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NEW SPECIES OF SEPIIDA (, CEPHALOPODA) FROM THE EOCENE OF THE GULF COAST JAMES E. ALLEN R E SEA RCH ASSOCIA TE, PA L EONTOLOGICAL RESEARCH INSTITUTION

One species of Belemnosella Naef, 1922, nearly straight; fairly sturdy sheath obtusely and three species of Belosaepia Voltz, 1830, conical in apical quarter, quadrangular in cross section in anterior three-quarters, dorsal surface are described as new. Reports of both genera fl attened." (Jeletzky, 1966.) from the Jackson Group, upper Eocene, raise D iscussion: As Jeletzky ( 1966, p. 107) the stratigraphic range of each to that level pointed out, this is characterized by from the previously reported Claiborne an orthoconic . He thus cor­ Group, middle Eocene age. rected the misconception of the genus as The author gratefully acknowledges the reconstructed by Naef ( 1922, p. 49, text fig. assistance of the following persons: Dr. J. 12) . It is unfortunate that Fischer ( 1952, A. Jeletzky, Geological Survey of Canada, p. 390-391, text fig. 9-44) copied Naef in for furnishing specimens and references not the description of the obscure genus and previously seen; Dr. Harold E. Vokes and gave wide circulation to an erroneous con­ Dr. Emily H. Vokes, Tulane University, who cept. have loaned reference material, contributed BELEMNOSELLA FLOWER! (Palmer) specimens, and most graciously furnished the Plate 1, figs. 1-3 photography for the plates herein. Dr. Kath­ erine V. W. Palmer, Paleontological Research Diagnosis: "Belosepion small, composed of an elongate sheath, containing a rounded body Institution, who has been a constant source cavity, a short rostrum and a fine, flattened of inspiration, guidance, and help in more dorsal callus. The tip of the rostrum is broken. ways than can be enumerated. To her this The dorsal callus is finely rugose, expanded and flattened over the whole dorsal surface. The al­ paper is most gratefully dedicated. veolus has an inner calcareous layer. The cavity becomes constricted posteriorly, its entire sur­ SYSTEMATIC DESCRIPTIONS face is covered by the calcareous inner layer. The tip of the alveolus may curve ventrally. The Phylum MOLLUSCA calcareous inner layer has definite, concentric septae as in Belosaepia. Ventrally, the sheath, Class CEPHALOPODA Cuvier, 1794 anterior to the rostrum is enlarged, expanding laterally but with a deep, short concavity at the Subclass COLEOIDEA Bather, 1888 margin of the alveolus. The surface of the en­ Order SEPIIDA Zittel, 1895, em end. N aef, larged area is minutely granular as is most of the surface of the sheath." ( Pahner, 1937. ) 1916 [nom. correct. Jeletzky, 1965 ( pro Dimensions of holotype: Length, 15 mm; Sepioidea Zittel, 1895, em end. Naef, 1916) ] greatest width, 6.5 mm. Holotype: PRI 3402. Family BELEMNOSEIDAE Naef, 1921 Type locality: Alabama River at Claiborne, [nom. correct. ] eletzky, 1966 ( pro Monroe County, Alabama. Figured specimen: PRI 27548, length 18 mm; Belemnosidae Naef, 1921) ] areatest width, 8.5 mm; locality: Red River below Montgomery Landing, Grant Parish, Genus BELEMNOSELLA Naef, 1922 Louisiana. Belemnosella NAEF, 1922, Die Fossilen Tinten­ Occurrence: Middle Eocene, Gosport Sand, fische, pp. 48-50. uppermost Claiborne Group. Upper Eocene. Type species, Belemnosis americana Meyer Moodys Branch Fm., Jackson Group. and Aldrich, 1886, by monotypy. D iscussion: This is the first report of the Advena PALMER, 1937, Bulls. Amer. Paleon­ genus Belemnosella above the middle Eocene tology, v. 7, no. 32, p. 510. [Not Advena Gude, 1913, Malac. Soc. London, Proc., v. Claiborne Group of the Gulf Coast Eocene 10, p. 391 (Mollusca).] and accordingly extends its range both strati­ Type species, Advena floweri Palmer, by graphically and geographically. original designation. Anevda PALMER, 1940, Jour. Paleontology, v. BELEMNOSELLA PALMERAE Allen, n. sp. 14, no. 3,p. 285. . Type species, Anevda [ = Adve na] flow en Plate 1, figs. 4-6 Palmer, by original designation. Diagnosis: Sheath and phragmocone typical Diagnosis : "Phragmocone long and straight, of