thiolliericrinid crinoids from the lower cretaceous of crimea

— 639 —Thiolliericrinus t orosus nov. sp.D e r iv a t io n o m i n i s :figs. 4 D ; 6 B-EThe name of the species comes from « torosus »(pustulous in Latin).H o l o t y p e :CK-86-1 (fig. 6 B) ; Leningrad Mining Institute.Ty p e l o c a l it y :Kuibyshevo, Belbek Valley, Crimea.Ty p e l e v e l :Upper Berriasian.T y p e l e v e l :Upper Berriasian.D e s c r i p t i o n :The calyx is low, conical, abruptly narrowed downwardswith the rounded-pentangular outline. Thebasais are visible on the calyx surface as small convextriangular plates. The external radial surface is verylow, overlapping the centrodorsal, and covered withbig irregular knobs. The calyx cavity is broad andshallow. 10 furrows go between the radiais and arefully pronounced on their middle part. The innerradial surface is slightly striated. The basais are notvisible on the bottom of the calyx cavity. The primaxillaryhas a muscular lower surface. Its externalsurface is tumid, cone-likely and covered with bigknobs. The height of the centrodorsal is about equalto the radial height, but the diameter of the centrodorsalis notably smaller than that of the radial ring.Three cirrus sockets are placed close to each otherunder each radial. Two large sockets are situated nearerto the radial and a small one is placed below, betweenthe large ones. 15 sockets in all. The lower centrodorsalface is convex, ovate = oblong and has afulcral ridge with two narrow interrupted depressionson both sides, surrounded by a weak marginal ridge.D im e n s io n s :Ht = 7.2 mm ; Dt = 10.8 mm ; Dc = 6.0 mm ; A f= 57° ; Hr : H t = 0.07 - 0.11 ; Bf : Lf = 0.44 - 0.55.Co m p a r is o n :The centrodorsal of T. torosus is similar to that ofT. arzierensis but has a considerably greater numberof the cirrus sockets (15 againts 6-8) being placedregularly.M a t e r i a l s :2 calyxes, 1 centrodorsal, 2 radiais, 5 brachials, 4 cirrals(see table 1).D i s t r i b u t i o n :Berriasian ; Crimea.Genus Burdigalocrinus Ja e k e l , 19181918 — Burdigalocrinus : Ja e k e l , p.71.1924 — Burdigalocrinus Ja e k e l : Gislén, p. 188.1933 — Burdigalocrinus Ja e k e l : Dacqué, p. 103.1953 — Burdigalocrinus Ja e k e l : Sieverts-Doreck(in Ubaghs), p. 758.1961 — Burdigalocrinus Ja e k e l : Rasmussen, p.213.1978a —Burdigalocrinus Ja e k e l : Roux, p. 234.1978b —Burdigalocrinus Ja e k e l : Roux, p. A 20.1978c —Burdigalocrinus Ja e k e l : Rasmussen, p.880.T y p e s p e c ie s :Burdigalocrinus lorioli Ja e k e l , 1918.D i a g n o s i s :The radiais have high free external surface. Thebasais are visible on the calyx surface. Cirrus socketsare absent but there are structureless fossae placed, asa rule, regularly. The centrodorsal is high and conical.The stem facet is wide, elliptical and flat.Two species : B. lorioli Ja e k e l , B. maximus nov.sp.Upper Jurassic (Oxfordian) - Lower Cretaceous(Berriasian) ; Portugal, Crimea.Burdigalocrinus lorioli Ja e k e l , 1918 (p. 72, fig. 64D,E) (= Thiolliericrinus ribeiroi D e L o r i o l , 1891, p.165 ex parte, pi. 29, fig. 17, non fig. 16, 18-22 =Thiolliericrinus ribeiroi) (Burdigalocrinus lorioli :Gislén 1924, p. 190 ; Rasmussen 1961, p. 213 ; 1978c,p. 881, fig. 588-4 ; Roux 1978b, p. A 20). Lusitanian ;Engenheiro (Ribatejo), Portugal (fig. 7 A).Burdigalocrinus maximus nov. sp.fig. 7 B,C ; pl. 1, fig. 1-3D e r iv a t io n o m i n i s :The name of the species comes from « maximus »(large in Latin).H o l o t y p e :CK-78-1 (fig. 7 B) ; Leningrad Mining Institute.