Myotis velifer in the quitaque local fauna, motley county, Texas.
The unidentified bat specimen consists of a single upper molar (Midwestern State University vertebrate paleontology collection no. 19233--Fig. 1). This specimen initially was examined by Claude Hibbard, who found it to be unlike all North American bats, and who believed it probably belonged to an undescribed species (Dalquest, 1964; Dalquest and Schultz, 1992).
[FIGURE 1 OMITTED]
At the request of W. W. Dalquest, I reexamined this bat tooth. The specimen, a right Ml, is broken in its metastylar area but otherwise is intact. The tooth can be described as follows: ectoloph is typically W-shaped; hypocone is absent but a postprotocrista extends posteriad from the metaconule as a curved sloping ridge with a small talon formed by its base. The trigon basin is deep and is closed off posteriorly by a strong postmetaconule crista (metaloph of Menu, 1985) and anteriorly by a strong postparaconule crista (paraloph of Menu, 1985). The preprotocrista is continuous with a precingulum extending to the parastyle. The lingual cingulum is interrupted on the talon and at the base of the protocone. The posterolingual portion of the cingulum is indented between protocone and talon. The tooth measures 1.90 mm in transverse width (measured from the lingual edge of protocone to the labial edge of tooth at the parastyle) and 1.25 mm in lingual anteroposterior length.
On comparison with all North American species of bats, the specimen is that of a vespertilionid and belongs to Myotis velifer, which it matches in size and details of morphology. The only difference I detected between the fossil and Ml in modern specimens of M. velifer was the indentation of the posterolingual margin between protocone and talon. Although this configuration was not seen in modern specimens, it nevertheless probably fits within the normal individual variation in the species. The size of the fossil matches Ml of M. v. magnamolaris, and the fossil occurrence lies within the modern range of that subspecies.
Myotis velifer is relatively common as a late Pleistocene and Holocene fossil in southwestern North America (Fig. 1, Table 1). Quitaque Creek is the northernmost fossil occurrence of the species. The specimen contributes to an increasing record of the Pleistocene distribution of this species in Texas. In fact, most Pleistocene records of M. velifer have originated in what is now Texas. Perhaps more interesting is the unique occurrence of the Quitaque Creek bat in an open site rather than in a cave like all the other fossil records. Also, all previous fossil records are from caves in regions of limestone or dolomite karst. The Quitaque Creek record, although not from a cave, is the first from a region of gypsum karst, the Northwest Texas gypsum karst (Smith, 1971), suggesting that populations of M. velifer occupied nearby gypsum caves in the late Pleistocene. I thank W. W. Dalquest for the opportunity to study this specimen.
TABLE 1. Quaternary occurrences of Myotis velifer in North America. Taxon Locality Age (rybp) listing M. (?) Papago Springs Cave, Arizona late Pleistocene velifer M. velifer O-Bar Cave. New Mexico 35,000 to 13,000 M. velifer Dry Cave. New Mexico Bison Chamber <14.470 and >10.730 Harris' Pocket 14.470 [+ or -] 250 Room of the Vanishing Floor 33.590 [+ or -] 1.500 M. velifer Muskox Cave, New Mexico 25.500 [+ or -] 1,100 to 18.140 [+ or -] 200 Texas Localities M. v. Quitaque Creek. Motley Co. 31.400 [+ or -] 5.600. magnamolaris >35.000 M. velifer Friesenhahn Cave. Bexar Co. 19.000-17.000. also ca. 9.000-8.000 M. velifer Longhorn Cavern. Burnet Co. late Pleistocene M. v. Fowlkes Cave. Culberson Co. late Pleistocene magnamolaris M. v. Fowlkes Cave. Culberson Co. pre-Columbian (late incautus Holocene) M. velifer Dust Cave. Culberson Co. late Pleistocene M. velifer Lower Sloth Cave. Culberson Co. 11,590 [+ or -] 230 M. velifer Upper Sloth Cave. Culberson Co. 11,760 [+ or -] 610. 11,060 [+ or -] 180. 10,780 [+ or -] 140. 10,750 [+ or -] 140 M. v. Schulze Cave. Edwards Co. 9,600; 9,300; middle magnamolaris Holocene M. velifer Cave Without a Name. Kendall Co. 10,900 [+ or -] 190 M. velifer Klein Cave. Kerr Co. early Holocene. "about 8,000 years old" M. velifer Miller's Cave. Llano Co. early Holocene. ca. 7,300, middle Holocene, ca. 3,000 M. velifer Zesch Cave. Mason Co. late Pleistocene M. v. Laubach Cave (Innerspace 23,230 [+ or -] 450. magnamolaris Caverns). Travis Co. (type 15,850 [+ or -] 500. locality of this subspecies) 13,970 [+ or -] 310 Taxon References listing M. (?) Skinner, 1942 velifer M. velifer Harris, 1987. 1989 M. velifer Harris, 1977, 1985. 1987, 1989 M. velifer Logan, 1981 Texas Localities M. v. Dalquest and Schultz, magnamolaris 1992; this paper M. velifer Graham, 1987 M. velifer Graham, 1987 M. v. Dalquest and Stangl. magnamolaris M. v. 1984 incautus M. velifer Van Devender et al., 1977; Harris, 1985 M. velifer Logan. 1983 M. velifer Logan and Black. 1979; Harris, 1985 M. v. Dalquest and Stangl. magnamolaris 1984; Graham, 1987 M. velifer Lundelius, 1967 M. velifer Roth, 1972; Kurten and Anderson, 1980 M. velifer Patton. 1963; Graham, 1987 M. velifer Graham, 1987 M. v. Choate and Hall, magnamolaris 1967; Valastro et al., 1977
Choate, J. R., and E. R. Hall. 1967. Two new species of bats, genus Myotis, from a Pleistocene deposit in Texas. Amer. Midland Nat., 78:531-534.
