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Home , Baca Formation, Bridger Formation, Espinaso Formation, Galisteo Formation

The biostratigraphy of

SPENCER G. LUCAS ) Department of Geology and Geophysics and Peabody Museum of Natural History, Yale University, ROBERT M. SCHOCH / P.O. Box 6666, New Haven, Connecticut 06511 EARL MANNING 108 West 80th Street, New York, New York 10024 COSTAS TSENTAS Department of Anthropology, New York University, New York, New York 10003

ABSTRACT Of these, only the Baca, Galisteo, and San this 16.5-m.y. interval includes the later part Jose Formations have produced vertebrate of the Clarkforkian land mammal "age", the The San Jose, Galisteo, and Baca that demonstrate that part of their entire , Bridgerian, Uintan, and Formations are continental deposits in New included strata are of Eocene age. An Duchesnean land mammal "ages," and the Mexico containing Eocene vertebrate fos- Eocene age was assigned to the other forma- earlier part of the Chadronian land mam- sils. The Almagre and Largo local faunas of tions on the basis of structural context, stra- mal "age" (Berggren and others, 1978; the in the- San Juan tigraphic position, lithology, and radio- McKenna and others, 1973; Rose, 1980). basin are Lysitean (middle Wasatchian). metric dates. Because our concern is with The Clarkforkian land mammal "age" The Cerrillos local fauna of the Galisteo biostratigraphy, we do not further discuss straddles the -Eocene boundary Formation also is Wasatchian, possibly these largely unfossiliferous formations; (Rose, 1980). No vertebrate fossils of Clark- Lysitean. Strata of the Baca Formation in instead, we concentrate on determining the forkian age are known from New Mexico south-central New Mexico contain the ti- ages of the fossiliferous parts of the Baca, (Tsentas and Lucas, 1980). The beginning of tanotheres sp. and cf. Man- Galisteo, and San Jose Formations and Wasatchian time in western North America teoceras sp. and are the only Bridgerian their correlation with recognized subdivi- is recognized biostratigraphically by the strata known in New Mexico. The Tonque sions of the Eocene elsewhere in western first occurrence of perissodactyls, artiodac- local fauna of the and North America. tyls, adapid and omomyid primates, and vertebrates from the Baca Formation To achieve these goals, we (1) briefly dis- hyaenodontid deltatheridians, among others in west-central New Mexico are correlatives cuss and define (when necessary) the subdi- (Rose, 1980). Vertebrate fossils of Wasat- of the Lapoint (Utah), Pearson Ranch visions of the Eocene used here; (2) review chian age occur in New Mexico in the San (California), and Porvenir (Texas) local the stratigraphy and vertebrate faunas of Jose and Galisteo Formations. faunas and are Duchesnean. the Baca, Galisteo, and San Jose Forma- Subdivision of the Wasatchian land Precise placement of the Paleocene- tions and discuss their age; (3) summarize mammal "age" has had a long history. Eocene and Eocene- boundaries the remaining biostratigraphic problems in Three traditional and informal "subages," in New Mexico using vertebrate biostrati- the New Mexico Eocene; and (4) present a the Graybullian (early), Lysitean (middle), graphy is impossible because of a lack of correlation chart of the vertebrate fossil- and Lostcabinian (late), are based largely fossils at critical horizons. The near absence bearing strata of the New Mexico Eocene. on the taxon range zones of the tapiroid of Bridgerian and total absence of Uintan Part II of this paper is an annotated biblio- perissodactyls (presumably fossils in New Mexico may result from a graphy of references on the stratigraphy and Graybullian) and Heptodon (presumably lack of collecting, particularly in parts of paleontology of the New Mexico Eocene, Lysitean and Lostcabinian) and the palaeo- the Baca Formation. including references consulted in the prepa- there Lambdotherium (presumably Lost- ration of this paper but not cited here. cabinian) (Sinclair and Granger, 1911). INTRODUCTION Subsequent studies have revealed a much BIOSTRATIGRAPHIC SUBDIVISION more complex picture of Wasatchian bio- The Eocene , nearly 17 m.y. of OF THE EOCENE IN WESTERN stratigraphy (Schankler, 1980); in our opin- earth history, is well represented by conti- NORTH AMERICA ion, no clearly defined and readily usable nental deposits and vertebrate fossils in subdivision of the Wasatchian yet exists. New Mexico. Formations in New Mexico We consider the Eocene Epoch to include Schankler's (1980) range-zone biostratig- that have been assigned an Eocene age are the interval from approximately 53.5 m.y. raphy of the Wasatchian in the Bighorn the Baca, Blanco Basin, Cub Mountain, El B.P. to approximately 37 m.y. B.P. Basin, is the most explicit and Rito, Espinaso, Galisteo, Love Ranch, (Berggren and others, 1978; Hardenbol and useful attempt to subdivide the Wasatchian McRae, Orejon, Palm Park, and San Jose. Berggren, 1978). In western North America, biostratigraphically. However, outside of

This article is based on a paper presented at a symposium entitled "Cenozoic Continental Deposits and Fossils of New Mexico," held in April 1981.

Supplementary data for this article appear in Part II of the Bulletin, v. 92, no. 12, p. 2268-2307.

Geological Society of America Bulletin, Part I, v. 92, p. 951-967, 11 figs., 3 tables, December 1981.

951

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the Bighorn Basin, the absence of taxa criti- importance here. Briefly, the Bridgerian has into North America of ruminants (Simi- cal to Schankler's (1980) biostratigraphy been defined by the presence of typical meryx and Hendryomeryx), true entelo- and unresolved taxonomic problems lessen Bridgerian taxa such as Palaeosycps, donts (Brachyhyops), large rhinos (Tri- the utility of Schankler's subdivisions when Homacodon, , Helaletes, and gonias and/or Subhyracodon), and large attempting correlation with the faunas of "advanced" paramyids and by the absence hyaenodonts (Pterodon, Hyaenodon, and the San Jose Formation in New Mexico. (presumed extinction) of typical Wasat- Hemipsalodori) (Golz, 1976; Mellett, 1977; Although we here use Schankler's (1980, chian taxa such as , Hyracoth- Webb, 1977; but see Black, 1978, for a dif- Fig. 1) subdivision of the Wasatchian into erium, and Pelycodus (Gazin, 1976; ferent view of ruminant origins). The ratio- the Gray Bull biostratigraphic zone Gingerich, 1979; Guthrie, 1971; West, nale behind defining land mammal "age" (= Haplomylus-Ectocion range zone plus 1973a; Wood and others, 1941). Compara- boundaries by immigration events has been Bunophorus interval zone), Lysite biostra- ble criteria and the first appearance of amy- discussed and, in our opinion, justified by tigraphic zone (= lower and middle Hep- nodont rhinocerotoids by immigration from Repenning (1967). The evolutionary first todon range zone), and Lostcabin bio- Asia mark the beginning of the Uintan occurrence of Teleodus, Mesohippus, and stratigraphic zone (= upper Heptodon range (Black and Dawson, 1966; Wood and oth- Poabromylus also help to define the Uintan- zone), we also rely on comparisons with the ers, 1941). Duchesnean boundary. "type" Lysite Member and Lostcabin Tedford (1970, p. 690-692) and Wilson The Duchesnean-Chadronian boundary Member faunas of the Wind River Basin, (1978, p. 33-37) have reviewed the history of is defined by the immigration into North Wyoming (Guthrie, 1967, 1971) for faunal the differing views of the validity of the America of a number of taxa, including the characterization of these time intervals. Duchesnean land mammal "age." We here anthracothere Bothriodon, the carnivores Very few fossils of Bridgerian age and follow Tedford (1970) and Golz (1976), con- Musielavus, Palaeogale, Hoptophoneus, none that we consider of Uintan age are tra Wilson (1978) and Emry (1981), in rec- and Parictis and the manid Patriomanis, known in New Mexico, and so the biostra- ognizing the Duchesnean to be a distinct although admittedly most of these taxa are tigraphic recognition and subdivision of land mammal "age." We define the Uintan- rare (Emry, 1970; Simpson, 1947). The these land mammal "ages" is not of great Duchesnean boundary by the immigration Duchesnean land mammal "age" is character-

Figure 1. Outcrops of the San Jose Formation, San Juan basin, northwestern New Mexico: A. Strata of the Regina Member in the type area of the San Jose Formation, NW'/S, sec. 29, T. 2*3 N., R. 1 W. El. Strata of the Tapicitos Member in the headlands of Oso Canyon,

NW'/4, sec. 30, T. 25 N., R. 1 W. C. Strata of the Regina Member in the headlands of Gobernador Canyon, SW'/4, sec. 26, T. 29 N., R. 5 W.

