The Conodont Biostratigraphy of the Black Prince Limestone (Pennsylvanian) of Southeastern Arizona
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Authors Barrie, Kathleen Ann
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Link to Item http://hdl.handle.net/10150/240113 THE CON ODONT BIOSTRATIGRAPHYOF THE
BLACK PRINCE LIMESTONE(PENNSYLVANIAN)
OF SOUTHEASTERN ARIZONA
by Kathleen Ann Barrie
A Thesis Submitted to the Faculty of the
DEPARTMENT OF GE OS CIEN CE S In Partial Fulfillment of the Requirements For the Degree of
MASTER OF SCIENCE In the Graduate College
THE UNIVERSITY OF ARIZONA
1975 STATEMENT BY AUTHOR
This thesis has been submitted in partial fulfillment of re- quirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this thesis are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his judg- ment the proposed use of the material is in the interests of scholar- ship. In all other instances, however, permission must be obtained from the author.
SIGNED:
APPROVAL BY THESIS DIRECTOR This thesis has been approved on the date shown below:
27(?7s- DIETMAR SCHULZACHER ' Date Assistant Professor of Geosciences ACKNOWLEDGMENTS
I would like to thank the many people who helped me in the completion of my thesis. Special thanks are due to Dr. Dietmar Schumacher, thesis director, who gave me guidance and help in every phase of this study. Thanks are also due to the other members of my thesis committee, Drs. Donald L. Bryant and Joseph F. Schreiber, Jr. Fellow graduate students helped in many ways and I would like to thank them, especially William C. Sulkoske. Dr. Richard Lane, Amoco Research Center, Tulsa, Oklahoma, helped in the identification of some of the conodonts and in the interpretation of the biostratigraphy. Dr. David LeMone of the Department of Geology, University of Texas at El Paso helped in the identification of the carbonates.Thanks are due to Dr. Walter Roser, Department of Metallurgical Engineering,
University of Texas at El Paso,and Drs.Thomas Teska and Michael
Drake,Department of Planetary Sciences,The University of Arizona, who provided free instrument time and assistance in obtaining the scan- ning electron microscope photomicrographs. Some financial aid for this research was provided by the Max- well Short Scholarship. Encouragement and financial support were given by my parents, Mr. and Mrs. Ferdinand J. Barrie.
iii TABLE OF CONTENTS
Page
LIST OF ILLUSTRATIONS vi
ABSTRACT vii
INTRODUCTION 1
Methods 1 Location 2 Geology and Stratigraphy 4 Previous Work 7 Arizona Conodont Studies 7 Morrowan Conodont Biostratigraphy 7
BIOSTRATIGRAPHY OF THE BLACK PRINCE LIMESTONE 11
Neognathodus bassleri Zone 11 Idiognathodus sinuosis- Streptognathodus antee c ce ntricu s Zone 13 Idiognathoides convexus Zone 13 Spathognathodus coloradoensis -Neognathodus columbiensis Fauna 14 TEMPORAL RELATIONSHIPS WITHIN THE LOWER PENNSYLVANIAN OF SOUTHEASTERN ARIZONA 15
DEPOSITIONAL ENVIRON MENT 18
CONCLUSIONS 20
SYSTEMATIC PALEONTOLOGY 21
Genus Adetognathus Lane,1967 22 Adetognathus lautus (Gunnell),1933 22 Adetognathus spathus (Dunn),1966 24 Genus Idiognathodus Gunnell, 1931 25 Idiognathodus sinuosis Ellison & Graves, 1941 25 Genus Idiognathoide s Harris & Hollingsworth, 1933 26 Idiognathoides convexus (Ellison & Graves),1941 2 6 Idiognathoides noduliferus (Willson & Graves),1941... 27 Idiognathoides s inuatu s Harris & Hollingsworth, 1933 .. 28 Genus Neognathodus Dunn, 1970a 29 Neognathodus bassleri (Harris & Hollingsworth), 1933.. 29 Neognathodus columbiensis (Stibane),1967 30 iv V
TABLE OF CONTENTS -- Continued Page
Genus Rachistognathus Dunn, 1966 32 Rachistognathus muricatus (Dunn),1965 32 Genus Spathognathodus Branson & Mehl, 1941 33 Spathognathodus coloradoensis Murray & Chronic, 1965. 33 Spathognathodus minutus (Ellison),1941 34 Genus Streptognathodus Stauffer & Plummer, 1932 35 Streptognathodus anteeccentricus Dunn, 1966... 35 Streptognathodu s expansus Igo & Koike, 1964 36 Strepto nathodus suberectus Dunn, 1966 37 Genus A, sp. A 38
REFERENCES 40 LIST OF ILLUSTRATIONS Figure Page 1. Location map of measured sections of the Black Prince Limestone 3
2. Some late Paleozoic formations of southeastern Arizona. ... 5 3. Comparison of some Morrowan conodont zonations 9 4. Conodont zones and ranges of important conodonts in the Black Prince Limestone 12 5. Temporal relationships within the Lower Pennsylvanian of southeastern Arizona 16 6. Stratigraphic sections and distribution of conodonts in the Black Prince Limestone in pocket
7. Adetognathus,Idiognathodus,Idiognathoide s, Neognathodus 23
8. Neognathodus,Rachistognathus,Spathognathodus, Streptognathodus, Genus A 31
vi ABSTRACT
The Black Prince Limestone of southeastern Arizona has been assigned to the Morrowan on the basis of several long -ranging fossils. Since these were not especially diagnostic, the exact time represented by the Black Prince within the Morrowan was uncertain. To date the Black Prince more precisely, six sections were systematically sampled
for conodonts. The condonts found, especially Neognathodus bassleri,
Rachistognathus muricatus,Idiognathoides convexus,and Spatho-
qnathodus coloradoensis,indicate a middle Morrowan to early Derryan age for the Black Prince in the study area. Four conodont zones can be recognized: the Neognathodus
bassleri Zone,the Idiognathodus sinuosis.- Streptognathodus anteeccen-
tricus Zone,the Idiognathoide s convexes Zone,and the Spathognathodus
coloradoensis -Neognathodus columbiensis Zone.These zones compare favorably with the zonation previously established in the type Morrowan. This biostratigraphic evidence suggests that the hiatus between the Black Prince and Horquilla Limestones increases in magnitude from southeastern to south -central Arizona. The Black Prince represents a sequence of tidal flat and shallow
subtidal carbonate deposits. Mudstones and sparsely fossiliferous wackestones with low fossil diversity and abundance characterizethe tidal -flat facies. Grainstone s,packstones, and fossiliferous wacke- stones with high fossil diversity and abundance characterizethe shal- low subtidal facies. vii INTRODUCTION
This study was undertaken to determine more preciselythe age of the Black Prince Limestone. Conodonts were chosen for this study because they are relatively abundant throughout the formation.Another advantage in using conodonts is that there exists a highly refined cono- dont zonation for the Morrowan in the central and western United States. The conodont zones established in this study can then be compared to the standard zones in the rest of the country.
Fusulinids,which are used to date most of the Pennsylvanian and Permian formations in Arizona, cannot be used to date the Black Prince because their occurrence is rare in the formation. Those fu su linid s present are primitive and long ranging. There are also few diagnostic macrofossils in the Black Prince. In this study an attempt was also made to determine the length of the hiatus between the Black Prince and the overlying Horquilla and
Naco formations.This will help to clarify the stratigraphic relationships between the formations. Finally, an effort was made to determine what environmental controls, if any, there were on conodont distribution within the Black Prince.
Methods Six sections were measured using a Brunton compass and Jacob staff. Samples were collected from every bed. The sample size varied
1 2
from approximately 2 to 4 kg.At least 1 kg of each sample was dis- solved (at least partially) in 10 percent acetic acid. The dried residue was then separated in heavy liquid, tetrabromoethane , as described by
Collinson (1963).The heavy residue was then picked for conodonts. Rock descriptions were based on thin sections and polished hand specimens. Dunham`s (1962) classification was used for rock type. All photomicrographs were taken with Polaroid Type 55 P/N film using a scanning electron microscope.
