DOI: 10.5061/dryad.q64g3
title: Data from: Unraveling species concepts for the Helicoprion tooth whorl

description: The genus Helicoprion (Chondricthyes: Euchondrocephali) is preserved
 primarily by a continuous spiral root that forms the base for more than
 130 teeth. Helicoprion is found globally in Lower Permian marine rocks and
 at least 100 specimens exist in public collections worldwide. Ten species
 of the genus are reviewed in the context of new morphometric analyses
 conducted on dozens of specimens. Helicoprion whorls share a common inner
 spiral geometry that results in exponential growth of tooth and root
 dimensions. Novel growth equations permit calculation of whorl diameter,
 volution number and tooth count from incomplete specimens. The results of
 meristic and geometric analyses identify taxobases that distinguish three
 emended species concepts. Differentiation of form is evident among
 specimens only after the second volution or roughly the 85th tooth.
 Helicoprion davisii has widely-spaced, stout teeth with tall cutting
 surfaces and is distinguished from H. bessonowi, whi ch has narrow,
 closely-spaced teeth with short cutting surfaces. H. ergassaminon is an
 intermediate form, having narrow, closely-spaced teeth with tall cutting
 surfaces. Several large specimens in the study are too dissimilar to place
 in the new emended species concepts.
description: Supplemental Table
 1Database of figured and
 reposited Helicoprion specimens. Column abbreviation and notes: #,
 database index number; Inst Acro, Institutional acronym for specimen;
 Spec., Specimen number; Notes & Alt name, notation on synonymous
 specimen numbers and counterparts (cp); Locality#, registered locality
 number; Lat, latitude in decimal degrees; Long, longitude in decimal
 degrees; Place, town or region; Country, country; Museum, institutional
 abbreviations listed below; Stratigraphy, formation and member; Stage,
 based on current stratigraphy, Art=Artinskian, Kung=Kungurian, Leon=
 Leonardian, Olen=Olenekian, Road=Roadian, Wolf=Wolfcampanian; Original ID,
 specimen diagnosis according to reference or repository, [H]=holotype,
 [L]=lectotype; Whorls, specimen quality including number of volutions (w),
 or number of teeth (t), whether partial (p) or a complete whorl (c),
 frags=fragments; Diagnosis, our assessment according to the emended
 diagnoses presented in this paper. Institutional Abbreviations.—AMNH,
 American Museum of Natural History, New York, USA; BANFF, Banff Park,
 Alberta, Canada; ER, Ekaterinburg Regional Natural History Museum, Russia;
 FCMP, Museo de Paleontologia de la Facultad de Ciencias, Universidad
 Nacional Autonoma de Mexico; FH, Fort Hall Reservation, Shoshone Bannock
 Tribal Museum, Idaho, USA; FIELD, Field Museum, Chicago, USA; GSA,
 Geological Society of America Office, Denver, USA; IMNH, Idaho Museum of
 Natural History, Pocatello, USA; KCL, Kesen-numa City Library, Japan; KSU,
 Geological Museum of Kazan State University, Russia ; LACM , Los Angeles
 County Museum, USA; MNH, Museum of Natural History, University of Kansas,
 Lawrence, USA; NHMU, Natural History Museum of Utah, Salt Lake City, USA;
 NMC, Canadian Museum of Nature, Ottawa, Canada; PIN, Palaeontological
 Institute of the Russian Academy of Sciences, Moscow, Russia; PERM, Perm
 Regional Natural History Museum, Russia; PMO, Paleontologisk Museum, Oslo,
 Norway; PRIV, Private Collection; TsNIGR, Central Research Geological
 Museum, St.-Petersburg, Russia; UCMP, University of California Museum of
 Paleontology, Berkeley, USA; UFH, Utah Field House of Natural History
 State Park Museum, Vernal, USA; UMUT, University Museum, University of
 Tokyo, Japan; UNR, W.M. Keck Earth Science and Mineral Engineering Museum,
 University of Nevada, Reno, USA; USNM, National Museum of Natural History,
 Washington DC, USA; YIGM, Yichang Institute of Geology and Mineral
 Resources, China; WAMAG, Western Australian Museum, Perth,
 Australia.SupplentalTable1.xlsxSupplemental table 2First two principal components for PC analyses in Figures 9 and 10. Current and previous species diagnosis reported where appropriate. *Abbrev: (H) holotype, (L) lectotype, (T) type; **ital.=estimated tooth number from Table 7.