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¡zed by the Lapoint fauna of the Duchesne imately equals the Almagre "beds" or was by Granger (1915) and Matthew River Formation, Uinta Basin, Utah, which "facies" of Granger (1914) and Simpson (1915a, 1915b, 1915c, 1918). Van Houten is the "type" fauna of the Duchesnean as (1948); it also includes the lower part of (1945) gave the most recent list of San Jose defined by Wood and others (1941), and its their Largo. The Llaves Member (as much vertebrates. correlatives. The best studied correlatives of as 400 m thick) primarily consists of coarse- Granger (1914) recognized two distinct the Lapoint are the Pearson Ranch local grained and conglomeratic, arkosic sand- faunas in the San Jose, Almagre and Largo, fauna, Sespe Formation, California (Golz, stone and lesser amounts of red and corresponding to the "beds" to which he 1976; Golz and Lillegraven, 1977) and the variegated mudstone. It either overlies the assigned these names. The Regina Member Porvenir local fauna, Chambers Tuff, Texas Cuba Mesa or Regina Members, or it south and east of the continental divide (Wilson, 1978). grades into and intertongues with the Reg- produced Granger's (1914) Almagre fauna ina Member. The Tapicitos Member (90 to as well as part of his Largo fauna (Fig. 3). SAN JOSE FORMATION 150 m thick), the uppermost member of the The Tapicitos Member west of the conti- San Jose Formation, primarily consists of nental divide produced much of Granger's Previous Studies maroon mudstone and lesser amounts of (1914) Largo fauna (Fig. 3). The two faunas lenticular, coarse-grained sandstone. It thus are essentially from separate, localized Simpson (1948, 1951, 1981) and Lucas either overlies or grades laterally into the areas and are positively from different strati- (1977) summarized the history of previous Llaves Member and includes most of the graphic horizons. We thus refer to them as studies of the San Jose Formation. Impor- Largo "beds" or "facies" of Granger (1914) the Almagre and Largo local faunas, follow- tant references on the stratigraphy and and Simpson (1948). ing Taylor's (I960, p. 10) definition of a paleontology of the San Jose Formation local fauna as an "assemblage from one not cited here are listed in Part II of this Vertebrate fauna locality, or from several localities, which are paper. [sic] demonstrably stratigraphically equiv- The diverse vertebrate fauna of the San alent or nearly so." Stratigraphy Jose Formation includes , a frog, tur- At present, the biostratigraphic resolu- tles, lizards, a snake, crocodilians, a bird, tion attainable within the San Jose Forma- Simpson (1948) first named the San Jose and mammals (Table 1). The last revision of tion is no better than the recognition of the Formation ("Wasatch" of early workers) for a major portion of the San Jose vertebrates Almagre and Largo local faunas. Although exposures along and near the continental divide, 1.6 km northwest of Regina (sec. 29, T. 23 N., R. 1 W.) in the east-central San Juan basin (Figs. 1A, 2, 3). Outcrops of the San Jose Formation are developed in the central and eastern portions of the San Juan basin (Fig. 2). Granger (1914) first divided the unit later named the San Jose Formation into the Almagre (lower) and Largo (upper) "beds." The variegated mudstones of Granger's (1914) "Almagre beds" are principally ex- posed south and east of the continental divide near Llaves and Regina (Fig. 3). The red mudstones of Granger's (1914) "Largo beds" are principally exposed in Oso Canyon and Gavilan Creek, west of the con- tinental divide near Gavilan and Lindrith (Fig. 3). Simpson (1948) recognized the Almagre and Largo as clay facies and also distinguished an unnamed basal sandstone facies of the San Jose Formation. Baltz (1967) formally defined four mem- bers of the San Jose Formation and mapped their distribution throughout much of the east-central San Juan basin (Fig. 4). The Cuba Mesa Member (60 to 240 m thick) primarily consists of coarse-grained and conglomeratic, arkosic sandstone. It approximately equals Simpson's (1948) un- named basal sandstone facies. The overly- ing Regina Member (150 to 460 m thick) consists of drab-colored, variegated mud- Figure 2. Distribution of the San Jose Formation (stippled) in the San Juan basin, stone and interbedded sandstone. It approx- northwestern New Mexico (after Dane and Bachman, 1965).

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/92/12/951/3430070/i0016-7606-92-12-951.pdf by guest on 01 October 2021 Figure 3. Distribution of members of the San Jose Formation and major fossil-vertebrate localities of the Almagre and Largo local faunas in the Regina-Lindrith area (see Fig. 2 for location). Geology modified from Baltz (1967); localities from Simpson (1948) and unpublished data.

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Figure 4. Diagrammatic cross section from near Regina (SE) to south of Gobernador (NW), showing stratigraphic relation- ships of the Cuba Mesa, Regina, Llaves, and Tapicitos Members of the San Jose Formation (Baltz, 1967) and the approximate stratigraphic position of vertebrate-fossil locali- ties of the Almagre (A) and Largo (L) local faunas and Gober- ó^o O.O .OVO nador (G) area localities.

Also, all Coryphodon of the Almagre and Largo local faunas possess biolophodont

M3's, a form typical of many post- Graybullian Coryphodon. Thus, we are cer- tain that all, or most, of the horizons that it may be possible to further subdivide these Simpson's more recent field collections are produced the Almagre and Largo faunas local faunas and recognize that they include obtainable, but our work along these lines is are post-Graybullian. within them horizons of distinctly different still in progress. Thus, it is impossible at Nevertheless, several taxa in the Almagre ages, we lack sufficient data to subdivide present to determine the precise stratigraph- local fauna (examples are Esthonyx bisulca- them. ic range of many taxa within the San Jose tus, Oxyaena forcipata, Didymictis p. Recently discovered fossil vertebrates in Formation. (3) The lack of temporally protenus, Uintacyon m. massetericus, Para- the Regina Member near Gobernador (Fig. diagnostic nonequid perissodactyls in the mys excavatus, and Phenacodus brachypter- 1C), 60 to 70 km northwest of Regina (Fig. Almagre and Largo local faunas (Van nus) do occur in Graybullian horizons in 2), include: gars, crocodilians, turtles, Houten, 1945). Homogalax is present in the Wyoming, as well as in Lysitean and/or Oxyaena sp., Ectoganus gliriformis gliri- Almagre local fauna (Froehlich and Reser, Lostcabinian horizons (Bown, 1979, 1980; formis, Esthonyx bisulcatus, 1981) but does not shed any light on the Schankler, 1980; West, 1973a). Some or all miliculus, Phenacodus primaevus, Hyra- problem of correlation with subdivisions of specimens of these taxa may derive from a cotherium sp., Coryphodon sp., and Micro- the Wasatchian, because it ranges from the Graybullian horizon, or horizons, in the syops sp. (Kues and others, 1977). Although Gray Bull through Lostcabin biostrati- San Jose Formation. If so, part of the these taxa are present in the Almagre local graphic zones (Bown, 1979, 1980; Guthrie, Regina Member may be Graybullian in age. fauna, further stratigraphic work and more- 1971; Radinsky, 1963; Schankler, 1980). Lacking stratigraphic evidence to support diverse collections will be needed to decide In view of these problems, it is not sur- this possibility, we assign a Lysitean age to whether these fossils belong to the Almagre prising that different workers have come to the Almagre local fauna for the following local fauna or in a new local fauna. different conclusions as to the age of the Almagre and Largo local faunas. Granger 1. It includes the taxa Pelycodus frugiv- Age (1914) believed the Almagre to be of orus and hians. These taxa Graybullian-Lysitean age and the Largo are present in the Lysite Member of the The joint occurrence of Hyracotherium, to be of Lysitean-Lostcabinian age. Wind River basin (Guthrie, 1967) and Coryphodon, Hyopsodus, Paramys, Micro- Van Houten (1945) and Simpson (1948) apparently are restricted to Lysitean hori- syops, Pelycodus, Oxyaena, Didymictis, considered the Almagre to be of Graybul- zons in the Bighorn basin (Bown, 1979, and Meniscotherium indicates that both the lian age and the Largo to be of Lysitean age. 1980; Schankler, 1980). We thus tentatively Almagre and Largo local faunas are of Gingerich and Simons (1977) suggested, on consider these taxa to be Lysitean "index" Wasatchian age (Wood and others, 1941). the basis of the adapid primates, that the fossils. Correlation of the Almagre and Largo local Almagre and Largo local faunas are Lost- 2. The Almagre local fauna lacks genera faunas with the Gray Bull, Lysite, and Lost- cabinian in age. Lucas (1977) and Froehlich that first appear during the Lostcabinian in cabin biostratigraphic zones of the Wasatch- and Reser (1981) also considered the Al- Wyoming, including Lambdotherium, Sty- ian is more difficult due to three major magre and Largo local faunas to be of Lost- linodon, and (Guthrie, 1971; problems: (I) The lack of a clearcut and cabinian age. However, we here argue that Schankler, 1980; Schoch, 1981). This argues usable biostratigraphic subdivision of the the Almagre and Largo local faunas are of against assigning a Lostcabinian age to the Wasatchian discussed earlier. Schankler's Lysitean age, although the possibility can- Almagre. (1980) biostratigraphic subdivision of the not be excluded that older and younger 3. The taxa Prodiacodon tauricinerei, Bighorn basin Wasatchian is a good step in horizons are also represented. Didelphodus absarokae, Oxyaena the right direction; but, for the reasons Taxa such as Pelycodus frugivorus, forcipata, Phenacodus brachypternus, and noted above, it is difficult to apply outside Copeiemur consortutus, Meniscotherium Chriacus gallinae are not known from the of the Bighorn basin. (2) The lack of precise chamense, and Xenicohippus sp. in the Lostcabinian of the Wind River and Big- stratigraphic data for the important early Almagre and Largo local faunas indicate a horn basins (Guthrie, 1967; Schankler, collections in the San Jose Formation made post-Graybullian (Lysitean or Lost- 1980). Their presence in the Almagre local by Cope, Baldwin, Wortman, and Granger cabinian) age (Bown and Kihm, 1981; fauna also suggests that it is not Lost- (Lucas, 1977). Precise stratigraphic data for Gazin, 1965; Gingerich and Simons, 1977). cabinian in age. Ectoganus gliriformis gliri-

