. Bulletin of the British Museum (Natural History), Geology. SYSTEMATICS OF MELICERITITID CYCLOSTOME BRYOZOANS 35. Figs 80-83 Elea subhexagona sp. nov. 80, DM un-numbered, Voigt photocard 2060, holotype, Upper Turonian, 'Oberen Planers', Strehlen, Dresden, Germany, autozooids, mostly with opercula, and eleozooids, x 45. 81-83, ZMC Levinsen Collection M54, Turonien' [probably Cenomanian], St Calais, Sarthe, France; 81, autozooids and a primary eleozooid containing an intramural eleozooid, x 70; 82, autozooidal operculum, x 210; 83, autozooidal aperture, x 210. pseudoporous exterior wall, which
. Bulletin of the British Museum (Natural History), Geology. SYSTEMATICS OF MELICERITITID CYCLOSTOME BRYOZOANS 35. Figs 80-83 Elea subhexagona sp. nov. 80, DM un-numbered, Voigt photocard 2060, holotype, Upper Turonian, 'Oberen Planers', Strehlen, Dresden, Germany, autozooids, mostly with opercula, and eleozooids, x 45. 81-83, ZMC Levinsen Collection M54, Turonien' [probably Cenomanian], St Calais, Sarthe, France; 81, autozooids and a primary eleozooid containing an intramural eleozooid, x 70; 82, autozooidal operculum, x 210; 83, autozooidal aperture, x 210. pseudoporous exterior wall, which can be seen within the aperture of one zooid (Fig. 91), is interpreted as a bioclaus- tration ( an embedment structure formed by the bryo- zoan; cf. similar structures in Cretaceous onychocellids attributed to the presence of folliculinid protists by Ernst, 1985). Interzooidal walls with conspicuous pores. Mural spines present in great abundance in the proximal parts of zooids, long, and either simple or branched (Fig. 93). Eleozooids unknown, presumed absent. Kenozooids sometimes present. Gonozooid known from only one partly developed example (Fig. 94) showing the tubular, densely pseudoporous proximal part of the frontal wall emerging from the aperture of the maternal zooid. Measurements. autozooids (10 zooids from BMNH 60531) frontal length: mean = 0-55 mm; SD = 0-036 mm; CV = 6-6; range = 0-50-0-60 mm frontal width: • mean = 0-35 mm; SD = 0-027 mm; apertural length: apertural width: CV = 7-8; range = 0-32-0-39 mm mean = 0-29 mm; SD = 0-015 mm; CV = 5-2; range = 0-27-0-32 mm mean = 0-20 mm; SD = 0-011 mm; CV = 5-2; range = 0-20-0-23 mm Remarks. The large size and characteristically bell-shaped autozooidal apertures immediately distinguish this uncom- mon species from others in the genus. E. triangularis is the only bifoliate melicerititid described from the Lower Creta- ceous. It is also currently unique in being the only melicer- ititid known to possess mural spines (
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