Location For this study six sections of the Black Prince Limestone in southeastern and south -central Arizona were measured and sampled for
conodonts.These sections are indicated by number on the locationmap
(Fig. 1). 1.Superior: NE1/4SW1/4 sec. 36 and SE 1 /4NW1 /4 to SW1 /4
SE 1/4 sec. 36, T.1 S.,R. 12 E.,Superior quadrangle, Pinal County. 2.Ekiminzin Wash: NE 1 /4NE 1/4 sec. 36 to SW1/4SE1/4sec. 25, T. 5 S., R. 16 E., Saddle Mountain quadrangle, PinalCounty. 3.Johnny Lyon Hills: SE 1 /4SE 1/4 sec. 16 to SW1 /4sec. 15, T.
14 S.,R. 21 E.,Dragoon quadrangle, Cochise County. 4.Dry Canyon,VIihetsone Mountains: NW1 /4sec. 23 to NW1 /4
sec. 22, T.19 S., R. 19 E., Benson quadrangle,Cochise County. 3
N
.-/
i z \ PHOENIX I Drn o E J I ( h_ ` i _...11 i \ N I \ - o 2. I \z I i D SO 100 KM `o ___r I. L_. _ _ - I I \ i i ó ucsoN I o 1 3. L
L IIMMIMM,
A 5.
i BISBEE 1 0 6.o
Figure 1.Location map of measured sections of the Black Prince Limestone 4
5.Swisshelm Mountains: SE1/4SW1 /4 sec. 35, T. 19 S., R. 27
E.,Swisshelm Mountain quadrangle , Cochise County. 6.Naco Hills: SE1/4SW1/4 sec. 35 to SW1/4SW1 /4SE 1 /4SE 1/4
sec. 26, T. 23 S .,R. 23 E.,Bisbee quadrangle, Cochise County.
Geology and Stratigraj y Gilluly, Cooper, and Williams (19 54) named the Black Prince Limestone for exposures near the Black Prince mine in the Little Dragoon
Mountains.Because of metamorphism, the type section was measured at Gunnison Peak 4.5 miles to the southeast. Additional sections were mea- sured in the Johnny Lyon Hills and the Little Dragoon Mountains. The Black Prince was originally considered a member of the Escabrosa Limestone. It was raised to formation status because its fos- sils, especially Lithostrotionella and Linoproductus, areindicative of the Late Mississippian and Early Pennsylvanian, therefore making it in- termediate in age between the Escabrosa and Horquilla (Fig. 2). Nations (1963) studied the three sections described by Gilluly and others (1954) and a section in the Whetstone Mountains and made a more detailed examination of the fossils .He assigned a Morrowan age to the Black Prince on the basis of Millerella marblensis,Plectoqyra, and several corals,especially Chaetete s.The heads of Lithostrotionella described by Gilluly and others (1954) were interpreted by Nations to be reworked from the underlying Escabrosa. The Black Prince Limestone consists of a sequence of relatively weak and sometimes poorly exposed beds overlyingan erosional surface VI RGIL AN EARP FORMATION (part) DESMISSOURIAN MOINESIAN LIMESTONEHORQUILLA FORMATION NACO MoRROwANDERRYAN BLACK PRINCE LIMESTONE M ERCH AME ESTER! CIAN AN PARADISE FORMATION KINOSAGIAN DER HOOK IAN ESCABROSA LIMESTONE Figure 2. Some late Paleozoic formations of southeastern Arizona CI1 6 of low local relief on the Escabrosa and Redwall Limestones (Osagian and early Chesterian) and on the Paradise Formation (late Meramecian to
middle Chesterian).The base of the overlying Horquilla or Naco (middle to late Derryan) locally represents a reworked residual silty lateritic soil
resting on a Black Prince surface of some relief (Ross,1973).
In outcrop,the Black Prince is conspicuous because of the low ridge it forms between the cliff- forming Mississippian formations and
the resistant ridges of the overlying Pennsylvanian formations.The Black Prince is also recognized by the reddish clastic beds that com- monly occur at the upper and lower formational boundaries and by the
very light gray weathering limestone. Two members are usually recog-
nized in the Black Prince,a lower clastic member and an upper lime- stone member. The lower member is composed of red siltstone, maroonshale,
and a few thin beds of limestone.The reddish clastic beds at the base of this member vary greatly in thickness at different sections andmay be absent. According to Ross (1973, p. 891), theupper member is composed of light -gray limestone having calcarenitic beds, rich in echinodermal fragments and algal biscuits (principally Osagia),micritic limestone beds with many algal nodules and brecciated algal -mat bedding surfaces,and a few congomer- ates with intraformational and interformational limestone pebbles. Ross (197 3) extended the geographic limits of the BlackPrince to include areas where it had not been previously recognized,including outcrops in Pinal, Gila, Pima, and Cochise Counties, Arizona,and 7 Hidalgo County, New Mexico. In these areas the Black Prince had pre- viously been included as part of the E scabrosa , Horquilla, or Naco formations.
Previous Work
Arizona Conodont Studies Reid (1968) was the first to report conodonts from the Pennsyl- vanian of Arizona. He measured and described four sections of the Naco Formation in south -central Arizona. Three of these sections include strata now assigned to the Black Prince Limestone. Reid assigned a late Morrowan to Virgilian age to the Naco on the basis of conodonts and
fusulinids. Micklin (19 69) studied a Pennsylvanian- Permian section in the
northern Dragoon Mountains.He retrieved conodonts of Morrowan to Wolfcampain age from this section. Totten (1972) studied the conodont faunas from the Mississip-
pian and Pennsylvanian of the Naco Hills southwest of Bisbee.He re- ported Morrowan conodonts from the basal Pennsylvanian unit that Ross (1973) subsequently assigned to the Black Prince.
Morrowan Conodont Biostratigra by In the last decade a highly refined biostratigraphic zonation has been developed for the conodonts of the Morrowan in the United
States.Lane (19 67) proposed the first zonation for rocks of Morrowan age based on his studies of the type Morrowan in northwestern Arkansas. 8
This zonation along with those of Webster (1969) , Dunn(1970a, 1970b), and Lane and Straka (1974) is shown in Figure 3. Webster (19 69) pro- posed a Streptoqnathodus noduliferus-- Idiognathoides convexus Zone in southern Nevada for strata that he considered to be early or middle Mor- rowan. Dunn (1970a, 1970b) described several zones for the Chesterian of Nevada and Utah and the Morrowan of Nevada, Utah, and Oklahoma. Lane, Merrill, Straka, and Webster (1971) presented several zonations for North American Pennsylvanian conodont biostratigraphy. Areas included in this study were the southern midcontinent, the south - western United States,and the central Appalachians.In the study of the southern midcontinent Lane and Straka presented a revision of Lane's
(19 67) zonation.Lane and Straka (19 74) further refined the zonation pre- sented by them in the Lane,Merrill, Straka,and Webster (19 71) study.
Their zonation for the Lower Pennsylvanian follows,in ascending strati - graphic order. The lowest Morrowan zone, the Rachistognathus primus
Zone is defined by the range of that species.The Idiognathoides nodu- liferus Zone is characterized by the range of I. noduliferus above the last occurrence of R. primus and below the first occurrence of Neognathodus bassleri symmetricus.The N. bassleri symmetricus Zone is defined as the range of this species below the first occurrence of N. bassleri bass- leri.The N. bassleri bassleri Zone corresponds with the ranges of N. bassleri and Idiognathoides sulcatus parvus, below the firstappearance of the genera Idiognathodus and Streptognathodus.An Idiognathodus sinu- o s i s Zone is defined by the overlap in ranges of I. s inuo s i s with N. bass- leri bassleri.The Idiognathodus klapperi Zone is found in those rocks sY R D U s j s i ES CONODONT ZOVES LANE NE & L A N E VEBSTER I97O , N N, o,b . F D E Q' R Y çSp. color°doensisN. co/umbiensis(this report) /diognothoidesSTR AKA,1974 n. sp. 19 6 7 19 6 9 Ici. /d. hum. NEV. OKLA. /. convexus /. convexus /diognothoides `' sin. y JfT1A. spolhusS. par vus /d, k / o p p e r i SP/2. ^.N. middl e oy Lo,) /d. hum. .-nCL Z /d. - ._._ sinuos is oC a431cc '°h0J Id. sin. O< S, onteeccentricus Id. sinuosis , (ri S, exp.S. sub.
