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12. on the Redlichiacea (Trilobita) and the Redlichian Province

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12. on the Redlichiacea (Trilobita) and the Redlichian Province No. 2] Proc. Japan Acad., 63, Ser. B (1987) 43 12. On the Redlichiacea (Trilobita) and the Redlichian Province By Teiichi KOBAYASHI, M. J. A. (Communicated Feb. 12, 1987) Of the Redlichian Province Grabau was the first to illustrate a marine in gression from the Bay of Bengal into China and North India in his "Stratigraphy of China" (1924) . Prior to it Walcott (1913) placed Olenellus ( ?) f orresti of Australia in Redlichia and later King (1930) reported Redlichia chinensis and R. no bilis from Persia (Iran) . In North Asia the genus was found in Trans- baikalia, Tuwa, Kuznetsk and Usolka basin of the Siberian platform (Repina, 1966) . Now its distribution is extended to Mauritania, in North Africa and Antarctica (Poulsen, 1960 ; Palmer and Gatehouse, 1972) . Because Redlichias and Olenellids were found together in Morocco (Hupe, 1953), I have classified the early Cambrian biogeography into the Olenellian, Redlichian and intermediate provinces where both kinds of trilobites are coexistent in the last (1972) . The Redlichian province is here defined by the Redlichiacea, instead of Redlichia, as discussed hereafter in detail. Since Neoredlichia Saito, 1936 has been instituted, Redlichops R. et E. Richter, 1940, Wutingaspis Kobayashi, 1944 and other genera were successively added to the Redlichiidae Poulsen, 1927, and the Doleroleninae Kobayashi, 1951 was followed by some new families and subfamilies. Then Chang (1966) com- bined them in the Redlichiacea. In its emended classification by Chang and other Chinese palaeontologists (1980) the Redlichiidae comprises the following five subfamilies and many genera written behind them. Redliehiinae: Redlichia (Conoredlichia, Latiredliehia, Pteroredlichia) Syndianella, ? Dongshania Neoredlichiinae: Neoredlichia, Leptoredlichia Pararedliehiinae : Eoredlichia (Pararedliehia), Pachyredlichia, ? Redlichops, Ning- kiangaspis Wutingaspiinae : Wutingaspis, Chaoaspis, Kuangyangia (Sapushania), ? Keping- aspis, Chengjiangaspis Metaredlichiinae: Metaredlichia, Metaredlichioides, Zhenbaspis, (Zhenxiongaspis), Jingyangia, Maopingaspis, Pseudoredliehia, Bornemannaspis, Iglesiella, Brevired lichia, ? Sardoredlichia. Among these 25 genera Redlichops is indigenous to Jordan and Bornemanna- spis, Inglesiella and Sardoredlichia are all Rasetti's from Sardinia, Italy, but the remainder is all known from China. According to Chang and others the superfamily Redlichiacea comprises twelve families beside Redlichiidae. The Doreroleninae which I proposed for Dolerolenus in Sardinia contains Malungia in the Doleroleninae and a Chinese subfamily, Paramalungiinae Ihang et Lin, 1980 was added. The Yinitidae Hupe, 1953 with the Drepanopyginae Lu, 1961, the Mayiellidae Chang, 1960 and Kuei- chouiidae Lu, 1965 are three Chinese families. The Gigantopygidae and Despu- jolsiidae are two families in Morocco. The Saukiandidae has been a family of 44 T. KOBAYASHI [Vol. 63(B), Spain and Morocco, but recently the Yiliangellinae Zhang et Lin, 1980 was added to the family from China. The Menneraspidae Pokrovskaya, 1959, Redlichinidae Zhang et Lin, 1980 and the Chengkouaspidae Zhang et Lin, 1980 consist nearly all of Siberian genera except for Chengkouaspis Zhang et Lin, 1980. The Abadiellidae Hupe, 1953 originally erected for Abadiella of Morocco contains Iberian Lunolenus, Siberian Sibiraspis and four Chinese genera, i.e. Parabadiella Chang, 1966, Guangyuanaspis Chang et Chien, 1974, Malongocephalus Zhang et Lin, 1980 and Shaanxia Zhang et Lin, 1980. Finally, the Anadoxididae Nicosia et Rasetti, 1970 comprises six genera including two of doubtful references. Among them Fumingaspis Zhang et Lin, 1980 and Hongshiyanaspis Zhang et Lin, 1980 are two Chinese genera referable to the family. Thus it is quite evident that the Redlichiacea has flourished most in China and, precisely speaking, in the Yangtze basin. This is because Redlichia is a sole genus wide spread in the Hwangho basin, although there are two uncommon genera, Redlichaspis in Middle Cambrian of Shantung and Neoredlichia in North Korea. The latter occurs in N. nakamurai zone between the Redlichia coreanica and R. saitoi zones of the upper Redlichia shale beds near Phyongyang (1976). It is noted that Kepingaspis kepinensis Chang, 1965 is a monotypic species in west Sinkiang. Another region where the Redlichiacea has thrived is the Sayan-Lena region extending as far as the Kuznetsk basin through Transbaikalia. According to Suvorova (1960, 1961), Repina (1964, 1965, 1966), Pokrovskaya and Zadoroshnaya (1976) and Repina and Romanenko (1978), the superf amily is represented by the following families and genera. Redlichiidae : Astenaspis, Redlichia, Redlichina, Iolga