G. Arthur Cooper New Permian from West Texas

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SMITHSONIAN CONTRIBUTIONS T O PALEOBIOLOGY

N U M B E R 1

G. Arthur Cooper New P e r m i a n

and Richard E. Grant B r a c h i o p o d s

from

West Texas

SMITHSONIAN I N S T I T U T I O N PRESS

CITY O F W A S H I N G T O N

1969

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A B S T R A C T

Thirty-five new genera are described, 27 of them based on new species. They are classified by superfamily as follows:

ENTELETACEA:

Acosarina (A. dorsisulcata, new species).

DAVIDSONIACEA:

Goniarina (G. pyelodes, new species), Tropidel- asma (T. culmenatum, new species).

CHONETACEA:

Chonetinetes ( C reversus, new species), Micraphelia (M. scitula, new species), Rugaria (Chonetes hessensis R. E. King), Sulcataria (Chonetina? rostrata Dunbar and Condra), Undulella

(U. undulata, new species).

STROPHALOSIACEA:

Acritosia {A. magna, new spec- cies), Agelesia (Aulosteges triagonalis R. E. King). RICHTHOFENIACEA: Col- lumatus (C. solitarius, new species), Cyclacantharia (C. kingorum, new species), Her cose stria (H. cribrosa, new species), Hercosia (Richthofenia uddeni Bose), Sestropoma (5. cribriferum, new species).

PRODUCTACEA:

Anemonaria (A. inflata, new species), Dasysaria {D. undulata, new species), Oncosarina (O. spinicostata, new species), Thamnosia (T. anterospinosa, new species).

LYTTONIACEA:

Petas- maia (P. expansa, new species) .

RHYNCHONELLACEA:

Amphipella {A. arcaria, new species), Bryorhynchus (Camarophoria? bisulcata Shumard), Divaricosta {D. squarrosa, new species), Petasmatherus {P. opulus, new species), Phreno- phoria (P. subcarinata, new species), Pontisia (P. stehlii, new species), Strigir- hynchus (Rhynchonella? indentata Shumard), Tautosia (T. fastigiata, new species).

SPIRIFERACEA:

Lepidospirifer (L. angulatus, new species).

SPIRIFERINA-

CEA: Sarganostega {S. transversalis, new species), Xestotrema (Spirifera pulchra Meek) .

RETICULARIACEA:

Anomaloria (A. anomala, new species), Astegosia {Squ- amularia guadalupensis subquadrata Girty).

DIELASMATACEA:

Plectelasma (P.

kingi, new species).

CRYPTONELLACEA:

Texasia (T. elongata, new species).

The genus Cooperina Termier, Termier and Pajaud, based on material from the Glass Mountains, Texas, was assigned by its authors to the Thecideidina.

Evidence is adduced here to show that it is classified more properly among the Strophalosiacea of the Productidina and that it is unrelated to the thecideids.

Introduction

T h e Permian rocks of western Texas contain prob- ably the largest and most diversified Permian brachipod fauna in the world, numbering nearly

1000 species in more than 200 genera. Strata ex- posed in the many small mountain ranges in the

"trans-Pecos" area have come to be regarded as the standard for Permian correlations in all of North America, and therefore have been the subject of in- tensive study by many geologists. Pioneer work by G. H. Girty (1909) and P. B. King (1948) in the Guadalupe Mountains and by P. B. King (1931)

G. Arthur Cooper, Department of Paleobiology, U.S. Na- tional Museum, Washington, D.C. 20560. Richard E. Grant, Paleontology and Stratigraphy Branch, U.S. Geological Sur- vey, Washington, D.C. 20242.

and R. E. King (1931) in the Glass Mountains has made these two ranges preeminent as type sections.

The brachiopods of this area have been the sub- ject of study by the present writers for many years.

Brachiopod workers, other paleontologists, and

stratigraphers have learned of this study and have

become acquainted with the quality of much of the

silicified material through the media of lectures,

preliminary notes, formal and informal field trips,

visits to the U. S. National Museum, and personal

conversations. Therefore, it seems advisable to es-

tablish some of the new taxa that will be described

more fully later, to make available names that al-

ready are informally current, and to name common

genera that are important to discussions of age and

correlation. This avoids the awkward necessity of

referring to unnamed taxa in shorter discussions of

1

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Stratigraphy, age, a n d correlation such as those already presented by Cooper a n d G r a n t (1964, 1966).

T h i s p a p e r establishes a b o u t half of the genera that we expect to describe as new from this area. A few of these are based u p o n species already de-

scribed i n the literature, most are based o n new species. T h o s e t h a t remain to be established are relatively r a r e or of lesser i m p o r t a n c e to considera- tions of stratigraphic relationships. I n addition, we have taken this o p p o r t u n i t y to discuss the taxo- nomic position of the genus Cooperina, recently established by H . T e r m i e r , G. T e r m i e r , a n d Pajaud

(1967), r a t h e r t h a n delay it a n d thus risk having w h a t we consider an erroneous i n t e r p r e t a t i o n become "fossilized" in the literature.

Occurrences are given in the most recently a d o p t e d stratigraphic terminology by P. B. King

(1948), Ross (1959), a n d Cooper a n d G r a n t (1964, 1966), b u t older equivalent names are men- tioned for clarity in the detailed listing of loca- tions. Abbreviations: U S N M = U.S. N a t i o n a l Mu- seum, U S G S : = U . S. Geological Survey, Y P M = Yale Peabody Museum, A M N H = American M u s e u m of N a t u r a l History, T = University of Texas, T - B E G = Texas, B u r e a u of Economic Geology.

W e here acknowledge critical review of the man- uscript by J. T . D u t r o , Jr., a n d W . J. Sando, U.S.

Geological Survey.

S u p e r f a m i l y ENTELETACEA W a a g e n , 1 8 8 4 Acosarina C o o p e r a n d Grant, n e w g e n u s

DIAGNOSIS.—Shell small a n d strongly biconvex, widest at m i d l e n g t h ; anterior commissure rectimarginate to sulcate; palintropes well developed, inter- areas distinctly visible on articulated shell. Pedicle valve interior with low b u t long m e d i a n septum, e x t e n d i n g to or slightly beyond m i d l e n g t h ; dental plates short.

TYPE-SPECIES.—Acosarina dorsisulcata Cooper a n d G r a n t , new species.

R E M A R K S . — T h i s genus most nearly resembles Or- thotichia, differing in its rectimarginate to sulcate a n t e r i o r commissure, a n d long b u t low m e d i a n sep- t u m in the pedicle valve. Its distinct interarea a n d conspicuously wider hinge distinguish it readily

from Rhipidomella Oehlert, as d o its other un- d o u b t l y o r t h o t i c h i i d i n t e r n a l features.

Acosarina dorsisulcata C o o p e r a n d Grant, new species

PLATE .5: FIOURES 19-23

Shell small for genus, slightly wider t h a n long, subequally biconvex; surface multicostellate a n d with r a n d o m l y scattered tubules; anterior commissure weakly sulcate, normally slightly e m a r g i n a t e as well. H i n g e w i d t h a b o u t half t h e valve w i d t h , interarea distinct, longitudinally curved reflecting curvature of pedicle beak; pedicle valve slightly swollen to form low fold.

Pedicle valve interior with small teeth, short dental plates; m e d i a n s e p t u m low, fairly thick, extending beyond d e n t a l plates to n e a r m i d l e n g t h of valve. Brachial valve interior with long curved brachiophores h a v i n g thick, widely flaring supports;

cardinal process thick a n d t r i a n g u l a r . T Y P E S . — H o l o t y p e U S N M 150242b.

STRATIGRAPHIC OCCURRENCE.—Bone Spring Lime- stone.

L O C A L I T Y . — U S N M 728e, Sierra Diablo.

R E M A R K S . — T h i s species is characterized by its relatively small size a n d its sulcate commissure. I t differs from Rhipidomella mesoplatys R. E. King (1931) (herein assigned to Acosarina) i n these two features a n d in its stronger biconvexity.

S u p e r f a m i l y DAVIDSONIACEA K i n g , 1 8 5 0

Goniarina C o o p e r a n d Grant, n e w g e n u s

DIAGNOSIS.—Small conical schuchertellids w i t h long interarea; rectimarginate; p s e u d o p u n c t a t e ; costellate, costellae with filae. Pedicle valve i n t e r i o r with deep delthyrial cavity; d e n t a l plates absent.