Four conodont zones are recognizable in this study. These zones are shown, along with the ranges of the diagnostic species ,in Figure 4. The correlations of these zones with other zonations in the United States is shown in Figure 3. The zones of the Black Prince Lime- stone will be discussed in ascending stratigraphic order.
N e ognathodu s bassleri Zone The limits of the N e oganthodu s bassleri Zone are defined by the range of N. bassleri to just below the first occurrence of either Idiognathodus s inuo s i s or Streptognathodus ante e cce ntricu s. Associated
species are Adetognathus lautus,A. spathus,Idiognathoides noduliferus,
I. sinuatus,Rachistognathus muricatus,and Spathognathodus minutus. This zone correlates, at least in part, with the N. bassleri symme tricu s and N. bassleri bassleri Zones of Lane and Straka (1974).
In my study the subspecies are not stratigraphically separable.The N. ba s s er l i Zone also corresponds with the lower Streptognathodus noduliferus- Idiognathoides convexus Zone of Webster (1969) and with the Declinognathodus noduliferus and N. bassleri Zones of Dunn (1970a,
1970b). This zone occurs in the Swisshelm Mountains, the Naco Hills, and the Whetstone Mountains.
11 ( hoR R0V1AN PENNSYLVANIAN _ (part r t p a r t) DERRYAN (part) S Y S T EMS E R I E S N. boss/er . S. on/eecce nJ`rr'cus Id. Mr' //ere/ /asinuosis -- /. convexus N.Sp. columbi colorodoenssp . ensis P C ONODONZONS T 5 O A.N.R. muricafus/outus b oss/eri , /.Sp.A. rninut us nospothus du/iferus /.=Az /diognothaides Adetognothus S./d.1. anteeccentricussinuotussi n u o s i s - N.=/d.=R.= /diognoNeognatho Rochistognothus thodu dus s Sp./.S. co/orodoensr's cs ubo n e v re exu c t us s Sp.: S.:Streptognothodus Spothognothodus Figure 4. Conodont zones and ranges of important conodonts in the Black Prince Limestone - s.N. co/umbiensisexponsus 13
Idioqnathodus s inuo sis -Streptognathodu s anteeccentricus Zone The limits of the Idioqnathodus sinuosis -Streptoqnathodus anteeccentricus Zone are defined by the first occurrenceof either of the name givers to below the first occurrenceof Idiognathoides convexus. Associated species are Adetognathus lautas , A. spathus,Idiognathoides
noduliferus,I. sinuatus,Spathognathodus minutus,Streptoqnathodus suberectus, and Genus A, sp. A. This zone correlates with the I. sinuosis Zone of Lane and Straka (1974) and possibly with part of their Idioqnathodus klapperiZone. The I. sinuosis -S. anteeccentricus Zone also correlates with thelower subzone of Webster's (1969) S. noduliferus --I. convexus Zone andwith all or part of Dunn's (1965) upper three zones. Lane and Straka(1974) correlated their I. sinuosis Zone with the basal part of the Marble Falls Limestone of Central Texas .Nations (1963) correlated the Marble Falls with the lower third of the Black Prince Limestone at the Johnny Lyon
Hills.That same unit at the Johnny Lyon Hills contains conodonts char- acteristic of the I. sinuosis-S. anteeccentricus Zone .This zone is found in all measured sections of my study.
Idiognathoides convexus Zone The Idiognathoides convexus Zone is defined by the range of I. convexus below the first occurrence of eitherSpathognathodus colorado-
ensis or Neognathodus columbiensis.Associated species are Adeto- qnathus lautu s, A. spathu s, Idioqnathodus sinuosis, Idiognathoides
noduliferus,I. sinuatus,Spathognathodus minutus,Streptognathodus
a nteeccentricus , S. suberectus, and Genus A, sp. A. 14
This zone correlates with the L. convexus Zone of Lane and Straka (1974) and possibly with part of the underlying I. klapperi Zone. The I. convexus Zone of the Black Prince also correlates with part of the middle subzone of Webster's S. noduliferus-I. convexus Zone and pos- sibly with part of Dunn's upper three zones.This zone occurs in the Johnny Lyon Hills, the Naco Hills, and the Swisshelm Mountains.
Spathognathodus coloradoensis-Neognathodus columbiensis Fauna The lower limit of the Spathognathodu s coloradoensis - Neognathodus columbiensis Fauna is defined by the first occurrence of either of the name givers.The upper limit has not been determined be- cause it occurs in the overlying Horquilla and Naco formations . Associ- ated species are Adetognathus lautus,A. spathus,Idiognathodus sinuo- sis, Spa_thognathodus minutus, Streptognathodus anteeccentricus, S. expansu s , and S. subere ctu s . This fauna correlates with Lane and Straka's (1974) Idiognatho- dus n. sp. Zone,with the upper middle subzone of Webster's (19 69) S. noduliferus --I. convexus Zone, and with Dunn's (1970a, 1970b) I. humerus-I. sinuosis Zone in Nevada.This fauna may be equivalent, in part, to the Profusulinella fusulinid zone,because in the upper Black Prince of the Dos C abe z a s Mountains near Willcox a primitive Profu s- linella was recovered (Ross and Sabins,1965).This fauna occurs in the uppermost Black Prince Limestone in the Swisshelm Mountains and in the basal beds of the Horquilla and Naco formations inall sections measured. TEMPORAL RELATIONSHIPS WITHIN THE LOWER PENNSYLVANIAN OF SOUTHEASTERN ARIZONA
Ross (1973) states that there are only two regional hiatusesof long duration within the Pennsylvanian and Permian of southeastern Ari- zona: one within the Derryan and one at the base of theMissourian. The Derryan hiatus marks the Black Prince-Horquilla-Naco boundary. Based on biostratigraphic evidence from my study, I have been able to determine more accurately the length of the Derryan hiatus .I have determined that it extends from early late Morrowan to middle Der- ryan in south -central Arizona to virtually no hiatus in extremesouth- eastern Arizona (Fig.5).
In the Swisshelm Mountains,located in the extreme southeast- ern portion of Arizona, the Black Prince and Horquilla represent almost continual sedimentation. All the conodont zones in this study are found in the Black Prince at this location and span the time from early middle Morrowan to early Derryan. The fusulinids at the base of the Horquilla here are also early Derryan.The contact between the Black Prince and the Horquilla is conformableThe hiatus, if any, between these forma- tions in the Swisshelm Mountains is minor. Northwestward from the Swisshelm, the Black Prince thins and has time transgressive upper and lower boundaries. The time represented by the Black Prince decreases until at Superior the formation is repre-
sented by only one conodont zone,the Idiognathodus sinuosis Zone, middle to early late Morrowan. The Naco Formation, which overlies the
15 SY M SE RIE S N CONODONTZONES STE >--zQ ---...-- N W NACO HORQUILLA\ \ \ SE Sp. co/oradoensfs LL1CC C3 y, N. co/umblensis 4-Q0%... 0 -.Q /. C onvexus zQ B L A C K i R ` N C E ::::::trIcds Q____IZ QZ (o>>-- (3oC ARIZONA N. bass/ert zwCL 2pa NW SE Arizona SeeFigure Figure 5. Temporal 4 for abbreviations. relationships within the Lower Pennsylvania of southeastern 17
Black Prince at Superior, has middle Derryan fusulinids at its base .The erosional contact is marked by a prominent Naco red chert pebble con- glomerate deposited in shallow channels cut into limestones of the un- derlying Black Prince.The hiatus between the Black Prince and the Naco at Superior ranges from the late Morrowan to the middle Derryan. In conclusion, the Derryan hiatus mentioned by Ross (1973) is of long duration in south -central Arizona, where it extends from late
Morrowan to middle Derryan.In extreme southeastern Arizona, though, the hiatus becomes virtually nonexistent. DEPOSITIONAL ENVIRONMENT
Studies of recent and ancient carbonate shelf and tidal -flat de- posits have been helpful in interpreting the depositional environments of the Black Prince Limestone, especially the studies of Laporte (1971),
Armstrong (1974),and Wilson (1974). Laporte (19 71) in his description of Paleozoic carbonate facies of the Central Appalachian shelf recognized and described four major facies: (1) tidal flat,(2) shallow subtidal, (3) deep subtidal, and (4)
carbonate buildups.In the Black Prince Limestone,the tidal -flat and shallow subtidal facies can be recognized. The environment of deposi- tion of these facies was from above mean low water to above wave base.