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Taxa Types Local launa Last revision/Source

Class OSTEICHTHYES Family LEPISOSTEIDAE Atractosteus simplex (Leidy, 1873) A, L Wiley (1976) Class AMPHIBIA Anuran, indeterminate A AMNH(R) 7277 Class REPTILIA Order TESTUDINES Family BAEN1DAE IBaena arenosa Leidy, 1870 Gaffney (1972) Family KaiHstira costilata (Cope, 1875) Hay (1908) Family Echmatemys cibollensis (Cope, 1877) A? Hay (1908) E. lativertebralis (Cope, 1877) Hay (1908) Family TESTUDINIDAE 7 Geochelone (Manouria) majuscuta (Hay, 1904) Auffenberg (1974) Family A? Amyda cariosa (Cope, 1875) Hay (1908) A? A. radula (Cope, 1875) A? Hay (1908) A. Iventricosa (Cope, 1877) ? Hay (1908) Plastomenus calenatus Cope, 1875 A? Hay (1908) P. communis Cope, 1875 A? Hay (1908) P. corrugatus Cope, 1875 A? Hay (1908) P. Ifractus Cope, 1875 A? Hay (1908) P. Ilachrymalis Cope, 1874 9 Hay (1908) ? P. Veptomitus (Cope, 1875) Hay (1908) Platypeltis serialis (Cope, 1877) 9 Hay (1908) Order SQUAMATA Family Paraglyptosaurus yatkolai Sullivan, 1979 A Sullivan (1979) Family sp. A, L AMNH(R) specimens Order OPHIDIA Family cf. Helagras sp. AMNH(R) 7266 Order CROCODILIA Family CROCODYLIDAE chamensis (Cope, 1874) Cope (1877) C. grypus (Cope, 1875) Cope (1877) C. wheeleri (Cope, 1875) Cope (1877) C. leliiotii (Leidy, 1873) Cope (1877) C. lliodon (Marsh, 1871) Cope (1877) Orthosaurus sphenops (Cope, 1875) Cope (1877) Class AVES Family DIATRYMIDAE Dialryma gigamea Cope, 1876 Shufeldt (1913) Class MAMMALIA Order MARSUPIALIA Family DIDELPHIDAE Peratherium comstockfl Cope, 1885 AMNH 48762 Order EDENTATA Family METACHEIROMYIDAE ?Palaeanodon sp. AMNH 16765 Order DELTATHERIDIA Family "PALAEORYCTIDAE" Didelphodus absarokae (Cope, 1881) Van Valen (1966) Family Prololomus viverrinus Cope, 1874 ? Van Valen (1965) P. mullicuspis Cope, 1875 9 Van Valen (1965) P. 'hecundarius Cope, 1875 9 Van Valen (1965) Triiemnodon slrenua (Cope, 1875) 9 Van Valen (1965) T. hians (Cope, 1877) A Van Valen (1965) Family atavus Matthew, 1915 ? Denison (1938) Oxyaena lupina Cope, 1874 A, L Denison (1938) O. forcipala Cope, 1874 A Denison (1938) O. simpsoni Van Valen, 1966 L Van Valen (1966) Ambloctonus sinosus Cope, 1875 c; L? Denison (1938) A. hyaenoides Matthew, 1915 L Denison (1938)

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Taxa Types Local fauna Last revision/Source

Order Family "MIAC1DAE" Oodectes sp. A AMNH specimens Uintacyon m. massetericus (Cope, 1882) A AMNH specimens Vulpavus ausiratis Matthew, 1915 S A, L Matthew (1915a) cf. M. parvivorus Cope, 1872 A AMNH specimens Didymictis p. protenus (Cope, 1874) G A, L AMNH specimens Order TAENIODONTA . Family STYLINODONTIDAE Ectoganus g. gliriformis Cope, 1874 A, L Schoch (1981) Order TILLODONTIA Family ESTHONYCHIDAE .Esthonyx bisulcatus Cope, 1874 A, L Gingerich & Gunnell (1979) Order PANTODONTA Family CORYPHODONTIDAE Coryphodon radians (Cope, 1872) A Osborn (1898) C. armatus (Cope, 1872) A, L Osborn (1898) C. elephantopus (Cope, 1874) A Osborn (1898) C. cuspidatus (Cope, 1875) A Osborn (1898) C. latidens (Cope, 1875) A Osborn (1898) C. lobatus Cope, 1877 A Osborn (1898) C. testis (Cope, 1882) A Osborn (1898) Order lNSECTIVORA sensu stricto Family ADAP1SORIC1DAE Scenopagus curtidens (Matthew, 1909) 7 Robinson (1968), Krishtalka (1976a) Diacodon allicuspis Cope, 1875 A Krishtalka (1976a) Macrocranion nitens (Matthew, 1918) A Krishtalka (1976a) Family NYCTITHERI1DAE Leptacodon catulus Krishtalka, 1976 A Krishtalka (1976b) Nyctitherium serotinum (Marsh, 1872) 9 Krishtalka (1976b) Order INSECTIVORA sensu lato Family APATEMYIDAE Apatemys bellus Marsh, 1872 A West (1973b) Family LEPTICTIDAE Prodiacodon tauricinerei (Jepsen, 1930) A Novacek (1977) Family Palaeosinopa didelphoides (Cope, 1881) A AMNH 16239 Family APHELISCIDAE Apheliscus insidiosus (Cope, 1874) 7 Cope (1877) Order PRIMATES sensu stricto Family ADAP1DAE Pelycodus frugivorus Cope, 1875 S A, L Gingerich & Simons (1977) P. jarrovii (Cope, 1874) G A Gingerich & Simons (1977) Copelemur tutus(Cope, 1877) G A, L Gingerich & Simons (1977) C. co«ioríuíuí.Gingerich & Simons, 1977 9 Gingerich & Simons (1977) Family Uintanius vespertinus (Matthew, 1915) Szalay (1976) Order PRIMATES sensu lato Family PAROMOMYIDAE Phenacolemur jepseni Simpson, 1955 Szalay & Delson (1979) Family MICROSYOPIDAE wilsoni Szalay, 1969 ? Szalay (1969) M. angustidens (Matthew, 1915) L Szalay (1969) M. latidens (Cope, 1882) A, L Szalay (1969) Navajovius mckennai Szalay, 1969 A Szalay (1969) Order RODENTIA Family PARAMYIDAE Paramys c. copei Loomis, 1907 L Wood (1962) P. c. bicuspis (Loomis, 1907) A, L Wood (1962) P. excavatus taurus Wood, 1962 A Wood (1962) aff. Leptotomus costitto Wood, 1962 A Wood (1962) Thisbemys nini Wood, 1962 L Wood (1962) Franimys buccatus (Cope, 1877) 9 Wood (1962) Order "CONDYLARTHRA" Family ARCTOCYONIDAE Chriacus gallinae Matthew, 1915 A Matthew (1915a) A nacodon ursidens Cope, 1882 A AMNH 16224 Thryptacodon australis Simpson, 1935 A AMNH 48571

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TABLE I. (Continued)

