118 



A.B. SMITH ETAL. 



Tholaster muiiieri (Seunes, 1889) 



PI. 6, figs 6-8; Fig. 26 



1889 Gibbaster munieri Seunes: 819, pi. 27. fig. 1. 

 1 89 1 Tholaster munieri Seunes: 23. 



Diagnosis. As for genus. Test up to 45 mm in length; slightly 

 longer than wide. Both specimens crushed and height unknown. 



Occurrence. Upper Upper Maastrichtian, Bidart, Pyrenees- 

 Atlantiques, France. The type comes from the Maastrichtian of the 

 same region (Lasseube) and it has been recorded from several other 

 localities in the Department of Landes, France. 



Material studied. BMUW 74768, 94993. 



Remarks. The long, deep frontal groove and prominent primary 

 tubercles make this a very easily recognizable species. 



Genus PSEUDOF FASTER Lambert, in Lambert & Thiery, 1924 



Diagnosis . Test ovate with anterior sulcus present only below the 

 ambitus. Ambulacra composed of tall plates with rudimentary pores. 

 Apical disc holasterid, with four gonopores. Periproct high on steep 

 posterior face. Peristome small, facing forwards and opening into 

 anterior sulcus. Marginal fasciole present. 



Pseudoffaster caucasicus (Dru, 1884) PI. 7, figs 7-10; 



Fig. 27 



1884 Ojfaster caucasicus Dru: 514, pl. 26, figs 5-10. 

 1927 Pseudoffaster caucasicus (Dru); Lambert: 42. 



Diagnosis. As for genus. Test 20.3 mm in length, ovate in outline; 

 width approximately 90% of length; widest approximately midlength. 

 Height 90% of length, with strongly convex lower surface and tallest 

 point immediately anterior of the apical disc. 



Occurrence. Maastrichtian of Sarasate, Navarra, Spain. Also 

 recorded from the Lower Maastrichtian Areny Sandstone of Tremp, 

 Catalonia, Spain, by Lambert (1927). 



Material studied. BMNH EE6234. 



Genus GALEASTER Seunes, 1889 



Diagnosis. Test ovate with shallow anterior sulcus persisting to 

 the peristome. Tall, vaulted upper surface and keeled lower surface. 

 All ambulacra with tall plates and rudimentary pores. Apical disc 

 holasterid, with four gonopores; anterior pair of genital plates gener- 

 ally fused. Periproct high on steep posterior face. Plastron 

 orthostemous. Peristome small, facing forwards and opening into 

 anterior sulcus. Subanal fasciole present. 



Galeaster bertrandi Seunes, 1 889 



PI. 4, figs 14-18; Fig. 28 



1 889 Galeaster bertrandi Seunes: 822, pl. 27, figs 2, 3. 



Diagnosis. Test length 11.1 mm, width 9.0 mm, height 9.4 mm. 

 Weakly cordiform and tapering to a point posteriorly; very tall in 

 profile with tallest point towards the posterior, sloping anteriorly and 

 with vertically truncate posterior. Lower surface strongly convex 

 with keeled posterior interambulacrum. Shallow anterior sulcus 

 from a little above the ambitus to the peristome. Apical disc plating 

 elongate, with small gonopores just apparent at this size. Ambulacral 

 plates very tall with pore-pairs centrally placed; pores double through- 

 out. 



Fig. 27 Camera lucida drawings of plating in Pseudoffaster caucasicus 

 (Dru, 1884) from the Maastrichtian of Sarasate (Navarra); BMNH 

 EE6234. a, apical surface; b. oral surface; c, lateral profile; d, posterior 

 profile. Interambulacra shaded. Scale bar = 5 mm. 



Occurrence. Maastrichtian, horizon 2, Santander. The type of 

 this species was reported from the 'Garumnian" (?Maastrichtian) of 

 the Pyrenees-Atlantiques, France. 



Material STUDIED. BMNHEE6188. 



Remarks. Unfortunately, we have only a single specimen of this 

 interesting species. The very anterior mouth, opening into the frontal 

 groove immediately distinguishes this species from Offaster. whose 

 mouth is downward-facing and not opening into an anterior sulcus. 

 Amongst holasteroids only Galeaster possesses a subanal fasciole, 

 orthostemous plating and a distinct frontal sulcus. However, the apical 

 disc has the two anterior genital plates fused in Galeaster, according to 

 Poslavskaya & Moskvin (1960), whereas our specimen undoubtedly 

 has a suture separating genital plates two and three. We do not know 

 what the apical disc plating in Seunes' type material is like. 



Order SPATANGOIDA Claus, 1876 



Diagnosis. Ovate to heart-shaped with compact apical disc with 

 four genital plates. Posterior interambulacral plates differentiated to 

 form a plastron adorally. Aboral ambulacra typically with pore-pairs 

 enlarged and forming petals; often depressed. 



Family MICRASTERIDAE Lambert 1920 



Diagnosis. Apical system ethmophract; plastron mesamphi- 

 stemous. Aboral tuberculation consisting of larger primary tubercles 

 dispersed amongst a dense groundmass of fine granules. 



