TRIASSIC FISHES FROM THE CASSANGE DEPRESSION (R. P. DE ANGOLA) MIGUEL TELLES ANTUNES * JOHN GRAHAM MAISEY U MANUEL MONTEIRO MARQUES u* BOBB SCHAEFFER U KEITH STEWART THOMSON uu General Coordinator M. T. ANTUNES Paleontology Coordinator B. SCHAEFFER .. Centro de Estratigrafia e Paleobiologia da Universidade Nova de Lisboa (INIC), Quinta da Torre, 2825 Monte da Caparica, Portugal . .... Department of Vertebrate Paleontology, The American Museum of Natural History, New York 10024, N. Y., U.S.A. ...... Centro de Estudos de Pedologia, Instituto de Investiga~iio Cienti­ fica Tropical, Tapada da Ajuda, 1300 Lisboa, Portugal . ........ The Academy of Natural Sciences, Nineteenth and the Parkway, Philadelphia, Pa 19103, U. S. A. Nfunero pp. 1-64 Ciencias da Terra (UNL) Lisboa 1990 Especial figs. 17, 11 pI. 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 TABLE OF CONTENTS Page ABSTRACT / KEY-WORDS 9 RESUMO/PALAVRAS-CHAVE 9 INTRODUCTION, by M. T. ANTUNES 11 1. HI~TORY OF DISCOVERY AND STUDY, by M. T. ANTUNES 11 n. GEOLOGIC OCCURRENCE, by M. M. MARQUES 13 H.l - The «Baixa do Cassange» 13 H.2 - The «Karroo Sysrem» in the «Baixa do Cassange» 15 Ill. FISHES FROM THE «BAIXA DO CASSANGE» 15 Ill.l - Introduction 15 Ill.2 - Systematics 16 III.2.1 - Selachii, by ]. G. MAISEY 16 Hybodontiformes Genus Lissodus 16 Lissodus cassangensis 16 III.2.2 - Osteichthyes, by B. SCHAEFFER 20 "Lower Actinopterygii" Genus Marquesia, new genus 20 Marquesia moutai 21 Genus Perleidus 23 Perleidus lutoensis 23 Perleidus lehmani, new species 25 Neopterygii Genus Angolaichthys 26 Angolaichthys lerichei 26 HI.2.3 - Sarcopterygii/Dipnoi, by K. S. THOMSON 29 Genus Microceratodus 29 Microceratodus angolensis 30 IV. SYNTHESIS AND DISCUSSION, by M. T. ANTUNES and B. SCHAEFFER 33 IV. 1 - Geological framing and the ichthyological fauna as a whole 33 IV.2 - Age 33 IV.3 - Paleoecology 34 IV.4 - Paleogeographical setting 35 SYNOPTICAL TABLE 35 BIBLIOGRAPHY 37 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 RESUMO /PALAVRAS-CHAVE ABSTRACT / KEY-WORDS Palvras-chave.' Peixes - Tritisico - Baixa do Cassange - Angola. Key-words.' Fishes - Triassic - Baixa do Cassange - Angola. A seguir a urn capitulo acerca da historia dos trabalhos de campo e ulteriores investigac;oes sobre a estratigrafia e a paleontologia da Serie de Following an historical summary of the field invesrigations and later Cassange, no Norte de Angola (e, em menor grau, unidades correlarivas da research on the srratigraphy and paleontology of the Cassange series in Lunda), e descrita a sucessao estrarigrafica observada na Baixa do Cassange Northern Angola (and to a lesser extent of correlated units from Lunda corn base, principalmente, em observac;oes de campo e em publicac;oes de F. Province, Eastern Angola), the srratigraphic succession at the Baixa do Mouta e M. M. Marques. Cassange is reviewed mainly on the basis of field observations and published A associaC;ao de peixes proveniente de dois niveis das "Camadas corn peixes", que constituem a parte inferior da serie de Cassange, estudada por conclusions of F. Mouta and M. M. Marques. C. Teixeira apenas quanro ao nivel principal (0 mais antigo), foi objecto de The fish assemblage from two levels in the "Beds with fishes" that nova descric;ao e de amilise critica. Inclui urn genera de sehiceo hibodon­ comprise the lower part of the Cassange series, formerly studied by roide de agua doce, LissodllJ. conhecido igualmente na Zona de Cynognathus Teixeira, have been critically redescribed. This includes (1) a fteshwater (Triasico inferior) da serie de Beauforr, da Africa do Sul; urn novo genero hybodont shark now assigned to the genus Lissodlls. also known from the de "paleoniscoide", Marqllesia (corn base nu~a especie antes atribuida ao Cynognathus Zone of the Beaufort series in South Africa; (2) a new genero Elonichthys) , agora considerado como urn canobiideo, gtupO cuja "paleoniscoid", Marqllesia (previously assigned to Elonichthys), now regarded historia decorre aparentemente entre 0 Carbonifero e 0 Ttiasico; duas as a canobiid, a group with an apparent history extending from the especies, uma das quais nova, do genero Perleidm. 