Taxa Types Local fauna Last revision/Source

Family HYOPSODONTIDAE Hyopsodus miticulus (Cope, 1874) A, L ? Gazin ( 1968) H. wortmanP. Osborn, 1902 Gazin (1968) Family MESONYCH1DAE Pachyaena ossifraga Cope, 1874 Cope (1877) Family PHENACODONTIDAE Phenacodus primaevus Cope, 1873. A West (1976) P. brachypternus Cope, 1882 A, L West (1976) P. vortmani (Cope, 1880) A West (1976) Family MENISCOTHER1IDAE Meniscotherium chamense Cope, 1874 G A, L Gazin (1965) M. lapiacitum Cope, 1882 S L Gazin (1965) Order PERISSODACTYLA Family Hyracotherium index (Cope, 1873) A Gingerich, pers. comm. H. vasacciense (Cope, 1872) A, L Gingerich, pers. comm. H. tapirinum (Cope, 1875) A, L Gingerich, pers. comm. Xenicohippus sp. A, L Bown & Kihm (1981) Family ISECTOLOPH1DAE Homogalax protapirinus (Wortman, 1896) A Froehlich & Reser (1981) cf. H. protapirinus (Wortman, 1896) A Froehlich & Reser (1981) Order ARTIODACTYLA Family D1CHOBUNIDAE Diacodexis chacensis (Cope, 1875) A, L Sinclair (1914) D. cf. D. secans (Cope, 1881) A Sinclair (1914) Bunophorus dorseyanus (Sinclair, 1914) A Sinclair (1914) B. granger; (Sinclair, 1914) A, L Sinclair (1914)

Note: AMNH and AMNH(R) are specimens in the fossil mammal and fossil collections of the American Museum of Natural History, New York. G = type of genus from the San Jose Formation; S = type of species from the San Jose Formation; A = Almagre local fauna; L = Largo local fauna.

formis occurs only in Graybullian and cotherium tapiaciturn are present in the from very' few specimens in the Largo, and Lysitean horizons (Schoch, 1981); its pres- Largo local fauna but absent in the Alma- their absence in the Almagre may result ence in the Almagre local fauna further gre. Meniscotherium tapiaciturn, Oxyaena from sampling and /or preservational biases supports a pre-Lostcabinian age as- simpsoni, Ambloctonus hyaenoides, Ambbctonus (Lucas, 1977). Paramys copei copei and signment. sinosus, and Thisbemys nini are known Microsyops angustidens are so small that 4. The typical Graybullian genera Plagio- mene, Ectocion, and Haplomylus are not present in the Almagre local fauna. Their absence lends support to assigning a post- Graybullian age to the Almagre local fauna. The Lysitean is recognized biostrati- graphically more by the absence of taxa than by the presence of taxa whose distribu- tion is limited to that interval. This forces a heavy reliance on negative evidence (absen- ces) in arguing for a Lysitean age for any fauna, and thus weakens such arguments. Recognizing this weakness and acknowledg- ing the need for further stratigraphic and taxonomic studies, we believe it is most reasonable at present to consider the Alma- gre local fauna to be of Lysitean age. The Largo local fauna is largely a taxo- nomically depauperate subset of the Al- magre local fauna (Table 1; Lucas, 1977). Only the mammals Oxyaena simpsoni, Ambloctonus hyaenoides, Ambloctonus sinosus, Microsyops angustidens, Paramys copei copei, Thisbemys nini, and Menis-

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their absence in the Almagre also could be EAST the result of inadequate sampling. Because the Largo local fauna shares most of its taxa with the Almagre, we believe that they are not of significantly dif- ferent ages, although stratigraphic evidence indicates that the Largo is younger than the • UPPER YELLOW Almagre. Of the mammalian taxa restricted PEBBLY SS- to the Largo, Ambloctonus hyaenoides only is found in the Lostcabin biostratigraphic zone in the Bighorn basin (Schankler, 1980) and thus might be used as evidence to argue for a Lostcabinian age for the Largo local fauna. However, specimens of Amblocto- nus hyaenoides are so rare that we hesitate to attach much biostratigraphic significance to its uncommon occurrences. The other taxa restricted to the Largo local fauna also do not indicate a Lostcabinian age. We thus agree with Van Houten (1945), Simpson (1948), and Gazin (1965) in assigning the Largo a Lysitean age. Meniscotherium chamense, which is present in the type Lost- 100 M cabinian (Guthrie, 1971), may have its earli- est (Lysitean) occurrence in the Almagre IT TONQUE LOCAL FAUNA and Largo local faunas (Gazin, 1965). I c CERRILLOS LOCAL FAUNA

GALISTEO FORMATION [¿> J[ TUFF »BRECCIA -

Previous Studies CONGLOMERATE

I' SANDSTONE Johnson (1902-03), Stearns (1943), Kelley and Northrop (1975), Lucas and Kues MUOSTONE 4 SILTSTONE (1979), and Lucas (1982) summarized the COAL history of previous studies of the Galisteo

HAGAN

Figure 6. Correlation of fossiliferous out- crops of the Galisteo Formation in the Rio Puerco fault zone (Windmill Hill), Hagan basin (Montoya, Tuerto, Hagan), and Cer- rillos area (after Lucas, 1982). See Lucas (1982) for precise locations of measured sections.

Formation. Important references on the stratigraphy and paleontology of the Galis- teo Formation ,not cited here are listed in Part II of this paper.

Stratigraphy

Hayden (1869, p. 1.66-167) first named the "variegated sands and sandstones" along the Galisteo Creek .east of Cerrillos the "Gallrsteo [sic], sand .group." It is evident from Hayden's (1869) description that the north-central New Mexico (after Lucas, 1982). type area of the Galisteo Formation is in

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TABLE 2. LIST OF FOSSIL VERTEBRATE TAXA FROM THE CERRILLOS AND fully documented the distribution and com- TONQUE LOCAL FAUNAS, GALISTEO FORMATION, position of these local faunas. The Cerrillos NORTH-CENTRAL NEW MEXICO local fauna (Table 2) is a small assemblage of mammals and lower vertebrates found in Taxa Cerrillos local fauna Tonque local fauna an interval 369 to 429 m above the base of the Galisteo Formation in its type section Class OSTEICHTHYES Family LEPISOSTEIDAE east of Cerrillos (Lucas, 1981, 1982). The Genus indeterminate X Tonque local fauna (Table 2) is a small Class REPTILIA group of assemblages dominated by titano- Order TESTUDINES there remains, principally of Teleodus. Fos- Family TRIONYCHIDAE sils of the Tonque local fauna are found in Genus indeterminate X X Family INDETERMINATE X the upper part of the Galisteo Formation Class MAMMALIA east of Cerrillos, in the Hagan basin, and in Order DELTATHERIDIA the Rio Puerco fault zone (Lucas, 1982). Family HYAENODONTIDAE The stratigraphic distribution of the Pterodon sp. X Tonque local fauna supports Lucas' (1982) Order TAENIODONTA Family STYLINODONTIDAE correlation of fossiliferous Galisteo out- Ectoganus sp. X crops based on Gorham's (1979) "upper yel- Order PANTODONTA low pebbly sandstone member" (Fig. 6). Family CORYPHODONTIDAE Coryphodon sp. X Order PRIMATES sensu lato Age Family MICROSYOPIDAE Microsyops sp. X The joint occurrence of Ectoganus sp., Order RODENTIA Family PARAMYIDAE Coryphodon sp., Microsyops sp., Hyopsodus Genus indeterminate X powellianus, cf. Homogalax protapirinus, Order "CONDYLARTHRA" and Hyracotherium sp. indicates that the Family HYOPSODONTIDAE Cerrillos local fauna is of Wasatchian age Hyopsodus powellianus. Cope, 1884 X (Wood and others, 1941). Hyopsodus Order PERISSODACTYLA Family powellianus is a post-Graybullian form cf. Homogalax protapirinus (Wortman, 1896) X (Gazin, 1968; Gingerich, 1974; Schankler, Family EQUIDAE 1980) and thus provides slight evidence that Hyracotherium sp. X the Cerrillos local fauna is Lysitean or Lost- Family cabinian. The presence of Ectoganus in the Teleodus cf. T. uintensis Peterson, 1919 X Genus indeterminate X Cerrillos local fauna, on the other hand, Family suggests that it is of Graybullian or Lysitean Amynodon sp. X age (Schoch, 1981). However, the Cerrillos Family Forstercooperia minuta Lucas, Schoch and. X Manning, 1981 Order ARTIODACTYLA Family AGRIOCHERIDAE Protoreodon sp. X Family PROTOCERATIDAE Poabromylus cf. P. minor Wilson, 1974 X Genus indeterminate X

Note: data from Lucas, 1982.

sections 14, 15, 16, 21, 22, and 23, T. 14 N., Ingersoll (1979) recognized seven informal R. 8 E. (Lucas, 1982). Lucas (1982) defined members of the formation in the Hagan an 1,100-m-thick section of the Galisteo basin. Lucas (1982) recognized Gorham's Formation in this area as the type section of "upper yellow pebbly sandstone member" in the formation. Stratigraphic studies and the Rio Puerco fault zone and Cerrillos area mapping, principally by Stearns (1943) and and used it to correlate fossiliferous out- subsequent workers, have demonstrated crops of the Galisteo Formation (Fig. 6). that the Galisteo Formation is well devel- oped in north-central New Mexico, both Vertebrate Fauna east and west of the Rio Grande (Fig. 5). No formal stratigraphic subdivision of the Gali- In a preliminary study, Lucas and Kues steo Formation has been proposed, al- (1979) recognized two local faunas in the though Gorham (1979) and Gorham and Galisteo Formation. Lucas (1982) more