According to Ross (1973),these Black Prince deposits extended over a large area with virtually no other depositional environments represented.
In the Black Prince,the tidal facies is characterized by purple shales, laminated limestones and dolomites containing bird's-eye struc-
tures, limestone pebble conglomerates , and algal stromatolite s. The
rock types are shales, basal conglomerates, mudstone s,and sparsely
fossiliferous wackestones.In these beds, fossil diversity and abun- dance is low. At most, one or two conodont specimens were retrieved from these rocks. Adetognathus lautus was the only species present. In the shallow subtidal facies, grainstones, packstones, and fossiliferous wackestones predominate. The grainstones show cross- bedding, some good sorting, planar orientation of fossils, abraded
18 19
skeletal fragments,oolites,coated grains,and algal oncolites.The lepospondyl amphibians described by Thayer (197 3)are from an oncolite bed in the upper Black Prince of the Swis she lm Mountains. In the shallow subtidal facies, faunal diversity is high. There
are abundant crinoids,brachiopods, gastropods,and some phylloid al- gae .Chaetetes biostromes also havea scattered occurrence in this facies. Conodont diversity and abundanceare also high, especially in the packstones and wacke stones . CONCLUSIONS
This field and laboratory study has led me to the following con- clusions about the Black Prince Limestone: 1.The age of the Black Prince Limestone is early middle Morrowan to early Derryan. 2.Four conodont zones are recognizable in the Black Prince Lime-
stone: the N eognathodu s ba s s leri Zone,the Idioqnathodus s inuo s i s -Stre ptognathodu s ante e c ce ntricu s Zone , the Id iognath-
oide s convexus Zone,and the Spathoqnathodus coloradoens is - Neocinathodus columbiensis Fauna. 3.The hiatus separating the Black Prince Limestone from the Hor- quilla Limestone and the Naco Formation extends from late Morrowan to middle Derryan in south -central Arizona but de- creases to become almost nonexistent in the early Derryan of extreme southeastern Arizona. 4.The Black Prince represents a sequence of tidal -flat and shal-
low subtidal deposits.Conodonts are poorly represented in the tidal -flat facies and are well represented in the shallow sub - tidal facies.
20 SYSTEMATIC PALEONTOLOGY
Two methods of conodont taxonomy are in use today. Form species taxonomy, based on morphology, was established by Pander
(1856).Multielement taxonomy, based on naturally occurring assem- blages, was established by Hinde (1879). Until recently, form species taxonomy has been used by most conodont workers. As more workers recognized that the conodont animal had more than one kind of element, multielement taxonomy began to be more widely used. As a result of this,a dual nomenclature now exists for conodont taxonomy - -form species and multielement. In this study, I have used form species taxonomy because multielement taxonomy has not yet been widely applied to Lower Pennsylvanian conodonts.The generic concept in conodont taxonomy has recently been discussed by Sweet and Bergström (1970) ,
Austin (1972),Ellison (1972),and Huddle (1972). In this study, only platform species are described since most of the bar and blade taxa are of little biostratigraphic value in the Penn- sylvanian. The genera are listed alphabetically. The synonymies are limited to the original citation, the most recent reference with a com- plete synonymy, and any new additions.Descriptions of better known species are abbreviated. The total number of specimens studied is listed under "material." The distribution of each species in each measured
section is shown in Figure 6 (in pocket).Figured specimens are repos-
ited in the Paleontology collection at the Department of Geosciences, The University of Arizona, numbers UA 52850 -52875.
21 22 Genus Adetognathus Lane, 1967 Type species: Cavusgnathus lautus Gunnell,1933 Adetoqnathus lautus (Gunnell) ,1933 Fig. 7, nos. 1,2
Cavusqnathus lautus Gunnell, 1933,p. 286, Pl .31, figs. 67, 68; Pl . 33, fig. 9; Von Bitter, 1972, p. 61,62, P1. 4, figs.3a -3h,Pl. 5, figs. la -lh. Cavusgnathus zigantus Gunnell, 1933,p. 286, P. 32, figs. 7,8. Adetognathus lautus (Gunnell),Baesemann, 1973, p. 697,Pl. 2, figs. 24- 31,34; Lane & Straka, 1974, p. 64, fig.36, nos.17,21,22, 25-31; fig. '38, nos. 1 -4, 6 -8, 10 -15, 20; fig. 39, nos. 14,15, 19,20; fig. 40, nos. 1-3, 7 -14. Adetoqnathus Bantus (Gunnell),Baesemann, 1973, p. 696, Pl. 2 , figs. 36,38 -41. Description.--Left element. A marginal blade rises in height anteriorly from its attachment to the narrow platform. Margins are orna- mented with nodes or transverse ridges which do not extend to the center of the median trough. Large specimens may show some sinuosity of the
margins.The posterior end of the oral surface varies from rounded to
pointed.The aboral cavity is long,moderately deep, and narrow. It is pointed posteriorly and extends to the lower surface of the blade as a groove. Right element. This element is similar to the left except that the posterior end of the blade at its attachment to the platform bears an abnormally large denticle. Discussion.--Lane and Straka (1974) place A. qigantus in syn- onymy with A. lautus because the two species generally occur in the
same abundance and over the same stratigraphic range.Since A. lautus
is the type species of Adetoqnathus (Lane,1967),it must serve as the name bearer for the element pair. Figure 7. Adetognathus,Idiognathodus,Idiognathoides,, Neoqnathodus
1,2 - -Ade tognathu s lautus (Gunnell) :1, side view of leftele- ment of UA 52850, x45; 2, side view of right elementof UA 52851, X55. 3--Adetognathus spathus (Dunn) :oblique view of UA 52852, X43.
4,5,9,10 -- Idiognathodus sinuosis Ellison & Graves:4, ob- lique view of right element of UA 52853, x 55; 5, topview of left element of UA 52854, x 42; 9, top viewof right element of UA 52855, X58; 10, oblique view ofleft element of UA 52856, X62.
6,7 -- Idiognathoide s sinuatus Harris & Hollingsworth: 6,ob- lique view of UA 52861, x 54. 8, 12-- Idiognathoides convexus (Ellison & Graves): 8, oblique view of UA 52857, x 50; 12, top view of UA 52858, X 52. 11-- Idiognathoide s noduliferus (Ellison & Graves) : oblique view of UA 52859, x 52. 13 -- Neognathodusbassleri (Harris & Hollingsworth) :top view of UA 52862, X 52. 14-- Neognathodus columbiensis (Stibane) :oblique view of UA 52865, X56. 23
Figure 7. Adetognathus,Idiognathodus,Idiognathoide s, N e ognathodu s 24 Occurrence.---. lautus has beenreported from Upper Missis- sippian to Lower Permian (Baesemann,1973). In central Arizona, Reid (19 68) has reported this species from middle Derryan to Virgilian. Inthe Horquilla of the Dragoon Mountains , A. lautus rangesfrom Morrowan to Missourian (Micklin, 1969) .Totten (1972) reports it from Morrowan to
Virgilian in the Naco Hills.In my study, A. lautus occurs throughout the Black Prince,middle Morrowan to early Derryan, and in the basal beds of the Horquilla Limestone and the Naco Formation. Material.--477 left specimens and 578 right specimens. Figured Specimens. --UA 52850, UA 52851 (hypotype) .
