OLIVINAE (MOLLUSCA:GASTROPODA) FROM THE ALUM BLUFF GROUP OF NORTHWESTERN FLORIDA PAULE. DREZ UNIVERSITY OF NORTH CAROLINA • CHAPEL HILL, NORTH CAROLINA CONTENTS Page I. ABSTRACT ..... ························· • · ~~ II. INTRODUCTION . .............. 105 III. ACKNOWLEDGME.NTS .. ... 106 Iv. sYsTEMATic DEscRIPTioN-s· ........... 107 V. LOCALITYDATA VI. LITERATURE ... 120 CITED: ............. .............. 121 ILLUSTRATIONS PLATE 1 Ill PLATE2 117 I. ABSTRACT included by Dall in his monumental work on The subfamily Olivinae encompasses six the Tertiary fossils of Florida and adjacent species and one subspecies in the Alum areas. The two forms, 0. liodes and 0. Bluff Group (lower to middle Miocene) of (Omogymna) martensii, were figured (1903, northwestern Florida. Of these, three pl. 58, figs. I and 4) and listed in his faunal species and one subspecies previously de­ list (ibid., p. 1576) but were not described. scribed are reviewed. The subspecies is Later, Gardner (1937) described Dall's two raised to specific rank, and two of the three species and added a new subspecies of 0. species receive a new subgeneric or generic liodes from the Shoal River Formation 0 assignment. Two new species are de­ liodes waltoniana. ' . scribed: Oliva blowi, from the Chipola and More recent collections have provided an Oak Grove faunas, and Oliva vokesorum, abundance of olivid specimens for study, from the Chipola only. A new subspecies, particularly from the Chipola Formation. Oliva waltaniana calhounensis, is named The author had over 4600 specimens avail­ from the Chipola and Oak Grove units. able (Chipola-4515, Oak Grove-7 Shoal Thus, there is a total of five species of Oliva River-167), as compared to 390 sp~cimens in the Chipola Formation, four of which also for Gardner (Chipola-28, Oak Grove-21 , occur in the Oak Grove Sand. One species Shoal River-341). Gardner's greater per­ of Oliva is confmed to the Shoal River For­ centage of specimens from the Shoal River mation, and one specime n of a second spe­ Formation and the Oak Grove Sand (which cies has been collected there. The genus is probably a facies of the Chipola Forma­ Jaspidella is limited to a single species in the tion) was due in part to her collections from Chipola Formation. many localities that have eluded subse­ quent workers. II. INTRODUCTION Dall and Gardner failed to notice, on their Only two species of Oliva from the Alum specimens of 0. liodes, the minute de­ Bluff Group of northwestern Florida were pressed posterior band that is characteristic of the subgenus Omogymna. Other speci­ mens of this species often show a slightly *Present address: Exxon Production Research wider band (:': 1.2 mm), which occasionally Company, Houston, Texas is visible to the unaided eye. Oliva EDITORIAL COMMITTEE FOR TillS PAPER: A. MYRA KEEN, Department of Geology, Stanford University (Emeritus), Stanford, California AXEL A. OLSSON, Coral Gables, Florida DRUID WILSON, United States Geological Survey, Washington, D.C. 105 106 Tulane Studies in Geology and Paleontology Vol.16 (Omogymna) martensii is another member most characteristics but with a narrow de­ of this subgenus in the Alum Bluff Group. pressed posterior band on the whorls. The Chipola and Oak Grove faunas repre· The genus Jaspidella is represented by sent the only known occurrence for the small Olivella-like species, with a large, ob­ presence of two species of Omogymna in the tuse nucleus on a high spire. The parietal western Atlantic. Oliva liodes waltoniana is wall usually lacks any callus above the col­ here raised to specific rank due to different umella folds. Jaspidella may have evolved subgeneric assignments for 0. liodes and 0. out of small Agaronia-like forms, making its waltoniana. Olivella cofacorys Gardner first appearance in the Oligocene of Florida was recognized by Olsson (1956, p. 212) to be (Suwannee Limestone), as "Olivella" live­ a member of the Olivinae genusJaspidella. oakensis (Mansfield, 1937, p. 96). Jaspidella The subfamily Olivinae apparently e­ has a meager representation in the Tertiary volved from Agaronia-like forms during the of the western Atlantic, and is now repre­ Jacksonian-Vicksburgian Stages (upper sented by three known Recent species. Eocene-middle Oligocene), first as the Today, olives are carnivorous gastropods genus Strephonella. * Oliva s.s. and that inhabit sandy bottoms in temperate to Omogymna made their first appearance in tropical seas. They generally prefer shallow the late Oligocene and lower Miocene, to intertidal areas, but some species are thereafter rapidly diversifying and multi­ known to occur rarely at much greater plying. Oliva s.s. reached its greatest de­ depths (Zeigler and Porreca, 1969, p. 69). velopment during the late Miocene to mid­ The members of the subfamily Olivinae dle Pliocene in the western Atlantic and is often show considerable variation within