Brachial valve i n t e r i o r with 2 lobes of cardinal process bisected by thin s e p t u m b u t lobes a n d s e p t u m all fused i n t o thick curved plate covered by arched chi- lidium; adductor muscle field bisected by short median ridge e x t e n d i n g forward beyond muscle marks.

TYPE-SPECIES.—Goniarina pyelodes Cooper a n d G r a n t , new species.

R E M A R K S . — T h i s genus most nearly resembles Schuchertella Girty a n d Derbyoides D u n b a r a n d C o n d r a . It differs from Schuchertella in its conical shell with consequent elongated a n d flat interarea and, internally, by its originally septate cardinal process, its u n u s u a l l y long, slender, a n d curved brachiophores (unusual i n any d a v i d s o n i a c e a n ) ,

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N U M B E R 1

a n d especially by its i r r e g u l a r m y o p h r a g m in the b r a c h i a l valve. T h e m y o p h r a g m begins between t h e a d d u c t o r m a r k s a n d extends to the a n t e r i o r edge of muscle field, in contrast to t h a t of Schuch- ertella i n which the m e d i a n ridge or m y o p h r a g m , if present, begins b e h i n d the muscle area a n d extends only to near its m i d d l e .

Goniarina differs from Derbyoides externally in t h e concial shape of the shell a n d the long interarea; it differs internally in the lack of a secondary m e d i a n s e p t u m in the pedicle valve a n d in the lack of the cuplike structures t h a t enclose the bachio- phores of Derbyoides.

Goniarina pyelodes C o o p e r a n d Grant, n e w s p e c i e s

PLATE 4: FIGURES 26-30

Small for genus, highly variable, normally twisted or b e n t , shallowly to deeply conical; hinge slightly n a r r o w e r t h a n m a x i m u m w i d t h of shell, ends slightly a u r i c u l a t e . Costellae low, r o u n d e d , weakly c r e n u l a t e d , increasing in n u m b e r by intercalation, n u m b e r i n g 15-22 per 5 m m on pedicle valve, 18-24 p e r 5 m m o n brachial valve; a t t a c h m e n t scar normally present near pedicle valve beak; interarea wide, long, nearly flat; perideltidial area obscurely rharked, occupying m o r e t h a n half the w i d t h of interarea.

Pedicle valve interior with h i n g e teeth keeled, b u t w i t h o u t d e n t a l plates. Brachial valve i n t e r i o r w i t h cardinal process short, bifid, longitudinally grooved; b r a c h i o p h o r e s nearly b u r i e d in sides of socket plates, fused to sides of cardinal process;

muscle area bisected by long, low m e d i a n ridge.

T Y P E S . — H o l o t y p e U S N M 15041 Ig.

STRATIGRAPHIC OCCURRENCE.—Neal R a n c h Forma- tion of Ross (1959).

L O C A L I T Y . — U S N M 701k, Glass M o u n t a i n s .

R E M A R K S . — A n o t h e r species t h a t belongs to Goniarina is Schuchertella permiana Stehli (1954, p. 298, pi. 17: figs. 19-23). Goniarina pyelodes differs i n its smaller size, m o r e deeply conical shape w i t h h i g h e r interarea, weaker costellation, a n d lack of a n o d e n e a r t h e anterior e n d of the s e p t u m in t h e brachial valve.

Tropidelasma C o o p e r a n d Grant, n e w g e n u s D I A G N O S I S . — M e d i u m sized to large, finely costellate w i t h elongated pedicle valve a n d convex, lid-

like brachial valve. I n t e r a r e a b r o a d ; pseudodelti- d i u m with n a r r o w elevated l o n g i t u d i n a l fold. Pedi- cle valve i n t e r i o r with greatly elongated c a r d i n a l process h a v i n g deeply slit prongs. Resembles Strep;

torhynchus i n its lack of d e n t a l plates b u t t h e folded p s e u d o d e l t i d i u m a n d greatly elongated cardinal process separate the two.

T Y P E - S P E C I E S . — Tropidelasma culmenatum Cooper a n d G r a n t , new species.

Tropidelasma culmenatum C o o p e r a n d Grant, n e w species

Variable in form, usually subconical; pedicle valve elongated; brachial valve a moderately convex lid.

I n t e r a r e a long; p s e u d o d e l t i d i u m nearly flush with the intearea b u t m a r k e d medially by a p r o m i n e n t narrow, l o n g i t u d i n a l fold. Greatest w i d t h at a b o u t midvalve. Surface costellate, costellae n u m b e r i n g a b o u t 3 in o n e millimeter at a n t e r i o r m a r g i n .

Pedicle valve often distorted; beak small a n d usually acute; sides concave to gently convex; me- d i a n region longitudinally subcarinate. Brachial

valve with p r o m i n e n t swollen u m b o ; m e d i a n a n d anterior regions gently flattened.

Measurements in mm

holotype 147829a

brachial valve length length

32.4 32.4 42.9 30.0

width 39.2 50.6

hinge width 36.0 44.5

thickness 51.9 47.6 T Y P E S . — H o l o t y p e U S N M 147829b; paratypes 147829a, c-1.

STRATIGRAPHIC OCCURRENCE.—Neal R a n c h Forma- tion of Ross (1959).

L O C A L I T Y . — U S N M 701h, Glass M o u n t a i n s . REMARKS.—Resembles Streptorhyyichus? undula- tiim R. E. King from the Skinner R a n c h F o r m a t i o n b u t is m u c h larger, m o r e elongate, with a wider hinge, a n d with a wider p s e u d o d e l t i d i u m t h a t occu- pies one-third of the interarea.

S u p e r f a m i l y CHONETACEA B r o n n , 1 8 6 2

Chonetinetes C o o p e r a n d Grant, n e w g e n u s DIAGNOSIS.—Small, alate, dorsally deeply concave, anteriorly t a p e r i n g c h o n e t i d with erect cardi-

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n a l process h a v i n g a d e e p alveolus; m e d i a n s e p t u m short; a n d e r i d i a r e d u c e d b u t anterior slope of brachial valve deeply sulcate a n d lateral regions elevated. Suggests Chonetina Krotov i n exterior form b u t is smooth a n d its interior is n o t biseptate as in Chonetina.

TYPE-SPECIES.—Chonetinetes reversus Cooper a n d G r a n t , new species.

Chonetinetes reversus C o o p e r a n d Grant, n e w species

Small, s u b t r i a n g u l a r with wide hinge a n d acutely p o i n t e d ears. Deeply concavo-convex with anterior t a p e r i n g a n d narrowly r o u n d e d . Spines oblique, n u m b e r i n g 3 or 4 on each side of the beak.

Pedicle valve medially sulcate posteriorly, the sulcus disappearing anteriorly. I n t e r a r e a moderately long, slightly curved, orthocline. P s e u d o d e l t i d i u m strongly curved, moderately long. Dorsal valve deeply concave, with a p r o m i n e n t , narrow, short fold at the posterior. I n t e r a r e a short, hypercline.

Pedicle valve interior with d e e p u m b o n a l cham- ber divided by a stout m e d i a n septum. Apical callosity thick. Dorsal valve interior with large cardinal process, short m e d i a n s e p t u m facing an anterior, l o n g i t u d i n a l c h a n n e l b o u n d e d by steep sides.

Lateral areas swollen.

Measurements in mm brachial

valve hinge mid-

length length width width thickness holotype 9.2 7.4 13.3 10.0 3.2 T Y P E S . — H o l o t y p e U S N M 153193a; paratypes 153193b-l.

STRATIGRAPHIC OCCURRENCE.—Road C a n y o n For- m a t i o n .

L O C A L I T Y . — U S N M 71 Oh, Glass M o u n t a i n s . R E M A R K S . — T h i s is the largest a n d most robust species of the t h r e e recognized in the collections.

cardinal process, thick anderidia, short m e d i a n sep- t u m a n d p r o m i n e n t l y elevated lateral regions.

TYPE-sPECiES.-^Micraphelia scitula Cooper a n d G r a n t , new species.

R E M A R K S . — T h e very small size of this chonetid invites comparison with only two other genera. I t differs from Tornquistia P a e c k e l m a n n in absence of two p r o m i n e n t divergent ridges in the m e d i a n region of the brachial valve. I t differs from Chone- tina in lacking the distinctive fold a n d sulcus that characterize t h a t genus, a n d in its smooth r a t h e r t h a n finely costellate surface.