Adetognathu s spathus (Dunn),1966 Fig. 7, no. 3 Cavusgnathus spatha Dunn, 1966, p. 1297, Pl. 157, figs. 3,7,8. Adetognathus spathus Dunn, Lane & Straka, p. 65, fig. 38, nos. 5,9, 16 -19; fig. 40, nos. 4-6. Description. -- Parapets merge posteriorly to form a short free blade which bears one or two short denticles that are conspicuous in lateral view. Some specimens have an enlarged denticle on the anterior blade at its junction with the platform on either the left or right side. Discussion.--A. spathus differs from other adetognathids by having a posterior blade. Occurrence .--A. spathus has been reported from the lower Mor- rowan to the Derryan(Dunn, 1966; Lane,Merrill, Straka, and Webster,
1971).In my study, A. spathus has been found throughout the Black
Prince , middle Morrowan to early Derryan). Material.--28 specimens.
Figured Specimen. --UA 52852 (hypotype). 25 Genus Idiognathodus Gunnell, 1931 Type species: Idiognathodus claviformis Gunnell, 1931 Idiognathodus sinuosis Ellison & Graves, 1941 Fig. 7, nos.4,5,9,10 Idiognathodus sinuosisEllison & Graves, 1941, p. 6, Pl.3, fig. 22; Lane & Straka, 1974, p. 81 -82, fig. 37, nos. 10-13,21; fig.43, nos. 1 -8, 10- 15,19,20. Idiognathodus humerus Dunn, 1966, p. 1300, Pl. 15 8 ,figs. 6,7. Idiognathodus delicatus Gunnell, Webster, 1969,p. 35 -37, Pl. 6, figs. 6,7.10,11; Baesemann, 1973, p. 699, P1. 1, figs. 23,24 (nonfigs.18,19 =Streptognathodus expansus) .
Description. --Left element. The wide inner margin is straight. The outer margin curves inwardly and is widest just posterior of the lobe. The long platform is ornamented with fine parallel transverse ridges which are sometimes slightly sinuous or form a chevron pattern centered on a very shallow median trough. The blade joins the platform in a me- dial position and continues posteriorly as a low carina for a third of the platform distance.Few to several ridges or rows flank the carina on both sides.A nodose lobe is usually present on the inner anterior mar- gin. In well -developed forms, a nodose lobe is also developed on the outer margin. Right element. This element is similar to the left except the maximum width is farther posterior. The platform is distinctly incurved and the transverse ridges trend diagonally and radiate from the inner side. Discussion.--Lane and Straka (1974) place I. humerus insyn- onomy with I. sinuosis. I have followed their example here.Left and right elements in this study occur in the same stratigraphic position and are of similar abundance. 26 In this species, I am also including forms thatresemble Idio- qnathodus maqnificus.There is a morphologic transition between these two form species,and it is difficult to separate them at any one point. Most of the I. maqnificus forms appear in the Derryan, so I do not agree with Webster (19 69) that these are just gerontic individuals, but I be- lieve them part of an evolutionary succession. Occurrence .- -Dunn (1970a) reports this species from the Mor- rowan of the southwestern United States .Lane and Straka (19 74) report it from the middle to upper Morrowan. In the Horquilla of the Naco Hills
(Totten, 1972), the range of I. sinuosis is from Derryan to De smoine sian. Reid (1968) and Micklin (1969) report the species from the Derryan to the Missourian of the Horquilla Limestone. In my study, I. sinuosis was found in the upper Morrowan to lower Derryan of the Black Prince and in the basal beds of the Horquilla and Naco formations. Material.--233 left specimens and 269 right specimens. Figured Specimens. --UA 52853 -UA 52856 (hypotypes).
Genus Idiognathoides Harris & Hollingsworth, 1933 Type species: Idiognathoides sinuata Harris & Hollingsworth, 1933
Idiognathoides convexus (Ellison & Graves),1941 Fig. 7, nos. 8,12 Polyqnathodella convexa Ellison & Graves, 1941, p. 9, Pl. 3, figs. 10,12,16. Idiognathoides convexus (Ellison & Graves),D unn,1970a, p. 334, Pl. 63, fig. 30, Text-fig. 11F; Lane, Merrill, Straka & Webster, 1971, Pl. 1, figs. 18,19. Description.--The blade joins thenarrow platform on either side and continues as a moderately high parapet. A longitudinalgroove is present next to the blade but is terminated by the first transverse 27
ridge.The transverse ridges on the oral surface are convex toward the posterior end of the platform. Discussion.--Specimens recovered in this study compare favor-
ably with those illustrated by Dunn (1970a),Webster (1969),and Lane,
Merrill, Straka, and Webster (1971). Occurrence.--Webster (19 69) reports I. convexus from lower to
middle Morrowan strata in Nevada. In the western United States,Dunn (1970a, 1970b) reports it from lower toupper Morrowan. In the type
Morrowan and in Oklahoma,it occurs in the upper Morrowan (Lane and
Straka,1974).In my study, I. convexus is restricted to the I. convexus
Zone,late Morrowan. Material. --17 specimens.
Figured Specimens .--UA 52857 and UA 52858 (hypotypes).
Idioqnathoides noduliferus (Ellison & Graves),1941 Fig. 7, no. 11 Cavusqnathus nodulifera Ellison & Graves, 1941, p. 4, Pl. 3, figs. 4, 6. Idiognathoide s noduliferus (Ellison & Graves),Lane & Straka, 1974, p. 85, fig. 35, nos. 1 -15; fig. 41, nos. 15-17. Description.--The platform is long, moderately narrow, with the posterior end pointed to rounded and with a median longitudinal groove .The blade joins the platform in a medial position and merges with the outer margin about a third of the platform distance posteriorly. One to three nodes are usually present on the anterior outer shoulder of the platform. These nodes may be fused intoa ridge or be completely absent. The margins may be ornamented with nodesor transverse ridges which extend nearly to the bottom of thegroove. 28 Discussion.--I. noduliferus has previously been assigned to
several different genera and species.I agree with Straka and Lane's (1970) name for this form species because of its possible phylogenetic relationships.
Occurrence. --I,noduliferus has been reported from the lower
Morrowan to the Derryan (Lane and Straka, 1974).Totten (1972) has reported this species from the Morrowan of the Horquilla Limestone of the Naco Hills.In the Black Prince Limestone, I. noduliferus is re- stricted to middle and upper Morrowan. Material.--16 specimens.
Figured Specimens .--UA 52859 (hypotype).
Idiognathoides sinuatus Harris & Hollingsworth, 1933 Fig. 7, nos. 6,7
Idiognathoides sinuata Harris & Hollingsworth, 1933, p. 201,Pl. 1, fig. 14. Idiognathodus corrugata Harris & Hollingsworth, 1933, p. 202, Pl. 1 figs. 7, 8a, 8b. Idiognathoide s sinuatus Harris & Hollingsworth, Lane & Straka, 1974, p. 88, fig. 37, nos. 14,15,18,20,23 -26; fig. 41, nos. 1 -14, 20 -27. Description.--Left element. The platform is long, narrow, and slightly bowed. The blade attaches to the left margin which is elevated above the right margin. A medial longitudinal groove is present and con- tinues posteriorly about a third of the platform length. The groove is paralleled by a high margin that is ornamented by coarse ridges. Right element. The right element is similar to the left except that the platform is not as narrow, the blade attaches to the right margin,
and both margins are the same height.Fine parallel transverse ridges ornament the platform and margins. 29 Discussion. Forms of I. sinuatus in this study compare favor- ably with forms that Lane and Straka (19 74) describe as being from the upper Morrowan (Lane and Straka, 1974, fig. 41, nos. 20,22). Lane and Straka place Idiognathodus corrugata into synonymy with I. sinuatus.
Occurrence. In the United States and in Europe,I. sinuatus has been found through the Pennsylvanian. In Arizona, Micklin (19 69) reports it from the Derryan of the Horquilla Limestone in the Dragoon
Mountains,and Totten (197 2) reports it from the Morrowan of the Hor- quilla of the Naco Hills. In my study, I. sinuatus is restricted to the middle and upper Morrowan of the Black Prince. Material.--4 left specimens and 2 right specimens.
Figured Specimens.--UA 52860, UA 52861 (hypotypes).