Dalquest, W. W. 1964. A new Pleistocene local fauna from Motley County, Texas. Trans. Kansas Acad. Sci., 67:499-505.
Dalquest, W. W. 1986. Vertebrate fossils from a strath terrace of Quitaque Creek, Motley County, Texas. Pp. 58-59, in Geomorphology and Quaternary stratigraphy of the Rolling Plains, Texas Panhandle (T. C. Gustavson, ed.), Univ. Texas Bur. Econ. Geol., Guidebook, 22:1-97.
Dalquest, W. W., and G. E. Schultz. 1992. Ice age mammals of northwestern Texas. Midwestern State Univ. Press, Wichita Falls, Texas, 309 pp.
Dalquest, W. W., and F. B. Stangl, Jr. 1984. The taxonomic status of Myotis magnamolaris, Choate and Hall. J. Mamm., 65:485-486.
Graham, R. W. 1987. Late Quaternary mammalian faunas and paleoenvironments of the southwestern plains of the United States. Pp. 24-86, in Late Quaternary mammalian biogeography and environments of the Great Plains and prairies (R. W. Graham, H. A. Semken, Jr., and M. A. Graham, eds.), Illinois State Mus. Sci. Paper, 22:xiv + 1-491.
Gustavson, T. C. (ed.) 1986. Geomorphology and Quaternary stratigraphy of the Rolling Plains, Texas Panhandle. Univ. Texas Bur. Econ. Geol., Guidebook, 22:1-97.
Harris, A. H. 1977. Wisconsin age environments in the northern Chihuahuan Desert: evidence from the higher vertebrates. Pp. 23-52, in Transactions of the symposium on the biological resources of the Chihuahuan Desert Region, United States and Mexico (R. H. Wauer and D. H. Riskind, eds.), Nat. Park Service Trans. Proc. Ser., 3:1-658.
Harris, A. H. 1985. Late Pleistocene vertebrate paleoecology of the West. Univ. Texas Press, Austin, 293 pp.
______. 1987. Reconstruction of mid-Wisconsin environments in southern New Mexico. Nat. Geogr. Res., 3:142-151.
______. 1989. The New Mexican late Wisconsin--East versus West. Nat. Geogr. Res., 5:205-217.
Kurten, B., and E. Anderson. 1980. Pleistocene mammals of North America. Columbia Univ. Press, New York, xvii + 443 pp.
Logan, L. E. 1981. The mammalian fossils of Muskox Cave, Eddy County, New Mexico. Proc. Eighth Intern. Cong. Speleol., 1:159-160.
______. 1983. Paleoecological implications of the mammalian fauna of Lower Sloth Cave, Guadalupe Mountains, Texas. Nat. Speleol. Soc. Bull., 45:3-11.
Logan, L. E., and C. C. Black. 1979. The Quaternary vertebrate fauna of Upper Sloth Cave, Guadalupe Mountains National Park, Texas. Pp. 141-158, in Biological investigations in the Guadalupe Mountains National Park, Texas (H. H. Genoways and R. J. Baker, eds.), Nat. Park Service Trans. Proc. Ser., 4:1-442.
Lundelius, E. L., Jr. 1967. Late Pleistocene and Holocene faunal history of central Texas. Pp. 287-319, in Pleistocene extinctions: the search for a cause (P. S. Martin and H. E. Wright, eds.), Yale Univ. Press, New Haven, Connecticut.
Menu, H. 1985. Morphotypes dentaires actuels et fossiles des Chiropteres vespertilionines. [I.sup.c] partie: Etude des morphologies dentaires. Palaeovertebrata, 15:71-128.
Patton, T. H. 1963. Fossil vertebrates from Miller's Cave, Llano County, Texas. Bull. Texas Mem. Mus., 7:1-41.
Roth, E. L. 1972. Late Pleistocene mammals from Klein Cave, Kerr County, Texas. Texas J. Sci., 24:75-84.
Skinner, M. F. 1942. The fauna of Papago Springs Cave, Arizona, and a study of Stockoceros; with three new antilocaprines from Nebraska and Arizona. Bull. Amer. Mus. Nat. Hist., 80:143-220.
Smith, A. R. 1971. Cave and karst regions of Texas. Pp. 1-14, in Natural history of Texas caves (E. L. Lundelius and B. H. Slaughter, eds.), Gulf Nat. Hist., Dallas, Texas, 174 pp.
Valastro, S., Jr., E. M. Davis, and A. G. Varela. 1977. University of Texas at Austin radiocarbon dates XI. Radiocarbon, 17:160-173.
Van Devender, T. R., W. G. Spaulding, and A. M. Phillips III. 1977. Late Pleistocene plant communities in the Guadalupe Mountains, Culberson County, Texas. Pp. 13-30, in Biological investigations in the Guadalupe Mountains National Park, Texas (H. H. Genoways and R. J. Baker, eds.), Nat. Park Service Trans. Proc. Ser., 4:1-442.
NICHOLAS J. CZAPLEWSKI
Oklahoma Museum of Natural History and Department of Zoology, University of Oklahoma, Norman, Oklahoma 73019
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|Title Annotation:||GENERAL NOTES|
|Author:||Czaplewski, Nicholas J.|
|Publication:||The Texas Journal of Science|
|Date:||Feb 1, 1993|
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