COLOR PATTERNS ON PENNSYLVANIAN GASTROPODS FROM OHIO1 R. D. HO ARE, Department of Geology, Bowling Green State Univ., Bowling Green, OH 43403 M. T. STURGEON, Department of Geology, Ohio University, Athens, OH 45701 Abstract. Gastropods are among the more common fossil forms with preserved color patterns. Numerous species of Carboniferous gastropods have been previously re- ported in Europe and North America including 9 species from the Pennsylvania!! of Ohio. Our collections of Pennsylvanian gastropods, made over the past several years, contain specimens representing 11 species with remnants of color patterns, 9 not previously reported from Ohio. The color patterns of 4 of these species, Ian- thinopsis intercalaris? (Meek & Worthen), Palaeostylus (Paleostylus) n. sp., Palaeo- siylus {Pseudozygo pleura) n. sp. 1 and Palaeostylus {Pseudozy go pleura) n. sp. 2, have not been described before. Comparisons were made between Ohio gastropods with color patterns, or closely related forms, and those reported elsewhere. Variation in patterns were noted and illustrated where possible. OHIO J. SCI. 78(1): 3, 1978 Preserved color patterns in fossils have tropod species previously reported from been intermittently reported since Bru- the Pennsylvanian strata of Ohio have guiere (1792) illustrated specimens of the been described by Sturgeon (1964), bivalve Gryphaea, with radiating brown Bellerophon (Pharkidonotus) percarinatus bands, from the Cretaceous of Ireland. (Conrad) and Euconospira turbiniformis Over 200 reports describing or illustrating (Meek & Worthen); Lee (1971), Eucono- color patterns on fossils have been pub- spira turbiniformis (Meek & Worthen); lished since that date, a large number of Morningstar (1922), Naticopsis {Marmo- which pertain to gastropods, one of latella) pulchella n. sp.; Webb (1972), the more common groups of organisms Euconospira riddelli (Shumard), Lepto- in which patterns are preserved. tygma virgatum (Knight), Bellerophon {Pharkidonotus) percarinatus (Conrad), Paleozoic examples of this type of Bellerophon {Bellerophon) graphicus preservation are not as uncommon as Moore, Knightes {Cymatospira) sp., and might be expected. Newton (1907) gives Ianthinopsis paludinaeformis (Hall); and, a summation of European occurrences of Hoare and Sturgeon (1976), Baylea sp. color pattern preservation, noting 13 [ = Callistadia n. sp.]. Paleozoic species of cephalopods, pele- Continued collecting of Pennsylvanian cypods and gastropods, three of which are invertebrates in the Ohio Pennsylvanian gastropods of Carboniferous age. Foerste by the authors and their students has un- (1930), in a summary paper of known oc- covered specimens representing 11 spe- currences of cephalopods, brachiopods, cies with preserved color patterns, 9 of gastropods and bivalves with preserved which have not been previously reported color, lists 44 Paleozoic species of gastro- from Ohio, and 4 species, Ianthinopsis pods, with 33 being of Carboniferous age. intercalaris? (Meek & Worthen), Paleo- Since 1930, specimens of at least 22 stylus {Paleo stylus) n. sp., Paleo stylus Paleozoic species of gastropods, with {Pseudozy go pleura) n. sp. 1 and P. color patterns preserved, have been de- {Pseudozy go pleura) n. sp. 2 that have not scribed in the literature; 11 are from the been previously described with preserved Pennsylvanian of North America. Gas- patterns. In several cases these 11 spe- manuscript received May 25, 1977 (#77-42). cies were represented by single specimens R. D. HOARE AND M. T. STURGEON Vol. 78 but there were several instances where cord ll/i Quadrangle. Specimens col- lected from the shale on the spoil several specimens were present, providing banks. information as to the variability of the Jmi-2. The Vanport Limestone and Shale ex- color pattern within the species. Varia- posed at a small abandoned drift mine tion from previously described patterns on the north side of Buffler Run, S cen- ter sec. 24, Milton Township, Jackson for a species was noted and is listed under County, Ohio. Mulga 7J^' Quadrangle. the color pattern descriptions. Specimens were collected from the 0.5 The figures were produced by drawings foot shale zone just above the Vanport made directly from specimens or from Limestone. LIuc-1. The Lower Mercer Limestone exposed photographs of specimens. Most speci- at an undescribed and uncertain lo- mens were incomplete or distorted. Some cality near Flint Ridge, Ohio. generalized reconstruction was necessary Mp-2. The Vanport Limestone exposed at the to indicate the general form or whorl pro- Carbon Limestone Co. quarries, 0.75 file of specimens but when major portions mi. south of U.S. 224 and just west of the Ohio-Pennsylvania state line near of the shell were missing, they were not Kansas Corners, Poland Township, added. Only the basic shell form and Mahoning County, Ohio. Campbell major features of ornamentation have 73^2' Quadrangle. Specimens collected been indicated so that the color pattern, from weathered limestone blocks. No-4. The