Allometric shell growth in infaunal burrowing bivalves: examples of the archiheterodonts Claibornicardia paleopatagonica (Ihering, 1903) and Crassatella kokeni Ihering, 1899
- Published
- Accepted
- Subject Areas
- Evolutionary Studies, Marine Biology, Paleontology, Zoology
- Keywords
- Geometric Morphometrics, Ontogeny, Crassatella, Claibornicardia, Allometric growth, Paleoecology, Archiheterodonta, Elliptic Fourier Analysis
- Copyright
- © 2018 Perez et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- 2018. Allometric shell growth in infaunal burrowing bivalves: examples of the archiheterodonts Claibornicardia paleopatagonica (Ihering, 1903) and Crassatella kokeni Ihering, 1899. PeerJ Preprints 6:e26892v1 https://doi.org/10.7287/peerj.preprints.26892v1
Abstract
We present two cases of study of ontogenetic allometry in outlines of bivalves using longitudinal data, a rarity among fossils, based on the preserved post-larval record of shells. The examples are two infaunal burrowing bivalves of the southern South America, Claibornicardia paleopatagonica (Archiheterodonta: Carditidae) (early Paleocene) and Crassatella kokeni (Archiheterodonta: Crassatellidae) (late Oligocene–late Miocene). Outline analyses were conducted using a geometric morphometric approach (Elliptic Fourier Analysis), obtaining successive outlines from shells’ growth lines, which were used to reconstruct ontogenetic trajectories. In both taxa, ontogenetic changes are characterized by the presence of positive allometry in the extension of posterior end, resulting in elongated adult shells. This particular allometric growth is known in others infaunal burrowing bivalves (Claibornicardia alticostata and some Spissatella species) and the resulting adult morphology is present in representatives of several groups (e.g. Carditidae, Crassatellidae, Veneridae, Trigoniidae). Taxonomic, ecological and evolutionary implications of this allometric growth pattern are discussed.
Author Comment
This is a submission to PeerJ for review.
Supplemental Information
Data S1. Sample details
Data from material used in this study, including both species, Claibornicardia paleopatagonica (Ihering, 1903) and Crassatella kokeni Ihering, 1899). Collection abbreviations mentioned in the main manuscript.
Data S2. Fourier coefficientes for outlines of Claibornicardia paleopatagonica
Includes Area (in mm2), growth categories, identifier and Fourier coefficients.
Data S3. Fourier coefficientes for outlines of Crassatella kokeni
Includes Area (in mm2), growth categories, identifier and Fourier coefficients.
Data S4. Results from Analyses of Claibornicardia paleopatagonica
Includes results of PCA and MRA analyses.
Data S5. Results from Analyses of Crassatella kokeni
Includes results of PCA and MRA analyses.