The Echinoid Directory

Characters and data matrix for cladogram

This cladogram is a semistrict consensus of 1601 equally parsimonious trees found from the following data matrix (see Smith, A. B. 2004. Phylogeny and Systematics of holasteroid echinoids and their migration into the deep-sea. Palaeontology 47, 1-28).
Character descriptions:
1. Frontal groove aboral to ambitus: absent (0); shallow indentation at ambitus, weakly defined aborally (1); deep groove on aboral surface, with lateral carina (2).
2. Frontal groove on oral surface: absent (0); present as shallow, poorly-defined depression (1); distinct channel leading to the peristome (2).
3. Posterior ocular plates: disjunct from remainder of apical disc (0); only one of the posterior ocular plates in contact with the posterior genital plates (1); both posterior ocular plates in firm contact with the posterior genital plates (2).
4. Anterior genital plates: separate (0); reduced to a single plate by loss or fusion (1)
5. Hydropore openings: confined to genital plate 2 (0); scattered over all anterior ocular and genital plates (1).
6. Number of gonopores (genital plates only): 4, one to each genital plate (0); 3 (no gonopore in genital plate 2) (1); 2 (no gonopores in posterior genital plates) (2).
7. Gonopores in ocular plates II and IV: no (0); yes, single (1); yes, multiple (2).
8. Position of apical disc: subcentral (0); closer than 20% test length to anterior (1).
9. Labral plate followed by a single plate posteriorly; no (0); yes (1).
10. First sternal plate largest (plastron meridosternous); no (0); yes (1).
11. Sternal plates 5.a.2, 5.b.3 uniserial (plastron metasterrnous); no (0); yes (1).
12. Sternal plates 5.a.2 to 5.a.3 forming a straight line and effectively symmetric; no (0); yes (1).
13. Episternals (5.a.2, 5.b.3) effectively paired and opposite, with suture to rear almost straight (less than 10% offset relative to plate height) (plastron orthosternous): no (0); yes (1).
14. Plates forming rear of plastron: biserial - 4a/5b or greater (0); paired post-episternals (1) paired episternals (2).
15. Rostral plate: absent (0); present (1).
16. Plastron disjunct: no (0); yes (1).
17. Anterior interambulacral plating: amphiplacous (0); meridoplacous (1).
18. Lateral interambulacral plating: amphiplacous (0); meridoplacous (1).
19. Lateral interambulacra disjunct adorally; no (0); yes (1).
20. Plate (numbered from the peristome) that lies adjacent to rear of labral plate in ambulacrum I: 1 (1); 2 (2); 3 (3).
21. Plate (numbered from the peristome) at rear suture of plastron plate 5.b.3 (left episternal in oral view) in ambulacrum I: 6 or 7 (0); 5(2); 4 (3).
22. Aboral ambulacral plates: narrow and crowded (0); large and hexagonal - approximately the same height as interambulacral plates (1).
23. Aboral ambulacral pores: single and rudimentary (0); double, with the two columns equal (1); double with a strong inequality in the size of pore-pairs in the anterior and posterior columns (2).
24. Aboral pores in frontal ambulacrum well developed and identical to those in paired ambulacra: no (0); yes (1).
25. Posterior ambulacra strongly flexed on aboral surface: no (0); yes (1).
26. Labral plate curves out to form a prominent lip: no (0); yes (1).
27. Peristome orientation: approximately horizontal or gently inclined to lower surface (0); steeply inclined or vertical (1).
28. Periproct opening framed on oral side by interambulacral plates 5.a.4/5.b.5 (0); 5.a.5/5.b.6 (1); 5.a.6/5.b.7 or above (2).
29. Periproct in adult: supramarginal, with distinct subanal shelf (0); marginal, on vertically truncate face (1); inframarginal (2); on oral surface (3).
30. Subanal fasciole: absent (0); present, crossing plates 5.a.2/5.b.3 on its adoral side (1); present crossing plates 5.b.4/5 and 5.a.4 on its adoral side (2).
31. Subanal fasciole on periproctal side passes over: plates 5.a.5/5.b.6 (1); plates 5.a.4/5.b.5 (2).
32. Marginal fasciole: absent (0); present around posterior only (1) present around entire test margin (2).
33. Beneath the periproct the marginal fasciole passes over: plates 5.a.5/5.b.6 (1); 5.a.4/5.b.5 (2).
34. Tuberculation style: no primary tubercles (0); primary tubercles present along anterior groove and adapical zone only (1); primary tubercles scattered over aboral interambulacral plates (2); primary tubercles confined to supra-ambital band (3).


