, Campbell and Goldring (1960) on Cordania gardneri Mitchell, 1922 from the Burindi series, New South Wales. A. argentinensis E. and R. Hahn (1969) is known from the Visean of Chubut province, Argentina. In North America A. strattonportae (Rowley, 1907) oc- curs in the lower Kinderhookian, Missouri, A. georgiana Rich, 1966 in the Osagean, Georgia and A. aff, gartneri in the Mississippian (Visean) of Oklahoma No. 7] Late Palaeozoic Trilobites, South America 225
(Ormiston, 1966) . Judging from these records, this genus appeared first in Missouri, then flourished in the Osagean-Visean in Georgia and Oklahoma, in North America and in Peninsular Argentina in South America. Finally it died out in the Westphalian ( ?) in Australia. Ameura is another trilobite known from the Americas. Its type species is Ameura missouriensis (Shumard, 1858) which is distributed in the Desmo- inseian of Oklahoma and Missouri and the Missourian of Illinois. A. major (Shumard, 1858) is another species widely spread in Colorado, Iowa, Kansas and Missouri from early Desmoinseian to Wolfcampian. In South America the genus is represented by three species, namely, A. tapajotensis (Katzer, 1903), A. duartei (Kegel, 1951) and A. plummeri (Kegel, 1951) in the Upper Carboni- ferous formation in the Amazon region. Little has been known of the Permian trilobites in South America. In Bolivia Branisa (1965) reporte(1 the occurrence of Ditomopyge sp. at Yauri- chambi and Delaria cf. antiqua (Girty) at Apillapampa both in the Lower Permian Copacabana group. Subsequently Arellano (1983) described two new species, Paladin yamupupatensis and Ditomopyge dereimsi, with pygidia respec- tively from Yampupata and Yaueichamba. Recently Kobayashi and Hamada (1986) instituted a new genus, Bolivicrania, for the former species of Arellano, because its cranidia and free cheeks were discovered. It is a highly specialized phillipsid probably derived from the Ditomopyginae stock by isolation. In looking over the South American trilobites in the three late Palaeozoic periods it is found that the Andean sea of the Devonian period constituted the Malvinokaffic province with South Africa. It was expanded to Antarctica on one side and to Ghana through the Amazon-Parana basin on the other side. The trilobites of the province was well characterized by numerous endemic genera. In the Carboniferous periodd the South American trilobite fauna was inti- mately related to that of the Middle Continent of North America on the north side, and Australosutura indicates the route of migration from the Mid-Con- tinent to Eastern Australia through Argentina. The trilobites were already declined in this period from the Devonian acmic prominence. At length only two species were left in Bolivia in the early Permian period and Bolivicrania shows high specialization. Finally it is a remarkable fact that there is no distinct evidence indicating the relationship of the South America trilobites to the Arctic fauna except for Baldis and Blasco's Monorakidae ? gen. inlet. from the middle-upper Ordovician, Prov. Mendoza. However, as pointed out by the senior author with Tamura (1983), the Arcto-Pacific pelecypod family, the Minetrigoniidae, has reached as far as Peru in the late Triassic period.
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Dalmanitacea Vogdes, 1890 in the Devonian of Bolivia. Vest. Ust. ust. Geol., 43, 93- 101, 5 pls. Doumani, G. A. et al. (1965) : Lower Devonian Fauna of the Horlick Formation, Ohio Range, Antarctica. Geology and Palaeontology of the Antarctica (ed. Hadley, J. B.). Publ. Am. Geophys. Union., pp. 241-274, 18 pls. Eldridge, N., and Branisa, L. (1980) : Calmoniid Trilobites of the Lower Devonian Sacphiocoella Zone of Bolivia with Remarks on Related Species. Bull. Am. Mus. Nat. Hist., 165, Art. 2, 289 pp. Kegel, W. (1951) : S©bre alguns trilobites carbonif eros do Piaui e do Amazonas. Dep. Nac. Prod. Min. Div. Geol. Min. Bol., 135, 7-38, pl. 1. Kobayashi, T., and Hamada, T. (1977) : Devonian Trilobites of Japan in comparison with Asian, Pacific and other Faunas. Palaeont. Soc. Japan, Sp. Pap., no. 20, 202 pp., 13 pls. (1980) : Carboniferous Trilobites of Japan etc. ibid., no. 23, 132 pp., 22 pls. (1984) : Permian Trilobites of Japan etc. ibid., no. 26, 92 pp., 14 pls. -- (1986) : A new Permian genus of Trilobite from Bolivia . Proc. Japan Acad., 62B, 181-183. Kobayashi, T., and Tamura, M. (1983) : The Arcto-Pacific Realm and the Trigoniidae in the Triassic Period. ibid., 59B, 207-210. Kozlowski, R. (1923) : Faune devonnienne de Bolivie. Ann. Paleont., 12, 133-192. Suarez Soruco, R. (1971) : Tarijactonoides jarcasensis. n, gen. n, sp. del Devonico In- ferior de Tarija. Geol. Bolivia, Publ. Gol. Bol., no. 15, pp. 53-56, pl. 1. Wolfart, R. (1967) : Die Trilobiten aus dem Devon Bolivien and Ihre Bedeutung fur Stratigraphie and Tiergeographie. Beih. Geol. Jahrb., 74, 5-201.