TWO NEW SPECIES OF MURICINAE FROM THE CRETACEOUS AND PALEOCENE OF THE GULF COASTAL PLAIN WITH COMMENTS ON THE GENUS ODONTOPOLYS GABB, 1860 C.L.GARVIE HOUSTON, TEXAS* I. ABSTRACT Genus POIRIERIA Jousseaume , 1880 Two new species of muricid gastropods Poirieria JOUSSEAUME, 1880, L e Naturali::.te, are described: Poirieria (Paziella) cre­ An nee 2, no. 42, p. 335. tacea, from the Kemp Clay (Cretaceous: Type s pecies : Murex zelandicus Quoy and Maastrichtian) in Te xas, a nd Pteryrwtus Gaimard, 1833, by original designa tio n. (Pterynotus) aurorae, from the Be ll s Land­ ing Marl Membe r of the Tuscahoma For­ Subgenus PAZIELLA Jousseaume, 1880 mation (Paleocene) of Alabama. The new Paziella J OUSSEAUME, 1880, Le Naturalistc, species of Poirieria is the first reported oc­ An nee 2, no. 42 , p. 335. currence of a muricine to be d iscovered in Type species: Murex pazi Crosse, 1869, by the Cretaceous of the New World a nd only original desig nation. the second worldwide . The p reviously known species from Saxony, easte rn Ger­ POIRIERIA (PAZU:LLA) CH. ETACEA many, is a seconda ry homonym and is re­ C.L. Garvie, n. sp. named Poirieria (? Paziella) cenomae Plate I fi gures 1, 2 herein. Examination of the type species of Description: Protoconch initially of 112 whorl, the genus Odontopolys Ga bb, 1860, indi­ enrolled, acute , followed by 3 1/2 smooth, cates its relationship to the genus V it­ rounded whorls, first va ri x appearing at the lower point of the whorl. The fi rst teleoconch ularia. whorl with six lame lla r cu rved varices, succes· sive ones incre asingly protruding from the bot­ II. ACKNOWLE DGMENT S tom of the whorL Six or seven varices on the The writer gra tefull y acknow le d ges the spire whorls and fi ve on the adult body whorl. assistance and encouragement of Emil y H . Varices, thick, heavy, angular on the shoulder Vokes and David T. Dockery, III. In ad d i­ and swinging forwa rd strongly above the shoul· der, meeting the preceeding whorls at an acute tion, Emily H. Vokes kind ly su ppli e d angle. Surface smooth, no visible spiral photographs of the Poirieria a nd Odon­ sculpture on s pire; body whorl with five or six topolys specime ns . Tha nks a lso go to K laus weak rounded cords in the intervaricial area Bandel who kindly permitted me to state from the shoulde r to the canal. Aperture trian· some conclusions from a pape r he has in gular in outline, outer lip with two denticles preparation on Cre taceous gastropods. Fi­ under the shoulder area and seven on the re­ nally, I would like to thank my wife S hi r­ maining portion. Inner li p smooth with a moder­ ley, who found the first specimen of the ate deposit of callus and an incipient denticle under the top of the w horl. Siphonal canal short, Cretaceous muricine. open and mode ra te ly recurved. Dimensions o.fholotype: height 16.5 mrn, diam­ III. SYSTEMATIC DESCRIPTIONS eter 10.1 m m. Holotype: USNM 455526. Phylum MOLLUSCA Type locality: Colorado river, blufT on left Class GASTROPODA Cuvie r, 1797 bank at Web be r vi lle, Travis County, Texas. U Subclass PROSOBRANCHIA S. Geologica l Survey locality 7601. Milne-Edwards, 1848 Occu rren ce: Kemp Clay·, Upper Cretaceous Order NEOGASTROPODA Wenz, 1938 (Maastrichtian). Superfamily MURICACEA Discussion: The Muricacea has been Rafinesque, 1815 thought to be well-represented in the Late Family MURICIDAE da Costa, 1776 Cretaceous of the New World by the Subfamily MURICINAE da Costa, 1776 muricid subfamilies Rapaninae and Moreinae with genera Ecphora, Sargana, Morea, Paramorea, and Schizobasis and *Mailing address: P.O. Box 691091, Houston, TX the family Magilidae, with the genera 71269 Latiaxis and Lowenstamia. See Sohl, 87 88 Tulane Studies in Geology and Paleontology Vol. 24 (1964) for discussion of many species from gated, has fewer and less foliated varices, the Ripley, Owl Creek and Prairie Bluff even less spiral sculpture than P. harrisi formations. However, examining the pro­ and two more denticles on the outer lip. toconchs of some of the well-preserved Five specimens were recovered from the fauna of the Coffee Sand in Mississippi, Kemp Clay, two adult and three juveniles Klaus Bandel (pers. comm.) has shown (one now lost). One juvenile has the lower that Sargana is a close relative of the part of the body whorl broken off and Trichotropid branch of the Mesogas­ shows a columellar groove within the tropoda and Lowenstamia is probably a spire, a feature that is not visible in the member of the Ficidae. The genus Ec­ aperture of the other unbroken specimens. phora , or a close look-alike has been re­ The Webberville location where the ported from the Cretaceous by Soh!, but specimens were found was collected by according to both Klaus Bandel and Emily Stephenson