Micraphelia scitula C o o p e r a n d Grant, n e w species

Shell small, transversely s u b q u a d r a t e ; posterior m a r g i n with a b o u t 4 o b l i q u e spines; u m b o n a l a n d medial regions of pedicle valve strongly inflated; lateral slopes steep; brachial valve less strongly inflated.

Pedicle valve interior with small teeth, thick apical callosity, short m e d i a n s e p t u m c o n t i n u e d as low ridge to n e a r m i d l e n g t h . Brachial valve interior with small cardinal process a n d short, poorly defined prosocket ridges; breviseptum slender; visceral disc marginally thickened progressively with age;

m a r g i n with broad granulose flattening; visceral region with a b u n d a n t endospines.

T Y P E S . — H o l o t y p e U S N M 153725b; p a r a t y p e 153725e.

STRATIGRAPHIC OCCURRENCE.—Bell C a n y o n For- m a t i o n (Hegler, Pinery, a n d R a d e r M e m b e r s ) .

L O C A L I T Y . — H o l o t y p e : U S N M 731, Delaware Basin.

R E M A R K S . — S h u m a r d ' s (1859) specimens of Cho- netes permianus also may belong to this species, b u t they are irretrievably lost. Since their relationships cannot be ascertained, the n a m e is left w i t h

the lost specimens a n d is effectively nullified.

Micraphelia C o o p e r a n d Grant, n e w g e n u s

DIAGNOSIS.—Small, s u b q u a d r a t e chonetid with smooth exterior; commissure n o t folded; hinge ends n o t e x t e n d e d ; pedicle valve interior with short me- d i a n s e p t u m ; dorsal valve i n t e r i o r with small

Rugaria C o o p e r a n d Grant, n e w g e n u s

DIAGNOSIS.—Small, strongly costate Chonetacea h a v i n g a large cardinal process with deep alveolus, short m e d i a n s e p t u m a n d a broad, strongly endo- spinose anterior slope in the brachial valve. Re-

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N U M B E R 1

sembles Micraphelia i n form b u t is costate; resembles some species assigned to Plicochonetes Paeckel- m a n n b u t has a well-developed m e d i a n s e p t u m .

TYPE-SPECIES.—Chonetes hessensis R . E. King ( 1 9 3 1 , p . 61, pi. 9: figs. 21, 2 2 ) .

T Y P E S . — L e c t o t y p e Y P M 10820 (R. E. King.

1931, pi. 9: fig. 2 2 ) ; p a r a t y p e T 10589.

STRATIGRAPHIC OCCURRENCE.—Hess F o r m a t i o n ( T a y l o r R a n c h M e m b e r ) .

L O C A L I T Y . — R . E. King 107 ( 1 9 3 ] ) „ G l a s s M o u n - tains.

Sulcataria C o o p e r a n d Grant, n e w g e n u s

DIAGNOSIS.—Small, smooth chonetacean having the pedicle valve deeply sulcate a n d brachial valve flatly concave a n d with a fairly strong dorsal me- d i a n fold. Pedicle valve interior with broad, elevated a d d u c t o r ridge a n d flattened margins; brachial valve i n t e r i o r with thick m e d i a n s e p t u m a n d strongly lobed anterior visceral region. Resembles Chonetinella R a m s b o t t o m externally b u t differs in b e i n g smooth a n d having m o r e strongly developed visceral region in t h e brachial valve.

TYPE-SPECIES.—Chonetina? rostrata D u n b a r a n d C o n d r a (1932, p . 150, pi. 19: figs. 1-3, 5-7).

T Y P E S . — L e c t o t y p e Y P M S2166a ( D u n b a r a n d C o n d r a , 1932, pi. 19: fig. 1) ; paratypes Y P M S2166b-f.

STRATIGRAPHIC OCCURRENCE. — P e n n s y l v a n i a n , South Bend Sandstone a n d Shale of P l u m m e r a n d Moore (1922).

LOCALITY.—2.5 miles southeast of Gunsight, T e x a s .

Undulella C o o p e r a n d Grant, n e w g e n u s

DIAGNOSIS.—Small, smooth, chonetacean with a b r o a d m e d i a n sulcus in t h e pedicle valve a n d long spines given off at a r i g h t angle. Brachial valve with small cardinal process, w i t h o u t a d d u c t o r di- viding ridges a n d with a short breviseptum. Antero- m e d i a n p a r t of visceral region with a deep pit.

Suggests Sulcataria in external form b u t has vertical posterior spines a n d different brachial valve interior.

TYPE-SPECIES.—Undulella undulata Cooper a n d G r a n t , n e w species.

Undulella undulata C o o p e r a n d Grant, n e w species

Small, transversely r e c t a n g u l a r with r o u n d e d sides;

cardinal extremities nearly a right angle; posterior m a r g i n with 4 erect spines, the o u t e r 2 a t t a i n i n g a length of 2.5 m m . Pedicle valve w i t h the posterior half flatly convex a n d the anterior half strongly b e n t in a gentle curve toward the brachial valve.

Beak small; interarea moderately long, apsacline;

p s e u d o d e l t i d i u m strongly convex. Brachial valve with cardinal extremities flattened; most concave posteromedially; anterior half gently curved in a dorsad direction to form a broad u n d u l a t i o n .

Measurements in mm brach-

ial sur-

valve face hinge mid- thick- lengtli length length width width height ness

holotype 7.1 6.2 8.5 12.2 12.0 2.3 1.7 l!>2070g 6.4 6.0 7.0 11.3 11.0 2.0 1.2 T Y P E S . — H o l o t y p e U S N M 152070b; paratypes 152070b, a, c-r; 153186a.

STRATIGRAPHIC OCCURRENCE.-—Word F o r m a t i o n (Willis R a n c h M e m b e r ) .

L O C A L I T Y . — U S N M 706e, Glass M o u n t a i n s . R E M A R K S . — N o other species of this genus has been described to which this one may be c o m p a r e d . T w o other species are present in the collections.

S u p e r f a m i l y STROPHALOSIACEA S c h u c h e r t , 1 9 1 3

Acritosia C o o p e r a n d Grant, n e w g e n u s

DIAGNOSIS.—Low conical, o b l i q u e in y o u t h b u t becoming m o r e symmetrical w i t h g r o w t h ; c u p margin flaring; attached by n u m e r o u s rhizoid spines with circular cross sections w i t h o u t webbing. Pedi- cle valve interior lacking s e p t u m ; protective spines on a n t e r i o r side only; brachial valve lodged obliquely. Brachial valve flat to slightly concave; interior with short, erect cardinal process; muscle area slightly thickened; endospines few b u t strong.

TYPE-SPECIES.—Acritosia magna C o o p e r a n d G r a n t , new species.

REMARKS.—Acritosia most nearly resembles Te- guliferina Schuchert a n d LeVene externally, b u t

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differs i n h a v i n g rhizoid spines t h a t are circular in cross section a n d have n o weblike shelly material on t h e m or between them. I t differs from the new genus Hercosia (described below) in lacking a m e d i a n s e p t u m in the pedicle valve. It differs from the new genus Cyclacantharia (also described below) , which also is w i t h o u t a septum, in its lack of an elevated muscle m o u n d in the apex of the pedicle valve a n d in its protective spines, which are located only at the anterior of the i n n e r m a r g i n of the pedicle valve r a t h e r t h a n s u r r o u n d i n g it completely as in Cyclacantharia.

Acritosia magna C o o p e r a n d Grant, n e w species

PLATE 5: FIGURES 17, 18

Large, thin shelled, n a r r o w or spreading; m a r g i n flared; anterior side flattened, b e a r i n g m a n y short spines just inside anterior m a r g i n ; apex b l u n t , p o i n t i n g posteriorly; a t t a c h m e n t surface small; surface wrinkled; rhizoid spines slender.

Pedicle valve i n t e r i o r with low m e d i a n myo- p h r a g m bisecting muscle area; aulacoterma distinct, just inside protective spines, e x t e n d i n g obliquely a r o u n d valve. Brachial valve interior with n a r r o w cardinal process; buttress ridge a n d breviseptum low a n d obscure.

T Y P E S . — H o l o t y p e U S N M 151739a.

STRATIGRAPHIC OCCURRENCE.—Neal R a n c h Forma- tion of Ross (1959) .

L O C A L I T Y . — U S N M 701k, Glass M o u n t a i n s . R E M A R K S . — T h i s is the largest species of the genus, distinguished by its flared pedicle valve m a r g i n a n d relatively thin shell walls. Of described species t h a t belong to this genus, A. magna differs from Teguliferina? teguliferoides Stehli, 1954 (not R. E.