the genus. Proostracum missing as is the tip reaching almost to the tip of sheath, sutures of the rostrum. Rostrum long, tapers evenly and 33 34 Tulane Studies in Geology Vol. 6 curves ve1y slightly dorsally. The dorsal shield finely rugose posteriorly becoming more rugged reaches its maximum width slightly anterior to anteriorly where it is characterized by a series the greatest width of the ventral callus and of longitudinal ridges with prominent pits and from that point tapers anteriorly. The anterior transverse ridges between covering the entire tapered portion of the dorsal shield is approxi­ dorsal surface. Ventral plate wide, striated, with mately 25% of the total length of the shell. concentric threads that give the striations a Known only from a single specimen. dentate appearance under the lens. The ventral Holotype, PRI 27549. plate is strongly marked on its projected dorsal Dimensions of holotype: Length 27 mm; surface and the shell is sculptured with strong greatest width, estimated, 7.5 mm. furrows and rugosities above the ventral plate Type locality: Red River below Montgomery anterior to the base of the rostrum. Internal Landing, Grant Parish, Louisiana. septae weakly marked and somewhat irregularly Occurrence: Upper E ocene, Moodys Branch spaced. Fm., Jackson Group. Dimensions of holotype : Length 21 mm; Discussion: B. palmerae is closely related greatest width 13 mm. to B. floweri and as both species are present Holotype: PRI 27550. Type locality: Claiborne Bluff on the Ala­ at the same locality additional material that bama River, 1/4 mile below the bridge on U. S. would furnish a complete series may prove Highway 40, Monroe County, Alabama. them to be conspecific. B. palmerae is herein Occurrence: Middle Eocene, Gosport Sand, specifically separated because of the differ­ uppermost Claiborne Group. Discussion: B. vokesi is apparently closely ence in the seating and shape of the rostrum related to B. ungula Gabb, as figured by and the much more slender and elongate Cossmann ( 1893, pl. 2). Rostrum is more form of the sheath. The rostrum of B. floweri compressed laterally, shell expanded rnore is short, tapers abruptly, and is slightly curved strongly anteriorly and the dorsal callus is ventrally. That of B. palmerae is much longer, neither as prominent nor formed as abruptly tapers evenly, and is slightly curved dorsally. anterior to the rostrum. This species is named in honor of Dr. Named for Dr. Harold E. Vokes, Tulane Katherine V. W. Palmer, Paleontological Re­ University, the collector. search Institution. BELOSAEPIA STENZEL! Allen, n. sp. Family SEPIIDAE Kerferstein, 1866 Plate 2, figs. 1-8 Subfamily BELOSAEPIINAE Naef, 1921 Diagnosis: Belosepion small, short and much expanded laterally in proportion to length of [nom. correct. herein ( pro shell. Rostrum short, sharp and hooked dorsally. Belosepiinae N aef, 1921 ) ] The entire dorsal surface is deeply rugose. Ventral plate narrow, generally smooth with a Genus BELOSAEPIA Voltz, 1830 few radial ridges. Internal septae strongly Belosaepia VoLTZ, 1830, Mem. Soc. Hist. Nat. marked. Strasbourg, v. 1, pp. 22-23. Dimensions of holotype: Length 11.2 mm, Type species: Beloptera sepioidea Blainvill e greatest width 14 mm. Paratype: Length 12.4 = Belosaepia cuvieri ( d'Orbigny), by original mm, greatest width 12 mm. designation. Holotype: PRI 27551; paratype: PRI 27552. Type locality: Mouth of Saline Bayou, St. BELOSAEPIA VOKES! Allen, n. sp. Maurice, Winn Parish, Louisiana. Plate 1, figs. 7-10 Occurrence : Middle Eocene, Cook Mountain Fm., Saline Bayou Member, Claiborne Group. Diagnosis: Belosepion of medium size. The Discussion: B. stenzeli may be readily rostrum is short for the size of the shell; curved separated from any described American or dorsally and regularly tapered in the lateral view; laterally compressed and tapered abruptly European species by the short, hooked as seen in the dorsal view. The shell is laterally rostrum. Except for the presence of the expanded anterior to the rostrum. Dorsal callus ventral plate the species bears a remarkable

