Transactions and Proceedings of the Palaeontological Society of Japan New Series No. 88 Palaeontological Society of Japan December 20, 1972 ---------------------·-· Editor: Takashi HAMADA Associate Editor: Yasuhide IWASAKI Officers for 1971 - 1972 President : Tokio SHIKAMA Councillors(* Executives): Kiyoshi ASAND*, Kiyotaka CHINZEI*, Takashi HAMADA*, Tetsuro HANAI*, Kotara HAT AI, ltaru HAY AMI, Koichiro lCHIKA WA, Taro KANAYA, Kametoshi KANMERA, Tamio KOTAKA, Tatsuro MATSUMOTO*, Hiroshi OZAKI*, Tokio SHIKAMA*, Fuyuji TAKA!*, Yokichi TAKAYANAGI Secretaries: Wataru HASHIMOTO, Saburo KANNO Executive Committee General Affairs: Tetsuro HANAI, Naoaki AOKI Membership : Kiyotaka CHINZEI, Toshio KOIKE Finance: Fuyuji T AKAI, Hisayoshi lGO Planning: Hiroshi OZAKI, Kazuo AsAMA Publications Transactions: Takashi HAMADA, Yasuhide IWASAKI Special Papers: Tatsuro MATSUMOTO, Tomowo OZAWA '' Fossils" : Kiyoshi AsANO, Toshiaki TAKAYAMA All communications relating to this journal should be addressed to the PALAEONTOLOGICAL SOCIETY OF JAPAN c/o Business Center for Academic Societies, Japan Yayoi 2-4-16, Bunkyo-ku, Tokyo 113, Japan. Sole agent: University of Tokyo Press, Hongo, Tokyo Trans. Proc. Palaecint. Soc. Japan, N. S., No. 88, pp. 447-457, pl. 54, December 20, 1972 607. UPPER TRIASSIC CEPHALOPODS FROM THE TANOURA DISTRICT, KUMAMOTO PREFECTURE, JAPAN* T AKESHI ISHIBASHI Department of Geology, Faculty of Science, Kyushu University Jm;fs:~llliinit!!JrRO)J:ll!I.:::.~*~~.:Em = lm**~HI\. mim!i!Wll::~:tn-t7.> .=:.t~l±liilll! :t,;.tCJ'!liili"'JI.t IJ imllit...t-:. \!J:.lEID~#it-tt..~ifi*· ;;t-l,~W nt. ~:Pii stm~~ll'.t.. t-:., ? ~~1i 1 f!H1¥rf<1l't'<l:>oo .:.tt,~O)iji.lEmri'l'ft~'t'li<I:>.Oil:, 8*0).:::.:\ilf..t 1HJJII.> "Cffl'.!i' <Ht.7.> ~lim t <!:> 1J, i!ti.lEfflitJ#JtlfO)lVf~i;:l;tiJtli:"t' <1; .o. .:.tt. 'f "t':i':l::::. =tHHt:ril: t c-? ~~~~ttn:~n.: Mt. -c~.o,t~n:. .:. .:. "t'iii.lEmft1i~:. J: .o IF.fttl::::. ··:w-cfi=f~ t:.. llliitl/1 O)J~t'lKiiHil-~7:--'l::i~-t.ORfi'mM:~mmit...t=, :Pt~ *:1 upper members. The lower member Introduction and aclmowledgments yields cephalopod fossils, which were The cephalopods described in this ar· collected from the following localities ticle were collected from the Upper denoted by numbers** : Triassic Tanoura (TAMURA et a!., 1958) · Loc. 85 Buchites kumamotoensis n. sp. and Takagochi (ORITA, 1962) Formations Loc. 43 Phormedites sp. distributing in the Tanoura district, Loc. 46 Rhacophyllites sp. Kumamoto Prefecture. TAMURA (1959) Loc. 25 Buchites kumamotoensis n. sp. and ORITA (1962) studied the stratigra· Arcestes sp. cf. A. (Proarcestes) phy and molluscan fossils of the Tano­ ausseeanus (HAUER) ura Formation. Almost all the speci­ Ussuritidae or Discophyllitidae mens used in this study were collected gen. et sp. indet. by them, except for a few which were Loc. 44 Holconautilus sp. collected by myself. ORITA (1962) listed several ammonoids The Takagochi Formation is about which were preliminarily examined by 400 m in thickness (ORITA, op. cit.), and MATSUMOTO. Based on the bivalves and yields molluscan fossils through out the ammonoids, the Tanoura Formation was formation. Ammonoid was found in its referred to as the Carnian and the Ta· middle part (Joe. 52 and 55), and is re­ kagochi Formation as the Carnian to presented by only a single species, Pia­ Norian in geologic age (TAMURA 1959; cites sp. aff. P. oxyphyllus (MOJSISOVICS). 