Genus Neognathodus Dunn, 1970a Type species: Polygnathus bassleri Harris & Hollingsworth, 1933
Neognathodus bassleri (Harris & Hollingsworth),1933 Fig. 7, no. 13; Fig. 8, nos. 1 -4
Polygnathus bassleri Harris & Hollingsworth, 1933, p. 198, Pl. 1, figs.13a -13e. Neognathodus bassleri (Harris & Hollingsworth),Lane & Straka, 1974, p. 74, fig. 37, nos. 16,17,19,22,31,32,37 -39; fig. 39, nos. 16-18,21-24; fig. 42, 17-24. Description.--A long free blade joins the platform in a medial position and forms a carina of fused nodes posteriorly and discrete nodes anteriorly. The carina, which extends the entire length of the platform, is paralleled by troughs which separate it from the margins.The margins are ornamented with nodes and /or transverse ridges. A large,deep, asymmetrical basal cavity is present. 30 Discussion.--Lane (1967) named two subspecies of N. bassleri, N. bassleri symmetricus and N. bassleri bassleri. He found these two subspecies to be separable stratigraphically and morphologically. In my study, the two subspecies intergrade and are found in the same
samples.Therefore,I have used only the species name.
Occurrence.- -N.bassleri has been reported from the middle
Morrowan.In Arizona, Totten (1972) has reported it from the Morrowan of the Naco Hills.In my study, N.bassleri is restricted to the N. bassleri Zone and to the lower part of the Id iognathodu s s inuo s i s- Streptognathodu s ante e cce ntricu s Zone of the Black Prince, middle Morrowan. Material. ---72 specimens.
Figured Specimens. --UA 52862 -UA 52864 (hypotypes).
Neognathodus columbiensis (Stibane),1967 Fig. 7, no. 14; Fig. 8, nos. 6,7
Streptognathodus columbiensis Stibane, 1967, p. 335, Pl. 36, figs. 1 -10. Description. - -The free blade joins the platform in a medial position and continues to the posterior tip as a carina.The highest denticles on the free blade occur in the anteriormost third of the free blade; from there the height diminishes and the denticles continue to the posterior tip as a distinct ridge.The free blade consists of eight or nine denticles and is slightly longer than the platform. The carina is separated from the margins of theplatform by deep troughs.The highly upturned platform marginsare strongly ribbed, with Figure 8.Neognathodus,Ráchistognathus,Spathognathodus , Streptognathodus,Genus A
1 -4. --Neognathodus ba s s leri (Harris & Hollingsworth) :1-3, top, oblique,lower views,respectively, of UA hypotype 52863, X50; 4, top view of UA 52864, X51. 5 --Rach istognathu s muricatus (Dunn) :top view of UA 52867, X71.
6,7-- Neognathodus columbiensis (Stibane) : top and lower views of UA 52866, X60. 8-- Spathognathodus minutus (Ellison): side view of UA 52869, X55. 9 -- Spathognathodu s coloradoe ns is Murray & Chronic: side view of UA 52868, X52. 10-- Streptognathodus expansus Igo & Koike: top view of UA 52872, X54. 11 -- Streptognathodus suberectus Dunn: top view of UA 52873, X55. 12 -14 -- Streptognathodus anteeccentricus Dunn: 12,13, left and right lateral views, respectively, of UA 52870, X75; 14, oblique view of UA 52871, X43.
15 -19- -Genus A, sp. A: 15, 16, top and lower viewsof UA 52874, X36; 17 -19, side, lateral, and top views,respec- tively, of UA 52875, X56. 31
Figure 8.Neognathodus,Rachistognathus,Spathognathodus, Strepto nathodu s ,Genus A 32
10 to 13 ribson the longer inner side and 7 to10 ribs on the outer side. These ribscan develop into nodes posteriorly. Discussion.--N. columbiensis most closely resembles N. bassleri. According to Lane (personal commun.,1975), N. columbiensis has a set -in carina and very deep adcarinal grooves or troughs,whereas N. bassleri has a raised carina.
Occurrence. --N.columbiensis occurs in the lower Derryan of
New Mexico and Nevada (Lane and Straka, 1974).In my study, N. columbiensis is restricted to the N. columbiensis-Spathoqnathodus coloradoensis Fauna of the Black Prince and Horquilla Limestones and Naco Formation, early Derryan. Material.--34 specimens.
Figured Specimens.--UA 52865, UA 52866 (hypotypes).
Genus Rachistognathus Dunn, 1966 Type species: Rachistognathus primus Dunn, 1966
Rachistognathus muricatus (Dunn),1965 Fig. 8, no. 5
Cavu sgnathu s muricata Dunn, 1965, p. 1147, Pl. 14 0,figs. 1,4. Rachistognathus muricatus (Dunn),Lane & Straka, 1974, p. 97, fig.35, nos. 16,17,24,30,31. Description.--The blade joins the platform on the left side and continues as a row of nodes for two -thirds of the platform distance pos- teriorly. At that point, the row of nodes is offset to the center of the platform and continues to the posterior tip of the platform as a carina. The right margin of the platform consists of a row of one to several nodes which continue one -half to two- thirds of the platform distance posteriorly. 33
Occurrence .--Lane and Straka (1974) report R. muricatus from
Chesterian to middle Morrowan. In the Naco Hills,Totten (197 2) reports Rachistognathus primus, which I consider tobe R. muricatus, from the
Morrowan.In the Black Prince,R. muricatus is restricted to the Neo- gnathodus bas s leri Zone, middle Morrowan. Material.--5 specimens.
Fig ured Specimens.--UA 52867 (hypotype).
Genus Spathognathodus Branson & Mehl, 1941 Type species: Spathodus primus Branson & Mehl, 1933 Spathognathodus coloradoensis Murray & Chronic, 1965 Fig. 8, no. 9 Spathognathodus coloradoensis Murray & Chronic, 1965,p. 606-607, Pl. 72, figs. 11 -13; Webster, 1969,p. 44, Pl. 7, fig. 7. Description. - -The small blade is straight to slightly bowed in oral view. Four to seven, high, erect denticles are present posteriorly. Anteriorly, 10 to 12 depressed, partially fused denticles are present, forming a low carina.The anterior denticles are low and recline anteri- orly. The first posterior denticle rises above the anterior carina.A widely flaring basal cavity is present and confined to the anterior half of the platform. The basal cavity is pointed posteriorly and rounded anteriorly. Discussion.--This distinctiveform is a good indicator for the Derryan in Arizona. Webster (Lane, Merrill, Straka, and Webster, 1971) states that S. coloradoensismay be a good index for the Middle Pennsylvanian. 34
Occurrence .--S,coloradoensis has beenreported from the Des - moine s ian of Colorado (Murray and Chronic, 1965) and the Derryan of
Nevada (Webster, 1969).It has been recovered in Arizona from the Derryan of the Horquilla Limestone of the Naco Hills (Totten, 1972) and the Dragoon Mountains (Micklin, 1969).Reid (19 68) reported it from the Derryan to the Missourian of the Naco Formation in south -central Arizona. In the Black Prince Limestone, S. coloradoensis is restricted to the lower Derryan. In my study, it was also found in the basal beds of the Hor- quilla and Naco formations, lower Derryan. Material.--17 specimens.
Figured Specimens.--UA 52868 (hypotype).
Spathognathodus minutus (Ellison),1941 Fig. 8, no. 8 Spathodus minutus Ellison, 1941, p. 120, figs. 50-52. Ozarkodina minuta (Ellison),Bae semann,1973, p. 704, Pl. 2, figs. 14, 15,19,20. Anchignathodus minutus (Ellison),Von Bitter, 1972, p. 65, P1. 6, figs. 2a-2i. Spathognathodus minutus (Ellison),Lane & Straka, 1974,p. 101, fig. 44, nos. 7,12. Description. --Small to large blade has 7to 12 sharply pointed denticles fused almost to the tips. The anterior main denticleis usually ornamented anteriorly with one to several small denticles.The aboral cavity is posterior of the main denticle. Occurrence .--S. minutus has beenreported from Upper Mis- sissippian to Lower Permian strata.It has been reported from Morrowan through Virgilian in Arizona (Totten, 1972; Reid,1968; and Micklin, 35
1969). In my study, S.minutus was found throughout the BlackPrince
Limestone, middle Morrowantolower Derryan strata. Material.--97 specimens.