King, 1931), in its large size, t h i n n e r shell, a n d somewhat fewer a n d more slender rhizoid spines.

Agelesia C o o p e r a n d Grant, n e w g e n u s

DIAGNOSIS.—Small, t r i a n g u l a r aulostegid with dorsal valve p i t t e d b u t n o t spinose; pedicle valve w i t h n a r r o w hinge a n d strong muscle callosity; brachial valve with thickened a d d u c t o r scars b u t widely bilobed cardinal process. T h i s genus is similar to Girlasia De Gregorio, 1930, in possessing a widely bilobed cardinal process b u t differs in hav-

ing thick rhizoid spines on the ears a n d lateral slopes a n d the interarea vestigial or absent.

TYPE-SPECIES.I—Aulosteges triagonalis R. E. King (1931,p. 94, pi. 27: figs, l a , b ) .

T Y P E S . — H o l o t y p e Y P M 11833; illustrated hypotypes, U S N M 151514a, 153834a.

STRATIGRAPHIC OCCURRENCE.—Cathedral M o u n - tain F o r m a t i o n .

L O C A L I T Y . — H o l o t y p e : R. E. King 231 (1931).

Hypotypes: U S N M 703bs, Glass M o u n t a i n s . S u p e r f a m i l y RICHTHOFENIACEA W a a g e n , 1 8 8 5

Collumatus C o o p e r a n d Grant, n e w g e n u s DIAGNOSIS.—Small, noncolonial or solitary richthofeniacean forming squat cylinders attached by a b r o a d base. A p e r t u r e of pedicle valve covered by a calcareous net as in Hercosestria Cooper a n d G r a n t (described b e l o w ) . N o s e p t u m i n the pedicle valve.

A t t a c h m e n t spines absent, their place being taken by concentric sheets of shell substance s u r r o u n d i n g the c u p a n d cementing the shell to the substrate.

Lack of a n c h o r i n g spines sets this genus a p a r t from all other richthofeniaceans.

TYPE-SPECIES.—Collumatus solitarius Cooper a n d G r a n t , new species.

Collumatus solitarius C o o p e r a n d Grant, new species

Small, subcylindrical to laterally elliptical a n d with e x p a n d e d base. A p e r t u r e of cylinder usually constricted a n d covered by a protective calcareous net. Pedicle valve interior with low m y o p h r a g m a n d flabellate diductor scars. Dorsal valve located a b o u t one-third the valve length above the floor;

cardinal process small, bilobed; a d d u c t o r scars elongate, thickened.

holotype

length 12.0

width 12.5

thickness 6.5 T Y P E S . — H o l o t y p e U S N M 153548a; paratypes 153548b-g.

STRATIGRAPHIC OCCURRENCE.—Road C a n y o n For- m a t i o n ( t o p ) .

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N U M B E R 1

LOCALITY.—USNM 736x, Glass Mountains.

COMPARISON.—This species is unique, and its absence of anchoring spines distinguishes it from Hercosestria and Sestropoma, both of which have calcareous nets covering the aperture.

Cyclacantharia Cooper and Grant, new genus DIAGNOSIS.—Richthofeniaceans having the entire rim of the ventral valve provided with protective spines; ventral valve having a thick muscle callosity but no median septum. In the latter respect it is unlike Hercosia Cooper and Grant (described below).

TYPE-SPECIES.—Cyclacantharia kingorum Cooper and Grant, new species.

Cyclacantharia kingorum Cooper and Grant, new species

Richthofenia permiana Girty [not Shumard], 1909, p. 283 pi. 31: figs. 1-3.—Bose [not Shumard], 1916, p. 37, pi. 1:

figs. 1-16; pi. 2: figs. 8, 15; pi. 3: figs. 1, 4—7.

Prorichthofenia permiana R. E. King [not Shumard], 1931, p.

99, pi. 29:, figs. 6-9; pi. 30: figs. 9-13.—Muir-Wood and Cooper [not Shumard], 1960, p. 139, pi. 29: figs. 1-15.

Fairly large cones, the width about three-fifths the length of the cone with aperture surrounded by striated spines, those of the anterior side longer and extending beyond the middle of the cup. Aper- ture flared widely in some specimens. Surface smooth. Anchor spines moderately thick and stout.

Brachial valve thin, located three-fifths to two-thirds the length from the apex; surface finely spinose.

Pedicle valve interior with vesiculose tissue extending for about half the length of the cone;

muscle callosity thick, subcarinate but without a septum. Brachial valve interior with small bilobed cardinal process and a few long, stout endospines at the anterior.

Measurements in mm*

brachial valve

length length width thickness height holotype 22.0 23.7 23.2 22.0? 31.0

* According to measurement directions of Muir-Wood and Cooper, 1960, p. 19.

TYPES.—Holotype USNM 153831; figured paratypes USNM 123917, 123918, 124138, 124139,

12414()a,b, 124164a-c, 124165a, 124166 (all figured by Muir-Wood and Cooper, 1960, pi. 29: figs. 1-8,

10, 14).

STRATIGRAPHIC OCCURRENCE.—Word Formation (Willis Ranch Member).

LOCALITY.—USNM 706e, Glass Mountains.

REMARKS.—This is larger than the common Richthofenia uddeni Bose of the Leonard Series

(Cathedral Mountain Formation) and differs fur- ther in having a complete ring of spines around the inner margin of the cup and in not having a median septum in the pedicle valve.

Hercosestria Cooper and Grant, new genus DIAGNOSIS.—Small richthofeniacean with strong bladelike median septum in the pedicle valve, the aperture of which is covered by a slightly convex netlike cover. Brachial valve with aborted anterior endospines. Differs from Sestropoma Cooper and Grant (described below) in having a strong ventral median septum and a low net across the aperture.

TYPE-SPECIES.—Hercosestria cribrosa Cooper and Grant, new species.

Hercosestria cribrosa Cooper and Grant, new species

Medium-sized, widely conical richthofeniacean with aperture covered by a fine-meshed calcareous net;

brachial valve deeply inset at about midway of the cone. Rim of cone squamose; sides smooth, spines numerous.

Measurements in mm length width thickness height holotype 18.2 26.2 16.7 34.5 TYPES.—Holotype USNM 151804; paratype USNM 153199.

STRATIGRAPHIC OCCURRENCE.—Road Canyon For- mation.

LOCALITY.—USNM 702c, 703a, Glass Mountains.

Hercosia Cooper and Grant, new genus DIAGNOSIS.—Medium-sized richthofeniaceans having a long bladelike median septum in the pedicle valve and protective spines only on the ventral

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side of the c u p r i m . Suggests Hercosestria internally b u t lacks t h e netlike calcareous cover over the c u p .

TYPE-SPECIES.^—Richthofenia uddeni Bose (1916, p. 43, pi. 2: figs. 1-7, 9, 13; pi. 3: fig. 2 ) .

T Y P E S . — L e c t o t y p e T - B E G 7643 (Bo.se, 1916, pi.

2: figs. 4, 7, 9 ) .

L O C A L I T Y . — O l d W o r d R a n c h , Glass M o u n t a i n s , Hess Canyon q u a d r a n g l e , T e x a s .

Sestropoma C o o p e r and Grant, n e w g e n u s

DIAGNOSIS.—Like Cyclacantharia internally b u t with a strongly convex netlike cover over the aper- t u r e of the cone.

TYPE-SPECIES.—Sestropoma cribriferum Cooper a n d G r a n t , new species.

vex; trail with distinct sulcus. Surface nearly smooth except for n u m e r o u s indistinct costellae on trail; spines few: 1 row on each lateral slope, scattered individual spines on trail a n d visceral disc.

Pedicle valve interior with r u d i m e n t a r y ear baffles;

brachial valve interior with small sessile cardinal process with broad zygidium; breviseptum reduced.

TYPE-SPECIES.—Anemonaria infiata Cooper a n d G r a n t , new species.

R E M A R K S . — T h e most obvious external resemblance of Anemonaria is to Kozlowskia Frederiks.

Anemonaria differs in having a different arrange- m e n t of spines, a zygidium in t h e brachial valve, a n d in lacking the m a r g i n a l ridge a n d the numerous short brachial trails often so conspicuous on Kozlowskia. Its spine a r r a n g e m e n t is similar to t h a t of Liosotella Cooper, b u t it lacks the strong costae of t h a t genus.