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local fauna is so small an assemblage (nine ers (1981) have summarized previous stu- reported occurrences are of biostratigraphic mammal specimens) that its precise correla- dies of the Baca Formation. Important significance: (1.) Gardner (1910, p. 454) tion within the Wasatchian must await references on the stratigraphy and paleon- reported a tooth identified by J. W. Gidley further discoveries. tology of the Baca Formation not cited here as "possibly Palaeosyops" from the lower Lucas and Kues (1979) and Lucas (1982) are listed in Part II of this paper. part of the Baca Formation east of the Rio tentatively considered the Tonque local Grande near Carthage. However, the speci- fauna to be of Duchesnean age. They based Stratigraphy men was not described or illustrated, and this correlation largely on the presence in we have been unable to locate it. (2.) Snyder the Tonque local fauna of Teleodus and Wilpolt and others (1946) named the lower (1970, 1971) illustrated a maxillary frag- Poabromylus, mammals whose evolution- 208 m of Winchester's (1920) Datil Forma- ment found 37.5 m above the base of ary first occurrence is in the Duchesnean. tion the Baca Formation. The type locality the Baca Formation west of the Rio Grande The presence of Amynodon in the Tonque of the Baca Formation is in Baca Canyon near Datil. C. L. Gazin identified this local fauna, however, suggests it may be of (sections 4, 5, 8, and 9, T. 1 N„ R. 4 W.), specimen as cf. Protoreodon pumilus (Sny- Uintan age. Definite assignment of the western Socorro County, New Mexico. der, 1971). Schrodt (1980) identified the Tonque local fauna to the Duchesnean is Discontinuous outcrops of the Baca Forma- same specimen as Protoreodon pumilus. difficult because, other than Pterodon, the tion trend east-west in an approximately 16- (3) Cather (1980) reported an artiodactyl Tonque local fauna lacks immigrant taxa km-wide band in Socorro and Catron trackway in the lower part of the Baca distinctive of Duchesnean time. Because the Counties, New Mexico. They also extend Formation near Magdalena. This trackway Tonque local fauna is so small (about 100 into eastern Arizona (Fig. 7; Snyder, 1971). appears to represent three individuals, of mammal specimens, mostly titanotheres Wilpolt and others (1946) and Wilpolt and different sizes, of the same type of large from a single quarry), it is difficult to Wanek (1951), among others, have des- artiodactyl. The tracks are parallel, appear determine whether the absence of these cribed and mapped Baca Formation out- to proceed in the same direction and may immigrant taxa is chronologically signifi- crops east of the Rio Grande in the vicinity represent a group of individuals traveling cant or merely reflects a lack of adequate of the Joyita Hills and Carthage. The Baca together. (4.) Lucas and others (1981) de- sampling. Therefore, although we tenta- Formation has not been formally subdi- scribed and illustrated teeth of cf. Manteoce- tively consider the Tonque local fauna to be vided, although various workers have rec- ras sp. from essentially the same locality as of Duchesnean age, we emphasize that it is ognized informal subdivisions in local areas Gardner's (1910) supposed Palaeosyops oc- late Eocene regardless of its more precise (Cather, 1980; Potter, 1970; Snyder, 1971). currence in the Baca Formation near Car- biostratigraphic age. Neither a comprehensive stratigraphic anal- thage. (5.) Schiebout and Schrodt (1981) ysis nor a stratigraphic correlation of all the reported Leptomeryx from the White Mesa BACA FORMATION outcrops mapped as Baca Formation exists. area (= the Protoreodon locality of Snyder, 1970, 1971). (6.) Schiebout and Schrodt Previous Studies Vertebrate Fauna (1981) also recorded a small mammalian fauna from the vicinity of Mariano Mesa, Snyder (1971), Johnson (1978), Cather Very few vertebrate fossils are known north of Quemado, New Mexico (Fig. 7; Table 3). (1980), Schrodt (1980), and Lucas and oth- from the Baca Formation, and only six

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TABLE 3. LIST OF FOSSIL VERTEBRATE TAXA FROM THE BACA FORMATION, shale, siltstone, and sandstone of the Naci- SOUTH- AND WEST-CENTRAL NEW MEXICO miento Formation (Fig. 9). Locally, as much as 10 m of the Taxa Carthage White Mesa Mariano Mesa apparently were removed by erosion during the deposition of the overlying Cuba Mesa Class MAMMALIA Order DELTATHERIDIA Member, and scour-and-fill plus local angu- Family HYAENODONTIDAE lar discordance at the Nacimiento Forma- IHyaenodon sp. X tion-Cuba Mesa Member contact (Fig. Order PERISSODACTYLA 10C) characterize this unconformity. Family BRONTOTHERIIDAE cf. Manleoceras sp. X The stratigraphically lowest fossil mam- Palaeosyops sp. X mals in the San Jose Formation are from "Menodus" sp. the Regina Member, at least 60 m above the Order ARTIODACTYLA San Jose-Nacimiento contact, and are Family ENEYLODONTIDAE X Wasatchian in age. The stratigraphically Brachyhyops wyomingensis Colbert, 1938 Family AGRIOCHERIDAE highest Paleocene mammal occurrence in Protoreodon pumilus (Marsh, 1875) X Torreon Wash ("Pantolambda zone", Fig. Family PROTOCERATIDAE 9) is of middle Paleocene (Torrejonian) age Leplomeryx sp. X and is about 30 m below the San Jose- Family CAMELIDAE Nacimiento contact. There is thus a lack of Eotylopus sp. X fossil representation from Torrejonian to X Wasatchian, a gap of at least 7 m.y. (Har- Note: Taxa from the White Mesa area from Snyder (1970) and Schiebout and Schrodt (1981); taxa denbol and Berggren, 1978). Therefore, the from Mariano Mesa from Schiebout and Schrodt (1981). Taxa from the Carthage area from Gardner (1910) and Lucas and others (1981). Paleocene-Eocene boundary in the south- central San Juan Basin is located some- Age by detailed stratigraphic documentation of where in the upper part of the Nacimiento new and old localities. However, where this Formation or the lower part of the San Jose Both Palaeosyops and Manleoceras are is possible, some problems may never be Formation (Tsentas and Lucas, 1980) Bridgerian titanotheres (Osborn, 1929). The resolved because of a lack of fossiliferous trackway reported by Cather (1980) indi- strata in critical areas or at critical horizons. Wasatchian cates that part of the Baca Formation is late Eocene or younger. All fossil-vertebrate Paleocene-Eocene Boundary Further resolution of the precise correla- taxa from the Mariano Mesa and White tion of the Almagre and Largo local faunas Mesa areas also occur in the Porvenir local The Paleocene-Eocene transition in New of the San Jose Formation with the bio- fauna in Texas (Schiebout and Schrodt, Mexico is not well documented by sedi- stratigraphic subdivisions of the Wasatchian 1981; Wilson, 1978). Schiebout and Schrodt ments and fossils. Most formations that largely depends on detailed documentation (1981) therefore believed the Mariano Mesa contain Eocene fossils (Baca, Galisteo) and of the stratigraphic ranges of taxa with- and White Mesa area vertebrates to be cor- some of those of presumed Eocene age (for in the San Jose Formation. Similar cor- relatives of the Porvenir local fauna. We a- example, El Rito, Cub Mountain) uncon- relation of the Cerrillos local fauna of the gree with this correlation, but differ from formably overlie Upper (Man- Galisteo Formation requires more diverse them in calling the Porvenir local fauna cos Shale, Mesaveirde Group) or older collections than those presently available. Duchesnean, instead of Chadronian in age Mesozoic rocks (for example Morrison (see earlier discussion). Palynological evi- Formation). The San Juan Basin is the only Bridgerian-Uintan dence, though scanty, suggests "that the area in New Mexico where lower Eocene The virtual absence of fossils of Bridger- Baca is certainly at least as young as strata (San Jose Formation) overlie rocks ian and Uintan age in New Mexico may Eocene" (Chaiffetz, 1979, p. 268); it thus with Paleocene fossils (Nacimiento Forma- reflect a need for further collecting, particu- does not contradict the vertebrate fossil tion) (Figs. 8, 9). However, the absence of larly in parts of the Baca Formation. The evidence. Therefore, the fossiliferous out- Clarkforkian fossil vertebrates (Tsentas and absence of Bridgerian and Uintan fossils in crop of the Baca Formation east of the Rio Lucas, 1980) and the presence of an uncon- the Galisteo Formation, however, might Grande is of Bridgerian age, whereas the formity between the San Jose Formation result from an absence of strata of these fossiliferous outcrops of the Baca Forma- and the underlying Nacimiento Formation ages. Significant between tion west of the Rio Grande are significantly (Baltz, 1967) hinder precise biostratigraphic Wasatchian and Duchesnean strata of the younger, being Duchesnean in age. placement of the Paleocene-Eocene boun- Galisteo Formation may represent much or dary even in this area. all of Bridgerian and Uintan time (Lucas, UNRESOLVED PROBLEMS This unconformity is seen readily in the 1982). headlands of Torreon Wash in the south- Introduction central San Juan basin (Figs. 8, 9). Here, Duchesnean coarse-grained and conglomeratic, arkosic Unresolved problems and gaps in our sandstone of the Cuba Mesa Member of the The Tonque local fauna of the Galisteo knowledge of the biostratigraphy of the San Jose Formation (Fig. 10A, B, D) con- Formation and the vertebrates from the New Mexico Eocene can largely be elimi- tains large, prone fossil logs (Fig. 10E) and Mariano Mesa area of the Baca Formation nated by additional collecting, accompanied unconformably overlies interbedded clay are small assemblages that need further

