124 



A.B. SMITH ETAL. 



Occurrence. Danian of Erice, Navarra Province, Spain; Lower 

 Maastrichtian of Tercis, Landes, France. 



MATERIAL STUDIED. BMNH EE6206-07, MGB 37305-06, 373 1 9- 

 21. BMUW 95007, 95008, 95009, 96010, 9501 1, 95019, 95016. 



Remarks. Differs from the rather similar-shaped Cyclasterheberti 

 (Nickles), from the Maastrichtian of Santander, in having much 

 more widely divergent anterior petals and a less parallel-sided 

 outline. Differs from the contemporary C. aturicus in being much 

 less cordiform in outline. 



Cyclaster aturicus (Seunes, 1888) 



PI. 9, figs 15-17; Figs 31c, 32 



Isopneustes aturicus Seunes: 797, pi. 28, fig. 3. 



Diagnosis. Test up to 35 mm in length; cordiform in outline with 

 the widest point just behind the anterior petals; tapering posteriorly 

 to a truncated point; rounded anteriorly with a distinct anterior 

 sulcus. Width 85-90% of length. Posterior interambulacrum devel- 

 oped as a keel aborally. Anterior and posterior petals similar in 

 length; anterior pair diverging at about 130°, posterior at about 50°; 

 18 pore-pairs in petals 6.5 mm in length. Patches of dense granula- 

 tion at the ends of petals and in the posterior interambulacrum, but no 

 continuous fasciole developed. 



Occurrence. Danian, Erice and Astieso, Navarra Province, Spain. 



Material studied. BMNH EE6068, EE6208-6209. 



Remarks. This species has the same petal form as C. gindrei, with 

 which it co-occurs, but differs from that species in having a wider, 

 more cordiform test. 



Cyclaster heberti (Nickles, 1892) PI. 8, figs 6, 7; Fig. 31a 



1892 Isopneustes Heberti Nickles: 1 1 1, pi. 9, figs 12, 13. 



1973 Isopneustes heberti'H'\cV\h?,\Radig. 62,^1. 10, fig. 8, pi. II, 



figs 1,2. 

 1995 Isopneustes Iteberti Nickles; Gallemi et al.: 269, table I . 



Diagnosis. Test up to 25 mm in length (known to reach up to 45 

 mm elsewhere). Elongate and subquadrate in outline and with very 

 flattened profile: no posterior keel. Test widest at a point immedi- 

 ately behind where the anterior ambulacra reach the ambitus in plan 

 view; rounded in front without any anteal sulcus. Test tapering 

 slightly to posterior truncation. Anterior petals 30^0% longer than 

 posterior petals; diverging at 90° or slightly less. Posterior petals 

 diverging at 45-50°. No peripetalous fasciole developed, even 

 posteriorly, although traces of granulation may be present around the 

 posterior. 



Occurrence. Maastrichfian, horizon 6, of Santander, Cantabria, 

 Spain. 



Material studied. MGB37550-5 1 . 



Remarks. Distinguished from the rather similar-shaped C. gindrei 

 by the angle of divergence of its anterior petals, and by its lacking a 

 posterior keel. C. heberti was first described from El Matet, Alicante 

 Province, Spain. Topotype material from here reaches 45 mm in 

 length and show variable development of the peripetalous fasciole. 

 Most specimens show traces of the fasciole at the base of the 

 posterior petals while some have more continuous fascioles. A few 

 appear to lack any trace of a peripetalous fasciole whatsoever. Our 

 specimens from Santander show no trace of a peripetalous fasciole. 



ICyclaster sp. 



Occurrence. Maastrichtian, horizon 4, Olazagutia Pass, and 

 Maastrichtian, black shale facies, Sarasate, Navarra Province, Spain. 



Material studied. BMNH EE62 1 0, EE62 1 1 . 



Remarks. The specimen from Olazagutia Pass is a large crushed 

 individual, esfimated at 35 mm in length and about 30 mm in width. 

 The apical disc is unfortunately lacking, but the test is cordiform 

 with distinct frontal sulcus and short, well-formed, sunken petals. 

 There is a strong subanal fasciole, but no trace of a peripetalous 

 fasciole. The peristome is non-labiate. The style of aboral 

 tuberculation shows this to be a micrasterid, while the lack of a 

 peripetalous fasciole, relatively short petals and non-labiate peristome 

 suggests Cyclaster. However, without better material we cannot be 

 sure about its taxonomic placement. It most closely resembles C. 

 aturicus (Seunes) in shape. 



The specimen from Irurtzun is badly weathered aborally, but is 

 also rather broad and weakly cordate and is similarly only tentatively 

 assigned to Cyclaster. 



Genus ISASTER Desor, 1858 



Diagnosis. Ovate micrasterids with weakly conical profile and no 

 frontal sulcus. Apical disc with three gonopores, genital plate 2 

 lacking a pore. Petals weakly depressed adapically; pore-pairs in all 

 five ambulacra similar. Periproct inframarginal, on inward sloping 

 posterior face. No fascioles. 



Isaster aquitanicus (de Grateloup, 1836) 



PI. 9, figs 18-21; Figs 33, 34 



1836 Spatangus aquitanicus de Grateloup: 176, pi. 2, fig. 17. 



Diagnosis. Large tests, up to 65 mm in length, oval in outline and 

 tapering to the posterior. Width 85-95% of length, height 60-70% of 

 length. In profile low domal to subconical with the tallest point 

 coincidental with the apical disc. Apical disc AO—M% test length 

 from anterior; ethmophract. Petals rather short and a little depressed; 

 the two columns being only weakly convergent distally. Anterior 

 paired petals extending only about half the radial distance to the 

 margin, slightly bowed and widely divergent. Posterior petals simi- 

 lar in length to anterior paired petals, but much less divergent. 

 Anterior ambulacrum with enlarged pores in adapical part, which is 

 slightly depressed. This frontal groove is lost towards the ambitus. 

 Peristome kidney-shaped in outline; 20-25% test length from the 

 anterior; downwards facing. Labral plate long and narrow; not 

 projecting over the peristome; sternal plates subequal. Oral surface 

 slightly convex with median part of ridge forming a weak ridge. 



Occurrence. Upper Thanetian, P. pseudomenardii Zone, Casas 

 de Oraien, Navarra province. Spain. 



Material studied. 71 specimens, including BMNH EE4522- 

 29, EE6069, EE6202-05, MGB 37406-16, 37433-35. 



Remarks. This is the most common species from Casas de Oraien. 

 One-quarter of our specimens have been bored by predatory gastro- 

 pods. 



Family HEMIASTERIDAE Clark, 1917 



Diagnosis. Spatangoids with peripetalous fasciole, but no subanal 

 fasciole. Dense uniform aboral tuberculation with few intervening 

 granules. 