0 qual tern vasta Carboniferous ro the Triassic; (3) two species, one new, of the genus repartic;ao em depositos marinhos do Triasico inferior, embora ocorra em Perleie/m which has otherwise an extensive distribution in lower Triassic outros, nao marinhos, da Baixa do Cassange e da Lunda; 0 neopterigio, marine sediments, although it occurs in the nonmarine ones at the Baixa generalizado, Angolaichthys. so conhecido na Baixa do Cassange e na Lunda, do Cassange and Lunda; (4) a generalized neopterygian Angolaichthys. which unica forma representada nos xistos argilosos friaveis, esverdeados, de urn . is apparently unique to Baixa do Cassange and Lunda. It is the sole taxon nivel algo superior ao principal da Baixa do Cassange; enfim, urn genero, in the somewhat higher, friable greenish shales level at Baixa do Cassange; ainda desconhecido noutras regioes, de dipnoico, Microceratodlls. que nao (5) an apparently distinct lungfish Microceratodm. which does not show a evidencia qualquer parentesco proximo, demonstravel, relarivamente aos demonstrably close relationship ro other Triassic ceratodonrids. The mosr demais ceratodontideos do Triasico. Os taxa mais frequentes sao Marqllesia, common of these taxa are Marqllesia. Perleidlls IlItoensis and Angolaichthys. Per/eidm IlItoensis e Ango/aichthys.' os restantes sao raros, sendo conhecidos All other taxa ate very scarce and are only known from the first localiry apenas na primeira localidade explorada (colheita de F. Mouta, 1930). No concernente cronologia das "Camadas corn peixes" que constituem exploited by Mouta (earlier 1930 collecrion). a a parte inferior da Serie de Cassange, a fauna icriologica indica claramente In regard to the chronology of the Cassange series, the evidence of the idade do Triasico e, possivelmente, do Triasico inferior. fishes points clearly rowards a Triassic and possibly early Triassic age for Dados de natureza litologica e paleontologica sugerem que 0 ambiente the "Beds with fishes". The lithic and paleontological evidence suggests onde decorreu a fossilizac;w corresponde a urn lago poueo profundo, de agua that the environment of preservation was a shallow, widely fluctuaring doce, corn margens sujeitas a fortes deslocamentos sazonais. 0 clima era marginal freshwater lake area with shifring shorelines. The climate was presumivelmente caracterizado pela alterniincia de estac;oes humidas e secas; presumably characterized by alternating wet and dry seasons, with the os peixes morriam no decurso das fases de seca e fossilizavam, ao serem fishes dying during the dry phases, subsequently covered by sediment and cobertos por sedimentos. so being preserved. As vias de dispersao que dizem respeito a fauna da Serie de Cassange sw The dispersal routes involving the Cassange series organisms remain desconhecidas, 0 que tambem se verifica na maioria dos casos de associac;oes unknown, as do most freshwater assemblages that inhabited the continent de organismos dulc;aquicolas que habitaram 0 continente d. Pangea em fins of Pangea during the late Paleozoic and early Triassic times. da Era Paleozoica e nos primeiras tempos do Triasico. 9 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 INTRODUCTION, by M. T. ANTUNES I - HISTORY OF DISCOVERY AND STUDY, by M. T. ANTUNES This account is based on events that began more than half a century ago when the Portuguese engineer Fernando The discovery in 1930 of well preserved fishes in red, O. V. Mouta discovered beautifully preserved fossil fishes thin-layered rocks along the banks of the Lutoa (formerly in the Baixa do Cassange (Cassange depression) in Angola. written Lutoe) River in the Baixa do Cassange, Angola, was This discovery proved to be one of the most important made by Fernado Mouta (1890-1970). A mining engineer, paleontological finds in Angola, and an outstanding one he was appointed in 1922 to the staff of the Missao Geol6- in the Gondwanaland deposits of Africa. gica de Angola (1922-1926). Mouta was subsequently one The study of the fossil fishes was offered first to the of the main contributors to our knowledge of Angolan paleoichthyologist Maurice Leriche. However he produced geology. The Missao Geol6gica de Angola was superseded only two short papers on this subject. The main contribu­ in 1926 by the Servic;o da Carta Geol6gica de Angola, tions came from Carlos Teixeira, Professor at the University in which Mouta continued until 1931. His name remains of Lisbon, who played an important role in describing the linked to an important paleontological discovery in Africa, fossils of Baixa do Cassange. He also exercised an enormous a well-preserved fish fauna of Triassic age. Futthermore, influence on geological studies in Portugal and its former these Triassic fishes are of critical interest for the regional colonies. By his continuing activity up to his death in chronostratigraphy. Unfortunately Mouta's field work had to 1982, he deserves a special recognition. However, his papers be discontinued. He was appointed to other tasks, namely did not provide a comprehensive, detailed account of the Director of the Servic;os de Minas de Angola (1934-1938) paleoichthyological fauna from the Baixa do Cassange. and Mayor of Luanda (1935-1940).