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T21N

SOtL * ALLUVIUM CUBA MESA MEMBER SAN JOSE FORMATION NACIMIENTO FORMATION REGINA MEMBER Figure 8. Geologie map of the headlands of Torreon Wash in the south-central San Juan basin, northwestern New Mexico (see Fig. 2 for location), showing the location of the measured sections in Figure 9 and major Torrejonian fossil-vertebrate localities (after Kues and others, 1977). Geology modified from Baltz, 1967.

faunal characterization to verify their tenta- tive assignment to the Duchesnean. SAN JOSE FRMN. Eocene-Oligocene Boundary unconformity No vertebrate fossils of Oligocene age are known from New Mexico, and so vertebrate biostratigraphic placement of the Eocene- Oligocene boundary is impossible. How- ever, radiometric dates from the Espinaso (overlying the Galisteo Formation) and Spears (overlying the Baca Formation) Formations indicate that these formations are of Oligocene age (S. Cather, 1981, personal commun.; Kautzand others, 1981; Weber and Bassett, 1963) and thus al- low approximate placement of the epoch boundary in parts of New Mexico.

CORRELATION OF THE NEW MEXICO EOCENE

In spite of the many unresolved problems and gaps in our knowledge of the Eocene

Figure 9. Measured sections of the upper part of the Nacimiento Formation and lower part of the Cuba Mesa Member of the San Jose Formation in the headlands of Torreon Wash (see Fig. 8 for location), showing the distinct unconformity separating the two formations. See Tsentas (1981) for descriptions of sections B and F and rationale for correlation of the sections using black clay shales.

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/92/12/951/3430070/i0016-7606-92-12-951.pdf by guest on 01 October 2021 Figure 10. Strata of the Nacimiento Formation-San Jose Formation contact in the headlands of Torreon Wash: A. Coarse-grained and conglomeratic sandstones of the Cuba Mesa Member of the San Jose Formation (TSJ), overlying interbedded sandstones, clay shales, and siltstones of the Nacimiento Formation (TN) on the west flank of Torreon Wash (sections 26-27, T. 21 N., R. 5 W.). B. Crossbedded and grave lly strata of the Cuba Mesa Member in the SEÍ4, sec. 26, T. 21 N., R. 5 W. Rock hammer is 28 cm long. C. Local discordance, scour, and rip-up clasts at the contact between crossbedded sandstones of the Cuba Mesa Member and underlying clay shales and siltstones of the Nacimiento Formation in the SE!4, sec. 26, T. 21 N., R. § W. Rock hammer is 28 cm long. D. Graded bedding at the base of the Cuba Mesa Member in the SE!4, sec. 26, T. 21 N., R. 5 W. Pencil is 18 cm long. E. Prone and abraded fossil log near the base of the Cuba Mesa Member, NEÍ4, sec. 25, T. 21 N., R. 5 W. Rock hammer is 28 cm long.

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Black, C. C., and Dawson, M. R., 1966, A review of late Eocene mammalian faunas from North America: American Journal of Science, v. 264, p. 321-349. Bown, T., 1979, Geology and mammalian paleontology of the Sand Creek facies, lower (lower Eocene), Washakie County, Wyoming: Wyoming Geological Survey Memoir 2, 151 p. 1980, The Willwood Formation (lower Eocene) of the southern Bighorn basin, Wyoming, and its mammalian fauna: Michigan University Papers on Paleontology 24, p. 127-138. Bown, T. M., and Kihm, A. J., 1981, Xeni- cohippus, an unusual new hyracotheriine (Mammalia, Perissodactyla) from lower Eocene rocks of Wyoming, Colorado and New Mexico: Journal of Paleontology, v. 55, p. 257-270. Cather, S. M., 1980, Petrology, diagenesis, and genetic stratigraphy of the Eocene Baca Formation, Alamo Navajo Reservation and vicinity, Socorro County, New Mexico [M.S. thesis]: Austin, Texas, University of Texas, 243 p. Chaiffetz, M. S., 1979, Palynological age and Figure 11. Correlation of the vertebrate-fossil-bearing formations of Eocene age in New paleoecology of the Baca Formation, north- Mexico. Vertebrate faunas (black bars) are: A = Almagre local fauna; CA = Carthage area western Socorro County, central-western New Mexico: Geological Society of America titanotheres; C = Cerrillos local fauna; L = Largo local fauna; M = Mariano Mesa verte- Abstracts with Programs, v. 9, p. 268. brates; T= Tonque local fauna; W = White Mesa vertebrates. Temporal magnitude of Cope, E. D., 1877, Report upon the extinct unconformities (hatched) is diagrammatic. Vertebrata obtained in New Mexico by parties of the expedition of 1874: Geo- biostratigraphy of New Mexico, it is possi- to collect from outcrops under their juris- graphical Surveys West of the One ble to present a reasonably precise correla- diction, we thank R. Peterson, O. Shelton, Hundredth Meridian (Wheeler Survey), part 2, p. 1-370. tion of the fossil-bearing Eocene of the state the owners of the Diamond Tail Ranch, and Dane, C. H„ and Bachman, G. O., 1965, with recognized subdivisions of the Eocene the U.S. Bureau of Land Management. The Geologic map of New Mexico: U.S. Geolog- (Fig. II). Clearly, a rich field for further research reported here was supported by ical Survey, scale 1:500,000. collecting and biostratigraphic study exists National Science Foundation Grant DEB- Denison, R. H., 1938, The broad-skulled in the Eocene of New Mexico, and we hope 7919681 and two Grants-in-Aid of Research Pseudocreodi: New York Academy of Science Annals, v. 37, p. 163-256. that the synthesis presented here will estab- from the Society of Sigma Xi to Lucas, an Emry, R. J., 1970, A North American Oligocene lish the need and provide stimulation for NSF graduate fellowship to Schoch, and and other additions to the Pholi- continuing research in this area. funds for field work provided by the Uni- dota: American Museum of Natural History versity of New Mexico, U.S. Bureau of Bulletin, v. 142, p. 455-510. 1981, Additions to the mammalian fauna of ACKNOWLEDGMENTS Land Management, and Yale University. the type Duchesnean, with comments on the Comments on the manuscript by T. Bown, status of the Duchesnean "age": Journal of Among the numerous people who have B. Kues, J. Schiebout, and R. West have Paleontology, v. 55, p. 563-570. rendered invaluable assistance in the field improved its content and clarity. Froehlich, J. W., and Reser, P. K., 1981, First work upon which much of this paper is occurrence of Homogalax (Mammalia; Perissodactyla; ) in the Regina based, we thank S. Ash, S. Cather, S. Cobb, REFERENCES CITED Member of the San Jose Formation, San E. Devor, D. Froehlich, J. Froehlich, W. Juan Basin, New Mexico, in Lucas, S. G., Gavin, T. Gorham, A. Hunt, B. Kues, M. Auffenberg, W., 1974, Checklist of fossil land Rigby, J. K., Jr., and Kues, B. S„ eds., Leaf, T. Lehman, I. Lucas, R. Lozinsky, M. (Testudinidae): Florida State Mu- Advances in San Juan basin paleontology: seum Bulletin, v. 18, p. 121-251. Albuquerque, New Mexico, University of O'Neill, P. Reser, J. K. Rigby, Jr., R. Sulli- Baltz, E. H., 1967, Stratigraphy and regional New Mexico Press, p. 293-303. van, W. Tidwell, S. Wing, and D. Wolberg. tectonic implications of part of Upper Gaffney, E. S., 1972, The systematics of the E. Baltz spent much appreciated time in the Cretaceous and Tertiary rocks, east-central North American family (Reptilia, field with the senior author explaining the San Juan basin, New Mexico: U.S. Geo- Cryptodira): American Museum of Natural logical Survey Professional Paper 552, stratigraphy of the San Jose Formation. History Bulletin, v. 147, p. 241-320. 101 p. Gardner, J. H„ 1910, The Carthage coal field, For permission to study specimens in their Berggren, W. A., McKenna, M. C., Hardenbol, New Mexico: U.S. Geological Survey Bul- care, we thank R. Emry, B. Kues, E. Lind- J., and Obradovich, J. D„ 1978, Revised letin 381, p. 452-460. say, M. McKenna, J. Ostrom, R. Purdy, P. polarity time scale: Journal of Gazin, C. L., 1965, A study of the Tertiary Robinson, D. Savage, C. Schaff, and R. Geology, v. 86, p. 67-81. condylarthran mammal Meniscolherium: Black, C. C., 1978, Paleontology and geology of Tedford. G. Case, R. Emry, H. Galiano, M. Smithsonian Miscellaneous Collections, v. the Badwater Creek area, central Wyoming. 149, p. 1-98. Hecht, G. Maclntyre, and S. McDowell Part 14. Artiodactyls: Carnegie Museum 1968, A study of the Eocene condylarthran helped identify specimens. For permission Annals, v. 47, p. 223-259. mammal Hvopsodus: Smithsonian Miscel-

