Sedilichnus, Oichnus, Fossichnus, and Tremichnus: ‘Small Round Holes in Shells’ Revisited

Author:

Zonneveld John-Paul,Gingras Murray K.

Abstract

Small round pits and holes in fossil skeletal material are found in a wide variety of invertebrate substrates from diverse environmental settings. They are associated with parasitism, predation and commensal attachment. Four ichnogenera have been proposed for these trace fossils: Sedilichnus Müller, Oichnus Bromley, Tremichnus Brett and Fossichnus Nielsen, Nielsen and Bromley. Previous authors have established that Tremichnus is a junior synonym of Oichnus. Herein we show that Oichnus and Fossichnus are junior synonyms of Sedilichnus.Sedilichnus, as defined herein, includes 10 ichnospecies. Sedilichnus spongiophilus, S. simplex, S. paraboloides, S. ovalis, S. coronatus, S. gradatus, S. halo, S. asperus, S. excavatus and S. solus. Consistent with previous work Sedilichnus ichnospecies are defined solely by morphological criteria and not by a priori assumptions regarding depositional environment or tracemaker. Thus, this ichnotaxon is recognized in both marine and continental settings on a wide variety of invertebrate skeletal tests. As is true with many ichnotaxa, Sedilichnus ichnospecies represent end-members in morphological spectra, however each ichnospecies is clearly differentiable from the others.Sedilichnus spongiophilus are circular, non-penetrative pits in shells. Sedilichnus paraboloides are penetrative holes with spherical paraboloid forms and typically have larger external openings and smaller internal openings. Sedilichnus simplex are simple cylindrical borings that have both penetrative and non-penetrative forms. Sedilichnus coronatus differ from other forms by the presence of an etched or granular halo surrounding the boring. Sedilichnus gradatus have two concentric parts, an outer boring and an inner shelf of smaller diameter. Sedilichnus ovalis and S. asperus are both oval in outline differing in the presence of tapering paraboloid margins in S. ovalis and margins perpendicular to the substrate in S. asperus. Sedilichnus excavatus and S. solus are primarily non-penetrative and differ from other Sedilichnus by the presence of central, raised bosses or platforms. These two ichnospecies differ in the shapes of their external walls and the proportional thickness of the bounding groove.

Publisher

Cambridge University Press (CUP)

Subject

Paleontology

Reference96 articles.

1. Ichnology of the Pliocene Bowden Shell Bed, southeast Jamaica;Pickerill;Contributions to Tertiary and Quaternary Geology,1998

2. Biotic interactions revealed by macroborings in arctic bivalve molluscs

3. Predatory gastropods and their activities in the Blackdown Greensand (Albian) of England;Taylor;Palaeontology,1983

4. Tafonomia de formaníferos Bentônicos em sedimentos siliciclásticos e Carbonáticos;Cardosa;Anuario do Instituto de Geociências,2007

5. Gastropod predation on sympatric Neogene species of Glycymeris (Bivalvia) from the Eastern United States;Thomas;Journal of Paleontology,1976

Cited by 2 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3