and Deussen in 1911 and does Vokes (pers. comm.) its systematic place­ not seem to have been commented on ment is incorrect. Petuch (1988, p. 12) con­ since then. As with many other localities siders it to be an "unnamed subgenus" of on the Colorado river, it has greatly de­ Sargana. teriorated since the series of dams was constructed upstream from Austin and With regard to the subfamily Muricinae, regular scouring by floodwaters no longer even world-wide only one species has takes place. Both adult specimens show been reported, Murex armatus Geinitz, evidence of abrasion, a condition also seen 1874, from the Late Cretaceous (Cenoma­ in many of the other larger gastropods nian) of Saxony, eastern Germany. As from this location. The bulk of the fauna is Vokes (1970, p. 5) noted, that name is found in one thin layer that appears to be a preoccupied by M. armatus A. Adams, channel deposit. 1854. The Saxony species is herein re­ named Poirieria (?Paziella) cenomae. An The Kemp Clay (Navarro Group) is the examination of Geinitz's two figures of highest stratigraphic unit in the Upper Murex arrnatus shows a shell with seven or Cretaceous series of Texas; Stephenson eight varices terminating in long open (1941) gives a description of the diverse spines. On the apertural view the illustra­ fauna of 105 species of which 99 are Mol­ tion also shows weak spiral sculpture on lusca and their relationships to equivalent the shoulder area. The aperture is broken ones worldwide. Stephenson interpreted so one cannot know whether denticles the environment as being marine, not ex­ were present; Vokes, (1970, p. 5) was con­ ceeding 100 fathoms in depth. fident it had a long, extended canal. With­ At Webberville the middle part of the out a hand examination one cannot abso­ Kemp Clay is exposed and consists of lutely place the species but it appears to be black carbonaceous shales and sandy clay. a Paziella. Given the time interval of at The fossil fauna shows evidence of being least 26 million years between the deposits transported in agitated conditions. Most of containing Murex armatus and those con­ the fauna is found in thin sandy layers that taining P. cretacea, it is surprising that the often include fragments of fossil wood. The two species are so closely related. With smaller specimens are most often found on such strong muricine characters already the lee side of large mollusk fragments, present in P.cenomae and the apparent which are commonly fragments of an am­ slow evolution of the genus, indications are monite. Approximately five miles north, at that the ancestral stock must have ap­ the Littig clay pit, Kocurek (1 978) has inter­ peared much earlier, perhaps near the be­ preted the Kemp environment as deltaic, ginning of the Cretaceous. prodelta with shelf deposits; the proximity of the delta could explain the depositional The closest species to P. cretacea is environment. The Cretaceous fauna at the Poirieria (Paziella) harrisi E. H. Vokes, Littig clay pit itself is very meager, the only 1970, to which it bears a close resemblance species the author has been able to find and which is in all probability its descen­ are a few poorly preserved specimens of dant. The Cretaceous species is more elon- Tell ina spp. and Nucula spp. No.4 CTetaceous and Paleocene Muricinae 89 Genus PTERYNOTUS Swainson, 1833 matthewsensis lacks the intervaricial nodes Pterynotus SWAJNSON, 1833, Zool. Illust., (Ser. but is more strongly shouldered and bears 2) vol. 3, expl. to pl. 100. prominent spines. Ty pe species: Murex pinnatus Swainson, The Tuscahoma Formation of the 1822, by s ubsequent designation, Swainson, Sabine Stage has long been considered to 1833. be of Early Eocene age. Recent dating using nannoplankton has established an Subge nus PTERYNOTUS s.s. NP 9 zone age (see Siesser, 1983), which corresponds to a Thanetian (Paleocene) PTERYNO'I'US (PTERYNOTUS) A URORAE age. C.L. Garvie, n. sp. Plate I, fi gures 3, 4 Genus ODONTOPOLYS Gabb, 1860 Description: Whorls six (protoconch missing Odontopolys GABB, 1860, Acad. Nat. Sci. Phila­ and first two extant whorls very worn), rounded delphia, Jour., (Ser. 2) vol. 4, pt. 4, p. 317. and ve1·y slightly shouldered. Suture impressed Type species: Murex compsorhytes Gabb, and margined below with a slight subsutural 1860, by original designation. swe lling. Three foliated ruffled varices per whorl, the line of the varices making a slight Discussion: The type species of Odon­ adapertural spiral down from the apex. Inter~ topolys Gabb, 1860, was described from the varicial axial sculpture consisting of about live Wheelock Member of the Crockett Forma­ weak, irregular ribs angling fo1·ward on the tion in Texas.
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