Sestropoma cribriferum C o o p e r a n d Grant, n e w species

Prorichthofenia species Newell, et al., 1953, pi. 21: fig. 33.

A b o u t m e d i u m size for a richthofeniacean, elongate, conical with a n apex angle of a b o u t 40°. Sur- face smooth b u t with n u m e r o u s thick a t t a c h m e n t spines. Pedicle valve with keeled muscle callosity b u t n o s e p t u m . Brachial valve with scattered nodes in place of endospines.

Measurements in mm length

17.4

luidth thickness height 24.7 37.8 ? holotype

T Y P E S . — H o l o t y p e U S N M 151656b; paratypes 151656a, c-k.

STRATIGRAPHIC OCCURRENCE.—Bell Canyon For- m a t i o n (Hegler Limestone M e m b e r ) .

L O C A L I T Y . — U S N M 731, G u a d a l u p e M o u n t a i n s . REMARKS,—Sestropoma is very m u c h like Hercosestria in the possession of a calcareous net over the cup, b u t the latter has a flattish net a n d possesses a strong bladelike m e d i a n septum.

S u p e r f a m i l y P R O D U C T A C E A Gray, 1 8 4 0 Anemonaria C o o p e r a n d Grant, n e w g e n u s

DIAGNOSIS.—Outline subrectangular, widest at hinge, ears e x t e n d e d ; profile deeply concavo-con-

Anemonaria infiata Cooper a n d Grant, n e w species

Maiginifera snhlaevis R. E. King, 1931 [part], p. 89, pi. 23:

figs. 15a-c, 19 [not figs. 13, 14, 17; fig. 16 uncertain].

Size average for genus; outline subrectangular except for extension of large ears; anterior m a r g i n r o u n d e d a n d only slightly sulcate; surface only weakly costellate, primarily near anterior m a r g i n . Spines in 1 row below each ear, occasionally 1 spine on each ear; spines widely a n d r a n d o m l y scattered on venter and trail.

Pedicle valve interior with flabellate diductor marks a n d elongate a d d u c t o r marks; ear baffles distinct. Brachial valve interior with short cardinal process having b r o a d zygidium a n d narrowly r o u n d e d l o p h i d i u m ; muscle marks a n d brachial ridges indistinct; breviseptum e x t e n d i n g forward only to m i d l e n g t h of a d d u c t o r marks.

T Y P E S . — H o l o t y p e U S N M 153833a; p a r a t y p e U S N M 15.3833b.

L O C A L I T Y . — U S N M 721 u. Glass M o u n t a i n s . R E M A R K S . — T h i s is the only k n o w n species of Ancmonnria; the other specimens a t t r i b u t e d by R.

E. King (1931, pi. 23: figs. 13, 14. 17) to Margini- fera sublaevis now are considered species of Kozlowskia.

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N U M B E R 1

Dasysaria C o o p e r a n d Grant, n e w g e n u s

DIAGNOSIS.—Shell large, widest at h i n g e , ears ex- t e n d e d ; surface finely a n d irregularly semireticulate; spines n u m e r o u s , w i t h thick tuft o n ears a n d posterior m a r g i n , fine spines o n visceral disc a n d trail, b u t absent from b r a c h i a l valve. Pedicle valve i n t e r i o r w i t h a d d u c t o r field moderately thickened;

muscle scars d e n d r i t i c . Brachial valve interior with c a r d i n a l process small, widely trilobate, typically dictyoclostid; lateral ridges a n d b r e v i s e p t u m strong.

TYPE-SPECIES.—Dasysaria undulata Cooper a n d G r a n t , n e w species.

R E M A R K S . — T h e general form of Dasysaria recalls t h a t of its nearest relative, Squamaria M u i r - W o o d a n d Cooper. Dasysaria differs p r i m a r i l y in its entire lack of dorsal spines, b u t also in its finely costellate trail.

Dasysaria undulata C o o p e r a n d Grant, n e w s p e c i e s

Productus hessensis R. E. King 1931 [part], p. 68, pi. 11:

figs. 3, 4.

Productus wolfcampensis R. E. King 1931 [part] p. 74, pi.

16: figs. 4, 5?

Shell large, a b o u t as long as wide, b u t ears extended. O r n a m e n t semireticulate, visceral discs of b o t h valves crossed by strong costellae a n d closely spaced concentric u n d u l a t i o n s ; trails of b o t h valves costellate. H a l t e r o i d spines i n tufts above ears; thin body spines a b u n d a n t o n trail a n d visceral disc;

sulcus shallow o r absent.

Pedicle valve i n t e r i o r with d i d u c t o r marks broadly flabellate; a d d u c t o r marks moderately thickened. Brachial valve interior w i t h cardinal process short b u t wide a n d thick, s u p p o r t e d by secondary m e d i a n ridge connected to breviseptum; a d d u c t o r m a r k s strongly d e n d r i t i c b u t n o t m u c h thickened.

T Y P E S . — H o l o t y p e U S N M 148914.

STRATIGRAPHIC OCCURRENCE.—Hueco F o r m a t i o n . L O C A L I T Y . — U S N M 720a, Sierra D i a b l o .

R E M A R K S . — T h i s species is characterized by its large size, strongly reticulate visceral discs, strong costellae, a n d squarish o u t l i n e . T h e t w o other k n o w n species, Productus wolfcampensis R. E. King

(1931, p a r t only: pi. 16: figs. 1-3, b u t n o t figs. 4-5), a n d Productus welleri R . H . K i n g (1938, p . 273, pi.

39: figs. 5-8), are smaller a n d p r o p o r t i o n a t e l y nar-

rower t h a n t h e q u a d r a t e D. undulata. I n a d d i t i o n , the strong u n d u l a t i o n s o n the visceral discs of b o t h valves are distinctive.

Oncosarina C o o p e r a n d Grant, n e w g e n u s

DIAGNOSIS.—Deeply concavo-convex marginiferid with strongly costate trail, n a r r o w ears, a n d con- centrically wrinkled visceral region; spines scattered, confined to pedicle valve, where they oc- cur on costae a n d o n lateral slopes just p r o x i m a l to the ears. Dorsal valve i n t e r i o r with small c a r d i n a l process; a d d u c t o r scars elongated, elevated; m e d i a n breviseptum short, slender.

TYPE-SPECIES.—Oncosarina spinicostata C o o p e r a n d G r a n t , new species.

REMARKS.—Oncosarina resembles Semicostella M u i r - W o o d a n d Cooper, differing in its m o r e spiny pedicle valve exterior, elevated a d d u c t o r muscle platforms, a n d its short, slender breviseptum. I t also resembles Elliottella Stehli, differing in t h e strongly r o u n d e d profile a n d lack of a sulcus o n the pedicle valve.

Oncosarina spinicostata C o o p e r a n d Grant, n e w s p e c i e s

Marginifera manzanica R. E. King [not Girty] 1931, p. 87, pi. 21: figs. 22-24.

Shell small; o u t l i n e transversely subrectangular,.

hinge w i d t h e q u a l to or greater t h a n m i d w i d t h , sides nearly straight; ears small. Profile concavo- convex with d e e p visceral cavity; costae variable;

concentric wrinkles indistinct o n b o t h valves;

spines halteroid, with 1 row along posterior margin, 1 row on each ear, a cluster o n posterolateral slopes, scattered spines o n venter.

Pedicle valve interior w i t h low a d d u c t o r muscle platform a n d r u d i m e n t a r y ear baffles. Brachial valve interior with a d d u c t o r platform of 2 laterally tilted plates separated by breviseptum; c a r d i n a l process small a n d bilobed i n juveniles, thick a n d trilobed in adults; ear baffles high, c o n t i n u i n g a r o u n d anterior as indistinct m a r g i n a l ridge.

STRATIGRAPHIC OCCURRENCE.—Skinner R a n c h For- m a t i o n (Decie R a n c h , P o p l a r T a n k , a n d Sullivan Peak M e m b e r s ) .

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L O C A L I T Y . — H o l o t y p e : U S N M 707ha, Glass M o u n t a i n s .

R E M A R K S . — T h i s species is smaller t h a n the other k n o w n species of the genus, Marginifera? whitei R.

