Project 5186: A. B. Smith. 2001. Probing the cassiduloid origins of clypeasteroid echinoids using stratigraphically restricted parsimony analysis. Paleobiology. 27 (2):392-404.
Abstract
Clypeasteroid echinoids are a familiar and easily defined clade with a cryptic origin. They first appear in the late Paleocene and are believed to have arisen from cassiduloid ancestry, but identifying sister-group relationships more precisely has proved difficult. Two factors are responsible for this problem, the extreme morphological conservatism of cassiduloids, which has given rise to high levels of character exhaustion, and the origin of crown-group clypeasteroids through paedomorphosis. Previous analyses, based on extant representatives alone or including all Mesozoic to Recent genera, have proved unsatisfactory. Here a parsimony analysis is undertaken using a restricted set of all stem-group clypeasteroids and cassiduloid taxa that existed immediately prior to the appearance of crown-group clypeasteroids. Inclusion of Togocyamus , the fossil taxon lying closest to the origin of crown-group clypeasteroids, is phylogenetically uninformative because that taxon is highly paedomorphic and has only generalized juvenile characteristics. However, earlier stem-group plesions provide critical data that identify Apatopygidae as extant sister group to the Clypeasteroida. Stratigraphically restricted analyses cannot eradicate the problems that arise from character exhaustion, but can minimize these with respect to specific phylogenetic questions.Read the article »
Article DOI: 10.1666/0094-8373(2001)027<0392:PTCOOC>2.0.CO;2
Project DOI: 10.7934/P5186, http://dx.doi.org/10.7934/P5186
This project contains | Matrices |
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Download Project SDD File | Total scored cells: 1747 Total media associated with cells: 0 Total labels associated with cell media: 0 |
Characters | |
Total characters: 41 Total characters with associated media: 0 Total characters with media with labels: 0 Total character states: 112 Total character states with associated media: 0 Total character states with media with labels:0 Total unordered/ordered characters:41/0 |
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MorphoBank Project 5186
MorphoBank Project 5186
- Creation Date:
31 March 2024 - Publication Date:
01 April 2024 - Project views: 939
Authors' Institutions
- Natural History Museum, London
Members
member name | taxa | specimens | media | chars | character
| cell scorings (scored, NPA, "-") | cell
| rules | ||||||
Shreya Jariwala Project Administrator | 43 | 5 | 5 | 41 | 0 | 0 | 1747 (1747, 0, 0) | 0 | 0 | 0 |
Taxonomic Overview for Matrix 'M29778' (43 Taxa)
taxon | unscored cells |
scored cells |
no cell support |
NPA cells |
"-" cells | cell images | labels on cell images |
member access |
[1] † Nucleopygus Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[2] † Pygopistes Last Modified in 03/31/24 | 2 | 39 | 39 | 0 | 0 | 0 | 0 | 1 |
[3] † Plagiochasma Last Modified in 03/31/24 | 2 | 39 | 39 | 0 | 0 | 0 | 0 | 1 |
[4] † Amblypygus Last Modified in 03/31/24 | 2 | 39 | 39 | 0 | 0 | 0 | 0 | 1 |
[5] † Catopygus Last Modified in 03/31/24 | 2 | 39 | 39 | 0 | 0 | 0 | 0 | 1 |
[6] † Parapygus Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[7] † Zuffardia Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[8] † Faujasia Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[9] † Domechinus Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[10] † Oolopygus Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[11] † Studeria Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[12] † Pisolampas Last Modified in 03/31/24 | 2 | 39 | 39 | 0 | 0 | 0 | 0 | 1 |
[13] † Petalobrissus (petalobrissus) Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[14] † Petalobrissus (paralampas) Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[15] † Harduinia mortonis Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[16] † Harduinia kellumi Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[17] † Gongrochanus Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[18] † Platypygus Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[19] † Stigmatopygus Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[20] † Rhynchopygus Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[21] † Procassidulus Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[22] † Rhyncholampas Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[23] † Eurhodia Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[24] † Cassidulus Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[25] † Pygurostoma Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[26] † Clypeolampas Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[27] † Vologesia Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[28] † Gitolampas abiadensis Last Modified in 03/31/24 | 1 | 40 | 40 | 0 | 0 | 0 | 0 | 1 |
[29] † Gitolampas tunetanus Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[30] † Neocatopygus Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[31] † Arnaudaster Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[32] † Echinolampas alta Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[33] † Echinolampas leymeriei Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[34] † Plesiolampas Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[35] † Apatopygus Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[36] † Oriolampas Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[37] † Termieria Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[38] † Pseudopygaulus Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[39] † Conoclypeus Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[40] † Oligopygus Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[41] † Haimea Last Modified in 03/31/24 | 0 | 41 | 41 | 0 | 0 | 0 | 0 | 1 |
[42] † Togocyamus Last Modified in 03/31/24 | 3 | 38 | 38 | 0 | 0 | 0 | 0 | 1 |
[43] † Nucleolites Last Modified in 03/31/24 | 2 | 39 | 39 | 0 | 0 | 0 | 0 | 1 |
Project views
type | number of views | Individual items viewed (where applicable) |
Total project views | 939 | |
Project overview | 56 | |
Bibliography | 26 | |
Documents list | 38 | |
Views for media list | 43 | |
Matrix views | 56 | Matrix landing page (46 views); Smith 2001 (10 views); |
Specimen list | 170 | |
Media views | 256 | Media search (135 views); M902843 (25 views); M902842 (24 views); M902841 (26 views); M902840 (23 views); M902839 (23 views); |
Taxon list | 294 |