Figured Specimen. -UA 52869 (hypotype).
Genus Streptognathodus Stauffer & Plummer,1932 Typespecies: Streptognathodus exce lsu s Stauffer & Plummer, 1932 Streptognathodu s anteeccentricus Dunn, 1966 Fig. 8, nos.12 -14 Streptognathodus anteeccentricus Dunn, 1966, p. 1302, Pl. 157, figs. 11,12; 1970a, p. 339, Pl. 62, figs.3,4,Text -fig. 9J. Streptognathodus parvus Dunn, Dunn, 1970a, p. 340, Pl. 64, figs. 8- 11, Text -fig. 9I. Description. - -The blade joins the platform in a medial position and continues posteriorly as a low, fused carina for about half to three- fourths of the platform length.The platform is ornamented posteriorly with parallel transverse ridges .The ridges are broken by the carina or by a trough which sometimes extends from the carina to the end of the platform. The anterior of the platform consists of narrow nodose parapets separated from the carina by narrow grooves.A small lobe of one to several nodes aligned parallel to the carina may be present along the inner end of the platform. In lateral view, the platform is moderately high and slopes toward the posterior tip. Discussion.--Since S. anteeccentricus intergrades with Strep- tognathodus parvus I have placed the two in the synonymy. Both of these forms occur in the same stratigraphic intervals.There is also some transition between S. anteeccentricus and Idiognathodus sinuosis,but 36 the latter is distinguished by the greater curvatureof the platform and the reduction of the median trough. Occurrence .--Dunn (1966) reports S. anteeccentricusfrom the Morrowan of the southwestern United States .Totten (1972) reportsthis species from the Morrowan to the Virgilian of theHorquilla Limestone in the Naco Hills. In my study, S. anteeccentricus was found inthe Black Prince fromupper Morrowan to lowerDerryan and in the basalbeds of the Horquilla and Naco formations. Material.--272 specimens. Figured Specimens .--UA 52870 -UA 52871(hypotypes).
Streptognathodus expanses Igo & Koike, 1964 Fig. 8, no. 10 Streptognathodus expansus Iqo & Koike, 1964, p. 189, Pl. 28, fig. Lane & Straka, 1974, p. 102 -103, fig. 43, nos. 9, 16 -18, 21 -26. Idioqnathodus delicatus Gunnell, Baesemann, 1973, p. 699 -670, Pl. 1, figs.18 ,19 (non figs.23, 24= Idiognathodu s sinuos is). Description. - -A median blade joins the moderately wide plat- form and continues posteriorly as a carina. From the carina to the pos- terior end of the blade, atrough extends through the transverse ridges that ornament the platform. The carina is flanked by ridges and by an inner elongate lobe of four nodes. In lateral view, the platform is arched highest at the junction of the platform and the blade. Discussion.--Lane and Straka (1974) suggest that this entirely left -side form might have been paired with Streptognathodus suberectus in the conodont animal. In this study, therewere too few specimens of either species to determine ifthey were paired. 37
Occurrence.---S. expansus has been reportedfrom the upper Morrowan by Lane and Straka (1974), from the middle Morrowan by Webster (1969), from the middle to upper Morrowan of japan by Koike
(1967),and from the Morrowan of Nevada by Dunn (1970a) .In my study, S. expansus was found in the top of the Black Prince, lower Derryan. Material.--1 specimen.
Figured Specimen.- -UA 52872(hypotype).
Streptoqnathodus suberectus Dunn, 1966 Fig. 8, no. 11 Streptoqnathodus suberectus Dunn, 1966, p. 1303, Pl. 157, figs. 4 -6, 10; 1970a, p. 340, Pl. 64, figs. 5 -7, Text-fig. 9H. Description.--The blade joins the platform in a medial position and continues posteriorly as a carina for about a third of the platform length. The carina is flanked on both sides by troughs.Margins of the troughs are ornamented by evenly spaced nodes.A lobe of several nodes is present that is parallel to the inner anterior side of the platform. The platform is slightly incurved and in lateral view is arched aborally. Discussion.--There are some intergradations between S. sub- erectus and S. anteeccentricus , but most forms in this study are distinct enough to be assigned to different species. Occurrence.---Dunn (1970b) and Webster (1969) report S. sub- erectus from the Morrowan of Nevada .It is restricted to the upper Mor-
rowan inArkansas (Lane,Merrill, Straka, and Webster, 1971). Inmy study, S. suberectus has been found in the upper Morrowan and lower Derryan of the Black Prince Limestone and in the basal beds of the Hor- quilla and Naco formations, lower Derryan. 38 Material.--15 specimens. Figured Specimens. --UA 52873 (hypotype) .
Genus A, sp. A Fig. 8, nos. 15 -19 Description.--In oral view, the small platform is short and narrow. The long free blade is about one to one and half times the length of the platform. The blade joins the platform in a medial position and continues posteriorly as a carina to the posterior tipe.The carina sometimes extends beyond the posterior tip. The blade is sometimes slightly bowed in top view. Margins separated by troughs flank the carina on both sides.Sometimes the carina lies close to the outer mar- gin. The carina and margin are unorname me d. In lateral view, the platform is high and flat. The blade is one and a half to two times the length of the platform. Denticles of the blade increase in height slightly toward the anterior. The basal cavity is wide and flaring, with the widest part just posterior of the junction of the blade and the platform .The basal cavity is pointed both posteriorly and anteriorly. It continues under the blade as a narrow groove. Discussion.--This species most closely resembles Neognatho- dus bassleri symmetricusand Streptognathodus anteeccentricus,. It dif- fers from thelatter by having a high, flat platform which lackstransverse ridges and by having a carina which always extends to the posterior tip. The platform of S. anteeccentricus slopes toward the posterior tip.
Occurrence.--Genus A, sp.A is found in theupper Morrowan of the Black Prince Limestone. 39 Material.--12 specimens.
Figured Specimens.---UA 52874,UA 52875 (hypotype). REFEREN CES
Armstrong, A. K.,1974, Carboniferous carbonate depositional models, preliminary lithofaciesand paleotectonic maps, Arctic Alaska: A.A.P.G. Bull. 58, p. 621 -645. Austin, R. L., 1972, Problems of conodont taxonomy with special refer- ence to Upper Carboniferous forms, in Lindström, M.,and Ziegler, W.,eds.,Symposium on conodont taxonomy: Geol. et Paleont.,SB1, p. 115 -126.
Bae semann,J. F.,1973, Missourian (Upper Pennsylvanian) conodonts of northeastern Kansas: Jour. Paleont., v.47, p. 689-710.
Branson, E. B.,and Mehl, M. G.,1933, Conodonts from the Bushberg Sandstone and equivalent formations of Missouri: Univ. Missouri Stud., v.8, p. 265 -299. 1941, Caney conodonts of Upper Mississippian age: Denison Univ. Sci. Lab. Jour., v.35, p. 167 -178.
Collinson, C.,1963, Collection and preparation of conodonts through mass production techniques: Illinois Geol. Surv. Circ. 343, 16p.
Dunham, R. J.,1962, Classification of carbonate rocks according to depositional texture, in Ham, W. H.,ed.,Classification of carbonate rocks - -a symposium: A.A.P.G. Mem.1, p. 108- 121.
Dunn, D. L.,1965, Late Mississippian conodonts from the Bird Spring Formation in Nevada: Jour. Paleont., v.39, p. 1145-1150. 1966, New Pennsylvanian platform conodonts from southwestern United States: Jour. Paleont.,v. 40, p . 1294-1303. 1970a, Middle Carboniferous conodonts from western United States and phylogeny of the platformgroup: Jour. Paleont. , v. 44, p. 312 -342. 1970b, Conodontzonation near the Mississippian -Pennsylvanian boundary in westernUnited States: Geol. Soc. America Bull., v. 81, p. 2959-2974.
Ellison, S. P., Jr.,1941, Revisionof the Pennsylvanian conodonts: Jour. Paleont.,v. 15, p. 107 -143.