E. King (1931), a n d has less uniform costae a n d m u c h less distinct concentric wrinkling of b o t h valves.

Thamnosia C o o p e r a n d Grant, n e w g e n u s DIAGNOSIS.—Shell deeply piano- to concavo-convex; pedicle valve deep; brachial valve with sharply geniculated trail; hinge wide, ears extended;

surface costellate, visceral discs of b o t h valves con- centrically wrinkled. Spines n u m e r o u s , small on ears; thick brush of spines on posterolateral slopes over ears; m a n y spines on trail; brachial valve with fine hairlike spines.

Pedicle valve interior with ear baffles a n d widely flabellate d i d u c t o r scars not enclosing adductors.

Brachial valve interior with cardinal process bilobed in juveniles, becoming thick a n d trilobed in adults, u n i t e d to weak breviseptum by long slender buttress.

TYPE-SPECIES.—Thamnosia anterospinosa Cooper a n d G r a n t , new species.

R E M A R K S . — T h i s genus most nearly resembles Kutorginella Ivanova (1951), of which Retaria M u i r - W o o d a n d C o o p e r is a j u n i o r synonym, differing in possession of a thick brush of spines on the lateral slopes, a n d n u m e r o u s spines on the trail, whereas Kutorginella has b u t a single row of spines on the lateral slopes and widely scattered spines elsewhere.

Thamnosia anterospinosa C o o p e r a n d Grant, n e w species

Shell o u t l i n e rectangular, hinge w i d t h as great or greater t h a n m i d w i d t h ; cross section plano-convex;

b o t h valves costellate a n d spinose; visceral disc of pedicle valve slightly rugose on lateral slopes a n d just p r o x i m a l to ears; costellae more p r o m i n e n t on visceral disc, flatter on trail, separated by fine striae. T h i c k brush of strong spines on lateral slopes; spines on visceral disc short, fine, widely

scattered; long strong spines concentrated on anterior of trail; spines o n brachial valve thin, short.

Pedicle valve i n t e r i o r with a d d u c t o r field slightly elevated a n d elongated; ear baffles absent. Brachial valve interior with r o u n d e d cardinal buttress elevated a n d c o n t i n u o u s with long breviseptum; cardinal process elongate, strongly trilobed in a d u l t ; ear baffles present, c o n t i n u o u s a r o u n d anterior as mar- ginal ridge; a d d u c t o r muscle field large, lateral scars strongly dendritic.

STRATIGRAPHIC OCCURRENCE—Cathedral M o u n t a i n F o r m a t i o n .

L O C A L I T Y . — U S N M 702un, Glass M o u n t a i n s . R E M A R K S . — T h e most distinctive features of T.

anterospinosa are its relatively large size, a n d numerous strong spines a r o u n d the anterior, culminat- ing in a thick brush of long strong spines on the

posterolateral slopes, with few spines elsewhere. I t differs from Alexenia} parvispinosa Stehli (1954) (herein assigned to Thamnosia) in its m u c h longer a n d thicker spines. Thamnosia parvispinosa has many spines, b u t they are short a n d delicate.

S u p e r f a m i l y LYTTONIACEA W a a g e n , 1 8 8 3

Petasmaia C o o p e r a n d Grant, n e w g e n u s DIAGNOSIS.—Large, flattish, e x p a n d i n g lyttoniaceans having well-developed d e n t a l plates. Com- monly m u c h narrowed at the rear because of habit- ual, a l t h o u g h not universal, a t t a c h m e n t to crinoid stems; consequently, usually has a posteriorly di- rected posterior flap. Differs from Eolyttonia in absence of a h o o d a n d in presence of d e n t a l plates.

TYPE-SPECIES.—Petasmaia expansa Cooper a n d G r a n t , new species.

Petasmaia expansa C o o p e r a n d Grant, n e w species

Large, usually n a r r o w e d posteriorly b u t r a p i d l y a n d widely e x p a n d e d medially; m a x i m u m w i d t h variable b u t usually near midvalve. Exterior smooth. I n t e r i o r of pedicle valve with deep lateral grooves b o u n d e d by strong, thin, high loops di- rected anteriorly. Brachial valve with bilobed cardinal process a n d twelve or m o r e lateral lobes.

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N U M B E R 1 11 Measurements in mm

length

holotype 71.0 paratype 151341a 85.9

maxi- mum width 65.4 83.8

hinge width 10.6

12.9

thick- ness 5.1

?

sides with steep slopes. Interior as defined for the genus.

TYPES—Holotype USNM 151343; paratypes USNM 151341a-g.

STRATIGRAPHIC OCCURRENCE.—Cathedral Moun- tain Formation.

LOCALITY.—USNM 702un, 702b, Glass Moun- tains.

REMARKS.—Petasmaia is readily recognized by its narrowed posterior and is distinguished from other lyttoniaceans in the Glass Mountains (except Cosci- nophora) by the presence of the dental plates and the strong, oblique loops. It differs from Coscino- phora, which also has dental plates, in not having beaded loops.

Superfamily RHYNCHONELLACEA Gray, 1848 Amphipella Cooper and Grant, new genus

DIAGNOSIS.—Small rhynchellacean with smooth exterior and retimarginate anterior commissure.

Delthyrium open. Posterior with 3 foramina, the lateral 2 leading into interior shelly pouches. Den- tal plates short; hinge plate divided. Crura short.

Unlike any other known rhynchonellacean in the presence of the shelly pouches.

TYPE-SPECIES.—Amphipella arcaria Cooper and Grant, new species.

Amphipella arcaria Cooper and Grant, new species

Small, subpentagonal in outline, subequally biconvex in outline; widest near midvalve; sides nearly straight, anterior truncated to faintly emar- ginate, beak forming an angle of 108°. Beak straight to suberect; postero- and anterolateral extremities narrowly rounded. Surface smooth.

Ventral valve gently convex with narrow umbonal region, broadly flattened median region and slightly depressed anterior region that forms a weak sulcus. Brachial valve swollen umbonally, flattened medially and depressed to gently sulcate anteriorly;

brachial

valve hinge thick- length length width width ness holotype 3.8 3.7 4.0 2.0 2.2 TYPES.—Holotype USNM 148098a; paratypes 148098b-z, a'-d'.

STRATIGRAPHIC OCCURRENCE.—Base of Cathedral Mountain Formation.

LOCALITY.—USNM 708u, Glass Mountains.

Bryorhynchus Cooper and Grant, new genus DIAGNOSIS.—Similar to Leiorhynchus Hall and Leiorhynchoidea Cloud externally but differs from the former in its low, often obsolete median ridge and strongly denticulate sockets. The low median ridge distinguishes it also from Leiorhynchoidea as do its divided hinge plate and crural cavity.

TYPE-SPECIES.—Camarophoria} bisulcata Shu- mard (1858, p. 296).

TYPES.—Neotype (selected because Shumard's types were destroyed by fire), USNM 118558

(figured by Girty, 1909, pi. 21: figs, lla-c).

STRATIGRAPHIC OCCURRENCE.—Bell Canyon For- mation.

LOCALITY.—USGS 2930, Guadalupe Mountains.

Divaricosta Cooper and Grant, new genus

DIAGNOSIS.—Small, uniplicate; fold low; costae increasing anteriorly by intercalation and bifurcation. Pedicle valve beak short, blunt; delthyrium nearly completely closed by large deltidial plates;

brachial valve more strongly convex than the ventral one. Pedicle valve interior with vertical dental plates, fused to valve sides by secondary shell in some species. Brachial valve interior with large undivided hinge plate; no median septum, just a rather thick median ridge bisecting muscle area;

crura gently curved, not twisted,

TYPE-SPECIES.—Divaricosta squarrosa Cooper and Grant, new species.

REMARKS.—The intercalated and bifurcated costae resemble those of Fascicosta Stehli (1955),

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which was based on the species Rhynchonella'? lon- gaeva Girty (1909) from the C a p i t a n Limestone.

Stehli's specimens a n d others from the Getaway Limestone M e m b e r of the Cherry C a n y o n Forma- tion, however, are not the same as Girty's specimens. Because Stehli chose Girty's species as

the type, it remains the basis for the genus Fasci- costa, a n d the n a m e Divaricosta is herein i n t r o d u c e d for t h e Getaway species that differs from F. lon- gaeva in the generic characters of large a n d con- j u n c t deltidial plates, u n d i v i d e d hinge plate, a n d merely a low m e d i a n ridge r a t h e r t h a n a well-defined m e d i a n s e p t u m in the brachial valve.

Divaricosta squarrosa Cooper and Grant, n e w species

Fascicosta longaeva Stehli [not Girty] 1955, p. 71, 73, figs.