0RITA. 1962). This ammonite is associated with Pleu­ According to ORITA (op. cit.), the Ta­ romysidia kanmerai TAMURA, Paleoneil~ noura Formation is about 250m in thick· iwaiensis lCHIKA wA, Halobia sp ., etc .. ness and is divided into the lower and Pleuromysidia kanmerai TAMURA and * Received May 25, 1972; read Jan. 23, •• The numbers of locality correspond with 1972 .at Chiba. those of 0RITI. (1962). 447 448 Takeski ISHIBASHI 0 3KM Text-fig. 1. Location of samples collected. Halobia (?) sp. occur in the lower part of Takagochi Formation is suggestive (loc. 54), whereas 1Honotis (Entomonotis) of the Norian, conservatively the Carno­ sp. cf. M. (E.) typica (KIPARISOVA) is Norian age. known from the upper part (toe. 56). The cephalopod fauna of the present On the basis of the molluscan fossils study generally resembles that of Sara­ ORITA (op. cit.) concluded that the upper gai Group of Northeast Japan which in­ part was early Norian, and the middle cludes species of Placites, Rhacophyllites and lower parts were Carnian in age. and Arcestes (SHIMIZU and MABUCHI, NAKAZAWA (1964b) also considered that 1932; NAKAZAWA, 1964a). ISHIBASHI the middle horizon (locs. 52, 55) of Taka­ (1970) reported numerous Carnian am­ gochi Formation was referable to the monites from the Okinawa-jima, but Late Carnian. little genera are common between the I investigated the cephalopod fossils Tanoura district and the Okinawa-jima, collected from the Tanoura and Taka­ except for Arcestes. Two species of gochi Formations, and identified one Buchites and Phormedites to be described nautiloid species and five ammonoid spe­ in this article are known from the Ja· cies, of Which one is new. On the basis panese Islands for the first time. of this ammonoid faunule the lower I wish to express my sincere thanks member of the Tanoura Formation is to Professor Tatsuro MATSUMOTO of correlated with the L~te Carnian. Ac­ Kyushu University for his arrangements cordingly the upper member probably of the material. criticisms and reading extends to the Early Norian. Placites of the manuscript, and to Professor sp. aff. oxyphyllus from the middle part Ryuzo TORIY AMA of the same university 607. Triassic cephalopods from Tanoum 449 "'for kindly reading preliminary draft and Buchites kwrlamotoensis ISHIBASHI, -encouragement. Thanks are also due to sp. nov . Professor Minoru TAMURA of Kumamo· ·to University for the offer of his am- Pl. 54, Figs'. 1-9, 10? and 11? monoid collections. I am obliged to Miss 1962. Helictites? sp., ORITA, Sci. Rept., Fac. :Seiko 1-IAYAKAWA for typewriting the Sci., Kyushu Univ., Vol. 6, No. 1, p. 4, .manuscript. listed . Repository.-All specimens illustrated ··in this article are deposited· in the De­ Material.-The holotype (GK. F 458) _partment of Geology, Kyushu University and some of paratypes (GK. F 459-462), ·with the registered number using a collected by Dr. TAMURA from the Umi­ :symbol of GK. F. noura area (loc. 25), Kumamoto · Prefec· ture. Two others (GK. F 374, 375) listed already as Helictites ? sp. collected by Systematic paleontology Mr. ORITA and the rest (GK. F 463-466) by myself. Class Cephalopoda CUVIER, 1797 Description.