40 41 Ellison, S. P., Jr., 1972, Conodont taxonomy in the Pennsylvanian, in Lindström, M., and Ziegler, W., eds., Symposium on cono- dont taxonomy: Geol. et Paleont. SB1 , p. 127-146.
Ellison, S. P., Jr., and Graves, R. W., Jr.,1941, Lower Pennsylvanian (Dimple Limestone) conodonts of the Marathon region, Texas: Univ. Missouri School Mines Metal. Bull. , Tech. Ser. 14, 13p. Gilluly,I., Cooper, J. R., and Williams, J". S., 1954, Late Paleozoic stratigraphy of central Cochise County, Arizona: U.S. Geol . Surv. Prof. Paper 266, 4 5p.
Gunnell, F. H.,1931, Conodonts from the Fort Scott Limestone of Missouri: Jour. Paleont.,v. 5, p. 244 -252. 1933, Conodonts and fish remains from the Cherokee, Kansas City, and Waubaunsee Groups of Missouri and Kansas. Jour. Paleont., v. 7, p. 261 -297.
Harris, R. W.,and Hollingsworth, R. V.,1933, New Pennsylvanian conodonts from Oklahoma: Amer. Jour. Sci., v.225, p.193- 204.
Hinde, G. J.,1879, On conodonts from the Chazy and Cincinnati Groups of the Cambro-Silurian, and from the Hamilton and Genesee division of the Devonian, in Canada and the United States: Quart. Jour. Geol. Soc. London, v. 35, p. 351 -368.
Huddle,J. W.,1972, Historical introduction to the problem of conodont taxonomy, in Lindström, M., and Ziegler, W. , eds., Sympo- sium on conodont taxonomy: Geol. et Paleont. SB1, p. 3 -16. Igo, H. , and Koike, T. ,1964, Carboniferous conodonts from the Omi Limestone, Niigata Prefecture, central Japan. (Studies of Asian conodonts, pt. I) :Trans. Proc. Palaeont. Soc. Japan, N.S. , v. 53, p. 179 -193. Koike, T. ,1967, A Carboniferous succession of conodonts from the Atetsu Limestone in southwest Japan. (Studies of Asiancono- donts, pt. VI): Tokoyo Kyoiku Daigaku, Sci. Reports 9c (93), p. 279 -318. Lane, H.P., 1967,Uppermost Mississippian and Lower Pennsylvanian conodonts from the type Morrowan region, Arkansas:Jour. Paleont., v. 41, p. 920-942.
Lane, H. R., Merrill, G. K. , Straka, J. T., Jr.,and Webster, G. D., 1971, North American Pennsylvanianconodont biostratigraphy, in Sweet, W. C. ,and Bergström, S. M. ,eds.,Symposium on conodont biostratigraphy: Geol. Soc.America Mem. 127,p. 395 -414. 42
Lane, H. R., Sanderson, G. A.,and Verville,G. J., 1972, Uppermost Mississippian-basal Middle Pennsylvanian conodontsand fusulinids from several exposures in the south-central and southwestern United States: 24th Internat.Geol. Cong., Section 7, p. 549-555.
Lane, W. R.,and Straka, j. J. , Jr., 1974, Late Mississippian and Early Pennsylvanian conodonts , Arkansas and Oklahoma: Geol. Soc. America Special Paper 153, 144 p. Laporte, L. F., 1971, Paleozoic carbonate facies of the central Appa- lachian shelf: Jour. Sed. Pet., v. 41, p. 724 -740.
Micklin, R. F.,1969, Fusulinids and conodonts of a Pennsylvanian - Permian section in the northern Dragoon Mountains, Cochise County, Arizona: unpublished M.S. thesis,University of Arizona, 257 p.
Murray, F. N.,and Chronic, J.,1965, Pennsylvanian conodonts and other fossils from insoluble residues of the Minturn Formation (De smoine sian),Colorado: jour. Paleont. , v.39, p.594-610.
Nations, J. D.,1963, Evidence for a Morrowan age for the Black Prince Limestone of southeastern Arizona: Jour. Paleont., v.37, p. 1252 -1264.
Pander, C. H.,1856, Monographia der fossilen fische de Silurischen Systems der Russian-Baltischen Gouvernements: K. Akad. Wiss. St. Petersburg, 91 p.
Reid,A. M.,1968, Biostratigraphy of the Naco Formation (Pennsylvan- ian) in south -central Arizona: unpublished Ph.D. dissertation, University of Arizona ,308 p. Ross, C. A. , 1973, Pennsylvanian and Early Permian depositional his- tory, southeastern Arizona: A .A . P . G . Bull., v. 57, p. 887-912.
Ross, C. A .,and Sabins, F. F., Jr.,1965, Early and Middle Pennsyl- vanian fusulinids from southeast Arizona: Jour. Paleont., v. 39, p. 173 -209. Stauffer, C. H. , and Plummer, H. J. , 1932, Texas Pennsylvanian cono- donts and their stratigraphic relationships: Texas Univ.Bull., v. 3201, p. 13 -50. Stibane , F. I. ,1967, Conodonten des Karbonsaus den nördlichen Anden Südamerikas. Neues Jahrb.Geologie u. Palëont.Abh., v.128, no. 3, p. 329 -340.
Straka, J. J. II, and Lane, H. P.,1970, Evolution ofsome Lower Penn- sylvanian conodont species: Lethaia,v. 3, p. 41-49. 43 Sweet, W. C., and Bergström, S. M., 1970, The generic concept in conodont taxonomy: North American Paleont. Convention1969, Proc. C., p. 157 -173.
Thayer, D. W.,1973, Pennsylvanian leopspondyl amphibians from the Swisshelm Mountains , Cochise County, Arizona: unpublished M.S. thesis,University of Arizona, 66 p.
Totten, D. K.,Jr.,1972, Biostratigraphy of some Late Paleozoic rocks in the Naco Hills area near Bisbee, Arizona: unpublished M.S. thesis, University of Arizona, 128 p. von Bitter, P. H.,1972, Environmental control of conodont distribution in the Shawnee Group (Upper Pennsylvanian) of eastern Kansas: Univ. Kansas Paleont. Inst. Art. 59, 105 p.
Webster, G. D.,1969, Chester through Deny conodonts and stratigraphy of northern Clark and southern Lincoln Counties, Nevada: Univ. Calif. Publ.Geol. Sci. 79, 121 p. Wilson, J. L., 1974, Characteristics of carbonate -platform margins: A.A.P.G. Bull., v. 58, p. 810 -824. r
i xo BLACK PRINCE LIMESTONE HORQUILLA LMS. FORMATIONS l' . I II 116 or i_ r r FOSSILS n w ,o < o° v° em b m 3 a 3 s 3ñ° -----_ __; __ _ 7. _ _ - = _ _ - ROCK TYPE 9c é o P ú LITHOLOGY I: 'IL 1 . ,I .., . ,,, ...... 0. _ l.l . SAMPLE LOCATION O 7 E o -0° ç o ' Z- áo ' t° 3x 3 ro _ Ade/opnarnur lovms ó - ' -g » , = w o m w m . mA, a w S m w e w w -< Al CT; m /eioqna//rOiess aD O w O Cn Dr z m O D ro m -, Spornognorhodvs mi autos C") 0 -I Z 1 CO - I Z = _ 3'g - a 7 G w o, /diggna/nodus srnugr,r o Rs z w z Cn W Z z aee/ovnorns a/nus w N -C - p 0 2. -^3 ó 3 N z - ro_v a a slrep/oynomodus gnrescronlrmur o w O z CO- C o S. r,Dereclus -1 Cn r -sl z Nr A Jdiognolnoldnconerys G b & 1 ® 6 O o 0 m D ÜO T 21 m N n m(g r nico O CO x 3 m 3 - r 5C ° i , Genvr A, spA. C w ` m = - w Q pG3 mG a É ° D o a D w w _ Idiogna/hoidss s,nuofur O 3 ° - g3 vwá w z w g to 41 Q w m _ Neognolnodus c0/umbiensis w w n
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5 g,nognglApdus colorodaens,s _ Neaynarhodus co/umDiensis