1-17.

O u t l i n e b l u n t l y subtrigonal to s u b p e n t a g o n a l ; u n i p l i c a t e commissure with low fold b e g i n n i n g in- conspicuously. Costae strong, narrow, ropelike, be- g i n n i n g at beaks, n u m b e r i n g 3-5 on fold, 6-9 on each flank at anterior of adults, having increased from few at beaks by intercalation a n d bifurcation.

Pedicle valve beak short, slightly a t t e n u a t e ; delthy- r i u m wide, nearly completely closed by large, thick, conjunct deltidial plates, leaving small subapical foramen; brachial valve moderately convex, with slightly flattened or i n d e n t e d u m b o n a l region.

Pedicle valve interior with strong tusklike hinge teeth c o n t i n u o u s with nearly vertical d e n t a l plates.

Brachial valve interior with hinge plate large, semi- circular, undivided, b o u n d e d laterally by deep, wide, strongly corrugated hinge sockets leaving h i g h thin outer socket ridges; crural bases vertical, e x t e n d i n g as keels along underside of hinge plate;

m e d i a n ridge thick, r o u n d e d , e x t e n d i n g one-fourth to one-fifth length of valve.

T Y P E S . — H o l o t y p e A M N H 27904:1; hypotype U S N M 148221.

STRATIGRAPHIC OCCURRENCE.—Cherry C a n y o n For- m a t i o n (Getaway Limestone M e m b e r ) .

L O C A L I T Y . — A M N H 512 ( = U S N M 7 2 8 ) , Dela- ware M o u n t a i n s , T e x a s .

REMARKS.—Divaricosta squarrosa is the only established species of the genus a l t h o u g h a n o t h e r remains to be described.

Petasmatherus C o o p e r a n d Grant, n e w g e n u s DIAGNOSIS.—Small to m i n u t e , costate, straight- hinged rhynchonellids with a well-developed interarea on the pedicle valve a n d short crura. Ex- ternally suggests Allorhynchus, b u t t h a t genus lacks the interarea a n d wide hinge.

Petasmatherus opulus C o o p e r a n d Grant, n e w species

Small, flatly biconvex, s u b t r i a n g u l a r in outline;

apex variable b u t averaging a b o u t 90°; gently uniplicate with low fold a n d shallow sulcus; costae strong, 3 to 4 on the fold, 3 or 4 on the flanks. Ped- icle valve interior with small teeth, short d e n t a l plates. Brachial valve interior with divided h i n g e plate a n d short slightly divergent crura; m e d i a n septum absent, b u t low m e d i a n r i d g e present.

length holotype 5.8 148305b 5.8

width 4.9 4.7

brachial valve length

5.9 5.4

hinge width 2.9 2.5

thickness 3.6 3.1 T Y P E S . — H o l o t y p e U S N M 148305a; paratypes 148305b-f.

STRATIGRAPHIC OCCURRENCE.—Word F o r m a t i o n (between Willis R a n c h a n d A p p e l ^ R a n c h Mem- bers) .

L O C A L I T Y . — U S N M 706b, Glass M o u n t a i n s .

REMARKS.—Resembles Pugnax? pusilla Girty (1909), which belongs to the genus Petasmatherus, in general form b u t is m u c h larger a n d m o r e strongly costate.

Phrenophoria C o o p e r a n d Grant, n e w g e n u s DIAGNOSIS.—Exterior suggestive of a coarse-ribbed Leiorhynchus or Leiorhynchoidea. Brachial valve interior with u n d i v i d e d hinge plate s u p p o r t e d by a long t h i n m e d i a n septum, u n l i k e the above-named genera, which have a divided hinge plate.

TYPE-SPECIES.—Phrenophoria subcarinata Cooper a n d G r a n t , new species.

1 When adopted in 1965 by the U.S. Geological Survey, this name was incorrectly spelled "Apple."

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N U M B E R 1 13 Phrenophoria subcarinata C o o p e r a n d Grant,

n e w s p e c i e s

Large, biconvex, t h e brachial valve more strongly convex; u n i p l i c a t e ; beak suberect; foramen small;

deltidial plates conjunct. Valves semicostate, t h e posterior smooth b u t t h e a n t e r i o r m a r k e d by strong r o u n d e d costae.

Pedicle valve s u b c a r i n a t e posteriorly b u t forming a shallow sulcus occupied by 3 costae anteriorly.

Costae adjacent to sulcus low; flanks m a r k e d by 3 costae. T o n g u e long, broad, a n d serrate at its e n d . Brachial valve strongly swollen b u t flattened to faintly sulcate in t h e posterior third. Fold low, flattened, poorly defined.

Pedicle valve interior with strong d e n t a l plates;

d i d u c t o r scars a n t e r i o r to delthyrial c h a m b e r . Brachial valve interior with i n n e r hinge plates u n i t e d ; socket ridges low, m e d i a n s e p t u m support- ing hinge plate t h i n , delicate a n d high, reaching to midvalve.

holotype 148385a

length 17.3 13.00

brachial valve length

15.6 11.1

maximum width

18.7 11.1

thickness 14.2

9.4 T Y P E S . — H o l o t y p e U S N M 148385e; paratypes U S N M 148385a-d, f-i.

STRATIGRAPHIC OCCURRENCE.—Word F o r m a t i o n (between Willis R a n c h a n d A p p e l R a n c h Mem- bers) .

L O C A L I T Y . — U S N M 706b, Glass M o u n t a i n s .

R E M A R K S . — T h i s species suggests "Pugnax"

pinguis Girty, which belongs t o Phrenophoria, b u t differs in its greater convexity, larger size, less p r o m i n e n t fold a n d sulcus, a n d stronger costae.

Pontisia C o o p e r a n d Grant, n e w g e n u s

DIAGNOSIS.—Shell small, semicostate, uniplicate, w i t h d e n t a l plates a n d conjunct deltidial plates in pedicle valve. Brachial valve interior with u n d i - vided h i n g e p l a t e b u t n o m e d i a n s e p t u m . Exter- nally like Wellerella D u n b a r a n d C o n d r a a n d Tautosia Cooper a n d G r a n t (described below) b u t lacking m e d i a n s e p t u m .

TYPE-SPECIES.—Pontisia stehlii Cooper a n d G r a n t , n e w species.

R E M A R K S . — E x t e r n a l l y a n d in t h e pedicle valve this genus resembles Wellerella, b u t t h e b r a c h i a l valve has f u n d a m e n t a l differences. Pontisia has t h e inner hinge plate completely u n s u p p o r t e d , w i t h n o trace of a m e d i a n s e p t u m (only a low r i d g e t h r o u g h the muscle a r e a ) . I n gerontic adults t h e ridge is a u g m e n t e d by secondary shell m a t e r i a l to form a boss b e n e a t h t h e hinge plate, b u t this is n o t high e n o u g h to b e mistaken for a true s e p t u m . Its differences from Tautosia are in the absence of a m e d i a n s e p t u m in the brachial valve a n d i n some external features such as its weaker costae a n d its normally depressed m e d i a n costa of the fold.

Pontisia stehlii C o o p e r a n d Grant, n e w s p e c i e s

Pugnoides texanus R. E. King, 1931 [not Shumard] p. 108, pi. 34: figs. 5-9.

Pugnoides elegans R. E. King, 1931 [part; not Girty] p. 106, pi. 33: figs. 12, 13; pi. 34: fig. 4 [not pi. 34: figs. 2, 3].

Shell average size for genus, b u t r a t h e r b u l b o u s , with the brachial valve deeper a n d m o r e strongly convex t h a n t h e pedicle valve; o u t l i n e transversely trigonal to nearly oval. Fold low, b e g i n n i n g anterior to flattened u m b o n a l area; sulcus strongly convex in profile, b e g i n n i n g anterior t o inflated beak;

costae strong a n d sharp, normally 3 o n fold, 2-6 o n each flank. Valve margins a b r u p t l y flexed to produce a d u l t thickening.

Pedicle valve interior with widely t r i a n g u l a r delthyrium, elongate teeth, vertical d e n t a l plates; muscle marks distinct. Brachial valve i n t e r i o r w i t h t r i a n g u l a r hinge plate u n d i v i d e d b u t deeply notched; crura anteriorly divergent, ventrally curved, a n d strongly twisted with c a r i n a t e dorsal edges. Muscle area bisected by low m e d i a n ridge.

T Y P E S . — H o l o t y p e U S N M 153835a.