Portersville Shale exposed in road- indicated by stippling, is not obscured. cut on the east side of U.S. 21, SEJ4 The pattern represented in the drawings SE^ sec. 10, Olive Township, Noble is as preserved and no attempt was made County, Ohio. Caldwcll South 7^' to reconstruct a total pattern. Descrip- Quadrangle. Specimens collected from shale exposure. tions and illustrations of the new species Pr-3. The Lower Mercer Limestone exposed indicated herein are being published in the B & O RR cut, N\V}| sec. 10, at separately. Repositories for the illus- Somerset, Reading Township, Perry trated specimens are given in the figure County, Ohio. Somerset i^/i Quad- rangle. Specimens collected from legends as: The Ohio State Univer- weathered blocks of limestone. sity, OSU; Ohio University, OU; Bowling Ty-3. The Putnam Hill Limestone and Shale Green State University, BGSU. exposed in a small abandoned borrow pit and strip mine of the Zoar Mining COLLECTING LOCALITIES Co., N\\T14 sec. 17, south of New Cp-3. The Columbiana Limestone at the Philadelphia, York Township, Tusca- rawas County, Ohio. New Phila- abandoned Brookwood Mine (type ] locality for the Columbiana), SE^4 delphia 7}4 "Quadrangle. Specimens NWM sec. 29, Perry Township, Co- collected from a 1-2 foot shale zone lumbiana County, Ohio. Salem 7^' just above the Putnam Hill Limestone. Quadrangle. Specimens collected from the mine dump. DISCUSSION OF COLOR PATTERNS CS1-1. The Lower Mercer Limestone and The preservation of color patterns on Shale exposed in a roadcut on the fossil specimens commonly shows varia- north side of U.S. 36, 1.0 mi. east of tion within a species. In some instances jet. with Ohio 93, NE^ sec. 1, approx. this variation probably is caused by in- 2.0 mi. northeast of West Lafayette, Lafayette Township, Coshocton complete preservation of the pattern on County, Ohio. Fresno 7J^' Quad- a particular specimen. In other cases rangle. Specimens collected from a the variation appears to be biologically 1.0 foot shale zone just above the controlled. It is doubtful that any of Lower Mercer Limestone. these specimens show true coloration, as Ga-1. The Cambridge Limestone and Shale exposed in a small abandoned quarry, present during life, but only remnants of WJ^SE^ sec. 25, approx. 1.0 mi. north- the original color as a result of preserva- east of New Concord, Adams Town- tion vagarities. Preservation may ac- ship, Guernsey County, Ohio. Bloom- field iy<i Quadrangle. Specimens col- count for the differences in cases of ap- lected from shale masses on the spoil parent reversal of dark and light bands banks. on specimens of the same species. Gwe-1. The Cambridge Limestone and Shale Better ophon (Bellerophon) graphicus exposed in the large abandoned John Moore. Three specimens were described Gress & Sons quarry, NW^NWJ^' sec. 2, north of U.S. 40 and 0.25 mi. east of by Webb (1972) from the Cambridge New Concord, Westland Township, Shale at locality Gwe-1. The pattern Guernsey County, Ohio. New Con- consists of a broad concentration of dark Ohio I. Sci. FOSSIL GASTROPOD COLOR PATTERNS gray pigment along the median portion is continuous for the population. A few of the shell which does not extend into specimens have reddish-brown bands. A the umbilical areas. Anteriorly, the pig- single specimen of this species, with a ment is interpreted by a V-shaped non- color pattern, is known from the Lower pigmented zone which is followed by a Mercer Shale at locality CS1-1 and a V-shaped pigmented zone and then, a large population, with preserved color nonpigmented zone with the V's of the patterns, has been found in the Vanport pattern open anteriorly (figs. 1 and 2). Shale at locality Jmi-2. Better ophon (Pharkidonotus) percari- Euconospira lurbiniformis (Meek & natus (Conrad). One specimen from the Worthen). Two specimens are known, Columbiana Limestone at locality Cp-3 one each from the Lower Mercer Lime- was described by Sturgeon (1964). The stone at locality LIuc-1 and the Vanport pattern consists of wide revolving dark Limestone at locality Mp-2. The former bands on each side of the shell which are was described by Lee (1971) and is a located closer to the lateral margins than poorly preserved fragment from which it to the median line. The bands on this is difficult to interpret the color pattern specimen, are 2.0 mm in width with dis- although it shows a variable transverse tinct margins and are darker in the outer zigzag pattern. The Vanport specimen portion of the band (fig. 5). Four addi- was described by Sturgeon (1964) and tional small specimens from the Cam- shows a series of transverse zigzag bands bridge Shale from localities Gwe-1 and of variable width and spacing. The Ga-1 have indications of the same general bands reach from the upper to the lower pattern but with reversed placement of sutures with the V's pointing towards light and dark bands (figs. 3 and 4). the aperture at the lower suture and Knightites (Cymatospira) sp.
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