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laneous Collections, v. 153, p. 1-90. Publication 75, 568 p. Creodonta: American Museum of Natural 1976, Mammalian faunal zones of the Hayden, F. V., 1869, Preliminary field report of History Bulletin, v. 34, p. 4-103. Bridger middle Eocene: Smithsonian Con- the U.S. Geological Survey of Colorado and 1915b, A revision of the lower Eocene tributions to Paleobiology 26, 25 p. New Mexico: U.S. Geological Survey Third Wasatch and Wind River faunas, Part II. Gingerich, P. D., 1974, Stratigraphic record of Annual Report, 155 p. Order Condylarthra, Family Hyopsodon- early Eocene Hyopsodus and the geometry Johnson, B. D., 1978, Genetic stratigraphy and tidae: American Museum of Natural History of mammalian phylogeny: Nature, v. 253, provenance of the Baca Formation, New Bulletin, v. 34, p. 31 1-328. p. 111-113. Mexico and the Eager Formation, Arizona 1915c, A revision of the lower Eocene 1979, Phylogeny of middle Eocene Adapidae [M.S. thesis]: Austin, Texas, University of Wasatch and Wind River faunas, Part IV. (Mammalia, Primates) in North America: Texas, 150 p. Entelonychia, Primates, Insectívora (part): Smilodecles and : Journal of Johnson, D. W„ 1902-1903, The geology of the American Museum of Natural History Bul- Paleontology, v. 53, p. 153-163. Cerrillos Hills, New Mexico: Columbia Uni- letin, v. 34, p. 429-483. Gingerich, P. D„ and Gunnel!, G. F., 1979, versity School of Mines Quarterly, v. 24, 1918, A revision of the lower Eocene Systematics and evolution of the genus p. 173-246 (part 2, Paleontology), 1902; Wasatch and Wind River faunas, Part Esthonyx (Mammalia, Tillodontia) in the p. 303-350, 456-500 (part 1, General Geol- V. Insectívora (continued), Glires, Eden- early Eocene of North America: University ogy), 1903; v. 25, p. 69-98 (part 3, Petrology), tata: American Museum of Natural History of Michigan Contributions from the Mu- 1903. Bulletin, v. 38, p. 565-657. seum of Paleontology, v. 25, p. 125-153. Kautz, P. F., Ingersoll, R. V., Baldridge, W. S., McKenna, M. C., Russell, D. E., West. R. M., Gingerich, P. D., and Simons, E. L., 1977, Damon, P. E., and Shafiqullah, M„ 1981, Black, C. C., Turnbull, W. D., Dawson, Systematics, phylogeny, and evolution of Geology of the (Oligo- M. R., and Lillegraven, J. A., 1973, K/Ar early Eocene Adapidae (Mammalia, Pri- cene), north-central New Mexico: Geological recalibration of Eocene North American mates) in North America: University of Society of America Bulletin, Part I, v. 92 land-mammal "ages" and European stages: Michigan Contributions from the Museum (this issue). Geological Society of America Abstracts of Paleontology, v. 24, p. 245-279. Kelley, V. C., and Northrop, S. A., 1975, with Programs, v. 5, p. 733. Golz, D. J., 1976, Eocene Artiodactyla of Geology of the Sandia Mountains and Mellett, J. S., 1977, Paleobiology of North southern California: Los Angeles County vicinity, New Mexico: New Mexico Bureau American Hyaenodon (Mammalia, Creo- Natural History Museum Science Bulletin of Mines and Mineral Resources Memoir 29, donta): Contributions to Vertebrate Evolu- 26, 85 p. 136 p. tion, v. 1, p. 1-134. Golz, D. J., and Lillegraven, J. L., 1977, Krishtalka, L., 1976a, Early Tertiary Adapisor- Novacek, M. J., 1977, A review of Paleocene Summary of known occurrences of terrestrial icidae and (Mammalia, Insect- and Eocene Leptictidae (Eutheria, Mamma- vertebrates from Eocene strata of southern ívora) of North America: Carnegie Museum lia) from North America: PaleoBios, v. 24, California: Wyoming University Contribu- of Natural History Bulletin, v. 1, p. 1-40. p. 1-42. tions to Geology, v. 15, p. 43-65. 1976b, North American Osborn, H. F., 1898, Evolution of the Gorham, T. W., 1979, Geology of the Galisteo (Mammalia, Insectívora) of North America: Amblypoda. Part I. Taligrada and Panto- Formation, Hagan basin, New Mexico, Annals of the Carnegie Museum, v. 46, donta: American Museum of Natural [M.S. thesis]: Albuquerque, New Mexico, p. 7-28. History Bulletin, v. 10, p. 169-218. University of New Mexico, 136 p. Kues, B. S., Froehlich, J. W„ Schiebout, J. A., 1929, The titanotheres of ancient Wyoming, Gorham, T. W., and Ingersoll, R. V., 1979, and Lucas, S. G., 1977, Paleontological sur- Dakota and Nebraska: U.S. Geological Evolution of the Eocene Galisteo Basin, vey, resource assessment, and mitigation Survey Monograph 55, v. 1, p. 1-702, v. 2, north-central New Mexico: New Mexico plan for the Bisti-Star Lake area, north- p. 703-953. Geological Society Guidebook 30, p. 219— western New Mexico: U.S. Bureau of Land Potter, S. C., 1970, Geology of the Baca Canyon, 224. Management Unpublished Report, Albu- Socorro County, New Mexico [M.S. thesis]: Granger, W., 1914, On the names of lower querque, New Mexico, 1525 p. Tucson, University of Arizona, 54 p. Eocene faunal horizons of Wyoming and Lucas, S. G., 1977, Vertebrate paleontology of Radinsky, L., 1963, Origin and early evolution of New Mexico: American Museum of Natural the San Jose Formation, east-central San North American Tapiroidea: Yale Peabody • History Bulletin, v. 33, p. 201-207. Juan basin, New Mexico: New Mexico Museum Bulletin 17, 106 p. 1915, A revision of the lower Eocene Geological Society Guidebook 28, p. 221- Repenning, C. A., 1967, Palaearctic-Nearctic Wasatch and Wind River faunas, Part III, 225. mammalian dispersal in the late Cenozoic, in Order Condylarthra, Families Phenacodon- 1981, Recognition, age and extent of Galisteo Hopkins, D. M., ed., The Bering land tidae and Meniscotheriidae: American Mu- Formation .in north-central New Mexico: bridge: Stanford, California, Stanford Uni- seum of Natural History Bulletin, v. 34, American Association of Petroleum Geolo- versity Press, p. 288-314. p. 329-361. gists Bulletin, v. 65, p. 564. Robinson, P., 1968, Nyctitheriidae (Mammalia, Guthrie, D. A., 1967, The mammalian fauna of 1982, Vertebrate paleontology, stratigraphy Insectívora) from the Bridger Formation of the Lysite Member, Wind River Formation and biostratigraphy of the Eocene Galisteo Wyoming: Wyoming University Contribu- (early Eocene) of Wyoming: Southern Cali- Formation, north-central New Mexico: New tions to Geology, v. 7, p. 129-138. fornia Academy of Science Memoirs, v. 5, Mexico Bureau of Mines and Mineral Rose, K. D., 1980, Clarkforkian land-mammal p. 1-53. Resources Circular 186, in press. age: revised definition, zonation, and ten- 1971, The mammalian fauna of the Lost Lucas, S. G., and Kues,.B. S„ 1979, Vertebrate * tative intercontinental correlation: Science, • Cabin Member, Wind River Formation biostratigraphy of the Eocene Galisteo v. 208, p. 744-746. (lower Eocene) of Wyoming: Carnegie Formation, north-central New Mexico: New Schankler, D. M., 1980, Faunal zonation of the Museum Annals, v. 43, p. 47-113. Mexico Geological .Society Guidebook 30, Willwood Formation in the central Bighorn Hardenbol, J., and Berggren, W: A., 19.78, A new p. 225-229. basin, Wyoming: Michigan University Paleogene numerical time scale, in Cahee, Lucas, S. G., Wolberg, D. L., Hunt, A., and Papers on Paleontology 24, p. 99-114. G. V., Glaessner, M. F., and Hedberg, .Schoch, R. M., 1981, A middle Eocene Schiebout, J. A., and Schrodt, A. K., 1981, H. D., eds., Contributions to the geologic titanothere from the Baca Formation, Vertebrate paleontology of the lower Terti- time scale: Tulsa, Oklahoma, American south-central New Mexico: Journal of ary Baca Formation of western New Mexico: Association of Petroleum Geologists, p. Paleontology (in press). Geological Society of American Bulletin, v. 213-234. Matthew, W. D., "1915a, A Devision oLthe lower 92, (this issue). Hay, O. P., 1908, The fossil turtles of North Eocene Wasatch and Wind River faunas, Schoch, R. M., 1981, Taxonomy and biostratig- America: Carnegie Institute of Washington Parti. Order Ferae (Carnivora), Suborder -raphy of the early Tertiary Taeniodonta