a now represented by only four known species. This is particularly true of some species in this area. Omogymna reached its species from the Alum Bluff Group. Be­ greatest development in the lower Miocene cause of the large number of specimens and decreased in diversity and numbers available for this study, many variations thereafter. The last known occurrence of have been shown to occur within a species, this genus in the western Atlantic is the mid­ which might have resulted in overnaming dle Pliocene Agueguexquite Formation of with fewer specimens. Mexico (see Akers, 1972, p. 30; 1974, p. 120). The author had found as constant criteria Oliva s.s. is characterized by a medium­ for differentiation of species within a genus sized to large shell, ovate-cylindrical to cy­ or subgenus: the number and shape of the lindrical in outline, with a low to medium nuclear whorls and the nature of the first spire, and teleoconch whorls separated by a teleoconch whorl; the width and depth of distinct channeled suture that usually has a the suture; the nature of the intrasutural border of callus. The last whorl generally callus; the overall nature of the slope of the conceals most of the preceeding whorls, spire (convex or concave). O-ther factors terminating in a smooth outer lip. The pari­ such as height of spire, number and etal callus is usually thick, with many weak strength of lirae and plications, degree of brae, stronger anteriorly. The columella is convexity or concavity of spire, extent of strong and heavy, with two or more oblique coverage of intrasutural callus, may be vari­ phcatwns around the base. The posterior able within a species. canal is notch-like, with the aperture widen­ mg anteriorly, ending in an emarginated III. ACKNOWLEDGMENTS siphonal canal. A very special note of gratitude goes to The subgenus Omogymna has a small to Drs. Harold E. and Emily H. Vokes, without medium-sized shell similar to Oliva s.s. in whose constant encouragement and advice this paper would not have been possible. Gratitude is also expressed to them for the *The earliest known olivid is a species of Streph­ excellent photographs and the loan of many one.lla, "Oliva" mississippiensis Conrad, 1847, specimens from the Tulane University col­ wh1ch was described from the Vicksburg Oligo­ cene. Subsequent workers have generally lections. A special thanks goes to Robert placed this species in the genus Agaronia. and the late Shirley Haerle, West Palm Palmer (in Harris and Palmer, 1947, p. 410, pl. Beach, Florida, and to Warren Blow, 63, figs. 17 -19) reported similar forms from the Washington, D.C., for the generous loan of Moody's Branch Marl, Jacksonian upper Eo­ specimens from their personal collections. ce ne, near Montgomery, Louisiana. The writer is also indebted to Thomas R. No.1 0/i<•inae.from Alum Blt\[f'Group 107 Walle r and Wende ll P. Woodring, of the some authors (Olsson and Harbison, 1953. U .S. National Museum, and Druid Wilson, p. 182; Weisbord, 1962, p. 362) have placed of the U.S. Geological Survey, for the loan the western Atlantic olives in the subgenus of comparative material. Ispidula Gray, 1847, with 0. ispidula (of Fina lly, the writer is deeply appreciative authors non Linneaus 1758) as the type of of the help and constructive criticisms of the the subgenus. Wenz (1 943, p. 1280) put e ditorial committee, who have added much Ispidula Gray, 1847, in synomony with to this pape r. Oliva Martyn, 1786. Olsson a nd Dance (1 966, p. 215-222) ex­ IV. SYSTEMATIC DESCRIPTIONS a mined the types of the three Linnean olives: Volu ta porphyria , Voluta oliva and Phylum MOLLUSCA Voluta ispidu la. Their fi ndings are sum­ Class GASTROPODA marize d below. The reader is referred to Subclass PROSOBRANCHIA the article for a more complete discussion. Order NEOGASTROPODA especia lly in reference to the d ifferentiation Superfamily VOLUTACEA of the true Linnean types. Family OLIVIDAE Swa inson, 1840 Volu ta oliva was found to be the type for Subfa mily OLIVINAE Swainson, 1840 the genus Oliva Bruguie re, by tautonomy Ge nus OLIVA Bruguie"e, 1789 and subsequent monotypy. The tray in the Subgenus OLIVA s.s. L innean collection with the name Voluta Oliva BRUGUIERE. 1789. Encycl. Meth. tVersl. oliva contained five specimens. Four un­ v. I. p. X V (genus w ithout named species). marked specimens in the tray were refer­ Type species: Voluta oliva Linnaeus (=0. is­ able to 0 . maura Lamarck and are assumed pid'Ula of authors, not of Linnaeus) by tautonomy to have been added to the collection after and m ono ty py. the dea th of Linneaus, but before it was Di scussion: In the past. there has been acquired by the Linnean Society. The one m uch confusion about the correct citation numbered specimen was identifi ed. upon for the a uthor of the genus Oliva. The re comparison with Oliva specimens in the a lso has been confusion over the type U.S.