Eoholaster .................00100 00000 00000 00003 10100 00210 0000
Pseudholaster ..........21200 00000 00000 00003 10100 00210 0000
Giraliaster ..................21200 00000 00000 00002 10100 00212 1000
Protocardiaster.......... 21200 00000 00000 01102 10100 00210 0100
Cardiaster...................21200 00010 10000 01102 10100 00210 0101
Sternotaxis.................11200 00010 11000 01102 10100 00210 0100
Infulaster.....................22210 00110 11000 0?1?2 20100 01210 0101
Hagenowia.................22010 00110 11000 1???2 20000 01210 0101
Hemipneustes............21201 00000 00000 00002 10201 10220 0000
Toxopatagus..............2120? 000?? 00??? 0???? ?0201 10?20 0000
Echinocorys...............00200 00011 00000 00003 00110 00220 0000
Pseudananchys........00201 00011 00000 00003 00110 00220 0000
Holaster......................11200 00011 00000 01103 00100 00210 0002
Jeronia........................00200 10011 00000 01102 21100 00030 0003
Cibaster......................11200 00011 00000 01102 20100 00210 0200
Offaster.......................01200 00011 00000 01102 21100 00210 0200
Galeola.......................01200 00011 00000 01102 21100 00220 0000
Crassiholaster...........11200 00011 00000 00002 20100 01210 0000
Lampadocorys..........02200 00011 00000 00?02 20100 00220 0??0
Pseudoffaster...........11200 00011 00110 00112 31100 01210 0210
Calymne....................01100 20011 00110 00102 31000 00210 0210
Sanchezaster...........02200 00011 00110 10?12 31000 01?10 0210
Sternopneustes........02200 00011 00110 1???2 ?1000 01120 0210
Chelonechinus.........00200 00011 00110 10?12 31000 0012? ???0
'Stegaster'.................22200 00011 00000 10112 211?0 00200 0?00
Rispolia....................22200 00011 00000 0???2 20100 00200 0?00
Entomaster...............22200 00011 00110 0???? ?0100 01200 0202
Guettaria...................22200 01011 00110 00112 20100 01200 0203
Seunaster.................22200 00011 00110 ??112 20100 01200 0?03
Tholaster..................22200 00011 00000 0?1?? ?0100 0?200 0?02
Garrumnaster..........00200 10011 00120 01102 20100 00?0? 0000
Huttonechinus.........01200 00011 00121 00002 20100 00221 2000
Corystus...................00200 00011 00121 00002 20100 00201 2000
Cardabia..................00200 10011 00121 00002 20100 00211 2000
Antrechinus.............00200 00011 00100 01102 21000 00111 2000
Cystechinus............00210 00011 00100 01103 21000 0012? ?000
Urechinus...............00200 10011 00100 01102 31000 00121 2000
Plex-cinctus............00010 20011 00120 11102 31000 00201 1000
Plex-spect ..............00210 00011 00120 11102 31000 00201 1000
Plex-sulcatus..........12010 20011 00120 1?102 31000 00211 10?0
Galeaster................22010 02011 00120 00112 21100 01211 10?0
Pourtalesia.............12010 02111 00120 11112 31000 01201 20?0
Basseaster..............02000 00011 00120 01102 31100 00?1? ?0?0