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/92/12/951/3430070/i0016-7606-92-12-951.pdf by guest on 01 October 2021 EOCENE BIOSTR ATIGRAPH Y OF NEW MEXICO 967

(Mammalia; Eutheria): Geological Society and the insectivore-primate transition: Bul- paleontology of the New Fork-Big Sandy of America Bulletin, v. 92 (this issue). letin of the American Museum of Natural area, Sublette County, Wyoming: Fieldiana: Schrodt, A. K., 1980, Depositional environments, History, v. 140, p. 193-330. Geology, v. 29, p. 1-193. provenance, and vertebrate paleontology of 1976, Systematics of the Omomyidae 1973b, Review of the North American the Eocene-Oligocene Baca Formation, (Tarsiiformes, Primates): Taxonomy, phyl- Eocene and Oligocene Apatemyidae (Mam- Catron County, New Mexico [M.S. thesis]: ogeny and adaptations: American Museum malia, Insectivora): Texas Technical Univer- Baton Rouge, Louisiana, Louisiana State of Natural History Bulletin, v. 156, sity Museum Special Publications, v. 3, 42 p. University, 174 p. p. 157-450. 1976, The North American Phenacodontidae Shufeldt, R. W„ 1913, Further studies of fossil Szalay, F. S., and Delson, E., 1979, Evolutionary (Mammalia, Condylarthra): Milwaukee birds with descriptions of new and extinct history of the primates: New York, Aca- Public Museum Contributions to Biology species: Bulletin of the American Museum of demic Press, 580 p. and Geology, v. 6, 78 p. Natural History, v. 32, p. 285-306. Taylor, D. W., 1960, Late Cenozoic molluscan Wiley, E. O., 1976, The phylogeny and bio- Simpson, G. G., 1947, Holarctic mammalian faunas from the high plains: U.S. Geological geography of fossil and recent gars (Actin- faunas and continental relationships during Survey Professional Paper 337, 94 p. opterygii: Lepisosteidae): Kansas University the Cenozoic: Geological Society of America Tedford, R. H., 1970, Principles and practices of Miscellaneous Publication 64, III p. Bulletin, v. 58, p. 613-688. mammalian in North Amer- Wilpolt, R. H., MacAlpin, A. J., Bates, R. L., 1948, The Eocene of the San Juan basin, ica: North American Paleontological Con- and Vorpes, G., 1946, Geologic map and New Mexico: American Journal of Science, vention 1969, Proceedings, part F, p. stratigraphic sections of the rocks v. 246, p. 257-282 (part 1) and p. 363-385 666-703. of Joyita Hills, Los Pinos Mountains and (part 2). Tsentas, C., 1981, Mammalian biostratigraphy of northern Chupadera Mesa, Valencia, Tor- 1951, Hayden, Cope, and the Eocene of New the middle Paleocene (Torrejonian) strata of rance and Socorro Counties, New Mexico: Mexico: Academy of Natural Sciences of the San Juan basin: Notes on Torreon Wash U.S. Geological Survey Oil and Gas In- Philadelphia Proceedings, v. 103, p. 1-21. and the status of the Pantolambda and vestigations Preliminary Map 61, scale 1981, History of vertebrate paleontology in Deltatherium faunal "zones," in Lucas, 1:62,500. the San Juan basin, in Lucas, S. G., Rigby, S. G., Rigby, J. K., Jr., and Kues, B. S., eds., Wilpolt, R. H., and Wanek, A. A., 1951, Geology J. K., Jr., and Kues, B. S., eds., Advances in Advances in San Juan Basin paleontology: of the region from Socorro and San Antonio San Juan basin paleontology: Albuquerque, Albuquerque, New Mexico, University of east to Chupadera Mesa, Socorro County, New Mexico, University of New Mexico New Mexico Press, p. 264-292. New Mexico: U.S. Geological Survey Oil Press, p. 3-25. Tsentas, C., and Lucas, S. G., 1980, Position of and Gas Investigations Map OM-121, scale Sinclair, W. J., 1914, A revision of the bunodont the Paleocene-Eocene boundary in the 1:62,500. Artiodactyla of the middle and lower Eocene south-central San Juan Basin, New Mexico: Wilson, J. A., 1978, Stratigraphic occurrence and of North America: American Museum of Geological Society of America Abstracts correlation of early Tertiary vertebrate Natural History Bulletin, v. 33, p. 267-295. with Programs, v. 12, p. 538. faunas Trans-Pecos Texas: Texas Memorial Sinclair, W. J., and Granger, W., 1911, Eocene Van Houten, F. B., 1945, Review of latest Museum Bulletin, v. 25, p. 1-42. and Oligocene of the Wind River and Paleocene and early Eocene mammalian Winchester, D. E., 1920, Geology of Alamosa Bighorn basins: American Museum of faunas: Journal of Paleontology, v. 19, Creek Valley, Socorro County, New Mexico, Natural History Bulletin, v. 30, p. 83-117. p. 421-461. with special reference to the occurrence of oil Snyder, D. O., 1970, Fossil evidence of Eocene Van Valen, L., 1965, Some European Proviverrini and gas: U.S. Geological Survey Bulletin age of Baca Formation, New Mexico: New (Mammalia, Deltatheridia): Palaeontology, 716-A, p. 1-15. Mexico Geological Society Guidebook 21, p. v. 8, p. 638-665. Wood, A. E., 1962, The early Tertiary rodents of 65-67. 1966, Deltatheridia, a new order of mam- the family Paramyidae: American Philo- 1971, Stratigraphic analysis of the Baca mals: Bulletin of the American Museum of sophical Society Transactions, v. 52, 261 p. Formation, west-central New Mexico [Ph.D. Natural History, v. 132, p. 1-126. Wood, H. E„ 2nd, Chaney, R. W„ Clark, J., thesis]: Albuquerque, New Mexico, Univer- Webb, S. D., 1977, A history of savanna Colbert, E. H., Jepsen, G. L., Reeside, J. B., sity of New Mexico, 160 p. vertebrates in the New World. Part 1 : North Jr., and Stock, C., 1941, Nomenclature and Stearns, C. E., 1943, The Galisteo Formation of America: Annual Review of Ecology and correlation of the North American conti- north-central New Mexico: Journal of Systematics, v. 8, p. 355-380. nental Tertiary: Geological Society of Amer- Geology, v. 51, p. 301-319. Weber, R., and Bassett, W., 1963, K-Ar ages of ica Bulletin, v. 52, p. 1-48. Sullivan, R. M., 1979, Revision of the Paleogene Tertiary volcanic and intrusive rocks in genus Glyplosaurus (Reptilia, Anguidae): Socorro, Catron, and Grant Counties, New Bulletin of the American Museum of Natural Mexico: New Mexico Geological Society MANUSCRIPT RECEIVED BY THE SOCIETY History, v. 163, p. 1-72. Guidebook 14, p. 220-224. OCTOBER 1, 1981 Szalay, F. S., 1969, Mixodectidae, Microsyopidae West, R. M., 1973a, Geology and mammalian MANUSCRIPT ACCEPTED OCTOBER 1, 1981

Primed in U.S.A.

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