Neoredlichiidae: Belliceps, Bigotinops, Bulaiaspis, Eleganellus, Inella, Nellina, Pseudoresserops, Resserops, Tereehtaspis, Tungusella 1VIetadoxididae : Metadoxides, Minusella, Paratungsella Dolerolenidae: Sajanaspis, Sibiriaspis, Tannuolaspis. It was in 1942 that I have pointed out an extensive marine transgression of the early Cambrian period into Australia in this journal. Subsequently the wide distribution of Redlichia in this continent was summarized by Opik (1957). Then Emuella and Balcoracania were erected for two indigenous redlichioids in South Australia and the Emuehlidae was proposed in the Redlichiina by Pocock (1970). Now it is proven that the Redlichian seas extended from the Adelaidian trough to the Transantarctic Mountains where Australaspis of the Neoredlichiidae indicates the lowest trilobite horizon. Redlichia sp. is contained in the Chorbu- sulina wikesi faunule, the next younger horizon (Palmer and Gatehouse, 1972). The Peri-Gondwana Redlichian seas can be plotted on the Eur-Asiatic side from Yunnan to Iran through the Himalayas, the Salt Range and Zagros Moun- tains (Schindewolf and Seilacher, 1955, Wolfart and Kurten, 1974) and further into the Mediterranean region. In the Dead Sea area R. and E. Richter (1941) described Redlichia (Redlichops) blanckenhorni which is now located in the Pararedlichiinae and the Cambrian sequence there is correlated to the Lower and Middle Cambrian of Morocco later mentioned (Parnes, 1971). In Sardinia, Italy Inglesiella ichuense occurs in the lower or Malope member and Sardored- lichia praespinosa, S. catinata and Nebidella limbata in the upper or Punta Menna member of the Nebia formation in addition to Bornemannaspis solitaria No. 2] Redli.chiacea, Redlichian Province 45 and Anadoxides armatus whose exact horizon is undetermined (Rasetti, 1972). In South France Jago described Galloredlichia noiri and Grandolenus midi respectively of the Pararedlichiidae and Dolerolenidae from the Alterneance greso-calcaires in the southern part of Montagne Noire. Their age is considered early Cambrian or the early Atdabanian of the Siberian platform (Courtessole et Jago, 1980) . In Spain some species of Perrector, Realaspis and Saukianda are described besides Redlichia sp. nov. (Sdzuy, 1981) and the Kjerulfia (Anda- lusiana) horizon is intercalated between the Saukianda horizon above and the Paleolenus-Lusatiops and the Dolerolenus-Lunol enus horizons below in the Lower Cambrian sequence (Lotze, 1961; Liiian and Sdzuy, 1978) . In Portugal the Callavia fauna of Vila Boim (Teixiera, 1952) is known but no redlichioid has been uncovered. In Morocco Hupe (1952) distinguished eight Lower Cambrian trilobite zones and found Pararedlichia and Neoredlichia respectively in the Fallotaspis tazem- mourtensis zone at the lowest and the Daguinaspis-Resserops zone i.e. the third zone counted from bottom. Subsequently Sdzuy (1978) discovered Eo f allotaspis, Heptina and Lemdadella below the Fallotaspis zone. The second genus resembles Minussella and the third Pararedlichia, Bigotia and Elegantellus in one or other aspect. Still later the Pro f o,llotaspis yakutensis zone and Fallotaspis zone are found respectively in the lowest and the next younger zone in the Atdabanian series in the Siberian platform (Rozanov and Sokolov, 1984). The Redlichian and Olenellian trilobites are coexistent in Morocco. Western Mongolia is another area where occur Eleganellus, Metadoxides, Minussella, Pseudoresserops, Fallotaspis, Fallotaspidella and Bulaiaspis. These areas are, however, two small contact areas of trilobites in the two kinds and they are widely isolated from each other. Because they are insufficient to constitute an independent biological province, the intermediate province is found to be an inadequate term. Furthermore it is noteworthy that such an area appears absent on the Pacific side (1986). On the basis of the present knowledge on the Redlichian province it may be divisible into seven subprovinces with reference to endemic genera. They are the Lena-Sayan subprovince (1) of North Asia, the Hwangho and Yangtze subprovinces (2-3) in Eastern Asia and the east Mediterranean, Zagros- Himalayan, Australian and Antarctic subprovinces (4-7) in the peri-Gondwana belt (1976) among which the superf amily has most flourished in the Yangtze subprovince near the centre. There the Lower Cambrian formation is divided into the Longwangmiao, Changlangpuan, Qionzhusian and Meishcunian stages in descending order (Xiang et al. 1981) where the last is the pre-trilobite stage pene-contemporaneous with the Tommotian in Siberia (Sokolov and Zhuravleva, 1983). The succeeding three stages are profused with the Redlichiaceae and the top stage with Redlichia s. str. Therefore the Redlichian province above dis- cussed was a biological province in the mediaeval and late Lower Cambrian ages. References*) Chang Tai-Yung
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