THE DEMOSPONGE GENUS LEPTOMITUS and A NEW SPECIES FROM THE MIDDLE CAMBRIAN OF SPAIN

Forty-five specimens of Leptomitus conicus sp. nov. have been collected from the base of the Murero Formation (Caesaraugustan, Middle Cambrian) in the Murero area of Zaragoza, north-east Spain. The new species is a small obconical sponge, which has coarse oxeas forming parallel rods that run the whole length of the specimens in the man- ner typical of the genus. The biostratigraphy and facies of the levels with Leptomitus conicus have been analysed. Palaeoeco- logical information derived from associated trilobites, brachio- pods and ichnofossils shows that L. conicus lived in a soft substrate of a sublittoral environment of low to low ⁄ moderate energy. According to established Cambrian pal…