STRATIGRAPHIC OCCURRENCE.—Road C a n y o n For- m a t i o n .

L O C A L I T Y . — U S N M 702c, Glass M o u n t a i n s . R E M A R K S . — T h i s species is characterized primarily by its strongly convex brachial valve, b r o a d b u t closely crowded costae, smooth beaks a n d u m b o n a l regions. T h r e e previously p u b l i s h e d species are as-

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signed to Pontisia: Pugnoides mesicostalis Girty (1909), Camerophoria swalloviana Shumard (1859)

(but not the species called "Pugnax" or "Pug-

noides" swalloviana by R. E. King, 1931, or Hall and Clarke, 1894), and Wellerella nanas Stehli

(1954).

Pontisia stehlii differs from P. mesicostalis (Girty) in its smaller size, more bulbous shape, and fewer, broader costae. It differs from P. swalloviana

(Shumard) in its inflated or flattened (not de- pressed) umbonal regions, stronger costae, and internally by its well-developed dental plates. It is larger than P. nanas (Stehli), is transverse rather than anteriorly narrowed, and lacks the depressed median costa of the fold.

Strigirhynchia Cooper and Grant, new genus DIAGNOSIS. — Medium-sized rhynchonellaceans,

uniplicate with costae covering entire surface, with strong dental plates and complete hinge plate sup- ported by a high median septum. In the latter respect it is unlike Allorhynchus Weller, which it resembles externally. Dorsal valve with depressed to concave umbo.

TYPE-SPECIES.—Rhynchonella? indentata Shum- ard (1859, p. 393) ; Girty (1909, p. 321, pi. 15: figs.

20a-c).

TYPES.—Neotype USNM 118572.

STRATIGRAPHIC OCCURRENCE.—^Capitan

Limestone.

LOCALITY.—USGS 2926, Guadalupe Mountains.

Tautosia Cooper and Grant, new genus

DIAGNOSIS.—Small, semicostate, uniplicate, with costae strong at anterior. Pedicle valve interior with strong dental plates; brachial valve interior with complete hinge plate supported by strong median septum.

TYPE-SPECIES,—Tautosia fastigiata Cooper and Grant, new species.

REMARKS.—This genus resembles Wellerella Dun- bar and Condra externally, but differs in its strong median septum in the brachial valve. T h e new genus Phrenophoria (described above) also retains a high median septum, but Tautosia is distin- guished by its angularly costate anterior and its ex- ternal resemblance to Wellerella, whereas Phreno- phoria more nearly resembles Leiorhynchus ex- ternally.

Tautosia fastigiata Cooper and Grant, new species

Large for genus, outline transversely triangular;

fold high, terminating abruptly at anterior; sulcus deep, beginning farther forward than fold. Costae strong, angular, normally numbering about 5 on fold, 5-7 on each flank, with nearly concordant crests. Pedicle valve beak elongate, may have low median crest, sharp beak ridges; foramen mesothy- rid; apex of brachial valve curved beneath deltidial plates of pedicle beak.

Pedicle valve interior with strong dental plates;

muscle area beginning anterior to dental plates.

Brachial valve interior with undivided hinge plate bounded by deep, elongated, corrugated hinge sock- ets; crura strongly curved but only slightly twisted;

median septum high, with muscle area beginning on floor about midway along septum.

TYPES.—Holotype USNM 148345f.

STRATIGRAPHIC OCCURRENCE.—Cathedral

Moun- tain Formation.

LOCALITY.—USNM 702b, Glass Mountains.

REMARKS.—Three other species are assigned to Tautosia. The first is Pugnax elegans Girty (1909) (but not Pugnoides elegans of R. E. King, 1931, nor Wellerella elegans of Stehli, 1954). Tautosia fastigiata differs from Girty's P. elegans in its stronger costae, of which the median one in the fold is not depressed. It differs from T. magnisepta

(Stehli) in its larger size, more transverse outline-, stronger and more numerous costae, and lack of a depressed median costa. It is distinguished from T.

shumardiana (Girty) (not R. E. King) in its costae that are everywhere stronger, and strikingly more numerous on the flanks, and its convex rather than flattened brachial umbonal area.

Superfamily SPIRIFERACEA King, 1 8 4 6 Lepidospirifer Cooper and Grant, new genus

DIAGNOSIS.—Most nearly resembling Neospirifer

Frederiks, but with costellae only weakly fasciculate

and much finer; raised growth laminae on crests of

costellae give a tiled-roof appearance. T h e pedicle

valve beak is relatively straight, with a well-de-

veloped apical plate and a high internal myoph-

ragm.

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N U M B E R 1 15 TYPE-SPECIES.—Lepidospirifer angulatus Cooper

and Grant, new species.

REMARKS.—The tiled-roof appearance of the raised growth laminae also is seen on some species

of Neospirifer; it is not, in itself, the diagnostic dif- ference between the genera, which is the multicostellate exterior. This feature is, however, more con- sistent in species of Lepidospirifer and covers the entire shell in some. In others the scaly raised laminae begin farther forward, possibly having been re- moved by abrasion of the posterior parts of the shell.

Lepidospirifer angulatus Cooper and Grant, new species

Spirifer (Neospirifer) costella R. E. King, 1931 [part], p. 115, pi. 37: fig. 1, 2.

Shell transverse, with rounded hinge extremities;

widest just anterior to hinge. Costellae fine, numbering about 7 in 5 mm, bundled sporadically into indistinct fascicles that tend to die out anteriorly;

raised growth laminae present over most of shell.

Both valves deep, fold and sulcus beginning at beaks; sulcus extended at anterior to form long tongue extending into strongly angular fold at margin.

Pedicle valve interior with small teeth and broad dental ridges supported by short dental plates; my- ophragm extending to near midvalve; muscle marks weakly impressed. Brachial valve interior with strong socket ridges, small cardinal process, and broad concave hinge plate.

TYPES.—Holotype USNM 152940.

STRATIGRAPHIC OCCURRENCE.—Cathedral Moun- tain Formation.

LOCALITY.—USNM 702, Glass Mountains.

REMARKS.—This species is characterized by its proportionately great width, strongly convex valves that produce a thick shell, and its strongly angular fold. It differs from L. costellus (R. E. King) in its greater width, absence of strong fascicles and plications on the flanks, and by its rather strong curvature at the anterior that amounts nearly to a genic- ulation of the valves, especially of the anterior tongue of the sulcus.

Superfamily SPIRIFERINACEA Davidson, 1 8 8 4

Sarganostega Cooper and Grant, new genus DIAGNOSIS.—Shell small, conical, very strongly punctate; punctae expanding toward exterior, re- ducing shell to mere network, effectively obscuring most growth laminae. Fold transversely rounded, with convex profile, lateral plications low and rounded. Pedicle valve interior with high median septum typical of spiriferinaceans, apical end bur- ied in a secondary shell, anterior edge concave forward; dental plates short.

TYPE-SPECIES.—Sarganostega transversalis Cooper and Grant, new species.

REMARKS.—Sarganostega is characterized primarily by its very coarse external punctation, coarser than any known genus excepting only i?ecf?cw/flrnna Fredericks. It differs from Reticulariina in its normally smaller size and more conical shape, lack of exospines, and in its reduced dental plates. Punctae of Recticulariina may be as large as those of Sargan- ostega, but as the shell normally is larger, the pro- portional size of punctae is less in Recticulariina.

Sarganostega tranvsersalis Cooper and Grant, new species

Shell wide for genus, widest at hinge, with hinge ends mucronate; fold high but rounded; sulcus narrow, with flat floor, extending far forward to fill high crest of fold at margin. Lateral costae low, weakening distally, numbering 2 or 3 on each side;

growth laminae obscure, widely and irregularly spaced. Pedicle valve only moderately convex, but beak rather strongly hooked; brachial valve more strongly convex longitudinally.

Pedicle valve interior with weak dental ridges, dental plates discrete and somewhat divergent;

brachial valve interior with hinge sockets roofed by thin plates, cardinal process bulbous, striated.

TYPES.—Holotype USNM 153172.

STRATIGRAPHIC OCCURRENCE.—Bell Canyon For- mation (Pinery Limestone Member).

LOCALITY.—USNM 725n, Guadalupe Mountains.

REMARKS.—The only other published species that belongs to Sargonostega is Spiriferina pyra- midalis Girty (1909, p. 378, pi. 14: figs. 20, 21) from the Capitan Formation. Sarganostega transversalis