-Shell considerably invo­ :Subciass Ammonoidea AGASSIZ, 1847 lute and compressed, increasing gra­ dually its height. Whorl embracing Order Ceratitida HYATT, 1884 about a half or one-third of the inner whorl; umbilicus narrow and moderately Superfamily Clydonitaceae deep; ribs strong, rounded, flexiradiate MOJSISOV!CS, 1879 on the flank and projected on the ven· Family Buchitidae HYATT, 1900 trolateral part, with irregularly inter· calated secondaries, without crossing Genus Buchites MOJSISOVICS, 1893 over the venter ; venter round, smooth where ribs gradually disappear ; suture Type-species.-Ceratites (Buchites) al· ceratitic. with serrated lobes. cdrovandii MOJSISOVICS, 1893. Remarks.-The present species is some· Remarks.-The genus Buchites was what similar to Helictites beneckei re· ·originally established by MOJSrsovrcs ported by MOJSISOvrcs (1893) from the •(1893) as one of the subgenera of Cera· Alps in lateral view, but the ribs of the tites. The species belonging to Buchites latter cross straight over venter . are known only from the Carnian to The present new species rather resem· Norian of the Tethys region, such as bles Buchites aldrovandii {MOJSISOV!CS) ·the Alps, Greece, Sicily, Himalayas and from the Alps but the whorl of the ·Timor. Buchites has flexuous ribs which latter is more evolute than that of the :are projected at the ventrolateral shoul· former. -der and gradually disappear on the The other known species from the ·rounded venter but occasionally cross Alps and Himalayas are characterized by ·over it in the last whorl of a mature the appearance of the flexuous short ·specimen. Whorls are moderately in­ lateral ribs at the ventrolateral area. B. volute, increasing its height at a mo­ kumamotoensis has bifurcating ribs some ··derate rate. Ribs are distinct and in· of ~hich diverge from the main ribs at ·.tercalated with the short ones. or near the umbilical shoulder, and its suture-line has the serrated accessary 450 '71alcesh'i [SffiBASfll lobes. The suture:iine of B. kumamo­ CKAS (1928) from Timor. On the ·other toensis is rather· similar to B. modestus hand, the Norian one, Ph. juvavicus was~ (BUCH) .from the Alps, but the latter is described . by MOJSisovrcs (1893) from, evidently different in that the ribs sli· the Alps and by PAKUCKAS (1928) from .ghtly cross over the venter and has a Timor. Ph. fascia/us was reported bY' ·broad U:rhbilicus. B. emersoni and B. cf. MOJSISOVICS (1893), DIENER (1906) ana hilaris described by DIENER (1906) have PAKUCKAS (1928) from the Alps, Hima-­ evolute whorls and primitive sutures. layas and Timor, respectively. Buchites heteroplichus reported by Based on the original descriptions of' GEMMELLARO (1904) is very similar to these species, species of Phormedites are" the present new species with respects divided into the following two groups:. to only the whoi! volution. but is clif· 1. The group of Ph. schopeni-Ph. ferent from the latter in the characteris­ juvavicus tics of ribs, whorl size, venter, etc. It · Shell is consideral::lly involute with. is resonable to establish a new species fine, prorsiradiate ribs. The ribs cross .. in the genus Buchites for the present over the venter. The venter is round .. form. The type-species, Ph. juvavicus, is about. Occurrence.-Locs. 25 and 85. With Ar­ 28 mm in diameter. cestes sp. cf. A. (Proarcestes) ausseeanus 2. The group of Ph. pygmaeus-Ph. (HAUER) and Halobia ? sp. (Loc. 25). ani:! fasciatus Pleuromysidia kanmerai TAMURA (Loc.