PLATE 1 Figures Page 1- 3 Belemnosella flo weri ( Palmer), PRI 2 7 548, X2lh __ ------3 3 4- 6 Belemnosella palmerae Allen, n. sp., holotype, PRI 27549, X2 1h ______33 7-10 Belosaepia vokesi Allen, n. sp., holotype, PRI 27550, X21h ______34 No.1 New Eocene Species of Sepiida 35

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PLATE 1 36 Tulane Studies zn Geology Vol. 6 resemblance to vera Deshayes ( Coss­ BELOSAEPIA sp. mann and Pissarro, 1907-1913, pl. LX) which leads this writer to believe it may One speomen, too poor to serve as type be a transitional form. material, has been collected by the author Named for Dr. H. B. Stenzel, Louisiana from the Jacksonian Moodys Branch Forma­ State University, in recognition of his long tion at Montgomery, Louisiana. The occur­ and distinguished career in Gulf Coast rence is noted as the first report of Belo.raepict paleontology. from the Jackson Group of the Gulf Coast Eocene and may alert other workers to the BELOSAEPIA JELETZKYI Allen, n. sp. collection of additional material. Plate 2, figs. 9-12 Specimen: PRI 27554. Diagnosis: Belosepion small short and rela­ tively narrow laterally. Rostru~ short and blunt· tip missing. The ventral line of the rostrum de~ REFERENCES scribes a curve dorsally from the base to the CossMANN, A. E. M., 1893, Notes complemen­ posterior tip. The shell is sharply constricted taires sur la faune EocEmique de I' Alabama: laterally anterior to the base of the rostrum so Ann. Geol. et Paleontologie, livr. 12, 51 p., 2 that in both the dorsal and ventral views the pls. rostrum appears to be swollen. CossMAr , , A. E. M., and G. PISSARRO, 1907- The dorsal callus is prominent, making the 1913, Iconographie complete des coquilles shell higher than its maximum width. The entire fossiles de !'Eocene des environs de Paris, v. shell surface is smooth with no rugosities, pits or other irregularities common to the genus. Ex­ 2, 65 pls. aminations of the shell wall at the broken an­ FISCHER, A. G., in MooRE, R. C., C. G. LA­ terior section shows that the shell material is LICKER, and A. G. FISCHER, Invertebrate Fos­ relatively porous and contains small cavities sils. McGraw-Hill, New York. , within the wall but they apparently nowhere p. 335-397, text figs. 9-1 through 9-50. reach the surface and the resulting density is }ELETZKY, J. A., 1966, Comparative morphology, greater than in any species examined. The ven­ phylogeny and classification of fossil Coleoi­ tral plate is large and is somewhat folded with dea: Univ. Kan. Paleon. Cont., Mollusca, Ar­ radial ridges which are crossed by microscopic ticle 7, p. 1-162, pls. 1-25, figs. 1-15. concentric threads. The ventral surface of th~ MEYER, OTTO, and T. H. ALDRICH, 1886, The plate is curved laterally following the contour fauna of Newton and Wautubbee, of the body of the belosepion. Miss.: Cincinnati Soc. Nat. Hist., Jour. v. 9, Dimensions of holotype: Length 15.6 mm, no. 2, p. 40-64, pl. 2. greatest width 8.4 mm. NAEF, ADOLF, 1922, Die Fossilen Tintenfische. Holotype: PRI 27553. Gustav Fischer, Jena. 382 p., 101 figs. Type locality: Mouth of Saline Bayou, St. PALMER, K. V. W., 1937, The Claibornian Maurice, Winn Parish, Louisiana. Scaphopoda, Gastropoda and Dibranchiate Occurrence: Middle Eocene, Cook Mountain Cephalopoda of the Southern United States. Fm., Saline Bayou Member, Claiborne Group. Bull. Amer. Paleontology, v. 7, no. 32, p. . Discussion: B. jeletzkyi differs markedly 1-548, pls. 1-90. PALMER, K. V. W., 1940, Anevda, new name m two respects from other American species for Advena Palmer, 1937, not Gude, 1913. of the genus. The strong lateral curvature of Jour. Paleontology, v. 14, no. 3, p. 285. the ventral plate and the smooth external STENZEL, H. B., 1941, The Eocene Dibranchiate genus Belemnosella Naef 1922 surface of the belosepion may represent more ' ' than a specific difference but it seems unwise = A d vena Palmer, 1937 = Anevda Palmer, 1940: Jour. Paleontology, v. 15, no. 1, p. 90. to make any other assignment until more, VoLTZ, M., 1830, Observations sur les Belem­ and perhaps better, material is available. nites: Mem. Soc. Hist. Nat. Strasbourg, v. 1, Named for Dr. J. A. J eletzky, Geological p. 1-72, pls. 1-8. Survey of Canada, to honor his exhaustive works on the Coleoidea. July 31, 1968

PLATE 2 Figures Page 1- 8 Belosaepia stenzeli Allen, n. sp., X21;2. 1-4, holotype, PRI 27551; 5-8, paratype , PRI 2 7 55 2 ______-----·------34 9-12 Belosaepia jeletzkyi Allen, n. sp., holotype PRI 27 55 3, X2 1f2 ______36 No.1 New Eocene Species of Sepiida 37

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